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Martha Washington
5 years ago
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1 SUSY and beyond Stau Physics and Neutralino Dark atter Probing Suersymmetry at at Linear Colliders R. Arnowitt, ) B. Dutta, ) T. amon, ) V. hotilovich )* ) Deartment of Physics, Texas A& University ) Deartment of Physics, Regina University, Canada * Graduate Student /&6D&RUQHOO-O\

2 Talk Outline SUSY and Cosmology A v a i l a b l e m S U G R A arameter sace with (a) Rare decay constraints (b) Collider bounds (c) Cosmological constraints LC ( s= 5 and 8 GeV) reach of the msugra arameter sace via and (i) (ii) Detailed study of signal and the background rocesses Determination of SUSY masses in the dark matter allowed regions (in rogress) Conclusion 785HLQD/&RQH&DUOR6G\

3 Suergravity (SUGRA). Suergravity models with R arity invariance gives rise to a stable dark matter candidate The lightest Neutralino. This neutralino can give rise to the right amount of cold dark matter of the universe. 3. The relic density of these neutralinos is given by x f ³ h dx( V annv!) 4. V ann is calculated in terms of SUSY model arameters. 785HLQD/&RQH&DUOR6G\

4 D A = GH D A = E B f = f N G f f r = D V T ` P C Q ) " O N Q Suergravity (Cont d) >? < = 9; L < D = < = > < = I B P N O D χ χ ZY [ DD@ B O N V A UC E T P RS Q h, H, A, Z + m ^_ R]\ L jlk i fhg Rcbed a Y DD@ B χ P ^_ R]\ Q χ ^_ R%\ q j k i fo R b d i n g R b d ZYu[ DD@ B O N V A UC N T sts "! > = = T% { = C y x \ w z y x _ w v P ' & % = [ TD *,+ = C } A ƒ_ a C = N DB N O O U N O D P - +. / r,ˆ x _ x \ "! % HLQD/&RQH&DUOR6G\

5 N S RL RI P NHI H ` H ` H PP Y z H Hy SZ HL 3 b b b S HL * h ^m ƒ Š u d z Š d D & * Hy } y U T m u Ÿ u NI N h xe V b ž y U T ^ Ÿ Technical Issues and Exerimental Constraints S L I P Q ON HL HI G E Y SZ R L V Q Q UT ach _ g ]^ f [ed acb _ ]^ ^ [\ Y SZ R L Ui T "! l jk go ^ wn _vu U ql jk Ti ts rq go ^ mn,.- *+ ) " (' & % RL R N T Y S R L { S HL PQ SZ R I Ux T V N } N ` b L NHI R R HI G E / / HN { P N ` N R Y z N ON Y N H Ry N HI G L QH 9 " - 8 " - U Z QH, - ; H S I " - g u ƒ g g u ˆ * < =@? < / => ' P Z HS I Vx } Z HL QH ' + - ' 8 u Œm ^gu ƒ ƒ _ Œg g u, A ˆ HI G H ^m E Y S R R L UŽ T - C B Z HL U ON Y N S R IG Y L N E m b Z ON Y N o š TŽ U b P h ON H T^^ Œ ž g ^ n œ UP h ON H % N T Um T^^ ^wh U E Z ON Y N TON U h P h ON H g u T^ u =.3 g ^ n œ 785HLQD/&RQH&DUOR6G\

6 CD Allowed Region and inematical Reach for & tane=4 A =, µ> tanβ=4 AP (blue) h Vs. Previous Estimate (red) h m e m [GeV] 785HLQD/&RQH&DUOR6G\ GeV 4 GeV (5) b sγ 7 GeV (8) dark matter allowed GeV a µ < - m χ >m τ m / [GeV]

7 AP (blue) CD Allowed Region and inematical Reach for & h A =, µ> tanβ=5 Vs. A =, µ> tanβ=4 Previous Estimate (red) h tane=5 tane=4 tane= 8 A =, µ> tanβ= m [GeV] GeV 7 GeV GeV a µ < - m [GeV] GeV b sγ 7 GeV GeV a µ < - m [GeV] 6 4 m h 4 GeV a µ = - 9 GeV 4 b sγ dark matter allowed m χ >m τ 4 dark matter allowed dark matter allowed m / [GeV] m / [GeV] m / [GeV] 785HLQD/&RQH&DUOR6G\ m χ >m τ m χ >m τ

8 SUSY Signature at 5-GeV Linear Collider (LC5) Large tane scenario > 5 GeV = Next-to-LSP ÆNo + [3 + 3 GeV/c ] roduction! Æ + [+ GeV/c ] and [3+5 GeV/c ] 5 GeV Æ + E miss final state Same final state in + roduction/decay, BUT 785HLQD/&RQH&DUOR6G\

9 + E miss final state BUT, both jets could be very soft for small ' (between and ) in + roduction. V (e + e Æe + e ) 73 fb for T )>5 o and P T )> 3 GeV Æorward e + e tagging ÆActive mask Imortance of Active ask at LC E C e (GeV) [ o < T e +/ ) < 5.8 o ] T e + )>3 o, T e )>3 o T e +/ )>3 o, T e /+ )<3 o T e + )<3 o, T e )<3 o GeV 785HLQD/&RQH&DUOR6G\

10 onte Carlo Event Generator lus Beam Bremsstruhlung SUSY ISAET v7.63 e e Æ Æ Æ + E miss e e Æ Æ + E miss S PHACT v.ol (all 4 fermion final states (S4f) and rocess with e + /e olarization) e e Æ Q e Q e Q P Q P Q Q ; eeeeqq ( rocess) Ref E. Accomando and A. Ballestrero, Comut. Phys. Commun. 99, 7 (997) E. Accomando, A. Ballestrero, and E. aina, Comut. Phys. Commun. 5, 66 (3) Tau Decay TAUOLA v.6 Detector Simulation & Event Analysis Package LCD Root v3.5 AST C using LD ar detector arameterization, et inder, 785HLQD/&RQH&DUOR6G\

11 irst Set of msugra Points P >, tane = 4, A = ass (GeV) CPt m m / A A A HLQD/&RQH&DUOR6G\

12 V [ Br(Æ h ) [fb] s Pol(e ) =.9 5 GeV Pol(e ) = Pol(e ) =.9 S4f SUSY A A A HLQD/&RQH&DUOR6G\

13 at Pol.9(LH) N jet > (E jet > 3 GeV; ADE Y>.5) h ID (N track =, 3; q=+) q [ cost jet <.7 issing P T > 5 GeV.8 < cost(j, P vis ) <.7 Acolanarity > 4 o No E clusters in 5.8 o < T < 5.8 o with E > GeV No electrons in T > 5.8 o with P T >.5 GeV Beam mask o ( o ) o No E clusters with E > GeV Otimization of Event Selection Cuts Note cos(5.8 o )=.9, cos(5.8 o )=.995 at Pol.9(RH) N jet > (E jet > 3 GeV; ADE Y>.5) h ID (N track =, 3; q=+) _ cost jet _<.65 issing P T > 5 GeV.6 < cost(j, P vis ) <.6 Acolanarity > 4 o No E clusters in 5.8 o < T < 5.8 o with E > GeV No electrons in T > 5.8 o with P T >.5 GeV Beam mask o ( o ) o No E clusters with E > GeV 785HLQD/&RQH&DUOR6G\

14 Examle of Event Accetance A3 ('=) Pol(e ) = +.9 (L.H.) V Br(Æ h ) [fb] S S QQ 89.8 N > (E >3 GeV) q [ cost jet < issing P T > 5 GeV < cost(j, P vis ) < Acolanarity > 4 o No E clusters, No e Beam mask o N fb w/ o ( o ) 886 (886) 935 (935) 745 (74) 58 (5) 785HLQD/&RQH&DUOR6G\

15 ;< ; 9 CD < < 9 A ; A < L ;<! A A ; 9 ; A ;<! S ). ; T ; A. ; event 5 fb (tan tane=4) Pol.9(LH) Pol.9(RH) =>? L GI E GH E < <!! ; < E NH E NH " " ;9 ; O! 9 < L ; < ; ; < <A T< SR Q 3 P &% Y[Z V V QU U & + ( )* ) ( ( ' ' O _ O 9b _a` < ] ]^! 5.8 o./,,- S Q; S Q; S Q; _ O 9b _` & & &!. / A < ; _ O 9b _ < ` Y ^ Y!!.!. / * * S Q; S Q; S Q < _ O 9b _a` & & &.!. / rocess (i) qq means e e Æ eeqq (ii) ** means e e Æ ee 785HLQD/&RQH&DUOR6G\

16 HI <? C C>D < ; > T " V C >7 L? =? E = C " " " P n V P n C >7 L? = 9 ; [ = C " n P " n V 4 4 P " n 5 fb (tan tane=4) If we simly count the number of events, the significance is E AG >C AB = >? L V U QSR P N L! L > <Y > ) ( ' % & Q V ed acb \^]`_ AG [ >? Z,./ * +,.- * + QP l f l jk \ih E P gf " QP HI L? o q 9 m n E AG QP l gr jk \ih E P r QP N HI L? o q 9 m n E AG L >? =< Q V E d \]`st AG [ >? Z! QP w v jk \uh E P l ) ( ' % & QP HI L? o q 9 m n E AG " * 3- * 3- QP wg l jk \uh E P r l v QP N HI L? o q 9 m n E AG 5 785HLQD/&RQH&DUOR6G\

17 ass Determination Choose an effective mass of j, j and E miss, (j,j,e miss ), as a discriminator. Preare three temlates of the distribution of the effective mass for, and S. it a C samle of 5 fb with the three temlates to extract each contribution. 785HLQD/&RQH&DUOR6G\

18 (j,j,e miss ) Temlate unction itting with high statistics samles Æ 3 temlate functions Examle Pol(e)=.9(RH), '= GeV S S S itted (True ) ()= 36+7 ( 36) ()=47+7 (44) ()= 38+6 ( 377) 785HLQD/&RQH&DUOR6G\

19 (j,j,e miss ) with 5 fb Pol(e)=.9(RH) fb '= GeV '= GeV '=5 GeV itted (True ) = -33+ ( 36) =6+38 (44) = ( 377) itted (True ) = 4+7 ( 33) = (8) = (377) itted (True ) = 3+3 ( 6) =3+4 (4) =8+6 (377) 785HLQD/&RQH&DUOR6G\

20 (j,j,e miss fb Pol(e)=+.9(LH)[to] vs.9(rh)[bottom] Note should remain the same; shaes change little for the same olarization. Pol(e)=.9(RH) '= GeV '= GeV '=5 GeV Pol(e)=+.9(LH) S 785HLQD/&RQH&DUOR6G\

21 aking Temlate (using High-Stat. Samles) P(e)= )= RH-.9.9(RH) (j,j,emiss) [GeV] (stau)-(lsp) [GeV] 785HLQD/&RQH&DUOR6G\

22 '= GeV (j,j,e miss ) Distribution eak Æ Physics Extraction (j,j,e miss ) eak = 47+/?? Temlate RH-.9 itted (True ) = -33+ ( 36) =6+38 (44) = ( 377) V( ) area Cross section ( ) ( )=+/?? (j,j,emiss) [GeV] (stau)-(lsp) [GeV] '=+/?? ( )=YY+/?? 785HLQD/&RQH&DUOR6G\

23 History of TAU/Regina LC Studies O.. Signal.. Background SUSY 4f QQ S ee eeqq e beam olarization in. P T miss [GeV] Beam ask? Discrimination an. (ALCS -Chicago) O () - - LH No E -E Aug. (LCS) O - - LH No E miss an. 3 (ALCS3- Arlington) O - LH 5 o ( o ) E miss ar. 3 (SUGRA) O - O LH RH 5 o ( o ) E miss ul. 3 (ALCS3- Cornell) O O LH RH 5 o ( o ) (j,j,e miss ) uture 785HLQD/&RQH&DUOR6G\

24 Conclusion [ ] e investigated the cosmologically allowed msugra arameter sace using other ossible exerimental constraints, e.g., collider bounds, rare decay bounds. ÆOnly and roduction are kinematically allowed at 5-GeV and 8-GeV LCs. []e considered 3 different oints (' = 5,, GeV) in the arameter sace. ÆImortance of active mask to detect forward electron/ositron to suress events esecially for the small ' cases. Æ o mask will be effective at 5-GeV LC. 785HLQD/&RQH&DUOR6G\

25 Conclusion (Cont d) [4]Beam olarization for e ÆLH olarization to enhance the roduction. ÆRH olarization to reduce the S (QQ) events and to study the roduction. In this channel, we have the maximum reach for m / in the allowed region. [5]e roosed to use (j,j,e miss ) to extract the contributions from,, and S events. Our reliminary result shows that it is ossible to measure the and masses searately in a SUSY model. (ork is still in rogress.) [6]The arameter sace needs to be robed in details for 8- GeV LC. 785HLQD/&RQH&DUOR6G\

$Positon beam beam z 785HLQD/&RQH&DUOR6G\$

26 Event Toology Electron beam beam Positon Positon beam beam z 785HLQD/&RQH&DUOR6G\

27 + Event Toology Electron beam beam Positon Positon beam beam z 785HLQD/&RQH&DUOR6G\

28 (j,j,e miss ) for + & ( E, ) 3 & ( E, ) miss jje & & E E 5 4 & ( E, ) E & ( E, ) miss & & 5 & &, ( ) max miss jje max max max E E E & & & 5 785HLQD/&RQH&DUOR6G\

29 GeV E max '= GeV miss ) (j,j,e miss Pol(e)= )=.9(RH) E max jje max miss where E '= GeV E max E E / E beam '=5 GeV 785HLQD/&RQH&DUOR6G\

30 Discrimination Power for Staus with Pol(e )=.9 (RH) ith Our Standard Cuts for ALCS3-Arlington S eak (' 5) (' ) miss jje *H9 *H9 *H9 *H9 jj *H9 *H9 *H9 E miss *H9 *H9 *H9 *H9 785HLQD/&RQH&DUOR6G\

31 E miss miss [to] vs. (j,j,e miss )[bottom] Pol(e)= )=.9(RH) '= GeV '= GeV '=5 GeV 785HLQD/&RQH&DUOR6G\

32 (j,j ) Pol(e)= )=.9(RH) (j,j,e miss ) (j,j ) (' ) (' ) (' 5) 8 GeV GeV (j,j,e miss ) [vs. (j,j )] ÆClear end-oint for large '. 785HLQD/&RQH&DUOR6G\

Cosmology at the LHC

Cosmology at the LHC R. Arnowitt*, A. Aurisano*^, B. Dutta*, T. Kamon*, N. Kolev**, P. Simeon*^^, D. Toback*, P. Wagner*^ *Department of Physics, Texas A&M University **Department of Physics, Regina University