Shufang Su • U. of Arizona SuperWIMP Dark matter Gravitino from Slepton and Sneutrino Decays Shufang Su • U. of Arizona J. Feng, F. Takayama, S. Su Hep-ph/0404198

Outline SWIMP dark matter and gravitino LSP - SWIMP dark matter and gravitino LSP Late time energy injection and BBN Slepton and sneutrino NLSP Dominant two body EM decay l ! l+G Subdominant 3-body hadronic decay Viable parameter space Conclusion ~ S. Su SWIMP

Why gravitino not considered as CDM usually? - 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

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 104 s  t  108 s NLSP  G + SM particles ~ Neutralino/Chargino NLSP Slepton NLSP BBN EM had Brhad  O(0.01) Brhad  O(10-3) S. Su SWIMP

Different approach to gravitino superWIMP - ~ NLSP  G + SM particles my talk Takayama’s talk SWIMP close universe SWIMP maybe insiginificant nNLSP  NLSP/mNLSP  1/mSUSY thNLSP  v-1  m2SUSY  nNLSP  mSUSY NLSP: slepton,sneutrino NLSP: slepton, sneutrino, neutralino fix SWIMP = 0.23 SWIMP = mG/mNLSP thNLSP ~ S. Su SWIMP

Late time energy injection and BBN - /10-10 = 6.1 0.4 ? EM,had=EM,had BEM,had YNLSP EM, had energy injection: » mNLSP-mG Fields, Sarkar, PDG (2002) S. Su SWIMP

EM and Had BBN constraints - EM BBN constraints had BBN constraints EM BBN Cyburt, Ellis, Fields and Olive, PRD 67, 103521 (2003) Kawasaki, Kohri and Moroi, astro-ph/0402490 S. Su SWIMP

Slepton NLSP lifetime and EM injection - l  G + l,  ! G +  ~ Decay lifetime (sec) EM energy injection EM (GeV) S. Su SWIMP

Hadronic decay branching ratio - l  lZG,WG ,  ! ZG, lWG ~ meson contribution mNLSP S. Su SWIMP

Viable Parameter space - 200 GeV ·  m · 400 » 1500 GeV mG ¸ 200 GeV  m · 80 » 300 GeV ~ negligible EM BBN constraints S. Su SWIMP

Conclusions SuperWIMP is possible candidate for dark matter - SuperWIMP is possible candidate for dark matter SUSY models: gravitino LSP (SWIMP) slepton NLSP (WIMP) Constraints from BBN: EM injection and hadronic injection need updated studies of BBN constraints on hadronic/EM injection Favored mass region: (enlarged if SWIMP<0.23) Sneutrino:  m  80-300 GeV  m  100 GeV Charged R: 200 GeV ·  m · 1500 GeV, mG ¸ 200 GeV  500 GeV  mR Rich collider phenomenology (no direct/indirect DM signal) Charged slepton: highly ionizing track Sneutrino: missing energy ~ ~ ~ ~ ~ S. Su SWIMP

SM energy distribution Decay life time  mpl SM energy distribution  mG  SUSY breaking scale SM NLSP ~ G SM NLSP ~ SM NLSP ~ G ~ G NLSP SM SM NLSP ~ G ~ G S. Su SWIMP