,! DECAY ,BP ;Z_< A B1UTY MESON VANI%+ 9TO TWO MUONS IS ! R>E/ "PICLE DECAY "E OBS]V$3 X HAPP5S R\ SE>*1 PRODUC$ ! F/ CR$IBLE SIGNAL F A SCALE N[ CALL$ ! ZEPTOV]SE1 & MATT]S F> 2Y XS R>;Y 2C A DECAY ? UNLIKELY IS ! ,/&>D ,MODEL'S SMALLE/1 CL1NE/ L1K1 & PRECISELY ! SORT ( PLACE UNDISCOV]$ PHYSICS C L1K "?4 ,:AT ! DECAY IS ,! ,BP MESON IS A TWO-QU>K "PICLE A B1UTY " QU>K B.D TO A D[N ANTIQU>K4 ,B1UTY "PICLES RA9 \ ( ,,LHC COLLI.NS BY ! BILLIONS B LIVE ONLY @9#A4E TRILLION?S ( A SECOND 2F DECAY+ ALM ALW 9TO ORD9>Y _HRONIC DEBRIS4 ,9 ,BP 1 "S?+ TOTAL HAPP5S3 ! B1UTY QU>K & ! ANTIQU>K ANNIHILATE EA* O!R COMPLETELY1 & ! 5TIRE "PICLE 3V]TS 9TO A MUONANTIMUON PAIR H1VI] C\S9S ( ! ELECTRON L1V+ ! CL1NE/ POSSIBLE SIGNATURE3 TWO MUONS RECOIL+ F A S+LE PO9T4 ,9 ! ,/&>D ,MODEL ? C'T HAPP5 DIRECTLY "! IS NO TREE-LEVEL R\TE4 ,! DECAY M/ PROCE$ "? QUANTUM LOOP DIAGRAMS1 ) ! B1UTY QU>K BRIEFLY 4SOLV+ 9TO VIRTUAL TOP QU>KS & ;,W BOSONS 2F RE-MAT]IALIZ+ Z MUONS4 ,E /EP ( T *A9 IS SUPPRESS$1 : IS :Y ! PR$ICT$ RATE IS S T9Y & :Y ! PR$IC;N IS S PRECISE4 ,A DECAY ? R>E IS MAXIMALLY S5SITIVE TO ! UNEXPECT$3 ANY NEW "PICLE CAPABLE ( JO9+ ! LOOP A SECOND ,HI7S D\BLET1 A D>K-SECTOR PORTAL1 A ,Z#B BOSON CR1TES A %ORTCUT T M1SURABLY %IFTS ! RATE4 ,PHYSICI/S CALL ? CLASS ( PROCESSES GOLD5 *ANNELS3 R>E 5 T NO?+ ELSE LOOKS L !M1 CL1N 5 T !ORY C SEE A DEVIA;N4 ,! #DB-YE> HUNT "9 #AIHD ,CORNELL'S ,,CLEO EXP]I;T 2G9S ! SE>* = FLAVOR-*ANG+ NEUTRAL-CURR5T B1UTY DECAYS2 ! ]A ( HUNT+ 8"O 9 A BILLION0 OP5S "9 #AIIJ;S#BJJJ;S ,BELLE "<,,KEK1 ,JAPAN"> & ,BA,B> "<,,SLAC1 ,CALI=NIA"> RUN D$ICAT$ ;,B-FACTORIES2 UPP] LIMITS TIN+ BACKGR.D REJEC;N "9 #C ,NOVEMB] #BJBF COMB9+ #BJBD#BJBE DATA ) ! #BJAA#BJAH >*IVE1 ,L,H,CB REPORTS EVID;E AT #C4B SIGMA AB A #J4C.0 *.E ( A FLUKE F A S+LE EXP]I;T = ! F/ "T4 ,! ANALYSIS 0 L$ BY A ,CAMBRIDGE T1M "U ,DR4 ,H>RY ,CLIFF & CO-L$ BY ,,9FN'S ,M>CO ,SANTIM>IA ,:Y "O DECAY OP5S A NEW _W ,! M1SURE;T'S P[] ISN'T J CAT*+ A R>E EV5T X'S SURVEY+ A NEW FRONTI]4 ,R>E DECAYS >E S5SITIVE TO "PICLES F> H1VI] ?AN ANY COLLID] C MAKE DIRECTLY1 2C VIRTUAL "PICLES DON'T OBEY 5]GY 3S]VA;N 9 ! ORD9>Y S5SE !Y C BORR[ MASS F ! QUANTUM FOAM = ! 9/ANT ( ! DECAY4 ,PHYSICI/S E/IMATE T ,BP PROBES PHYSICS AT 4T.ES APPROA*+ #AJ_< METRES ! ZEPTOV]SE MAK+ X A TELESCOPE AIM$ AT T]RITORY NO MICROSCOPE W "E IMAGE4 ,IF ! M1SUR$ RATE "E L&S AWAY F ! ,/&>D ,MODEL'S PR$IC;N1 "S?+ NEW IS HID+ 9 ! LOOP & C&IDATES >E EXACTLY :AT COSMOLOGY IS MISS+3 D>K-MATT] "PICLES1 ! AG5TS ( ! MATT]ANTIMATT] ASYMMETRY "1 H1VI] ,HI7S-L /ATES4 ,= N[ ! M1SUR$ VALUE IS 3SI/5T ) ! ,/&>D ,MODEL : TI.D NEW PHYSICS R ?AN OP5+ ! DOOR1 B ! DOOR IS N[ ON XS H+ES3 ) ,HI<-,LUM9OS;Y ,,LHC DATA1 ! SAME M1SURE;T %>P5S UNTIL EI ! ,/&>D ,MODEL IS 3FIRM$ TO UNN]V+ PRECI.N1 OR "S?+ %[S XS H&4 ,AN H"O/ CAV1T ,! RESULT IS EVID;E AT #C4B SIGMA1 N 4COV]Y ! #E-SIGMA /&>D IS DELIB]ATELY H>D 2C "PICLE PHYSICS HAS BE5 BURN$ 2F "4 ,! M1SURE;T HAS N YET COMPLET$ PE] REVIEW4 ,& ! RATE1 S F>1 AGREES ) !ORY NO NEW "PICLES CAU - ,UNIV]S;Y ( ,CAMBRIDGE 8,PHYSICI/S KNOCK AT ! DOOR ( ! ZEPTOV]SE0 "<#C ,NOV #BJBF"> - ,,9FN-,,LNF 8,L,H,CB ID5TIFIES A DECAY T O3URS ONCE 9 T5 BILLION0 "<,NOV #BJBF"> - ,,CMS @& ,L,H,CB OBS]VA;N ( ;,B 1 ,NATURE #EBB "<#BJAE"> - ,AAIJ ET ;AL4 "<,L,H,CB"> R>E-DECAY PROGRAM PUBLICA;NS