Shufang Su • U. of Arizona SuperWIMP Dark matter in SUSY with a Gravitino LSP Shufang Su • U. of Arizona See also, Jonathan Feng’s talk, SuperWIMPs and Slepton Traps J. Feng, F. Takayama, S. Su hep-ph/0404198, 0404231

Why is the gravitino not usually considered as DM? - In supergravity, for mG » GeV – TeV ~ thG  v-1  (gravitional coupling)-2 (comparig to WIMP of weak coupling strength) v too small thG too big, overclose the Universe ~ However, gravitino can get relic density by other means SuperWIMP S. Su SWIMP

WIMP  SWIMP + SM particle - FRT hep-ph/0302215, 0306024 WIMP 104 s  t  108 s SWIMP SM  Gravitino LSP  LKK graviton 106 S. Su SWIMP

Outline SWIMP dark matter and gravitino LSP Constraints - SWIMP dark matter and gravitino LSP Constraints Late time energy injection and BBN NLSP  gravitino +SM particle slepton, sneutrino, neutralino - approach I: fix SWIMP=0.23 - approach II: SWIMP=(mSWIMP/mNLSP) thNLSP Collider phenomenology Conclusion Updates since Jan SLAC LC workshop S. Su SWIMP

SWIMP and SUSY WIMP SWIMP: G (LSP) WIMP: NLSP mG » mNLSP ~ SUSY case - SWIMP: G (LSP) WIMP: NLSP mG » mNLSP ~ SUSY case ~ Ellis et. al., hep-ph/0312262; Wang and Yang, hep-ph/0405186. 104 s  t  108 s NLSP  G + SM particles ~ neutralino/chargino NLSP slepton/sneutrino NLSP BBN EM had Brhad  O(0.01) Brhad  O(10-3) S. Su SWIMP

Constraints ~ NLSP  G + SM particles  Dark matter density G · 0.23 - ~ NLSP  G + SM particles /10-10 = 6.1 0.4 Fields, Sarkar, PDG (2002)  Dark matter density G · 0.23 ~ - approach I: fix SWIMP=0.23 - approach II: SWIMP=(mSWIMP/mNLSP) thNLSP  CMB photon energy distribution  Big bang nucleosynthesis Late time EM/had injection could change the BBN prediction of light elements abundances S. Su SWIMP

BBN constraints on EM/had injection - Decay lifetime NLSP EM/had energy release EM,had=EM,had BrEM,had YNLSP Cyburt, Ellis, Fields and Olive, PRD 67, 103521 (2003) EM EM (GeV) » mNLSP-mG ~ Kawasaki, Kohri and Moroi, astro-ph/0402490 had EM S. Su SWIMP

YNLSP: approach I approach I: fix G = 0.23 ~ slepton and sneutrino - approach I: fix G = 0.23 ~ slepton and sneutrino 200 GeV ·  m · 400 » 1500 GeV mG ¸ 200 GeV ~  m · 80 » 300 GeV apply CMB and BBN constraints on (NLSP, EM/had )  viable parameter space NLSP, EM,had=EM,had BEM,had YNLSP S. Su SWIMP

Approach II: slepton and sneutrino - G = (mG/mNLSP) thNLSP ~ S. Su SWIMP

Distinguish from stau NLSP and gravitino LSP in GMSB Collider Phenomenology - SWIMP Dark Matter no signals in direct / indirect dark matter searches SUSY NLSP: rich collider phenomenology NLSP in SWIMP: long lifetime  stable inside the detector Charged slepton highly ionizing track, almost background free Distinguish from stau NLSP and gravitino LSP in GMSB GMSB: gravitino m » keV warm not cold DM collider searches: other sparticle (mass) (GMSB) ¿ (SWIMP): distinguish experimentally Feng and Smith, in preparation. S. Su SWIMP

Sneutrino and neutralino NLSP - sneutrino and neutralino NLSP missing energy signal: energetic jets/leptons + missing energy  Is the lightest SM superpartner sneutrino or neutralino? angular distribution of events (LC) vs.  Does it decay into gravitino or not? sneutrino case: most likely gravitino is LSP neutralino case: most likely neutralino LSP direct/indirect dark matter search positive detection  disfavor gravitino LSP precision determination of SUSY parameter: th, ~ ~ ,  0.23  favor gravitino LSP ~ S. Su SWIMP

SM energy distribution  Mpl Decay life time SM energy distribution  Mpl  mG  SUSY breaking scale ~ SM NLSP ~ G NLSP SM SM NLSP ~ G Capture particle: Goity, Kossler and Sher, hep-ph/9305244 ~ G SM NLSP NLSP SM ~ G Supergravity at colliders Buchmuller et. al. hep-ph/0402179 ~ G SWIMPs and slepton traps Feng and Smith In preparation… See Feng’s talk S. Su SWIMP

Conclusions SuperWIMP is possible candidate for dark matter - SuperWIMP is possible candidate for dark matter SUSY models SWIMP: gravitino LSP WIMP: slepton/sneutrino/neutralino Constraints from BBN: EM injection and hadronic injection need updated studies of BBN constraints on hadronic/EM injection Favored mass region Approach I: fix G=0.23 Approach II: G = (mG/mNLSP) thNLSP Rich collider phenomenology (no direct/indirect DM signal) charged slepton: highly ionizing track sneutrino/neutralino: missing energy Other implications … ~ ~ ~ S. Su SWIMP