Dark Matter at the LHC: Understanding Experimental Reach

Transcription

1 Dark Matter at the LHC: Understanding Experimental Reach Thomas Jacques with G. Busoni, A. De Simone, S. Schramm, E. Morgante, A. Riotto Oslo

2 Dark Matter Searches Many forms of DM do interact with SM particles, just very weakly Several ways to search for these interactions, regardless of the underlying particle physics: Scattering: Direct Detection Production: Accelerator Searches SM Each technique has its own strengths and challenges Annihilation: Indirect Detection SM

3 Dark Matter Searches Collider Experiments WIMP Properties χχ Annihilation χn Interaction Relic Density Indirect Detection Direct Detection Astrophysical and Cosmological Inputs diagram courtesy of Anna Phan

4 Complementarity Cahill-Rowley et al. arxiv:

5 What exactly are we constraining? EFTs e.g. D1, M3 etc. operators Simplified Models e.g. Z, Scalar singlet DM Full Models e.g. MSSM, UED

6 ATLAS SUSY Searches* - 95% CL Lower Limits Status: ICHEP 014 Model e,µ,τ,γ Jets E miss T ATLAS Preliminary s =7,8TeV L dt[fb 1 ] Mass limit Reference Inclusive Searches 3 rd gen. g med. 3 rd gen. squarks direct production EW direct MSUGRA/CMSSM 0-6 jets Yes 0.3 m( q)=m( g) Current Status q, g 1.7 TeV MSUGRA/CMSSM 1 e,µ 3-6 jets Yes 0.3 g 1. TeV any m( q) ATLAS-CONF MSUGRA/CMSSM 0 7- jets Yes 0.3 g 1.1 TeV any m( q) q q, q q χ jets Yes 0.3 q 850 GeV m( χ 0 1)=0 GeV, m(1 st gen. q )=m( nd gen. q ) g g, g q q χ jets Yes 0.3 g 1.33 TeV m( χ 0 1)=0 GeV g g, g qq χ ± 1 qqw ± χ 0 1 e,µ jets Yes 0.3 g 1.18 TeV m( χ 0 1)<00 GeV, m( χ ± )=0.5(m( χ 0 1)+m( g)) ATLAS-CONF g g, g qq(ll/lν/νν) χ 0 e,µ jets g 1.1 TeV m( χ 0 1)=0GeV ATLAS-CONF GMSB ( l NLSP) e,µ -4 jets Yes 4.7 g 1.4 TeV tanβ< GMSB ( l NLSP) 1- τ + 0-1l 0- jets Yes 0.3 g 1.6 TeV tanβ > GGM (bino NLSP) γ - Yes 0.3 g 1.8 TeV m( χ 0 1)>50 GeV ATLAS-CONF GGM (wino NLSP) 1 e,µ+ γ - Yes 4.8 g 619 GeV m( χ 0 1)>50 GeV ATLAS-CONF GGM (higgsino-bino NLSP) γ 1 b Yes 4.8 g 900 GeV m( χ 0 1)>0 GeV GGM (higgsino NLSP) e,µ(z) 0-3 jets Yes 5.8 g 690 GeV m(nlsp)>00 GeV ATLAS-CONF Gravitino LSP 0 mono-jet Yes.5 F 1/ scale 645 GeV m( G)> 4 ev ATLAS-CONF g b b χ b Yes 0.1 g 1.5 TeV m( χ 0 1)<400 GeV g t t χ jets Yes 0.3 g 1.1 TeV m( χ 0 1) <350 GeV g t t χ e,µ 3 b Yes 0.1 g 1.34 TeV m( χ 0 1)<400 GeV g b t χ e,µ 3 b Yes 0.1 g 1.3 TeV m( χ 0 1)<300 GeV b 1 b 1, b 1 b χ b Yes 0.1 b m( χ GeV 1)<90 GeV b 1 b 1, b 1 t χ ± 1 e,µ(ss) 0-3 b Yes 0.3 b m( χ ± 1 )= m( χ GeV 1) t 1 t 1 (light), t 1 b χ ± 1 1- e,µ 1- b Yes 4.7 t m( χ GeV 1)=55 GeV , 109. t 1 t 1 (light), t 1 Wb χ 0 e,µ 1 0- jets Yes 0.3 t m( χ 0 1)=m( t 1 )-m(w)-50 GeV, m( t 1 )<<m( χ ± GeV 1 ) t 1 t 1 (medium), t 1 t χ 0 e,µ 1 jets Yes 0.3 t m( χ GeV 1)=1 GeV t 1 t 1 (medium), t 1 b χ ± 1 0 b Yes 0.1 t m( χ 0 1)<00 GeV, m( χ ± 1 )-m( χ GeV 1)=5 GeV t 1 t 1 (heavy), t 1 t χ 0 1 e,µ 1 1 b Yes 0 t m( χ 0 1 1)=0 GeV t 1 t 1 (heavy), t 1 t χ b Yes 0.1 t m( χ 0 1 1)=0 GeV t 1 t 1, t 1 c χ mono-jet/c-tag Yes 0.3 t m( t 1 )-m( χ 0 1 1)<85 GeV t 1 t t, t t 1 + Z 3 e,µ(z) 1 b Yes 0.3 t m( χ 0 1)<00 GeV SUSY searches, searches for missing -640 GeV energy, Fox searches GeV GeV t 1 t 1 (natural GMSB) e,µ(z) 1 b Yes GeV m( χ 0 1)>150 GeV etc GeV GeV l L,R l L,R, l l χ 0 1 e,µ 0 Yes 0.3 l m( χ 0 1)=0 GeV χ + 1 χ 1, χ + 1 lν(l ν) e,µ 0 Yes 0.3 χ ± GeV m( χ 0 1)=0 GeV, m( l, ν)=0.5(m( χ ± 1 )+m( χ 0 1 1)) χ + 1 χ 1, χ + 1 τν(τ ν) τ - Yes 0.3 χ ± GeV m( χ 0 1)=0 GeV, m( τ, ν)=0.5(m( χ ± 1 )+m( χ 0 1 1)) χ ± 1 χ0 l L ν l L l( νν),l ν l L l( νν) 3 e,µ 0 Yes 0.3 χ ± 700 GeV m( χ ± 1 )=m( χ 0 ), m( χ 0 1)=0, m( l, ν)=0.5(m( χ ± 1 )+m( χ 0 1)) , χ 0 χ ± 1 χ0 W χ 0 1Z χ 0-3 e,µ 1 0 Yes 0.3 χ ± 40 GeV m( χ ± 1 )=m( χ 0 ), m( χ 0 1)=0, sleptons decoupled , , χ 0 χ ± 1 χ0 W χ 0 1h χ 0 1 e,µ 1 b Yes 0.3 χ ± m( χ ± 1 )=m( χ 0 ), m( χ 0 1, χ 0 85 GeV 1)=0, sleptons decoupled ATLAS-CONF χ 0 χ0 3, χ 0,3 l R l 4 e,µ 0 Yes GeV m( χ 0 )=m( χ 0 3), m( χ 0 1)=0, m( l, ν)=0.5(m( χ 0 )+m( χ 0 1)) χ 0,3 Long-lived particles RPV Other χ ± 1 Direct χ + 1 χ 1 prod., long-lived χ ± 1 Disapp. trk 1 jet Yes GeV m( χ ± 1 )-m( χ 0 1)=160 MeV, τ( χ ± 1 )=0. ns ATLAS-CONF Stable, stopped g R-hadron jets Yes 7.9 g 83 GeV m( χ 0 1)=0 GeV, µs<τ( g)<00 s GMSB, stable τ, χ 0 1 τ(ẽ, µ)+τ(e,µ) 1- µ χ GeV <tanβ<50 1 ATLAS-CONF GMSB, χ 0 1 γ G, long-lived χ 0 1 γ - Yes 4.7 χ 0 30 GeV 0.4<τ( χ 0 1)< ns q q, χ 0 1 qqµ (RPV) 1 µ, displ.vtx q 1.0 TeV 1.5 <cτ<156 mm, BR(µ)=1, m( χ 0 1)=8 GeV ATLAS-CONF LFV pp ν τ + X, ν τ e + µ e,µ ν λ 311 =0., λ τ 1.61 TeV 13= LFV pp ν τ + X, ν τ e(µ) + τ 1 e,µ+ τ ν λ 311 =0., λ τ 1.1 TeV 1()33= Bilinear RPV CMSSM e,µ(ss) 0-3 b Yes 0.3 q, g 1.35 TeV m( q)=m( g), cτ LS P <1mm χ + 1 χ 1, χ + 1 W χ 0 1, χ 0 1 ee ν µ, eµ ν e 4 e,µ - Yes 0.3 χ ± m( χ 0 1)>0. m( χ ± GeV 1 ), λ χ + 1 χ 1, χ + 1 W χ 0 1, χ 0 1 ττ ν e, eτ ν τ 3 e,µ+ τ - Yes 0.3 χ ± m( χ 0 1)>0. m( χ ± GeV 1 ), λ g qqq jets g 916 GeV BR(t)=BR(b)=BR(c)=0% ATLAS-CONF g t 1 t, t 1 bs e,µ(ss) 0-3 b Yes 0.3 g 850 GeV Scalar gluon pair, sgluon q q 0 4jets sgluon 0-87 GeV incl. limit from Scalar gluon pair, sgluon t t e,µ(ss) b Yes 14.3 sgluon GeV ATLAS-CONF WIMP interaction (D5, Dirac χ) 0 mono-jet Yes.5 M* scale 704 GeV m(χ)<80 GeV, limit of<687 GeV for D8 ATLAS-CONF s =7TeV full data s =8TeV partial data s =8TeV full data 1 1 Mass scale [TeV] *Only a selection of the available mass limits on new states or phenomenaisshown.alllimitsquotedareobservedminus1σ theoretical signal cross section uncertainty.

7 ATLAS Exotics Searches* - 95% CL Exclusion Status: ICHEP 014 Model l, γ Jets E miss T ATLAS Preliminary L dt = ( ) fb 1 s = 7, 8 TeV L dt[fb 1 ] Mass limit Reference Extra dimensions Current ADD G KK + g/q 1- Status j Yes 4.7 n = M D 4.37 TeV ADD non-resonant ll e, µ 0.3 M S 5. TeV n =3HLZ ATLAS-CONF ADD QBH lq 1 e, µ 1j 0.3 M th 5. TeV n = ADD QBH j 0.3 M th 5.8 TeV n =6 to be submitted to PRD ADD BH high N trk µ (SS) 0.3 M th 5.7 TeV n =6, M D =1.5TeV, non-rot BH ADD BH high p T 1 e, µ j 0.3 M th 6. TeV n =6, M D =1.5TeV, non-rot BH RS1 G KK ll e, µ 0.3 G KK mass.68 TeV k/m Pl = RS1 G KK WW lνlν e, µ Yes 4.7 G KK mass 1.3 TeV k/m Pl = Bulk RS G KK ZZ llqq e, µ j/1j 0.3 G KK mass 730 GeV k/m Pl =1.0 ATLAS-CONF Bulk RS G KK HH b bb b 4b 19.5 G KK mass GeV k/m Pl =1.0 ATLAS-CONF Bulk RS g KK tt 1 e, µ 1 b, 1J/j Yes 14.3 g KK mass.0 TeV BR = 0.95 ATLAS-CONF S 1 /Z ED e, µ 5.0 M KK R TeV UED γ Yes 4.8 Compact. scale R TeV ATLAS-CONF Gauge bosons CI DM LQ Heavy quarks Excited fermions Other SSM Z ll e, µ 0.3 Z mass.9 TeV SSM Z ττ τ 19.5 Z mass 1.9 TeV ATLAS-CONF SSM W lν 1 e, µ Yes 0.3 W mass 3.8 TeV ATLAS-CONF EGM W WZ lν l l 3 e, µ Yes 0.3 W mass 1.5 TeV EGM W WZ qqll e, µ j/1j 0.3 W mass 1.59 TeV ATLAS-CONF LRSM W tb R 1 e, µ b, 0-1 j Yes 14.3 W mass 1.84 TeV ATLAS-CONF LRSM W tb R 0 e, µ 1 b, 1 J 0.3 W mass 1.77 TeV to be submitted to EPJC CI qqqq j 4.8 Λ 7.6 TeV η = CI qqll e, µ 0.3 Λ 1.6 TeV η LL = 1 ATLAS-CONF CI uutt e, µ (SS) 1 b, 1 j Yes 14.3 Λ 3.3 TeV C =1 ATLAS-CONF EFT D5 operator (Dirac) 0 e, µ 1- j Yes.5 M 731 GeV at 90% CL for m(χ) < 80 GeV ATLAS-CONF EFT D9 operator (Dirac) 0 e, µ 1J, 1 j Yes 0.3 M.4 TeV at 90% CL for m(χ) < 0 GeV Scalar LQ 1 st gen e j 1.0 LQ mass 660 GeV β = Scalar LQ nd gen µ j 1.0 LQ mass 685 GeV β = Scalar LQ 3 rd gen 1 e, µ, 1τ 1b,1j 4.7 LQ mass 534 GeV β = Vector-like quark TT Ht + X 1 e, µ b, 4 j Yes 14.3 T mass 790 GeV T in (T,B) doublet ATLAS-CONF Vector-like quark TT Wb + X 1 e, µ 1 b, 3 j Yes 14.3 T mass 670 GeV isospin singlet ATLAS-CONF Vector-like quark TT Zt + X / 3 e, µ / 1 b 0.3 T mass 735 GeV T in (T,B) doublet ATLAS-CONF Vector-like quark BB Zb + X / 3 e, µ / 1 b 0.3 B mass 755 GeV B in (B,Y) doublet ATLAS-CONF Vector-like quark BB Wt + X e, µ (SS) 1 b, 1 j Yes 14.3 B mass 70 GeV B in (T,B) doublet ATLAS-CONF Excited quark q qγ 1 γ 1j 0.3 q mass 3.5 TeV only u and d, Λ = m(q ) Excited quark q qg j 0.3 q mass 4.09 TeV only u and d, Λ = m(q ) to be submitted to PRD Excited quark b Wt 1 or e, µ 1 b, j or 1 j Yes 4.7 b mass 870 GeV left-handed coupling Excited lepton l lγ e, µ, 1γ 13.0 l mass. TeV Λ =.TeV LSTC a T W γ 1 e, µ, 1γ Yes 0.3 a T mass 960 GeV to be submitted to PLB LRSM Majorana ν e, µ j.1 N 0 mass 1.5 TeV m(w R )=TeV, no mixing Type III Seesaw e, µ 5.8 N ± mass 45 GeV V e =0.055, V µ =0.063, V τ =0 ATLAS-CONF Higgs triplet H ±± ll e, µ (SS) 4.7 H ±± mass 409 GeV DY production, BR(H ±± ll)= Multi-charged particles 4.4 multi-charged particle mass 490 GeV DY production, q =4e Magnetic monopoles.0 monopole mass 86 GeV DY production, g =1g D s = 7 TeV s = 8 TeV *Only a selection of the available mass limits on new states or phenomena is shown. 1 1 Mass scale [TeV]

8 What exactly are we constraining? EFTs e.g. D1, M3 etc. operators Simplified Models e.g. Z, Scalar singlet DM Full Models e.g. MSSM, UED

9 Effective Field Theories q q q q g a g b Q tr M = g ag b M 1+ Q tr M + O Q 4 tr M 4 ' 1 D1 = ( )( qq) D5 = ( µ )( q µ q) M1 = ( C1 = ( )( qq) )( qq) D8 = ( µ 5 )( q µ 5 q) C3 = µ )( q µ q)

10 q q! Complementarity q q! N! N N!N! q q!q q / s] 3 Annihilation rate <σv> for χχ qq [cm ATLAS 1 ( Fermi-LAT dsphs (χ χ ) bb ) Majorana D5: qq (χχ) Dirac D8: qq (χχ) -1 σ theory Dirac s = 7 TeV, 4.7 fb WIMP mass m χ [ GeV ] -1, 95%CL Thermal relic value ATLAS JHEP 1304, 075 (013) 3 ] WIMP-Nucleon cross section [ cm ATLAS XENON0 01 CDMSII low-energy CoGeNT 0 D5: CDF qq j(χχ) Dirac 1 s -1 = 7 TeV, 4.7 fb, 90%CL D1: qq j(χχ) D5: qq j(χχ) D11: gg j(χχ) -1 σ theory ATLAS JHEP 1304, 075 (013) Dirac Dirac Spin-independent Dirac WIMP mass m χ [ GeV ] 3

11 CMS: Results at 7 and 8 T And Finally... Effective Operators and Direct Detection 9! Sushil S. Chauhan! Robyn Lucas Mono-photons 7 TeV results were the first bound from They are good benchmarks that describe (with appropriate combinations of Useful benchmark, but we must- be cut clear & countabout based limits what this interactions) the heavy mass limit of every simplified model. actually means! TeV almost an point. order of magni But remember: these plots are a lot of 8fun, butlimits they re not the

12 Effective Operators and Direct Detection Direct detection constrains the recoil energy spectrum; The form depends on the non-relativistic limit of the operator. For example, the usual Spin Independent form: dr de R = SI (Z + f n (A Z)) F (E R ) m µ N f p applies to the the NR-limit of these operators: Z 1 v min 0 f(~v ) ~v d3 v ( )( NN),( µ )( N N), $ µ )( N µ µ ( )( NN), N) Similarly, spin dependent scattering comes from operators: ( µ 5 )( N µ 5 N), ( µ )( N µ N)

13 Effective Operators and Direct Detection µ N µ N = f ( µ q µ q) NN = f qq, G a µ G a µ + q S V q q q g g µ N µ N = f( µ q µ q) NN = f( qq, G a µ G a µ ) + q V q q S q g g

14 Effective Operators and Direct Detection ( )( qq) ( µ )( q µ q) ( )(G a µ Gµ )} a! ( )( qq) SI! ( µ )( q µ q) ( )(G a µ G a µ )

15 ] χ-nucleon Cross Section [cm CMS Preliminary s = 8 TeV L dt = 19.5 fb -1 CMS 01 Vector CMS 011 Vector CDF 01 XENON0 01 COUPP 01 SIMPLE 01 CoGeNT 011 CDMSII 011 CDMSII 0-9 CAUTION! XENON0 01 Spin Independent -31 CDMSII low-energy CoGeNT 0 M χ [GeV/c ] D5: CDF qq j(χχ) -1 σ Dirac theory ] WIMP-Nucleon cross section [ cm µ χ)(qγ q) mits on the dark matter-nucleon cross section tor with CDF [54], SIMPLE [55], CDMS [1], d for the axial-vector operator with CDF [54], ] y CMS 01 Vector CMS 01 Scalar (χγ µ Λ -45 ATLAS 1 s -1 = 7 TeV, 4.7 fb, 90%CL D1: qq j(χχ) D5: qq j(χχ) D11: gg j(χχ) Dirac Dirac Spin-independent Dirac WIMP mass m χ [ GeV ] 3

16 Collider Searches! Excellent Discovery potential, but Hard to interpret results independently of a specific model (although can constrain effective operators) Fundamental limit on DM mass reach Needle in a haystack

17 Fundamental Limit to Validity In s-channel: Q tr > m DM q M>m DM = p M ga g b M 4 q & m DM

18 Effective Field Theories q jet, γ, etc. q jet, γ, etc. q q g a g b Q tr M = g ag b M 1+ Q tr M + O Q 4 tr M 4 ' 1 & m DM Q tr <M

19 Effective Field Theories EFT approximation:! M g a g b Best case scenario:! p ga g b ' 4, Q tr. 4 Reasonably robust scenario: g a g b ' 1, Q tr. Q tr <

20 Measuring the Validity Calculate or measure the fraction of events that pass the condition Qtr < Λ, for a given choice of Λ and mdm tot R D1 = ( )(q q) = q q! e >Qtr e + jet Qtr = pq + pq pjet G. Busoni, A. De Simone, J. D1 Gramling, E. Morgante, A. Riotto s = 8 Te V arxiv: Ge V p T 1 Te V,»h» VD VD 500 RLtot = 75% RLtot = 50% RLtot = 5% RLtot = % L < m DM m VD

21 Extension to t-channel 1 ( P Lq)( qp R ) jet etc. Two definitions of the momentum transfer: Q tr = p q p, or p q p p jet q s =14TeV 500GeV p T TeV, h R L = 75 % R L = 50 % R L = 5 % R L = % W DM h =0.1 q q q 0 3 m jet etc.

22 Fierz Transform 1 ( P Lq)( qp R ) = )= ( µp R )( q µ P L q) ( µp R )( q µ P L q) s =14TeV 500GeV p T TeV, h R L = 75 % R L = 75 % R L = 75 % R L = 75 % L < m DM 0 3 m D8 s = 14 TeV 500GeV p T TeV,»h» D5 s = 14 TeV 500GeV p T TeV,»h» R L tot = 75% R L tot = 50% R tot L = 5% R tot L = % R L tot = 75% R L tot = 50% R L tot = 5% R L tot = % m L < m DM m L < m DM

23 [GeV] * Suppression scale M Effective Field Theories Operator D5, SR3, 90%CL Expected limit (± Observed limit (± ATLAS Preliminary s=8 TeV 1 ± σ exp ) 1σ theory ) Ldt =.5 fb -1 EFT Validity R R R * R tot Thermal relic Operator D5, SR3, 90%CL effective theory not valid ATLAS Preliminary 3-1 s=8 TeV WIMP Ldt = mass.5 fbm χ [GeV] = e >Qtr Expected limit (± Observed limit (± Thermal relic 1 ± e σ exp ) 1σ theory ) Operator D11, SR3, 90%CL Expected limit (± 1 ± σ exp ) Observed limit (± Thermal relic ATLAS Preliminary effective theory not valid s=8 TeV [GeV] * Suppression scale M σ theory ) Operator D8, SR3, 90%CL Expected limit (± Observed limit (± Thermal relic 1 ± ATLAS Preliminary s=8 TeV Ldt =.5 fb -1 σ exp ) 1σ theory ) effective theory not valid -1 Ldt =.5 fb WIMP mass m χ [GeV] 3 effective theory not valid WIMP mass m χ 3 [GeV]

24 Rescaling the Limits [%] tot R Mmed 0 80 ATLAS Simulation Preliminary M* [TeV] ATLAS Simulation Preliminary s = 8 TeV - 1 = 50 GeV L = 0 fb miss E T miss E T miss E T > 400 GeV > 600 GeV > 800 GeV g g SM DM m χ ATL-PHYS-PUB D s = 8 TeV - 1 = 50 GeV L = 0 fb miss E T miss E T miss E T > 400 GeV > 600 GeV > 800 GeV M* valid M* exp g g SM DM m χ D5 p gsm g DM For a given, cut all events that don t pass M p g SM g DM Q tr

25 Rescaling the Limits - 14TeV [%] tot R Mmed ATLAS Simulation Preliminary s = 14 TeV - 1 = 50 GeV L = 5 fb g g SM DM m χ ATL-PHYS-PUB miss E T miss E T miss E T > 400 GeV > 600 GeV > 800 GeV D5 M* [TeV] ATLAS Simulation Preliminary s = 14 TeV - 1 = 50 GeV L = 5 fb miss E T miss E T miss E T > 400 GeV > 600 GeV > 800 GeV M* valid M* exp g g SM DM m χ D5 p For a given gsm g DM, cut all events that don t pass M p g SM g DM Q tr

26 Effective Operators and Direct Detection ] WIMP-nucleon cross section [cm ATLAS D1: χ χ q q µ D5: χ γ χqγ D11: χ χ G q µ µν G µν truncated, coupling = 1 truncated, max coupling spin-independent 1 90% CL -1 s=8 TeV, 0.3 fb C1: χ χq q C5: χ χg µν G µν DAMA/LIBRA, 3σ CRESST II, σ CoGeNT, 99% CL CDMS, 1σ CDMS, σ CDMS, low mass LUX % CL Xenon0 90% CL CMS 8TeV D5 CMS 8TeV D11 WIMP mass m χ [GeV] 3 ] WIMP-nucleon cross section [cm ATLAS µ 5 5 D8: χ γ γ χqγ γ q µ µν D9: χ σ χqσ µν q truncated, coupling = 1 truncated, max coupling spin-dependent 1 90% CL -1 s=8 TeV, 0.3 fb COUPP 90% CL SIMPLE 90% CL PICASSO 90% CL Super-K 90% CL + - IceCube W W 90% CL CMS 8TeV D8 WIMP mass m χ [GeV] 3 (b) 6 ]

27 So what now? EFTs e.g. D1, M3 etc. operators Simplified Models e.g. Z, Scalar singlet DM Full Models e.g. MSSM, UED

28 q Moving to Simplified Models We are now confronted with both a broad model-space and parameterspace q q S Inevitably choices must be made, but this can be minimized S Avoid models that have been ruled out by DD q q Start with models that are good DM candidates: V,S If we see new physics at the LHC, how can we test whether it s actually the DM? q Can the DM motivation for WIMP searches, help us focus on the best search regions?

29 Relating WIMP searches to DM 1. DM is a thermal relic, so that relic density goes like. The dominant annihilation channel is to SM fermions via one dark mediator; obs DMh '.5 GeV h vi ann 3. gu,d gq,l 4. The DM candidate makes up 0% of the DM of the universe

30 3 & 4. Annihilation Range Allowing DM to couple to either just one generation of quarks, or all fermions, gives a range for the annihilation rate 3: h vi ann h vi!uū + h vi!d d h vi min 4: X X h vi ann apple h vi min + quarks leptons 1 3 h vi min GeV. h vi min GeV

31 Effective operator results D5 = 1 4 ( µ )( q µ q) / % [ ] / % / % [ ]

32 Effective operator results D8 = 1 4 ( µ 5 )( q µ 5 q) / % [ ] / % / % [ ]

33 Effective operator results D8 = 1 4 ( µ 5 )( q µ 5 q) % % % [ ] % % % % % [ ]

34 Relaxing the final assumption [ ] / / / [ ] [ ] / / / [ ]

35 Resonances & Widths 90% CL limit on Λ [GeV] CMS Preliminary s = 8 TeV L dt = 19.5 fb -1-1 µ (χγ χ)(qγ q) µ Λ m χ =500 GeV/c, Γ=M/3 m χ =500 GeV/c, Γ=M/ m χ =500 GeV/c, Γ=M/8π m χ =50 GeV/c, Γ=M/3 m χ =50 GeV/c, Γ=M/ m χ =50 GeV/c, Γ=M/8π CMS EXO PAS 1 Mediator Mass M [TeV/c ] Resonance strengthens constraints relative to EFT, but width adds more parameters Opens mediator searches Min width fixed by the model: Beware arbitrary widths Introduces gq/gdm as a free parameter

36 Treatment of the width = = - = = - ( / ) - = = ( / )

37 Results Results

38 Conclusion At LHC energies, Effective Field Theories are a powerful tool but must be interpreted with caution Naive EFT constraints remain fully valid only for large couplings Thermal relic DM can be a powerful motivator for WIMP searches at the LHC