,worlds ,within ,worlds3 ,the ,story of ,nuclear ,energy ,volume #c ,nuclear ,fission ,nuclear ,fusion ,beyond ,fusion by ,isaac ,asimov ,united ,states ,atomic ,energy ,commission ,office of ,information ,services ,library of ,congress ,catalog ,card ,number #ge-ahidgg #aigb ,nothing in the history of mankind has opened our eyes to the possibilities of science as has the development of atomic power4 ,in the last #bjj years1 people have seen the coming of the steam engine1 the steamboat1 the railroad locomotive1 the automobile1 the airplane1 radio1 motion pictures1 television1 the machine age in general4 ,yet none of it seemed quite so fantastic1 quite so unbelievable1 as what man has done since #aici with the atom 444 there seem to be almost no limits to what may lie ahead3 inexhaustible energy1 new worlds1 ever-widening knowledge of the physical universe4 ,isaac ,asimov ,illustration3 ,photograph of night sky ,nuclear energy is playing a vital role in the life of every man1 woman1 and child in the ,united ,states today4 ,in the years ahead it will affect increasingly all the peoples of the earth4 ,it is essential that all ,americans gain an understanding of this vital force if they are to discharge thoughtfully their responsibilities as citizens and if they are to realize fully the myriad benefits that nuclear energy offers them4 ,the ,united ,states ,atomic ,energy ,commission provides this booklet to help you achieve such understanding4 ,,united ,,states ,,atomic ,,energy ,,commission ,dr4 ,james ,r4 ,schlesinger1 ,chairman ,james ,t4 ,ramey ,dr4 ,clarence ,e4 ,larson ,william ,o4 ,doub ,dr4 ,dixy ,lee ,ray ,illustration3 ,isaac ,asimov ,,isaac ,,asimov received his academic degrees from ,columbia ,university and is ,associate ,professor of ,biochemistry at the ,boston ,university ,school of ,medicine4 ,he is a prolific author who has written over #ajj books in the past #ah years1 including about #bj science fiction works1 and books for children4 ,his many excellent science books for the public cover subjects in mathematics1 physics1 astronomy1 chemistry1 and biology1 such as ,the ,genetic ,code1 ,inside the ,atom1 ,building ,blocks of the ,universe1 ,understanding ,physics1 ,the ,new ,intelligent ,man's ,guide to ,science1 and ,asimov's ,biographical ,encyclopedia of ,science and ,technology4 ,in #aife ,dr4 ,asimov received the ,james ,t4 ,grady ,award of the ,american ,chemical ,society for his major contribution in reporting science progress to the public4 ,illustration3 ,photograph of night sky ,,contents ,,volume #a ,introduction #e ,atomic ,weights #f ,electricity #aa ,units of ,electricity #aa ,cathode ,rays #ac ,radioactivity #ag ,the ,structure of the ,atom #be ,atomic ,numbers #cj ,isotopes #ce ,energy #dg ,the ,law of ,conservation of ,energy #dg ,chemical ,energy #ej ,electrons and ,energy #ed ,the ,energy of the ,sun #ee ,the ,energy of ,radioactivity #eg ,,volume #b ,mass and ,energy #fi ,the ,structure of the ,nucleus #ge ,the ,proton #ge ,the ,proton-,electron ,theory #gf ,protons in ,nuclei #hj ,nuclear ,bombardment #hb ,particle ,accelerators #hf ,the ,neutron #ib ,nuclear ,spin #ib ,discovery of the ,neutron #ie ,the ,proton-,neutron ,theory #ih ,the ,nuclear ,interaction #aja ,neutron ,bombardment #ajg ,,volume #c ,nuclear ,fission #aag ,new ,elements #aag ,the ,discovery of ,fission #abb ,the ,nuclear ,chain ,reaction #abg ,the ,nuclear ,bomb #aca ,nuclear ,reactors #ada ,nuclear ,fusion #adf ,the ,energy of the ,sun #adf ,thermonuclear ,bombs #adh ,controlled ,fusion #aej ,beyond ,fusion #aeh ,antimatter #aeh ,the ,unknown #afc ,reading ,list #afe ,illustration3 ,enrico ,fermi 7left7 and ,niels ,bohr discuss physics as they stroll along the ,appian ,way outside ,rome in #aica4 ,,nuclear ,,fission ,new ,elements ,in #aicd ,enrico ,fermi began his first experiments involving the bombardment of uranium with neutrons--experiments that were to change the face of the world4 ,fermi had found that slow neutrons1 which had very little energy1 were easily absorbed by atomic nuclei--more easily than fast neutrons were absorbed1 and certainly more easily than charged particles were4 ,often what happened was that the neutron was simply absorbed by the nucleus4 ,since the neutron has a mass number of #a and an atomic number of #j 7because it is uncharged71 a nucleus that absorbs a neutron remains an isotope of the same element1 but increases its mass number4 ,for instance1 suppose that neutrons are used to bombard hydrogen-#a1 which then captures one of the neutrons4 ,from a single proton1 it will become a proton plus a neutron2 from hydrogen-#a1 it will become hydrogen-#b4 ,a new nucleus formed in this way will be at a higher energy and that energy is emitted in the form of a gamma ray4 ,sometimes the more massive isotope that is formed through neutron absorption is stable1 as hydrogen-#b is4 ,sometimes it is not1 but is radioactive instead4 ,because it has added a neutron1 it has too many neutrons for stability4 ,the best way of adjusting the matter is to emit a beta particle 7electron74 ,this converts one of the neutrons into a proton4 ,the mass number stays the same but the atomic number increases by one4 ,the element rhodium1 for example1 which has an atomic number of #de1 has only #a stable isotope1 with a mass number of #ajc4 ,if rhodium-#ajc 7#de protons1 #eh neutrons7 absorbs a neutron1 it becomes rhodium-#ajd 7#de protons1 #ei neutrons71 which is not stable4 ,rhodium-#ajd emits a beta particle1 changing a neutron to a proton so that the nuclear combination becomes #df protons and #eh neutrons4 ,this is palladium-#ajd1 which is stable4 ,illustration3 ,fermi's laboratory in ,rome in #aicj4 ,as another example1 indium-#aae 7#di protons1 #ff neutrons7 absorbs a neutron and becomes indium-#aaf 7#di protons1 #fg neutrons71 which gives off a beta particle and becomes tin-#aaf 7#ej protons1 #ff neutrons71 which is stable4 ,there are over #ajj isotopes that will absorb neutrons and end by becoming an isotope of an element one higher in the atomic number scale4 ,fermi observed a number of these cases4 ,having done so1 he was bound to ask what would happen if uranium were bombarded with neutrons4 ,would its isotopes also be raised in atomic number--in this case from #ib to #ic8 ,if that were so it would be very exciting1 for uranium had the highest atomic number in the entire scale4 ,nobody had ever discovered any sample of element number #ic1 but perhaps it could be formed in the laboratory4 ,in #aicd1 therefore1 ,fermi bombarded uranium with neutrons in the hope of obtaining atoms of element #ic4 ,neutrons were absorbed and whatever was formed did give off beta particles1 so element #ic should be there4 ,however1 four different kinds of beta particles 7different in their energy content7 were given off and the matter grew very confusing4 ,fermi could not definitely identify the presence of atoms of element #ic and neither could anyone else for several years4 ,other things turned up1 however1 which were even more significant4 ,before going on to these other things1 however1 it should be mentioned that undoubtedly element #ic was formed even though ,fermi couldn't clearly demonstrate the fact4 ,in #aici the ,american physicists ,edwin ,mattison ,mc,millan 7#aijg- 7 and ,philip ,hauge ,abelson 7#aiac- 71 after bombarding uranium atoms with slow neutrons1 were able to identify element #ic4 ,since uranium had originally been named for the planet1 ,uranus1 the new element beyond uranium was eventually named for the planet ,neptune1 which lay beyond ,uranus4 ,element #ic is therefore called 8neptunium04 ,illustration3 ,lise ,meitner ,illustration3 ,emilio ,segr ,illustration3 ,edwin ,m4 ,mc,millan ,illustration3 ,otto ,r4 ,frisch ,illustration3 ,glenn ,t4 ,seaborg ,illustration3 ,philip ,h4 ,abelson ,what happened was exactly what was expected4 ,uranium-#bch 7#ib protons1 #adf neutrons7 added a neutron to become uranium-#bci 7#ib protons1 #adg neutrons71 which emitted a beta particle to become neptunium-#bci 7#ic protons1 #adf neutrons74 ,in fact1 neptunium-#bci also emitted a beta particle so it ought to become an isotope of an element even higher in the atomic number scale4 ,this one1 element #id1 was named 8plutonium0 after ,pluto1 the planet beyond ,neptune4 ,the isotope1 plutonium-#bci1 formed from neptunium-#bci1 was only feebly radioactive1 however1 and it was not clearly identified until #aida4 ,the actual discovery of the element plutonium came the year before1 however1 when neptunium-#bch was formed4 ,it emitted a beta particle and became plutonium-#bch1 an isotope that was radioactive enough to be easily detected and identified by ,glenn ,theodore ,seaborg 7#aiab- 71 and his co-workers1 who completed ,mc,millan's experiments when he was called away to other defense research4 ,neptunium and plutonium were the first 8transuranium elements0 to be produced in the laboratory1 but they weren't the last4 ,over the next #cj years1 isotopes were formed that contained more and more protons in the nucleus and therefore had higher and higher atomic numbers4 ,at the moment of writing1 isotopes of every element up to and including element #aje have been formed4 ,a number of these new elements have been named for some of the scientists important in the history of nuclear research4 ,element #if is 8curium01 named for ,pierre and ,marie ,curie2 element #ii is 8einsteinium0 for ,albert ,einstein2 and element #ajj is 8fermium0 for ,enrico ,fermi4 ,element #aja is 8mendelevium0 for the ,russian chemist ,dmitri ,mendelev1 who early in #ahfi was the first to arrange the elements in a reasonable and useful order4 ,element #ajc is 8lawrencium0 for ,ernest ,o4 ,lawrence4 8,rutherfordium0 for ,ernest ,rutherford has been proposed for element #ajd4 ,and 8hahnium0 for ,otto ,hahn 7#ahgi-aifh71 a ,german physical chemist whose contribution we will come to shortly1 has been proposed for element #aje4 ,neptunium1 however1 was not the first new element to be created in the laboratory4 ,in the early #aicjs1 there were still #b elements with fairly low atomic numbers that had never been discovered4 ,these were the elements with atomic numbers #dc and #fa4 ,in #aicg1 though1 molybdenum 7atomic number #db7 had been bombarded with neutrons in ,lawrence's laboratory in the ,united ,states4 ,it might contain small quantities of element #dc as a result4 ,the ,italian physicist ,emilio ,segr 7#aije- 71 who had worked with ,fermi1 obtained a sample of the bombarded molybdenum and indeed obtained indications of the presence of element #dc4 ,it was the first new element to be manufactured by artificial means and was called 8technetium0 from the ,greek word for 8artificial04 ,the technetium isotope that was formed was radioactive4 ,indeed1 all the technetium isotopes are radioactive4 ,element #fa1 discovered in #aide and named 8promethium01 also has no stable isotopes4 ,technetium and promethium are the only elements with atomic numbers less than #hd that do not have even a single stable isotope4 ,the ,discovery of ,fission ,but let us get back to the bombardment of uranium with neutrons research that ,fermi had begun4 ,after he had reported his work1 other physicists repeated it and also got a variety of beta particles and were also unable to decide what was going on4 ,illustration3 ,lise ,meitner and ,otto ,hahn in their laboratory in the #aicjs4 ,one way to tackle the problem was to add to the system some stable element that was chemically similar to the tiny traces of radioactive isotopes that might be produced through the bombardment of uranium4 ,afterwards the stable element could probably be separated out of the mixture and the trace of radioactivity would1 it was hoped1 be carried along with it4 ,the stable element would be a 8carrier04 ,among those working on the problem were ,otto ,hahn and his ,austrian co-worker1 the physicist ,lise ,meitner 7#ahgh-aifh74 ,among the potential carriers they added to the system was the element1 barium1 which has an atomic number of #ef4 ,they found that a considerable quantity of the radioactivity did indeed accompany the barium when they separated that element out of the system4 ,a natural conclusion was that the isotopes producing the radioactivity belonged to an element that was chemically very similar to barium4 ,suspicion fell at once on radium 7atomic number #hh71 which was very like barium indeed as far as chemical properties were concerned4 ,lise ,meitner1 who was ,jewish1 found it difficult to work in ,germany1 however1 for it was then under the rule of the strongly anti-,semitic ,nazi regime4 ,in ,march #aich ,germany occupied ,austria1 which became part of the ,german realm4 ,meitner was no longer protected by her ,austrian citizenship and had to flee the country and go to ,stockholm1 ,sweden4 ,hahn remained in ,germany and continued working on the problem with the ,german physical chemist ,fritz ,strassman 7#aijb- 74 ,although the supposed radium1 which possessed the radioactivity1 was very like barium in chemical properties1 the two were not entirely identical4 ,there were ways of separating them1 and ,hahn and ,strassman busied themselves in trying to accomplish this in order to isolate the radioactive isotopes1 concentrate them1 and study them in detail4 ,over and over again1 however1 they failed to separate the barium and the supposed radium4 ,slowly1 it began to seem to ,hahn that the failure to separate the barium and the radioactivity meant that the isotopes to which the radioactivity belonged had to be so much like barium as to be nothing else but barium4 ,he hesitated to say so1 however1 because it seemed unbelievable4 ,if the radioactive isotopes included radium1 that was conceivable4 ,radium had an atomic number of #hh1 only four less than uranium's #ib4 ,you could imagine that a neutron being absorbed by a uranium nucleus might make the latter so unstable as to cause it to emit #b alpha particles and become radium4 ,barium1 however1 had an atomic number of #ef1 only a little over half that of uranium4 ,how could a uranium nucleus be made to turn into a barium nucleus unless it more or less broke in half8 ,nothing like that had ever been observed before and ,hahn hesitated to suggest it4 ,while he was nerving himself to do so1 however1 ,lise ,meitner1 in ,stockholm1 receiving reports of what was being done in ,hahn's laboratory and thinking about it1 decided that unheard-of or not1 there was only one explanation4 ,the uranium nucleus was breaking in half4 ,actually1 when one stopped to think of it 7after getting over the initial shock7 it wasn't so unbelievable at that4 ,the nuclear force is so short-range1 it barely reaches from end to end of a large nucleus like that of uranium4 ,left to itself1 it holds together most of the time1 but with the added energy of an entering neutron1 we might imagine shock waves going through it and turning the nucleus into something like a quivering drop of liquid4 ,sometimes the uranium nucleus recovers1 keeps the neutron1 and then goes on to beta-particle emission4 ,and sometimes the nucleus stretches to the point where the nuclear force doesn't quite hold it together4 ,it becomes a dumbbell shape and then the electromagnetic repulsion of the two halves 7both positively charged7 breaks it apart altogether4 ,it doesn't break into equal halves4 ,nor does it always break at exactly the same place1 so that there were a number of different fragments possible 7which was why there was so much confusion74 ,still1 one of the more common ways in which it might break would be into barium and krypton4 7,their respective atomic numbers1 #ef and #cf1 would add up to #ib47 ,meitner and her nephew1 ,otto ,robert ,frisch 7#aijd- 71 who was in ,copenhagen1 ,denmark1 prepared a paper suggesting that this was what was happening4 ,it was published in ,january #aici4 ,frisch passed it on to the ,danish physicist ,niels ,bohr 7#ahhe-aifb7 with whom he was working4 ,the ,american biologist ,william ,archibald ,arnold 7#aijd- 71 who was also working in ,copenhagen at the time1 suggested that the splitting of the uranium nucleus into halves be called 8fission01 the term used for the division-in-two of living cells4 ,the name stuck4 ,in ,january #aici1 just about the time ,meitner and ,frisch's paper was published1 ,bohr had arrived in the ,united ,states to attend a conference of physicists4 ,he carried the news of fission with him4 ,the other physicists attending the conference heard the news and in a high state of excitement at once set about studying the problem4 ,within a matter of weeks1 the fact of uranium fission was confirmed over and over4 ,one striking fact about uranium fission was the large amount of energy it released4 ,in general1 when a very massive nucleus is converted to a less massive one1 energy is released because of the change in the mass defect1 as ,aston had shown in the #aibjs4 ,when the uranium nucleus breaks down through the ordinary radioactive processes to become a less massive lead nucleus1 energy is given off accordingly4 ,when1 however1 it breaks in two to become the much less massive nuclei of barium and krypton 7or others in that neighborhood7 much more energy is given off4 ,it quickly turned out that uranium fission gave off something like ten times as much nuclear energy per nucleus than did any other nuclear reaction known at the time4 ,even so1 the quantity of energy released by uranium fission was only a tiny fraction of the energy that went into the preparation of the neutrons used to bring about the fission1 if each neutron that struck a uranium atom brought about a single fission of that #a atom4 ,under those conditions1 ,rutherford's suspicion that mankind would never be able to tap nuclear energy probably still remained true4 7,he had been dead for #b years at the time of the discovery of fission47 ,however1 those were not the conditions4 ,the ,nuclear ,chain ,reaction ,earlier in this history1 we discussed chain reactions involving chemical energy4 ,a small bit of energy can ignite a chemical reaction that would produce more than enough energy to ignite a neighboring section of the system1 which would in turn produce still more--and so on1 and so on4 ,in this way the flame of a single match could start a fire in a leaf that would burn down an entire forest1 and the energy given off by the burning forest would be enormously higher than the initial energy of the match flame4 ,might there not be such a thing as a 8nuclear chain reaction08 ,could one initiate a nuclear reaction that would produce something that would initiate more of the same that would produce something that would initiate still more of the same and so on8 ,in that case1 a nuclear reaction1 once started1 would continue of its own accord1 and in return for the trifling investment that would serve to start it--a single neutron1 perhaps--a vast amount of breakdowns would result with the delivery of a vast amount of energy4 ,even if it were necessary to expend quite a bit of energy to produce the #a neutron that would start the chain reaction1 one would end with an enormous profit4 ,what's more1 since the nuclear reaction would spread from nucleus to nucleus with millionths-of-a-second intervals1 there would be1 in a very brief time1 so many nuclei breaking down that there would be a vast explosion4 ,the explosion was sure to be millions of times as powerful as ordinary chemical explosions involving the same quantity of exploding material1 since the latter used only the electromagnetic interaction1 while the former used the much stronger nuclear interaction4 ,the first to think seriously of such a nuclear chain reaction was the ,hungarian physicist ,leo ,szilard 7#ahih-aifd74 ,he was working in ,germany in #aicc when ,adolf ,hitler came to power and1 since he was ,jewish1 he felt it would be wise to leave ,germany4 ,he went to ,great ,britain and there1 in #aicd1 he considered certain new types of nuclear reactions that had been discovered4 ,in these1 it sometimes happened that a fast neutron might strike a nucleus with sufficient energy to cause it to emit #b neutrons4 ,in that way the nucleus1 absorbing #a neutron and emitting #b1 would become a lighter isotope of the same element4 ,but what would happen if each of the #b neutrons that emerged from the original target nucleus struck new nuclei and forced the emission of a pair of neutrons from each4 ,there would now be a total of #d neutrons flying about and if each struck new nuclei there would next be #h neutrons and so on4 ,from the initial investment of a single neutron there might soon be countless billions initiating nuclear reactions4 ,szilard1 fearing the inevitability of war and fearing further that the brutal leaders of ,germany might seek and use such a nuclear chain reaction as a weapon in warfare1 secretly applied for a patent on a device intending to make use of such a nuclear chain reaction4 ,he hoped to turn it over to the ,british ,government1 which might then use its possession as a way of restraining the ,nazis and keeping the peace4 ,however1 it wouldn't have worked4 ,it took the impact of a very energetic neutron to bring about the emission of #b neutrons4 ,the neutrons that then emerged from the nucleus simply didn't have enough energy to keep things going4 7,it was like trying to make wet wood catch fire47 ,but what about uranium fission8 ,uranium fission was initiated by slow neutrons4 ,what if uranium fission also produced neutrons as well as being initiated by a neutron8 ,would not the neutrons produced serve to initiate new fissions that would produce new neutrons and so on endlessly8 ,it seemed very likely that fission produced neutrons and indeed1 ,fermi1 at the conference where fission was first discussed1 suggested it at once4 ,massive nuclei possessed more neutrons per proton than less massive ones did4 ,if a massive nucleus was broken up into #b considerably less massive ones1 there would be a surplus of neutrons4 ,suppose1 for instance1 uranium-#bch broke down into barium-#ach and krypton-#hf4 ,barium-#ach contains #hb neutrons and krypton-#hf #ej neutrons for a total of #acb4 ,the uranium-#bch nucleus1 however1 contains #adf neutrons4 ,the uranium fission process was studied at once to see if neutrons were actually given off and a number of different physicists1 including ,szilard1 found that they were4 ,now ,szilard was faced with a nuclear chain reaction he was certain would work4 ,only slow neutrons were involved and the individual nuclear breakdowns were far more energetic than anything else that had yet been discovered4 ,if a chain reaction could be started in a sizable piece of uranium1 unimaginable quantities of energy would be produced4 ,just #a gram of uranium1 undergoing complete fission1 would deliver the energy derived from the total burning of #c tons of coal and would deliver that energy in a tiny fraction of a second4 ,szilard1 who had come to the ,united ,states in #aicg1 clearly visualized the tremendous explosive force of something that would have to be called a 8nuclear bomb04 ,szilard dreaded the possibility that ,hitler might obtain the use of such a bomb through the agency of ,germany's nuclear scientists4 ,partly through ,szilard's efforts1 physicists in the ,united ,states and in other ,western nations opposed to ,hitler began a program of voluntary secrecy in #aidj1 to avoid passing along any hints to ,germany4 ,what's more1 ,szilard enlisted the services of two other ,hungarian refugees1 the physicists ,eugene ,paul ,wigner 7#aijb- 7 and ,edward ,teller 7#aijh- 7 and all approached ,einstein1 who had also fled ,germany and come to ,america4 ,illustration3 ,leo ,szilard ,illustration3 ,eugene ,p4 ,wigner ,einstein was the most prestigious scientist then living and it was thought a letter from him to the ,president of the ,united ,states would be most persuasive4 ,einstein signed such a letter1 which explained the possibility of a nuclear bomb and urged that the ,united ,states not allow a potential enemy to come into possession of it first4 ,largely as a result of this letter1 a huge research team was put together in the ,united ,states1 to which other ,western nations also contributed1 with but one aim--to develop the nuclear bomb4 ,the ,nuclear ,bomb ,although the theory of the nuclear bomb seemed clear and simple1 a great many practical difficulties stood in the way4 ,in the first place1 if only uranium atoms underwent fission a supply of uranium had at least to be obtained in pure form1 for if the neutrons struck nuclei of elements other than uranium1 they would simply be absorbed and removed from the system1 ending the possibility of a chain reaction4 ,this alone was a heavy task1 since there had been so little use for uranium in quantity that there was almost no supply in existence and no experience in how to purify it4 ,secondly1 the supply of uranium might have to be a large one1 for neutrons didn't necessarily enter the first uranium atom they approached4 ,they moved about here and there1 making glancing collisions1 and travelling quite a distance1 perhaps1 before striking head-on and entering a nucleus4 ,if in that time they had passed outside the lump of uranium1 they were useless4 ,illustration3 ,franklin ,d4 ,roosevelt ,albert ,einstein ,old ,grove ,rd4 ,nassau ,point ,peconic1 ,long ,island ,august #bnd1 #aici ,f4,d4 ,roosevelt1 ,president of the ,united ,states1 ,white ,house ,washington1 ,d4,c4 ,sir3 ,some recent work by ,e4 ,fermi and ,l4 ,szilard1 which has been communicated to me in manuscript1 leads me to expect that the element uranium may be turned into a new and important source of energy in the immediate future4 ,certain aspects of the situation which has arisen seem to call for watchfulness and1 if necessary1 quick action on the part of the ,administration4 ,i believe therefore that it is my duty to bring to your attention the following facts and recommendations3 ,in the course of the last four months it has been made probable--through the work of ,joliot in ,france as well as ,fermi and ,szilard in ,america--that it may become possible to set up a nuclear chain reaction in a large mass of uranium1 by which vast amounts of power and large quantities of new radium-like elements would be generated4 ,now it appears almost certain that this could be achieved in the immediate future4 ,this new phenomenon would also lead to the construction of bombs1 and it is conceivable--though much less certain--that extremely powerful bombs of a new type may thus be constructed4 ,a single bomb of this type1 carried by boat and exploded in a port1 might very well destroy the whole port together with some of the surrounding territory4 ,however1 such bombs might very well prove to be too heavy for transportation by air4 ,illustration3 ,albert ,einstein ,the ,united ,states has only very poor ores of uranium in moderate quantities4 ,there is some good ore in ,canada and the former ,czechoslovakia1 while the most important source of uranium is ,belgian ,congo4 ,in view of this situation you may think it desirable to have some permanent contact maintained between the ,administration and the group of physicists working on chain reactions in ,america4 ,one possible way of achieving this might be for you to entrust with this task a person who has your confidence and who could perhaps serve in an inofficial capacity4 ,his task might comprise the following3 a7 to approach ,government ,departments1 keep them informed of the further development1 and put forward recommendations for ,government action1 giving particular attention to the problem of securing a supply of uranium ore for the ,united ,states2 b7 to speed up the experimental work1 which is at present being carried on within the limits of the budgets of ,university laboratories1 by providing funds1 if such funds be required1 through his contacts with private persons who are willing to make contributions for this cause1 and perhaps also by obtaining the co-operation of industrial laboratories which have the necessary equipment4 ,i understand that ,germany has actually stopped the sale of uranium from the ,czechoslovakian mines which she has taken over4 ,that she should have taken such early action might perhaps be understood on the ground that the son of the ,german ,under-,secretary of ,state1 von ,weizscker1 is attached to the ,kaiser-,wilhelm-,institut in ,berlin where some of the ,american work on uranium is now being repeated4 ,yours very truly1 ,illustration3 _/signed_/ 7,albert ,einstein7 ,as the quantity of uranium within which the fission chain reaction was initiated grew larger1 more and more of the neutrons produced found a mark and the fission reaction would die out more and more slowly4 ,finally1 at some particular size--the 8critical size0--the fission reaction did not die at all1 but maintained itself1 with enough of the neutrons produced finding their mark to keep the nuclear reaction proceeding at a steady rate4 ,at any greater size the nuclear reaction would accelerate and there would be an explosion4 ,it wasn't even necessary to send neutrons into the uranium to start the process4 ,in #aida the ,russian physicist ,georgii ,nikolaevich ,flerov 7#aiac- 7 found that every once in a while a uranium atom would undergo fission without the introduction of a neutron4 ,occasionally the random quivering of a nucleus would bring about a shape that the nuclear interaction could not bring back to normal and the nucleus would then break apart4 ,in a gram of ordinary uranium1 there is a nucleus undergoing such 8spontaneous fission0 every #b minutes on the average4 ,therefore1 enough uranium need only be brought together to surpass critical size and it will explode within seconds1 for the first nucleus that undergoes spontaneous fission will start the chain reaction4 ,first estimates made it seem that the quantity of uranium needed to reach critical size was extraordinarily great4 ,fully #ii4c of the metal is uranium-#bch1 however1 and1 as soon as fission was discovered1 ,bohr pointed out that there were theoretical reasons for supposing that it was the uranium-#bce isotope 7making up only #j4g of the whole7 that was the one undergoing fission4 ,investigation proved him right4 ,indeed1 the uranium-#bch nucleus tended to absorb slow neutrons without fission1 and to go on to beta-particle production that formed isotopes of neptunium and plutonium4 ,in this way uranium-#bch actually interfered with the chain reaction4 ,in any quantity of uranium1 the more uranium-#bce present and the less uranium-#bch1 the more easily the chain reaction would proceed and the lower the critical size needed4 ,vast efforts were therefore made to separate the #b isotopes and prepare uranium with a higher than normal concentration of uranium-#bce 78enriched uranium074 ,of course1 there was no great desire for a fearful explosion to get out of hand while the chain reaction was being studied4 ,before any bomb could be constructed1 the mechanism of the chain reaction would have to be studied4 ,could a chain reaction capable of producing energy 7for useful purposes as well as for bombs7 be established8 ,to test this1 a quantity of uranium was gathered in the hope that a controlled chain reaction of uranium fission could be established4 ,for that purpose1 control rods of a substance that would easily absorb neutrons and slow the chain reaction were used4 ,the metal1 cadmium1 served admirably for this purpose4 ,then1 too1 the neutrons released by fission were pretty energetic4 ,they tended to travel too far too soon and get outside the lump of uranium too easily4 ,to produce a chain reaction that could be studied with some safety1 the presence of a moderator was needed4 ,this was a supply of small nuclei that did not absorb neutrons readily1 but absorbed some of the energy of collision and slowed down any neutron that struck it4 ,nuclei such as hydrogen-#b1 beryllium-#i1 or carbon-#ab were useful moderators4 ,when the neutrons produced by fission were slowed1 they travelled a smaller distance before being absorbed in their turn and the critical size would again be reduced4 ,toward the end of #aidb the initial stage of the project reached a climax4 ,blocks of graphite containing uranium metal and uranium oxide were piled up in huge quantities 7enriched uranium was not yet available7 in order to approach critical size4 ,this took place under the stands of a football stadium at the ,university of ,chicago1 with ,enrico ,fermi 7who had come to the ,united ,states in #aich7 in charge4#a ,the large structure was called an 8atomic pile0 at first because of the blocks of graphite being piled up4 ,the proper name for such a device1 and the one that was eventually adopted1 was1 however1 8nuclear reactor04 ,on ,december #b1 #aidb1 calculations showed that the nuclear reactor was large enough to have reached critical size4 ,the only thing preventing the chain reaction from sustaining itself was the cadmium rods that were inserted here and there in the pile and that were soaking up neutrons4 ,illustration3 ,cutaway model of the ,west ,stands of ,stagg ,field showing the first pile in the squash court beneath it4 ,illustration3 ,the exterior of the building4 ,illustration3 ,graphite layers form the base of the pile1 left4 ,on the right is the seventh layer of graphite and edges of the sixth layer containing #c-;inch pseudospheres of black uranium oxide4 ,beginning with layer #f1 alternate courses of graphite containing uranium metal and_/or uranium oxide fuel were separated by layers of solid graphite blocks4 ,illustration3 ,tenth layer of graphite blocks containing pseudospheres of black and brown uranium oxide4 ,the brown briquets1 slightly richer in uranium1 were concentrated in the central area4 ,on the right is the nineteenth layer of graphite covering layer #ah containing slugs of uranium oxide4 ,one by one the cadmium rods were pulled out4 ,the number of uranium atoms undergoing fission each second rose and1 finally1 at #c3de p4m41 the uranium fission became self-sustaining4 ,it kept going on its own 7with the cadmium rods ready to be pushed in if it looked as though it were getting out of hand--something calculations showed was not likely74 ,news of this success was announced to ,washington by a cautious telephone call from ,arthur ,holly ,compton 7#ahib-aifb7 to ,james ,bryant ,conant 7#ahic- 74 8,the ,italian navigator has landed in the new world01 said ,compton4 ,conant asked1 8,how were the natives801 and the answer was1 8,very friendly04 ,this was the day and moment when the world entered the 8nuclear age04 ,for the first time1 mankind had constructed a device in which the nuclear energy being given off was greater than the energy poured in4 ,mankind had tapped the reservoirs of nuclear energy and could put it to use4 ,had ,rutherford lived but #f more years1 he would have seen how wrong he was to think it could never be done4 ,the people of earth remained unaware of what had taken place in ,chicago and physicists continued to work toward the development of the nuclear bomb4 ,enriched uranium was successfully prepared4 ,critical sizes were brought low enough to make a nuclear bomb small enough to be carried by plane to some target4 ,suppose one had #b slabs of enriched uranium1 each below critical size1 but which were above critical size if combined4 ,and suppose an explosive device were added that1 at some desired moment1 could be set off in such a way that it would drive #a slab of enriched uranium against the other4 ,there would be an instant explosion of devastating power4 ,or suppose the enriched uranium were arranged in loosely packed pieces to begin with so that the flying neutrons were in open air too often to maintain the chain reaction4 ,a properly arranged explosion might compress the uranium into a dense ball4 ,neutron absorption would become more efficient and again1 an explosion would follow4 ,illustration3 ,nuclear ,fission of ,uranium3 ,a neutron hits the nucleus of an atom of uranium4 ,the neutron splits the nucleus into two parts and creates huge amounts of energy in the form of heat4 ,at the same time other neutrons are released from the splitting nucleus and these continue the fission process in a chain reaction4 ,on ,july #af1 #aide1 a device that would result in a nuclear explosion was set up near ,alamogordo1 ,new ,mexico1 with nervous physicists watching from a safe distance4 ,it worked perfectly2 the explosion was tremendous4 ,by that time ,nazi ,germany had been defeated1 but ,japan was still fighting4 ,two more devices were prepared4 ,after a warning1 one was exploded over the ,japanese city of ,hiroshima on ,august #f1 #aide1 and the other over ,nagasaki #b days later4 ,the ,japanese government surrendered and ,world ,war ,,ii came to an end4 ,it was with the blast over ,hiroshima that the world came to know it was in the nuclear age and that the ferocious weapon of the nuclear bomb existed4 7,the popular name for it at the time was 8atomic bomb0 or 8,a-bomb047 ,during the war1 ,german scientists may have been trying to develop a nuclear bomb1 but1 if so1 they had not yet succeeded at the time ,germany met its final defeat4 ,soviet physicists1 under ,igor ,vasilievich ,kurchatov 7#aijc-aifj71 were also working on the problem4 ,the dislocation of the war1 which inflicted much more damage on the ,soviet ,union than on the ,united ,states1 kept the ,soviet effort from succeeding while it was on4 ,however1 since the ,soviets were among the victors1 they were able to continue after the war4 ,in #aidi the ,soviets exploded their first nuclear bomb4 ,in #aieb the ,british did the same2 in #aifj1 the ,french2 and in #aifd1 the ,chinese4 ,although many nuclear bombs have been exploded for test purposes1 the two over ,hiroshima and ,nagasaki have been the only ones used in time of war4 ,nor need nuclear bombs be considered as having destructive potential only4 ,there is the possibility that1 with proper precautions1 they might be used to make excavations1 blast out harbors or canals1 break up underground rock formations to recover oil or other resources1 and in other ways do the work of chemical explosives with far greater speed and economy4 ,it has even been suggested that a series of nuclear bomb explosions might be used to hurl space vehicles forward in voyages away from earth4 ,nuclear ,reactors ,the development of the nuclear chain reaction was not in the direction of bombs only4 ,nuclear reactors designed for the controlled production of useful energy multiplied in number and in efficiency since ,fermi's first 8pile04 ,many nations now possess them1 and they are used for a variety of purposes4#b ,illustration3 ,the ,,uss ,nautilus1 the world's first nuclear powered submarine1 in ,new ,york harbor4 ,in #aied the first nuclear submarine the ,,uss ,nautilus was launched by the ,united ,states4 ,its power was obtained entirely from a nuclear reactor1 and it was not necessary for it to rise to the surface at short intervals in order to recharge its batteries4 ,nuclear submarines have crossed the ,arctic ,ocean under the ice cover1 and have circumnavigated the globe without surfacing4 ,in #aiei both the ,soviet ,union and the ,united ,states launched nuclear-powered surface vessels4 ,the ,soviet ship was the icebreaker1 ,lenin1 and the ,american ship was a merchant vessel1 the ,,ns ,savannah4 ,in the #aiejs nuclear reactors were also used as the source of power for the production of electricity for civilian use4 ,the ,soviet ,union built a small station of this sort in #aied1 which had a capacity of #e1jjj kilowatts4 ,the ,british built one of #ib1jjj kilowatt capacity1 which they called ,calder ,hall4 ,the first ,american nuclear reactor for civilian use began operation at ,shippingport1 ,pennsylvania1 in #aieh4 ,it was the first really full-scale civilian nuclear power plant in the world4 ,the world appeared to have far greater sources of energy than had been expected4 ,the 8fossil fuels0--coal1 oil and natural gas--were being used at such a rate that many speculated that the gas and oil would be gone in decades and the coal in centuries4 ,was it possible that uranium might now serve as a new source that would last indefinitely8 ,it was rather disappointing that it was uranium-#bce which underwent fission1 because that isotope made up only #j4g of the uranium that existed4 ,if uranium-#bce were all we had and all we ever could have1 the energy supply of the world would still be rather too limited4 ,there were other possible 8nuclear fuels01 however4 ,there was plutonium-#bci1 which would also fission under neutron bombardment4 ,it had an ordinary half-life 7for a radioactive change in which it gave off alpha particles7 of #bd1cjj years1 which is long enough to make it easy to handle4 ,but how can plutonium-#bci be formed in sufficient quantities to be useful8 ,after all1 it doesn't occur in nature4 ,surprisingly1 that turned out to be easy4 ,uranium-#bch atoms will absorb many of the neutrons that are constantly leaking out of the reactor and will become first neptunium-#bci and then plutonium-#bci4 ,the plutonium1 being a different element from the uranium1 can be separated from uranium and obtained in useful quantities4 ,such a device is called a 8breeder reactor0 because it breeds fuel4 ,indeed1 it can be so designed to produce more plutonium-#bci than the uranium-#bce it uses up1 so that you actually end up with more nuclear fuel than you started with4 ,in this way1 all the uranium on earth 7and not just uranium-#bce7 can be considered potential nuclear fuel4 ,illustration3 ,the ,shippingport ,atomic ,power ,station1 the first full-scale1 nuclear-electric station built exclusively for civilian needs1 provides electricity for the homes and factories of the greater ,pittsburgh area4 ,the pressurized-water reactor1 which now has a #ij1jjj-net-electrical-kilowatt capacity1 began commercial operation in #aieg4 ,the reactor is in the large building in the center4 ,illustration3 ,the lights of downtown ,pittsburgh4 ,the first breeder reactor was completed at ,arco1 ,idaho1 in ,august #aiea1 and on ,december #bj produced the very first electricity on earth to come from nuclear power4 ,nevertheless1 breeder reactors for commercial use are still a matter for the future4#c ,another isotope capable of fissioning under neutron bombardment is uranium-#bcc4 ,it does not occur in nature1 but was formed in the laboratory by ,seaborg and others in #aidb4 ,it has a half-life of #afb1jjj years4 ,it can be formed from naturally occurring thorium-#bcb4 ,thorium-#bcb will absorb a neutron to become thorium-#bcc4 ,then #b beta particles are given off so that the thorium-#bcc becomes first protactinium-#bcc and then uranium-#bcc4 ,if a thorium shell surrounds a nuclear reactor1 fissionable uranium-#bcc is formed within it and is easily separated from the thorium4 ,in this way1 thorium is also added to the list of earth's potential nuclear fuels4#d ,if all the uranium and thorium in the earth's crust 7including the thin scattering of those elements through granite1 for instance7 were available for use1 we might get up to #ajj times as much energy from it as from all the coal and oil on the planet4 ,unfortunately1 it is very unlikely that we will ever be able to make use of all the uranium and thorium4 ,it is widely and thinly spread through the crustal rocks and much of it could not be extracted without using up more energy than would be supplied by it once isolated4 ,another problem rests with the nature of the fission reaction4 ,when the uranium-#bce nucleus 7or plutonium-#bci or uranium-#bcc7 undergoes fission1 it breaks up into any of a large number of middle-sized nuclei that are radioactive--much more intensely radioactive than the original fuel4 7,it was from among these 8fission products0 that isotopes of element #fa were first obtained in #aide4 ,coming from the nuclear fire1 it reminded its discoverers of ,prometheus1 who stole fire from the sun in the ,greek myths1 and so it was called 8promethium047 ,the fission products still contain energy and some of them can be used in lightweight 8nuclear batteries04 ,such nuclear batteries were first built in #aied4 ,some batteries1 using plutonium-#bch rather than fission products1 have been put to use in powering artificial satellites over long periods4 ,unfortunately1 only a small proportion of the fission products can be put to profitable use4 ,most must be disposed of4 ,they are dangerous because the radiations they give off are deadly and cannot be detected by the ordinary senses4 ,they are very difficult to dispose of safely1 and they must not be allowed to get into the environment1 especially since some of them remain dangerous for decades or even centuries4 ,illustration3 ,the ,experimental ,breeder ,reactor ,no4 #b building complex in ,idaho4 ,the reactor is in the dome-shaped structure4 ,,nuclear ,,fusion ,the ,energy of the ,sun ,as it happens1 though1 nuclear fission is not the only route to useful nuclear energy4 ,aston's studies in the #aibjs had shown that it was the middle-sized nuclei that were most tightly packed4 ,energy would be given off if middle-sized nuclei were produced from either extreme4 ,not only would energy be formed by the breakup of particularly massive nuclei through fission1 but also through the combination of small nuclei to form larger ones 78nuclear fusion074 ,in fact1 from ,aston's studies it could be seen that1 mass for mass1 nuclear fusion would produce far more energy than nuclear fission4 ,this was particularly true in the conversion of hydrogen to helium2 that is1 the conversion of the individual protons of #d separate hydrogen nuclei into the #b-proton--#b-neutron structure of the helium nucleus4 ,a gram of hydrogen1 undergoing fusion to helium1 would deliver some fifteen times as much energy as a gram of uranium undergoing fission4 ,as early as #aibj1 the ,english astronomer ,arthur ,stanley ,eddington 7#ahhb-aidd7 had speculated that the sun's energy might be derived from the interaction of subatomic particles4 ,some sort of nuclear reaction seemed1 by then1 to be the most reasonable way of accounting for the vast energies constantly being produced by the sun4 ,the speculation became more plausible with each year4 ,eddington himself studied the structure of stars1 and by #aibf had produced convincing theoretical reasons for supposing that the center of the sun was at enormous densities and temperatures4 ,a temperature of some #ae1jjj1jjj to #bj1jjj1jjj;,c seemed to characterize the sun's center4 ,at such temperatures1 atoms could not exist in earthly fashion4 ,held together by the sun's strong gravitational field1 they collided with such energy that all or almost all their electrons were stripped off1 and little more than bare nuclei were left4 ,these bare nuclei could approach each other much more closely than whole atoms could 7which was why the center of the sun was so much more dense than earthly matter could be74 ,the bare nuclei1 smashing together at central-sun temperatures1 could cling together and form more complex nuclei4 ,nuclear reactions brought about by such intense heat 7millions of degrees7 are called 8thermonuclear reactions04 ,as the #aibjs progressed further studies of the chemical structure of the sun showed it to be even richer in hydrogen than had been thought4 ,in #aibi the ,american astronomer ,henry ,norris ,russell 7#ahgg-aieg7 reported evidence that the sun was #fj hydrogen in volume4 7,even this was too conservative2 #hj is considered more nearly correct now47 ,if the sun's energy were based on nuclear reactions at all1 then it had to be the result of hydrogen fusion4 ,nothing else was present in sufficient quantity to be useful as a fuel4 ,more and more was learned about the exact manner in which nuclei interacted and about the quantity of energy given off in particular nuclear reactions4 ,it became possible to calculate what might be going on inside the sun by considering the densities and temperatures present1 the kind and number of different nuclei available1 and the quantity of energy that must be produced4 ,in #aich the ,german-,american physicist ,hans ,albrecht ,bethe 7#aijf- 7 and the ,german astronomer ,carl ,friedrich von ,weizscker 7#aiab- 7 independently worked out the possible reactions1 and hydrogen fusion was shown to be a thoroughly practical way of keeping the sun going4 ,thanks to the high rate of energy production by thermonuclear reactions and to the vast quantity of hydrogen in the sun1 not only has it been possible for the sun to have been radiating energy for the last #e1jjj1jjj1jjj years or so1 but it will continue to radiate energy in the present fashion for at least #e1jjj1jjj1jjj years into the future4 ,illustration3 ,hans ,bethe ,even so1 the sheer quantity of what is going on in the sun is staggering in earthly terms4 ,in the sun #fej1jjj1jjj tons of hydrogen are converted into helium every second1 and in the process each second sees the disappearance of #d1fjj1jjj tons of mass4 ,thermonuclear ,bombs ,could thermonuclear reactions be made to take place on earth8 ,the conditions that exist in the center of the sun would be extremely difficult to duplicate on the earth1 so there was a natural search for any kind of nuclear fusion that would produce similar energies to those going on in the sun but which would be easier to bring about4 ,there are #c hydrogen isotopes known to exist4 ,ordinary hydrogen is almost entirely hydrogen-#a1 with a nucleus made up of a single proton4 ,small quantities of hydrogen-#b 7deuterium7 with a nucleus made up of a proton plus a neutron also exist and such atoms are perfectly stable4 ,in #aicd ,rutherford1 along with the ,australian physicist ,marcus ,laurence ,elwin ,oliphant 7#aija- 7 and the ,austrian chemist ,paul ,harteck 7#aijb- 7 sent hydrogen-#b nuclei flying into hydrogen-#b targets and formed hydrogen-#c 7also called 8tritium0 from the ,greek word for 8third07 with a nucleus made up of a proton plus #b neutrons4 ,hydrogen-#c is mildly radioactive4 ,hydrogen-#b fuses to helium more easily than hydrogen-#a does and1 all things being equal1 hydrogen-#b will do so at lower temperatures than hydrogen-#a4 ,hydrogen-#c requires lower temperatures still4 ,but even for hydrogen-#c it still takes millions of degrees4 ,hydrogen-#c1 although the easiest to be forced to undergo fusion1 exists only in tiny quantities4 ,hydrogen-#b1 therefore1 is the one to pin hopes on especially in conjunction with hydrogen-#c4 ,only #a atom out of every #fjjj hydrogen atoms is hydrogen-#b1 but that is enough4 ,there exists a vast ocean on earth that is made up almost entirely of water molecules and in each water molecule #b hydrogen atoms are present4 ,even if only #a in #fjjj of these hydrogen atoms is deuterium that still means there are about #ce1jjj billion tons of deuterium in the ocean4 ,what's more1 it isn't necessary to dig for that deuterium or to drill for it4 ,if ocean water is allowed to run through separation plants1 the deuterium can be extracted without very much trouble4 ,in fact1 for the energy you could get out of it1 deuterium from the oceans1 extracted by present methods and without allowing for future improvement1 would be only one-hundredth as expensive as coal4 ,the deuterium in the world's ocean1 if allowed to undergo fusion little by little1 would supply mankind with enough energy to keep us going at the present rate for #ejj1jjj1jjj1jjj years4 ,to be sure1 to make deuterium fusion practical1 it may be necessary to make use of rarer substances such as the light metal lithium4 ,this will place a sharper limit on the energy supply but even if we are careful1 fusion would probably supply mankind with energy for as long as mankind will exist4 ,then1 too1 there would seem to be no danger of hydrogen fusion plants running out of control4 ,only small quantities of deuterium would be in the process of fusion at any one time4 ,if anything at all went wrong1 the deuterium supply could be automatically cut off and the fusion process1 with so little involved1 would then stop instantly4 ,moreover1 there would be less reason to worry about atomic wastes1 for the most dangerous products--hydrogen-#c and neutrons--could be easily taken care of4 ,it seems ideal1 but there is a catch4 ,however clear the theory1 before a fusion power station can be established some practical method must be found to start the fusion process1 which means finding some way for attaining temperatures in the millions of degrees4 ,one method for obtaining the necessary temperature was known by #aide4 ,an exploding fission bomb would do it4 ,if1 somehow1 the necessary hydrogen-#b was combined with a fission bomb1 the explosion would set off a fusion reaction that would greatly multiply the energy released4 ,you would have in effect a 8thermonuclear bomb04 7,to the general public1 this was commonly known as a 8hydrogen bomb0 or an 8,h-bomb047 ,in #aieb the first fusion device was exploded by the ,united ,states in the ,marshall ,islands4 ,within months1 the ,soviet ,union had exploded one of its own and in time thermonuclear bombs thousands of times as powerful as the first fission bomb over ,hiroshima were built and exploded4 ,all thermonuclear bombs have been exploded only for test purposes4 ,even testing seems to be dangerous1 however1 at least if it is carried on in the open atmosphere4 ,the radioactivity liberated spreads over the world and may do slow but cumulative damage4 ,controlled ,fusion ,however effective a fusion bomb may be in liberating vast quantities of energy1 it is not what one has in mind when speaking of a fusion power station4 ,the energy of a fusion bomb is released all at once and its only function is that of utter destruction4 ,what is wanted is the production of fusion energy at a low and steady rate--a rate that is under the control of human operators4 ,the sun1 for instance1 is a vast fusion furnace #hff1jjj miles across1 but it is a controlled one--even though that control is exerted by the impersonal laws of nature4 ,it releases energy at a very steady and very slow rate4 7,the rate is not slow in human terms1 of course1 but stars sometimes do release their energy in a much more cataclysmic fashion4 ,the result is a 8supernova0 in which for a short time a single star will increase its radiation to as much as a trillion times its normal level47 ,the sun 7or any star7 going at its normal rate is controlled and steady in its output because of the advantage of huge mass4 ,an enormous mass1 composed mainly of hydrogen1 compresses itself1 through its equally enormous gravitational field1 into huge densities and temperatures at its center1 thus igniting the fusion reaction--while the same gravitational field keeps the sun together against its tendency to expand4 ,there is1 as far as scientists know1 no conceivable way of concentrating a high gravitational field in the absence of the required mass1 and the creation of controlled fusion on earth must therefore be done without the aid of gravity4 ,without a huge gravitational force we cannot simultaneously bring about sun-center densities and sun-center temperatures2 one or the other must go4 ,on the whole1 it would take much less energy to aim at the temperatures than at the densities and would be much more feasible4 ,for this reason1 physicists have been attempting1 all through the nuclear age1 to heat thin wisps of hydrogen to enormous temperature4 ,since the gas is thin1 the nuclei are farther apart and collide with each other far fewer times per second4 ,to achieve fusion ignition1 therefore1 temperatures must be considerably higher than those at the center of the sun4 ,in #aidd ,fermi calculated that it might take a temperature of #ej1jjj1jjj to ignite a hydrogen-#c fusion with hydrogen-#b under earthly conditions1 and #djj1jjj1jjj to ignite hydrogen-#b fusion alone4 ,to ignite hydrogen-#a fusion1 which is what goes on in the sun 7at a mere #ae1jjj1jjj71 physicists would have to raise their sights to beyond the billion-degree mark4 ,illustration3 ,a supernova photographed on ,march #aj1 #aice4 ,illustration3 ,the same star on ,may #f4 ,this would make it seem almost essential to use hydrogen-#c in one fashion or another4 ,even if it can't be prepared in quantity to begin with1 it might be formed by neutron bombardment of lithium1 with the neutrons being formed by the fusion reaction4 ,in this way1 you would start with lithium and hydrogen-#b plus a little hydrogen-#c4 ,the hydrogen-#c is formed as fast as it is used up4 ,although in the end hydrogen is converted to helium in a controlled fusion reaction as in the sun1 the individual steps in the reaction under human control are quite different from those in the sun4 ,still1 even the temperatures required for hydrogen-#c represent an enormous problem1 particularly since the temperature must not only be reached1 but must be held for a period of time4 7,you can pass a piece of paper rapidly through a candle flame without lighting it4 ,it must be held in the flame for a short period to give it a chance to heat and ignite47 ,the ,english physicist ,john ,david ,lawson 7#aibc- 7 worked out the requirements in #aieg4 ,the time depended on the density of the gas4 ,the denser the gas1 the shorter the period over which the temperature had to be maintained4 ,if the gas is about one hundred-thousand times as dense as air1 the proper temperature must be held1 under the most favorable conditions1 for about one thousandth of a second4 ,there are a number of different ways in which a quantity of hydrogen can be heated to very high temperatures--through electric currents1 through magnetic fields1 through laser beams and so on4 ,as the temperature goes up into the tens of thousands of degrees1 the hydrogen atoms 7or any atoms7 are broken up into free electrons and bare nuclei4 ,such a mixture of charged particles is called a 8plasma04 ,ever since physicists have begun to try to work with very hot gases1 with fusion energy in mind1 they have had to study the properties of such 8plasma01 and a whole new science of 8plasma physics0 has come into existence4 ,but if you do heat a gas to very high temperatures1 it will tend to expand and thin out to uselessness4 ,how can such a super-hot gas be confined in a fixed volume without an enormous gravitational field to hold it together8 ,an obvious answer would be to place it in a container1 but no ordinary container of matter will serve to hold the hot gas4 ,you may think this is because the temperature of the gas will simply melt or vaporize whatever matter encloses it4 ,this is not so4 ,although the gas is at a very high temperature1 it is so thin that it has very little total heat4 ,it does not have enough heat to melt the solid walls of a container4 ,what happens instead is that the hot plasma cools down the moment it touches the solid walls and the entire attempt to heat it is ruined4 ,what's more1 if you try to invest the enormous energies required to keep the plasma hot despite the cooling effect of the container walls1 then the walls will gradually heat and melt4 ,nor must one wait for the walls to melt and the plasma to escape before finding the attempt at fusion ruined4 ,even as the walls heat up they liberate some of their own atoms into the plasma and introduce impurities that will prevent the fusion reaction4 ,any material container is therefore out of the question4 ,fortunately1 there is a nonmaterial way of confining plasma4 ,since plasma consists of a mixture of electrically charged particles1 it can experience electromagnetic interactions4 ,instead of keeping the plasma in a material container1 you can surround it by a magnetic field that is designed to keep it in place4 ,such a magnetic field is not affected by any heat1 however great1 and cannot be a source of material impurity4 ,in #aicd1 the ,american physicist ,willard ,harrison ,bennett 7#aijc- 7 had worked out a theory dealing with the behavior of magnetic fields enclosing plasma4 ,it came to be called the 8pinch effect0 because the magnetic field pinched the gas together and held it in place4 ,the first attempt to make use of the pinch effect for confining plasma1 with eventual ignition of fusion in mind1 was in #aiea by the ,english physicist ,alan ,alfred ,ware 7#aibd- 74 ,other physicists followed1 not only in ,great ,britain1 but in the ,united ,states and the ,soviet ,union as well4 ,the first use of the pinch effect was to confine the plasma in a cylinder4 ,this1 however1 could not be made to work4 ,the situation was too unstable4 ,the plasma was held momentarily1 then writhed and broke up4 ,illustration3 ,plasma in a magnetic field4 ,illustration3 ,enormous machines and complex equipment1 such as the ,scyllac machine shown above1 are required for nuclear fusion research4 ,attempts were made to remove the instability4 ,the field was so designed as to be stronger at the ends of the cylinder than elsewhere4 ,the particles in the plasma would stream toward one end or another and would then bounce back producing a so-called 8magnetic mirror04 ,in #aiea the ,american physicist ,lyman ,spitzer1 ,jr4 7#aiad- 7 had worked out the theoretical benefits to be derived from a container twisted into a figure-eight shape4 ,eventually1 such devices were built and called 8stellarators0 from the ,latin word for 8star01 because it was hoped that it would produce the conditions that would allow the sort of fusion reactions that went on in stars4 ,all through the #aiejs and #aifjs1 physicists have been slowly inching toward their goal1 reaching higher and higher temperatures and holding them for longer and longer periods in denser and denser gases4 ,in #aifi the ,soviet ,union used a device called 8,tokamak-#c0 7a ,russian abbreviation for their phrase for 8electric-magnetic07 to keep a supply of hydrogen-#b1 a millionth as dense as air1 in place while heating it to tens of millions of degrees for a hundredth of a second4 ,a little denser1 a little hotter1 a little longer--and controlled fusion might become possible4#e ,,beyond ,,fusion ,antimatter ,is there anything that lies beyond fusion8 ,when hydrogen undergoes fusion and becomes helium1 only #j4g of the original mass of the hydrogen is converted to energy4 ,is it possible to take a quantity of mass and convert all of it1 every bit1 to energy8 ,surely that would be the ultimate energy source4 ,mass for mass1 that would deliver #adj times as much energy as hydrogen fusion would2 it would be as far beyond hydrogen fusion as hydrogen fusion is beyond uranium fission4 ,and1 as a matter of fact1 total annihilation of matter is conceivable under some circumstances4 ,in #aibh the ,english physicist ,paul ,adrien ,maurice ,dirac 7#aijb- 7 presented a treatment of the electron's properties that made it appear as though there ought also to exist a particle exactly like the electron in every respect except that it would be opposite in charge4 ,it would carry a positive electric charge exactly as large as the electron's negative one4 ,if the electron is a particle1 this suggested positively charged twin would be an 8antiparticle04 7,the prefix comes from a ,greek word meaning 8opposite047 ,illustration3 ,p4 ,a4 ,m4 ,dirac ,illustration3 ,the first picture of the positron 7left7 was taken in a ,wilson cloud chamber4 ,on the right is ,c4 ,d4 ,anderson1 the discoverer of the positron4 ,the proton is not the electron's antiparticle4 ,though a proton carries the necessary positive charge that is exactly as large as the negative charge of the electron1 the proton has a much larger mass than the electron has4 ,dirac's theory required that the antiparticle have the same mass as the particle to which it corresponded4 ,in #aicb ,c4 ,d4 ,anderson was studying the impact of cosmic particles on lead4 ,in the process1 he discovered signs of a particle that left tracks exactly like those of an electron1 but tracks that curved the wrong way in a magnetic field4 ,this was a sure sign that it had an electric charge opposite to that of the electron4 ,he had1 in short1 discovered the electron's antiparticle and this came to be called the 8positron04 ,positrons were soon detected elsewhere too4 ,some radioactive isotopes1 formed in the laboratory by the ,joliot-,curies and by others1 were found to emit positive beta particles--positrons rather than electrons4 ,when an ordinary beta particle1 or electron1 was emitted from a nucleus1 a neutron within the nucleus was converted to a proton4 ,when a positive beta particle1 a positron1 was emitted1 the reverse happened--a proton was converted to a neutron4 ,a positron1 however1 does not endure long after formation4 ,all about it were atoms containing electrons4 ,it could not move for more than a millionth of a second or so before it encountered one of those electrons4 ,when it did1 there was an attraction between the two1 since they were of opposite electric charge4 ,briefly they might circle each other 7to form a combination called 8positronium07 but only very briefly4 ,then they collided and1 since they were opposites1 each cancelled the other4 ,the process whereby an electron and a positron met and cancelled is called 8mutual annihilation04 ,not everything was gone1 though4 ,the mass1 in disappearing1 was converted into the equivalent amount of energy1 which made its appearance in the form of one or more gamma rays4 7,it works the other way1 too4 ,a gamma ray of sufficient energy can be transformed into an electron and a positron4 ,this phenomenon1 called 8pair production01 was observed as early as #aicj but was only properly understood after the discovery of the positron47 ,of course1 the mass of electrons and positrons is very small and the amount of energy released per electron is not enormously high4 ,still1 ,dirac's original theory of antiparticles was not confined to electrons4 ,by his theory1 any particle ought to have some corresponding antiparticle4 ,corresponding to the proton1 for instance1 there ought to be an 8antiproton04 ,this would be just as massive as the proton and would carry a negative charge just as large as the proton's positive charge4 ,an antiproton1 however1 is #ahcf times as massive as a positron4 ,it would take gamma rays or cosmic particles with #ahcf times as much energy to form the proton-antiproton pair as would suffice for the electron-positron pair4 ,cosmic particles of the necessary energies existed but they were rare and the chance of someone being present with a particle detector just as a rare super-energetic cosmic particle happened to form a proton-antiproton pair was very small4 ,illustration3 ,the ,bevatron began operation in #aied4 ,physicists had to wait until they had succeeded in designing particle accelerators that would produce enough energy to allow the creation of proton-antiproton pairs4 ,this came about in the early #aiejs when a device called the 8,cosmotron0 was built at ,brookhaven ,national ,laboratory in ,long ,island in #aieb and another called the 8,bevatron0 at the ,university of ,california in ,berkeley in #aied4 ,using the ,bevatron in #aief1 ,segr 7the discoverer of technetium who had1 by that time1 emigrated to the ,united ,states71 the ,american physicist ,owen ,chamberlain 7#aibj- 71 and others succeeded in detecting the antiproton4 ,the antiproton was as unlikely to last as long as the positron was4 ,it was surrounded by myriads of proton-containing nuclei and in a tiny fraction of a second it would encounter one4 ,the antiproton and the proton also underwent mutual annihilation1 but having #ahcf times the mass1 they produced #ahcf times the energy that was produced in the case of an electron and a positron4 ,there was even an 8antineutron01 a particle reported in #aief by the ,italian-,american physicist ,oreste ,piccioni 7#aiae- 7 and his co-workers4 ,since the neutron has no charge1 the antineutron has no charge either1 and one might wonder how the antineutron would differ from the neutron then4 ,actually1 both have a small magnetic field4 ,in the neutron the magnetic field is pointed in one direction with reference to the neutron's spin2 in the antineutron it is pointed in the other4 ,illustration3 ,bubble chamber photograph of an antiproton annihilation4 ,in #aife the ,american physicist ,leon ,max ,lederman 7#aibb- 7 and his co-workers produced a combination of an antiproton and an antineutron that together formed an 8antideuteron01 which is the nucleus of antihydrogen-#b4 ,this is good enough to demonstrate that if antiparticles existed by themselves without the interfering presence of ordinary particles1 they could form 8antimatter01 which would be precisely identical with ordinary matter in every way except for the fact that electric charges and magnetic fields would be turned around4 ,if antimatter were available to us1 and if we could control the manner in which it united with matter1 we would have a source of energy much greater and1 perhaps1 simpler to produce than would be involved in hydrogen fusion4 ,to be sure1 there is no antimatter on earth1 except for the submicroscopic amounts that are formed by the input of tremendous energies4 ,nor does anyone know of any conceivable way of forming antimatter at less energy than that produced by mutual annihilation1 so that we might say that mankind can never make an energy profit out of it--except that with the memory of ,rutherford's prediction that nuclear energy of any kind could never be tapped1 one hesitates to be pessimistic about anything4 ,the ,unknown ,physical theory makes it seem that particles and antiparticles ought to exist in the universe in equal quantities4 ,yet on earth 7and1 we can be quite certain1 in the rest of the solar system and even1 very likely1 in the rest of the galaxy7 protons1 neutrons1 and electrons are common1 while antiprotons1 antineutrons1 and positrons are exceedingly rare4 ,could it be that when the universe was first formed there were indeed equal quantities of particles and antiparticles but that they were somehow segregated1 perhaps into galaxies and 8antigalaxies08 ,if so1 there might occasionally be collisions of a galaxy and an antigalaxy with the evolution of vast quantities of energy as mutual annihilation on a cosmic scale takes place4 ,there are1 in fact1 places in the heavens where radiation is unusually high in quantity and in energy4 ,can we be witnessing such enormous mutual annihilation8 ,indeed1 it is not altogether inconceivable that we may still have new types of forces and new sources of energy to discover4 ,until about #aijj1 no one suspected the existence of nuclear energy4 ,are we quite sure now that nuclear energy brings us to the end1 and that there is not a form of energy more subtle still1 and greater8 ,in #aifb1 for instance1 certain puzzling objects called 8quasars0 were discovered far out in space1 a billion light-years or more away from us4 ,each one shines from #aj to #ajj times as brilliantly as an entire ordinary galaxy does1 and yet may be no more than a hundred-thousandth as wide as a galaxy4 ,this is something like finding an object #aj miles across that delivers as much total light as #ajj suns4 ,it is very hard to understand where all that energy comes from and why it should be concentrated into so tiny a volume4 ,astronomers have tried to explain it in terms of the four interactions now known1 but is it possible that there is a fifth greater than any of the four8 ,if so1 it is not impossible that eventually man's restless brain may come to understand and even utilize it4 ,,footnotes #a,see ,the ,first ,reactor1 another booklet in this series4 #b,see ,nuclear ,reactors and ,nuclear ,power ,plants1 companion booklets in this series4 #c,see ,breeder ,reactors1 another booklet in this series4 #d,see ,thorium--and the ,third ,fuel1 another booklet in this series4 #e,see ,controlled ,nuclear ,fusion1 another booklet in this series4 ,,quotation ,,credit ,inside front cover ,copyright by ,abelard-,shuman1 ,ltd41 ,new ,york4 ,reprinted by permission from ,inside the ,atom1 ,isaac ,asimov1 #aiff4 ,,reading ,,list ,basic ,books ,basic ,laws of ,matter 7revised edition71 ,harrie ,s4 ,w4 ,massey and ,arthur ,r4 ,quinton1 ,herald ,books1 ,bronxville1 ,new ,york1 #aife1 #agh pp41 #c4ge4 ,grades #g-i4 ,a nontechnical presentation of atoms and the laws governing their behavior4 ,biography of ,physics1 ,george ,gamow1 ,harper ,row1 ,publishers1 ,new ,york1 #aifa1 #cch pp41 #f4ej 7hardback72 #b4ge 7paperback74 ,grades #i-ab4 ,a history of theoretical physics4 ,discoverer of ,x ,rays3 ,wilhelm ,conrad ,roentgen1 ,arnulf ,k4 ,esterer1 ,julian ,messner1 ,new ,york1 #aifh1 #aia pp41 #c4ej4 ,grades #g-aj4 ,this interesting biography includes a brief1 but very helpful1 pronouncing gazetteer of the ,german1 ,swiss1 and ,dutch names in the text4 ,ernest ,rutherford3 ,architect of the ,atom1 ,peter ,kelman and ,a4 ,harris ,stone1 ,prentice-,hall1 ,inc41 ,englewood ,cliffs1 ,new ,jersey1 #aifi1 #gb pp41 #c4ie4 ,grades #e-g4 ,a well-done biography of this famous atomic scientist4 ,many of the drawings illustrate theoretical ideas very well for the elementary grades4 ,a glossary is included4 ,enrico ,fermi3 ,atomic ,pioneer1 ,doris ,faber1 ,prentice-,hall1 ,inc41 ,englewood ,cliffs1 ,new ,jersey1 #aiff1 #hf pp41 #c4ie4 ,grades #e-h4 ,a biography of the man who built the first reactor4 ,giant of the ,atom3 ,ernest ,rutherford1 ,robin ,mc,kown1 ,julian ,messner1 ,new ,york1 #aifb1 #aia pp41 #c4ej4 ,grades #g-ab4 ,the life and accomplishments of a great physicist4 ,the ,history of the ,atomic ,bomb1 ,michael ,blow1 ,american ,heritage ,publishing ,company1 ,inc41 ,new ,york1 #aifh1 #aej pp41 #e4ie4 ,grades #e-i4 ,this sumptuously illustrated history provides an informative explanation of nuclear physics in addition to comprehensive coverage of the bomb's development and use4 ,inside the ,atom1 ,isaac ,asimov1 ,abelard-,schuman1 ,ltd41 ,new ,york1 #aiff1 #aig pp41 #d4jj4 ,grades #g-aj4 ,this comprehensive1 well-written text explains nuclear energy and its applications4 ,madame ,curie3 ,a ,biography1 ,eve ,curie1 translated by ,vincent ,sheean1 ,doubleday and ,company1 ,inc41 ,new ,york1 #aicg1 #che pp41 #e4ie 7hardback72 #j4ie 7paperback74 ,grades #i-ab4 ,this superb biography1 which won the #aicg ,national ,book ,award for ,nonfiction1 illustrates dramatically the full spectrum of ,marie ,curie's life4 ,men ,who ,mastered the ,atom1 ,robert ,silverberg1 ,g4 ,p4 ,putnam's ,sons1 ,new ,york1 #aife1 #aic pp41 #c4di4 ,grades #g-i4 ,atomic energy history is told through the work of pioneer scientists from ,thales to present-day researchers4 ,the ,neutron ,story1 ,donald ,j4 ,hughes1 ,doubleday and ,company1 ,inc41 ,new ,york1 #aiei1 #aeh pp41 out of print4 ,grades #g-i4 ,a substantial and interesting account of neutron physics4 ,niels ,bohr3 ,the ,man ,who ,mapped the ,atom1 ,robert ,silverberg1 ,mac,rae ,smith ,company1 ,philadelphia1 ,pennsylvania1 #aife1 #ahi pp41 #c4ie4 ,grades #h-ab4 ,an exciting1 suspenseful1 and humorous biography of one of the pioneers in atomic energy4 ,includes a glossary and references4 ,the ,questioners3 ,physicists and the ,quantum ,theory1 ,barbara ,lovett ,cline1 ,crowell ,collier and ,mac,millan1 ,inc41 ,new ,york1 #aife1 #bgd pp41 #e4jj 7hardback72 available in paperback with the title ,men ,who ,made ,a ,new ,physics3 ,physicists and the ,quantum ,theory1 ,new ,american ,library1 ,inc41 ,new ,york1 #j4ge4 ,grades #i-ab4 ,an exceptionally well-delineated and personable account of the development of the quantum theory by physicists in the first quarter of this century4 ,the ,restless ,atom1 ,alfred ,romer1 ,doubleday and ,company1 ,inc41 ,new ,york1 #aifj1 #aih pp41 #a4be4 ,grades #i-ab4 ,a stimulating nonmathematical account of the classic early experiments that advanced knowledge about atomic particles4 ,roads to ,discovery1 ,ralph ,e4 ,lapp1 ,harper and ,row1 ,publishers1 ,new ,york1 #aifj1 #aia pp41 out of print4 ,grades #aj-ab4 ,historical survey of nuclear physics beginning with ,roentgen's discovery of ,x rays and concluding with the discoveries of the rare elements4 ,secret of the ,mysterious ,rays3 ,the ,discovery of ,nuclear ,energy1 ,vivian ,grey1 ,basic ,books1 ,inc41 ,publishers1 ,new ,york1 #aiff1 #abj pp41 #c4ie4 ,grades #d-h4 ,this outstanding history of nuclear research from ,roentgen to ,fermi is dramatically presented4 ,the uncertainty of the unknown1 the accidental discovery and the often lengthy and tedious research are woven in this story of scientists from around the world who pooled their knowledge and experience to unlock 8the secrets of the mysterious rays04 ,wilhelm ,roentgen and the ,discovery of ,x ,rays1 ,bern ,dibner1 ,franklin ,watts1 ,inc41 ,new ,york1 #aifh1 #adi pp41 #b4ie4 ,grades #e-h4 ,this detailed biography1 illustrated with line drawings1 historical photographs1 and papers1 is a fine addition to ,watts' 8,immortals of ,science0 ,series4 ,working with ,atoms1 ,otto ,r4 ,frisch1 ,basic ,books1 ,inc41 ,new ,york1 #aife1 #if pp41 #d4ie4 ,grades #i-ab4 ,dr4 ,frisch presents a history of nuclear energy research and provides experiments for the reader4 ,he gives a personal account of the pioneering work in which he and ,lise ,meitner explained the splitting of uranium and introduced the term 8nuclear fission04 ,advanced ,books ,an ,american ,genius3 ,the ,life of ,ernest ,orlando ,lawrence1 ,herbert ,childs1 ,e4 ,p4 ,dutton and ,company1 ,inc41 ,new ,york1 #aifh1 #egf pp41 #ab4ie4 ,this well-written1 scientifically accurate1 and very interesting biography captures the excitement of ,lawrence's life4 ,ernest ,lawrence was the inventor of the cyclotron1 a major member of the wartime atomic energy development1 and the director of the ,lawrence ,radiation ,laboratory4 ,the ,atom and ,its ,nucleus1 ,george ,gamow1 ,prentice-,hall1 ,inc41 ,englewood ,cliffs1 ,new ,jersey1 #aifa1 #aec pp41 #a4be4 ,a popular-level discussion of nuclear structure and the applications of nuclear energy4 ,atomic ,energy for ,military ,purposes1 ,henry ,d4 ,smyth1 ,princeton ,university ,press1 ,princeton1 ,new ,jersey1 #aide1 #cjh pp41 #d4jj4 ,a complete account of the wartime project that developed the first nuclear weapons and of the considerations that prompted their use4 ,atomic ,quest1 ,arthur ,h4 ,compton1 ,oxford ,university ,press1 ,inc41 ,new ,york1 #aief1 #cgj pp41 #g4ie4 ,a personal narrative of the research that led to the release of atomic energy on a useful scale by a scientist who played a principal part in the atomic bomb project during ,world ,war ,,ii4 ,the ,atomists 7#ahje-aicc71 ,basil ,schonland1 ,oxford ,university ,press1 ,inc41 ,new ,york1 #aifh1 #aih pp41 #e4fj4 ,this book1 which can be understood by anyone who has had a high school physics course1 presents atomic theory development from ,dalton through ,bohr4 ,it achieves a good balance between popular treatments and highly technical works without slighting the technical aspects4 ,atoms in the ,family3 ,my ,life with ,enrico ,fermi1 ,laura ,fermi1 ,chicago ,university ,press1 ,chicago1 ,illinois1 #aied1 #bfg pp41 #e4jj 7hardback72 #b4de 7paperback74 ,laura ,fermi writes about her husband1 ,enrico ,fermi1 the physicist who led the group that built the first nuclear reactor4 ,the ,born-,einstein ,letters3 ,the ,correspondence ,between ,albert ,einstein and ,max and ,hedwig ,born from #aiaf to #aiee1 commentaries by ,max ,born1 translated by ,irene ,born1 ,walker and ,company1 #aiga1 #bdj pp41 #h4ej4 ,these interesting letters reveal the scientific and personal lives of these two atomic scientists4 ,einstein3 ,his ,life and ,times1 ,philipp ,frank1 ,alfred ,a4 ,knopf1 ,inc41 ,new ,york1 #aiec1 #bih pp41 #f4ie4 ,a brilliant biography that reveals the richness of ,einstein's life and work and the tremendous impact he made upon physics4 ,enrico ,fermi1 ,physicist1 ,emilio ,segr1 ,chicago ,university ,press1 ,chicago1 ,illinois1 #aigj1 #bhh pp41 #f4ie4 ,this biography tells of ,enrico ,fermi's intellectual history1 achievements1 and his scientific style4 ,the scientific problems faced or solved by ,fermi are explained in layman's terms4 ,emilio ,segr was a friend and scientific collaborator who worked with ,fermi for many years4 ,an ,introduction to ,physical ,science3 ,the ,world of ,atoms 7second edition71 ,john ,j4 ,g4 ,mc,cue1 ,the ,ronald ,press ,company1 ,new ,york1 #aifc1 #gge pp41 #i4ej4 ,this textbook was written for college humanities students4 ,j4 ,j4 ,thomson3 ,discoverer of the ,electron1 ,george ,thomson1 ,doubleday and ,company1 ,inc41 ,new ,york1 #aiff1 #bdj pp41 #a4de4 ,this biography1 written by ,j4 ,j4 ,thomson's son1 describes his research at the famed ,cavendish ,laboratory in ,cambridge1 ,england4 ,john ,dalton and the ,atom1 ,frank ,greenaway1 ,cornell ,university ,press1 ,ithaca1 ,new ,york1 #aiff1 #bef pp41 #g4ej4 ,a biography for the general reader and the high school science student4 ,dalton is famous for his development of chemical combinations based on atomic theory4 ,this provided the basis for modern structural theories of chemistry4 ,john ,dalton and the ,atomic ,theory3 ,the ,biography of a ,natural ,philosopher1 ,elizabeth ,c4 ,patterson1 ,doubleday and ,company1 ,inc41 ,new ,york1 #aigj1 #cbj pp41 #f4ie 7hardback72 #a4ie 7paperback74 ,the drama of ,dalton's life--his rigorous self-teaching1 scientific work1 and struggle to overcome class barriers in #aith century ,england--is well presented4 ,quotations from letters1 diaries1 and published works give a clear picture of ,dalton's atomic theory research and his time4 ,man-made ,transuranium ,elements1 ,glenn ,t4 ,seaborg1 ,prentice ,hall1 ,inc41 ,englewood ,cliffs1 ,new ,jersey1 #aifc1 #abj pp41 #f4ie 7hardback72 #b4ie 7paperback74 ,the discovery1 properties1 and applications of elements heavier than uranium are considered in this book1 which is designed as an introduction to the subject4 ,glenn ,seaborg was co-discoverer of nine of the twelve transuranium elements4 ,the ,nature of ,matter3 ,physical ,theory from ,thales to ,fermi1 ,ginestra ,amaldi1 translated by ,peter ,astbury1 ,chicago ,university ,press1 ,chicago1 ,illinois1 #aiff1 #ccb pp41 #e4ie4 ,a nontechnical history of atomic energy4 ,niels ,bohr3 ,his ,life and ,work as ,seen by ,his ,friends and ,colleagues1 ,s4 ,rozental 7,editor71 ,john ,wiley and ,sons1 ,inc41 ,new ,york1 #aifg1 #cee pp41 #e4ie4 ,an articulate and scholarly biography by the friends and co-workers of this outstanding atomic pioneer4 ,niels ,bohr3 ,the ,man1 ,his ,science1 and the ,world ,they ,changed1 ,ruth ,moore1 ,alfred ,a4 ,knopf1 ,inc41 ,new ,york1 #aiff1 #dcf pp41 #g4ie4 ,an interesting biography of one of the pioneers in the study of the internal structure of the atom4 ,otto ,hahn3 ,my ,life1 ,otto ,hahn1 translated by ,ernest ,kaiser and ,eithne ,wilkins1 ,herder and ,herder1 ,inc41 ,new ,york1 #aigj1 #bdj pp41 #f4ej4 ,autobiography of the man who discovered that the atom could be split4 ,otto ,hahn3 ,a ,scientific ,autobiography1 ,otto ,hahn1 ,willy ,ley1 editor and translator1 ,charles ,scribner's ,sons1 ,new ,york1 #aiff1 #cbj pp41 #i4ie4 ,otto ,hahn1 winner of the #aidd ,nobel ,prize for his work in atomic fission1 reviews the pioneer days in which a new science was created1 and the role he played in its development4 ,physics and ,beyond3 ,encounters and ,conversations1 ,werner ,heisenberg1 translated by ,arthur ,j4 ,pomerans1 ,harper and ,row1 ,publishers1 ,new ,york1 #aigj1 #bdg pp41 #g4ie4 ,werner ,heisenberg1 a ,nobel ,prize physicist1 presents his autobiography in the form of conversations with such men as ,max ,planck1 ,albert ,einstein1 ,niels ,bohr1 ,ernest ,rutherford1 ,otto ,hahn1 and ,enrico ,fermi4 ,physics for ,poets1 ,robert ,h4 ,march1 ,mc,graw-,hill ,book ,company1 ,new4 ,york1 #aigj1 #cjb pp41 #g4ej4 ,a physics textbook for nonscience students4 ,the book covers certain developments of classical mechanics1 relativity1 and atomic and quantum physics4 ,with this book the author won the #aiga ,american ,institute of ,physics--,u4 ,s4 ,steel ,foundation ,science ,writing ,award in ,physics and ,astronomy4 ,sourcebook on ,atomic ,energy 7third edition71 ,samuel ,glasstone1 ,van ,nostrand ,reinhold ,company1 ,new ,york1 #aifg1 #hhc pp41 #ae4jj4 ,an excellent standard reference work1 written for both scientists and the general public4 ,the ,swift ,years3 ,the ,robert ,oppenheimer ,story1 ,peter ,michelmore1 ,dodd1 ,mead and ,company1 ,new ,york1 #aifi1 #bgc pp41 #f4ie4 ,oppenheimer's complex personality is delineated in this well-written biography4 ,in the bibliography is a list of books that ,oppenheimer felt 8had done the most to shape his vocational attitude and philosophy of life04 ,the ,world of the ,atom1 #b volumes1 ,henry ,a4 ,boorse and ,lloyd ,motz 7,eds471 ,basic ,books1 ,inc41 ,publishers1 ,new ,york1 #aiff1 #ahgc pp41 #ce4jj4 ,contains the actual text of landmark documents in the history of atomic physics1 each preceded by commentary that places it in the context of the discoverer's personal life and in the conditions prevailing in science and in society in his time4 ,photo ,credits ,page facing inside ,the 8,horsehead0 ,nebula in ,orion4 ,hale cover ,observatories4 ,author's ,photo ,jay ,k4 ,klein ,contents page ,lick ,observatory #aaf ,samuel ,a4 ,goudsmit #aah ,from ,atoms in the ,family3 ,my ,life ,with ,enrico ,fermi1 ,laura ,fermi1 #aied4 ,copyright by the ,university of ,chicago ,press4 #abj ,top row1 left1 ,institut fur ,radium-forschung und ,kemphysik1 right1 ,lotte ,meitner-,graff1 middle row1 left1 ,nobel ,institute1 right1 ,ernest ,orlando ,lawrence ,berkeley ,laboratory2 bottom row1 right1 ,ernest ,orlando ,lawrence ,berkeley ,laboratory1 left1 ,p4 ,h4 ,abelson4 #abc ,addison-,wesley ,publishing ,company #acj ,top1 ,ike ,verne2 bottom1 ,oak ,ridge ,national ,laboratory4 #acb #acc ,letter and ,roosevelt picture from the ,franklin ,d4 ,roosevelt ,library2 ,johan ,hagemeyer4 #acf #acg ,argonne ,national ,laboratory #ada ,u4 ,s4 ,navy #adc ,right1 ,westinghouse ,electric ,corporation #ade ,argonne ,national ,laboratory #aeb ,lick ,observatory #aee ,gulf ,energy and ,environmental ,systems #aef ,los ,alamos ,scientific ,laboratory #aeh ,nobel ,institute #aei ,left1 ,c4 ,d4 ,anderson2 right1 ,nobel ,institute4 #afa ,ernest ,orlando ,lawrence ,berkeley ,laboratory ,u4 ,s4 ,,government ,,printing ,,office3 #aigb - #gdg-ahi_/b ,the ,u4 ,s4 ,atomic ,energy ,commission publishes this series of information booklets for the general public4 ,these booklets explain the many uses of nuclear energy4 ,the booklets are listed below by subject category4 ,general ,interest ,,was-#jji ,atomic ,energy and ,your ,world ,,was-#jjb ,a ,bibliography of ,basic ,books on ,atomic ,energy ,,was-#jjd ,computers ,,was-#jjh ,electricity and ,man ,,was-#jjf ,nuclear ,terms1 ,a ,glossary ,,was-#jac ,secrets of the ,past3 ,nuclear ,energy ,applications in ,art and ,archaeology ,the ,environment ,,was-#dad ,nature's ,invisible ,rays ,,was-#bjd ,nuclear ,power and the ,environment ,biology ,,was-#ajb ,atoms in ,agriculture ,,was-#aje ,the ,genetic ,effects of ,radiation ,,was-#ajg ,radioisotopes in ,medicine ,,was-#aji ,your ,body and ,radiation ,physics ,,was-#dja ,accelerators ,,was-#djc ,controlled ,nuclear ,fusion ,,was-#djd ,direct ,conversion of ,energy ,,was-#daf ,inner ,space3 ,the ,structure of the ,atom ,,was-#djf ,lasers ,,was-#djg ,microstructure of ,matter ,,was-#daa ,power from ,radioisotopes ,chemistry ,,was-#cjc ,the ,atomic ,fingerprint3 ,neutron ,activation ,analysis ,,was-#cjb ,cryogenics1 ,the ,uncommon ,cold ,,was-#cjf ,radioisotopes in ,industry ,nuclear ,reactors ,,was-#ejb ,atomic ,power ,safety ,,was-#eac ,breeder ,reactors ,,was-#ejc ,the ,first ,reactor ,,was-#eje ,nuclear ,power ,plants ,,was-#ejg ,nuclear ,reactors ,,was-#ejh ,radioactive ,wastes ,members of the general public may obtain free1 single copies of six titles of their choice4 ,librarians and teachers may obtain free a complete set of the booklets4 ,these requests should be made on school or library stationery4 ,those wishing to obtain larger quantities may purchase them if stocks are available4 ,orders for booklets and inquiries on prices and availability should be directed to3 ,,usaec--,technical ,information ,center1 ,p4 ,o4 ,box #fb1 ,oak ,ridge1 ,,tn #cghcj ,comments are invited regarding this booklet and others in the series4 ,illustration3 ,,united ,,states ,,of ,,america ,,atomic ,,energy ,,commission ,u4 ,s4 ,,atomic ,,energy ,,commission ,office of ,information ,services ,transcriber's ,notes --,retained publication information from the printed edition3 this e,book is public-domain in the country of publication4 --,some captions describing separately placed images were split1 removing redundant relative clauses like 8,above0 or 8,to the right is4440 --,in the text version only1 underlined or italicized text is delimited by underscores4 --,where possible1 ,,utf superscript and subscript numbers are used2 some e-reader fonts may not support these characters4 --,in the text versions only1 other superscript text is preceded by caret and delimited by brackets4 --,in the text versions only1 other subscripted text is preceded by underscore and delimited by brackets4 --,the ,table of ,contents lists pages and illustrations in all three volumes3 --,volume #a --,volume #b --,volume #c --,these links can be made to function on local copies of the files4