,transcriber's ,notes3 ,underscores 80 before and after a word or phrase indicate italics in the original text4 ,equal signs 80 before and after a word or phrase indicate bold in the original text4 ,illustrations have been moved so they do not break up paragraphs4 ,typographical and punctuation errors have been silently corrected4 ,army ,pulse ,radiation ,facility ,illustration ,contents ,page ,no4 ,the ,concept #c ,the ,facility #e ,the ,reactor #g ,exposure ,locations and ,performance ,levels #aa ,,aprf ,user ,support ,facilities #ag ,instructions to ,potential ,users #bj ,table ,i4 ,,aprfr ,core ,design ,data #h ,table ,,ii4 ,typical ,,aprfr ,performance ,levels #h ,table ,,iii4 ,,aprfr ,fluence and ,flux ,data #ac ,table ,,iv4 ,nominal ,,aprfr ,leakage and ,u#bce ,fission ,spectra #ac ,table ,v4 ,fluence-to-,dose ,conversion ,factors for ,,aprfr ,leakage ,neutrons #ad ,table ,,vi4 ,kerma and ,kerma ,rate in ,tissue for ,,aprfr ,exposure ,conditions #ad ,table ,,vii4 ,kerma and ,kerma ,rate in ,silicon for ,,aprfr ,exposure ,conditions #ae ,table ,,viii4 ,neutron-to-,gamma ,dose ,ratios #ae ,table ,,ix4 ,,aprf ,user ,support ,equipment #ah ,army ,pulse ,radiation ,facility ,u4,s4 ,army ,ballistic ,research ,laboratories ,,amxrd-,,btd ,aberdeen ,proving ,ground1 ,maryland #bajje ,illustration3 ,army ,pulse ,radiation ,facility ,location ,map ,illustration ,the ,concept ,the ,army ,pulse ,radiation ,facility 7,,aprf7 is designed to meet an ,army need for a facility located near the ,eastern ,seaboard capable of providing large fast neutron and gamma radiation doses within microseconds4 ,this fast pulse radiation capability is necessary for the determination of transient responses of materiel in nuclear environments4 ,the ,,aprf increases ,army capability by providing improved simulation of radiative effects of a nuclear burst for studies of ,army interest1 and provides a facility for testing ,army materiel4 ,because of its location1 the ,,aprf economically and efficiently serves the heavy concentration of ,army agencies and contractors located along the ,eastern ,seaboard4 ,the design of the ,,aprf is a direct outgrowth of projected user requirements4 ,thus the reactor can be used both for high dose irradiations of small objects1 as a point source for radiation detector studies1 and irradiation of bulk objects4 ,the former requirement led to the incorporation of a #a-;inch ,,od 8glory hole0 running through the center of the core1 and providing a fast neutron fluence of about #i #aj neutrons per square centimeter per pulse4 ,the latter two requirements have resulted in the design of a large volume1 low-radiation backscatter ,reactor ,building4 ,provision is made for moving the reactor both within the ,reactor ,building and to an outdoor test site at heights variable up to #dd feet above ground by means of a mechanical device called the reactor transporter4 ,the reactor is also capable of intermittent steady state operation in the kilowatt range for classes of experiments requiring this mode of operation4 ,illustration ,illustration ,illustration ,the ,facility ,the ,,aprf is located on the military reservation of ,aberdeen ,proving ,ground 7,,apg71 in southeastern ,harford ,county1 ,maryland4 ,the ,reactor ,building is at the center of the facility4 ,this building is a windowless1 circular structure with aluminum siding4 ,inside1 the building is #ajj feet in diameter and #fe feet high4 ,there is a roll-up door in the south wall for the passage of the reactor transporter to the outdoor test site and another in the west wall for the access of vehicles to the building4 ,a shielded stairway and maze provides access from the underground ,control ,building4 ,this concrete structure provides radiological shielding for the personnel and controls associated with the operation of the reactor and the conduct of experiments4 ,the area within a #dej-yard radius of the ,reactor ,building constitutes the ,,aprf high-radiation area defined by a #aj-;foot anti-personnel fence4 ,this high-radiation area is in turn surrounded by a nearly concentric restricted area defined at its outer boundary by a barbed wire warning fence at a radius of #aejj yards from the ,reactor ,building4 ,the ,laboratory ,building1 located at the periphery of the restricted area1 houses the administrative and support personnel for the ,,aprf4 ,access to ,,aprf is controlled at this point4 ,illustration3 ,,aprf ,reactor ,core ,assembly ,illustration ,the ,reactor ,the reactor1 7,,aprfr71 is designed for both self-limited1 super-prompt-critical pulse operation and steady state operation4 ,the maximum available pulse has a yield of #b4a #aj fissions1 while steady state operation is limited to about #aj kilowatts by the reactor core cooling system and activation of the core4 ,illustration3 ,high ,yield ,prompt ,pulse ,shape ,the ,,aprfr is an advanced version of the ,health ,physics ,research ,reactor 7,,hprr7 at ,oak ,ridge ,national ,laboratory 7,,ornl71 which has been operating since #aifb4 ,,ornl has played a key role in the design and testing of the ,,aprfr4 ,in pulse operation1 the power level may rise on periods as short as #aj microseconds4 ,electro-mechanical scram systems are too slow to terminate such an excursion4 ,shutdown results from increased neutron leakage due to fuel expansion1 resulting in a large prompt negative temperature coefficient of reactivity4 ,this self-limiting feature depends almost entirely on the thermal expansion of the fuel alloy1 and thus it is regarded as completely reliable and safe4 ,following a pulse1 additional reactor shutdown capability is provided by a safety block which1 when ejected from the core1 reduces the reactivity to about #bj dollars below delayed-critical4 ,at lower yield pulses1 below about #f #aj fissions1 the safety block is ejected by the electro-mechanical scram system in about #j4a seconds after a pulse4 ,at higher yield pulses1 the safety block is ejected in much shorter times due to thermo-mechanical shock forces which cause the safety block to bounce out4 ,the large shutdown margin provided by the safety block is also the primary design device for preventing accidental criticalities during periods of reactor shutdown4 ,the ,,aprfr core is an unmoderated cylindrical assembly containing about #abe kilograms of an alloy of uranium #bce containing #aj molybdenum4 ,the actual core mass varies with the experiment4 ,the core is cylindrical and consists of two concentric annuli3 a fixed outer shell of stacked fuel discs bolted together with nine fuel bolts and ,inconel nuts and a movable inner safety block1 also of fuel alloy4 ,the #a-;inch ,,od 8glory hole0 runs vertically through the center of the safety block4 ,key reactor data is summarized in ,tables ,i and ,,ii4 ,the ,,aprfr has been operated during tests at ,,ornl at more than twice its design yield4 ,table ,i4 ,,aprfr ,core ,design ,data ,core ,diameter #h4ij inches ,core ,height#a #h4j inches ,fuel ,alloy #ij wt uranium - #aj wt molybdenum ,uranium-#bce ,enrichment #ic4ad ,total ,fuel ,mass#b #abe ,safety ,block ,mass #ae4g kg ,safety ,block ,height #h4jf inches ,safety ,block ,diameter #d4jj inches ,glory ,hole ,diameter #a4ej inches ,number of ,control ,rods ,three ,core ,cooling ,forced ,air ,number of ,core ,bolts ,nine ,safety ,block ,reactivity ,worth #bj ,pulse ,rod ,reactivity ,worth #a4ae ,core ,environment ,during ,pulse ,dry ,nitrogen ,core ,cooling ,forced ,air #a ,this value varies with experimental environment of core4 #b ,this value varies with experimental environment of core4 ,table ,,ii4 ,typical ,,aprfr ,performance ,levels ,,pulse ,,mode ,routine ,yield #a4e #aj fissions_/pulse ,reactivity ,insertion #a4aj ,pulse ,half-,width #dh sec ,initial ,prompt ,period #ah sec ,maximum ,fuel ,temperature ,rise #djj;,c ,temperature ,coefficient -#j4c cents_/,c ,maximum ,available ,yield #b4a #aj fissions_/pulse ,,steady ,,state ,,mode ,continuous ,operation #a kw ,intermittent ,operation #aj kw ,steady state power levels are limited by effectiveness of core cooling system and core activation4 ,illustration ,illustration3 ,,aprf ,floor ,plan ,exposure ,locations and ,performance ,levels ,the highest fluence and dose rates are available in the #a-;inch glory hole4 ,since the reactor is supported from above by the transporter1 the areas around and below the core are also available for experiments4 ,the core can be positioned by remote control anywhere within the range of travel of the transporter4 ,vertical travel is limited to about #dd feet above the ,reactor ,building floor level4 ,horizontal travel is limited by the range of the rails on which the transporter travels4 ,six pairs of rails extend radially from a turntable in the center of the ,reactor ,building4 ,these rails terminate within the ,reactor ,building1 except for one pair which extends #ij feet outside the building to an outdoor test site4 ,each pair of rails defines one experimental location where semi-permanent equipment and shielding can be set up without tying up the entire reactor operation4 ,fluence and flux data for three typical exposure locations are given in ,table ,,iii4 ,in the absence of reflecting material beyond #a meter from core center 7position ,p#c71 these values fall off essentially as #a ---- ,r where ,r is the distance to core center4 ,other performance data are summarized in ,tables ,,iv through ,,viii4 ,illustration ,illustration ,illustration ,illustration ,table ,,iii4 ,,aprfr ,fluence and ,flux ,data ---------------------------------------- --------------------------- ,routine ,pulse ,yield ,maximum ,pulse ,yield #a4e #aj ,fissions #b4a #aj ,fissions ---------------------------------------- --------------------------- ,fluence1 n_/cm ,p#ac #f4g #aj #i4c #aj ,p#b #b4j #aj #b4h #aj ,p#c #a4g #aj #b4d #aj ,flux ,density1 n_/cm_/sec ,p#a #a4d #aj #b4j #aj ,p#b #d4c #aj #f4j #aj ,p#c #c4g #aj #e4b #aj #c ,p#a3 ,center of ,glory ,hole2 ,p#b3 ,core ,surface 7#aa4c cm from ,core ,center72 ,p#c3 #a meter from ,core ,center4 ,table ,,iv4 ,nominal ,,aprfr ,leakage and ,u#bce ,fission ,spectra#d ---------------------------------------- ---------------- ,energy ,average ,,aprfr ,u#bce ,fission ,group ,energy ,energy ,spectrum ,spectrum ,number ,range ,e ,fraction ,fraction n 7,mev7 7,mev7 ,x,e ,x,e ---------------------------------------- ---------------- #a #c4j- #d4da #j4acc #j4bjd #b #a4d-c4j #b4aj #j4bea #j4cdd #c #j4i-a4d #a4ad #j4afd #j4afh #d #j4d-j4i #j4fe #j4bfb #j4ahj #e #j4a-j4d #j4bf #j4afh #j4jij #f #j-j4a #j4jei #j4jbb #j4jad ------------------- ,,sum #a4jjj #a4jjj ------------------- ,mean ,energy 7,mev7 #a4ee #a4h #d ,these values are approximate and meant for qualitative comparison only4 ,table ,v4 ,fluence-to-,dose ,conversion ,factors for ,,aprfr ,leakage ,neutrons ---------------------------------------- ---------------------------- ,material ,quantity ,conversion ,factor ---------------------------------------- ---------------------------- ,tissue ,kerma #b4d #aj erg_/gram ----------- neutron_/cm ,tissue ,maximum ,absorbed ,dose ,for #c4e #aj rad ----------- neutron_/cm ,normally ,incident ,neutrons ,silicon ,elastic ,recoil ,kerma #b4g #aj erg_/gram 7,permanent ,effect7 ----------- neutron_/cm ,silicon ,ionization ,kerma #b4i #aj erg_/gram 7,transient ,effects7 ----------- neutron_/cm ,silicon 7,total7 ,kerma #e4f #aj erg_/gram ----------- neutron_/cm ---------------------------------------- ---------------------------- ,table ,,vi4 ,kerma and ,kerma ,rate in ,tissue for ,,aprfr ,exposure ,conditions ---------------------------------------- ---------------------------- ,routine ,pulse ,yield ,maximum ,pulse ,yield #a4e #aj ,fissions #b4a #aj ,fissions ---------------------------------------- ---------------------------- ,kerma in ,tissue 7ergs_/gm7 ,p#ae #a4f #aj #b4b #aj ,p#b #d4i #aj #f4h #aj ,p#c #d4a #aj #e4g #aj ,kerma ,rate in ,tissue 7ergs_/gm_/sec7 ,p#a #c4e #aj #d4g #aj ,p#b #a4a #aj #a4e #aj ,p#c #h4h #aj #a4b #aj #e ,p#a3 ,center of ,glory ,hole2 ,p#b3 ,core ,surface2 ,p#c3 #a ,meter from ,core ,center4 ,illustration ,illustration ,illustration ,illustration ,table ,,vii4 ,kerma and ,kerma ,rate in ,silicon for ,,aprfr ,exposure ,conditions ---------------------------------------- ---------------------------- ,routine ,pulse ,yield ,maximum ,pulse ,yield #a4e #aj ,fissions #b4a #aj ,fissions ---------------------------------------- ---------------------------- ,total ,kerma in ,silicon1 ergs_/gm#f ,p#ag #b4g #aj #e4b #aj ,p#b #a4a #aj #a4f #aj ,p#c #i4e #aj #ac4c #aj ,total ,kerma ,rate in ,silicon1 7ergs_/gm_/sec7 ,p#a #e4h #aj #aa4j #aj ,p#b #b4d #aj #c4e #aj ,p#c #b4j #aj #b4i #aj #f ,ionization and elastic recoil processes contribute roughly equal amounts to the total kerma4 #g ,p#a3 ,center of ,glory ,hole2 ,p#b3 ,core ,surface2 ,p#c3 #a ,meter from ,core ,center4 ,table ,,viii4 ,neutron-to-,gamma ,dose ,ratios#h ---------------------------------------- ------------------------- neutron rads tissue n_/cm_/sec ------------------- ----------------- gamma rads tissue gamma rads tissue ---------------------------------------- ------------------------- ,core ,center 7,p#a7 #aj #b4g #aj ,core ,surface 7,p#b7 #aj #b4g #aj #a ,meter from ,core ,center 7,p#c7 #i #c4c #aj #aj ,meters from ,core ,center #g #b4e #aj #h ,representative data4 ,actual values influenced by core operating history4 ,illustration3 ,cross ,section of ,reactor ,building ,,aprf ,user ,support ,facilities ,,aprf is designed and staffed to assist its users in all key areas relating to reactor utilization4 ,physical ,space ,several areas in the underground ,control ,building are available to experimenters4 ,these include the trailer tunnel with room for two full-sized trailers1 the data acquisition room1 and the instrument shop4 ,all of these areas are provided with conduits so that cables can be run directly to them from the ,reactor ,building4 ,in the trailer tunnel the minimum cable length required to run to the core surface is about #cj feet4 ,the exposure areas in the ,reactor ,building and the outdoor test site are equipped with conduits for communication and instrumentation cables4 ,available areas in the ,laboratory ,building include a high-bay set up area1 a machine shop1 laboratory space1 fume hood with remote manipulator1 photography laboratory1 and offices4 ,data ,acquisition and ,processing ,the basic element here is the ,,aprf ,data ,acquisition ,system described in ,table ,,ix4 ,various other instrumentation is available as summarized in ,table ,,ix4 ,data processing is available at the ,,ardc computer center and with on-line equipment at ,,aprf4 ,dosimetry ,routine dosimetry is performed by ,,aprf personnel4 ,methods available include fluence and spectrum measurements using foil techniques1 glass rod microdosimetry1 thermoluminescence1 and diverse active dosimeters4 ,foils are analyzed using the ,,aprf ,automatic ,dosimetry ,system and data are available within a short time following exposure4 ,measurements are supplemented by analytical methods including one and two dimensional transport theory1 ,monte ,carlo1 and special foil analysis codes4 ,staff ,the ,,aprf staff is available to guide1 plan and set up experiments at the reactor1 perform dosimetry1 and assist in data acquisition4 ,,aprf participation is determined on a case-by-case basis4 ,health ,physics ,health physics survey1 monitoring1 decontamination and related services are available in conjunction with the ,,brl ,health ,physics ,division4 ,table ,,ix4 ,,aprf ,user ,support ,equipment ---------------------------------------- ---------------------------- ,transient ,data ,recording ,system ---------------------------------------- ---------------------------- ,,tape ,,recorders3 ,three each--#ad track ,honeywell ,model #gfjj ,,frequency3 ,,dc to #hj k,hz ,,fm1 #djj ,hz to #gjj k,hz ,direct ,,signal ,universal ,strain gauge and thermocouple with ,,conditioning3 #ajj ,,kc ,,dc amplifiers ,,time ,,code3 ,,irig ,a1 #a millisecond resolution ,,patch ,,panels3 ,coaxial and triaxial connectors for all inputs and outputs1 insulated shields4 ,,auto ,,calibration3 #ej channel1 #c step ,,channel ,,id3 ,automatic ,,id in binary code ,,playback3 #ab0 oscillograph ---------------------------------------- ---------------------------- ,dosimetry ---------------------------------------- ---------------------------- ,basic ,foil ,calibration ,system #ejjj ,curie ,co-#fj source ,automated ,sulfur1 ,fission ,foil and ,gamma ,well ,counting ,system1 #ajj ,samples each per cycle ,eight channel active dosimeter system with digital read out and computer analysis of neutron fluence and energy ,toshiba ,glass ,rod and ,harshaw ,,tld ,gamma ,system ---------------------------------------- ---------------------------- ,computer ---------------------------------------- ---------------------------- #af bit_/#af,k memory with foreground_/background operation4 ,automatic acquisition and reduction of foil counting data on-line4 ,on-line monitoring of reactor power pulse with analysis of peak1 half-width and yield4 ,on-line monitoring of active dosimeters with data reduction4 ,real time_/,fortran ,,iv4 ---------------------------------------- ---------------------------- ,general ,equipment ---------------------------------------- ---------------------------- #ccjj ,nuclear ,data ,multiparameter ,analyzer1 #djif channel with magnetic tape2 ,,ridl #djj ,channel ,pulse ,height ,analyzer4 ,oscilloscopes1 cameras1 electronic calibration equipment4 ,hood areas with manipulators1 photographic laboratory1 radiation monitoring equipment and services1 machine shop4 ---------------------------------------- ---------------------------- ,illustration ,illustration ,illustration ,illustration ,illustration ,instructions ,to ,potential ,users ,it is imperative to realize that there are stringent safety requirements connected with the use of the ,,aprfr4 ,all experiments will follow a written test plan approved at ,,aprf4 ,in order to perform an experiment with maximum usefulness and efficiency1 it is essential that ,,aprf be contacted during the early planning stages of a potential experiment4 ,failure to do this may result in erroneous experiment planning as regards safety and use of exposure space resulting in schedule delays1 and possibly cancellation or drastic revision of the experiment4 ,for further information contact3 ,commanding ,officer ,u4,s4 ,army ,ballistic ,research ,laboratories ,,attn3 ,,amxrd-,,btd1 ,facility ,coordinator ,aberdeen ,proving ,ground1 ,maryland #bajje