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Light Neutralino Dark Matter ( in the NMSSM). Zhen Liu with Tao Han and Shufang Su, to appear. Motivation. What’s the next scale? well-defined “Just around the corner”. Motivation. Next scale? One direction at a time
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Light Neutralino Dark Matter (in the NMSSM) Zhen Liu with Tao Han and Shufang Su, to appear
Motivation What’s the next scale? • well-defined “Just around the corner”
Motivation • Next scale? One direction at a time • We look at the new physics scale around 10 GeV that is related to dark matter (similarly to Hooman) • We would like to consider • “the most beloved” SUSY models. • It is highly constrained highly predictable.
Motivation Fermi-LAT T.Han, ZL, A. Natarajan 1303.3040
Neutralino LSP in the NMSSM Neutralino LSP serves as good DM candidate in R-parity conserving SUSY models A mixture of Bino, Wino, Higgsino and Singlino
Higgs Sector in the NMSSM For discussion about Low-mass Higgs states, see our work N.Christensen, T. Han, ZL and S. Su, 1303.2113
Light Neutralino LSP Vanishes when tan\beta=1, or large mu Bino and Singlino are pretty inert Couplings to Z boson proportional to Couplings to Higgs boson: Only care about LSP and ignore Binocouples to particles with baryon numbers (s)fermions and gauge interaction through their Higgsino component. Singlinocouples to particles through singlet Higgs bosons, or MSSM Higgs Bosons through Higgsino component.
Neutralino LSP in the NMSSM Want ~10 GeV (<30 GeV) LSP LEP tells us a lot Chargino Constrains (excluded to ~100 GeV with mass splitting greater than 3 GeV; >70 GeV with small mass splitting at L3) Wino and Higgsino away from 10 GeV Bino-like, Singlino-like or Mixture.
Light Neutralino LSP Ways out if assuming thermal relic Famous “Funnel” regions to hit the s-channel resonance for the mediator. Especially near the PQ-limit NMSSM, automatically light CP-odd singlet like Higgs. Famous “Co-annihilation” regions to have sfermions in thermal equilibrium help LSP annihilate efficiently. Dark Light Higgs, P.Drapper, T.Liu, C.Wagner, L-T. Wang and H.Zhang A.Arbey, M.Battagliaand F.Mahmoudi, 1205.2557
(In)Famous Solutions Looking away from the corner Are they Okay with current constraints? Looking away from/around the corner How about the detection perspectives?
Z Boson v.s. Solutions An example of Partial and Total Widths matters a lot! For co-annihilation, sfermion NLSP Theoretical uncertainties: ~0.5 MeV, Freitas,1310.2256 Z decoupling
Finding the Solutions LEP constrains on light Higgs bosons, light sfermions and Z boson precision measurements Higgs bosons constrains from the LHC B-physics and electroweak precision constraints, including Upsilon(1S) decays Relic density LUX direct detection constrain Enforced!
Finding the Solutions Using modified NMSSMTools4 Multiple way of scanning: General Dedicated Seeded Log prior used for several dedicated scans
Haivng found solutionsmore fun to discuss about them… Z Boson Width: LSP pair Sbottom pair Stau pair Preliminary from now on!
Relic Abundance: Funnel Not over-abundant + LUX + Not under-abundant Fixed sbottom mass Co-annihilation
Direct Detection Resonant! Not over-abundant + scaled with relic density + LUX + Not under-abundant Fixed sbottom mass
Indirect Detection Not over-abundant + scaled with relic density + LUX + Not under-abundant Solid/dashed lines: Exclusion from Fermi-LAT from inner galaxy assuming DM annihilate to bottom pair/ tau pair assuming NFW profile
gg h diphoton 126 GeVHiggs Boson! Not much Enhanced Diphoton Stau, sbottom loop doesn’t contribute much in our case as one expected from limits of Br of Higgs. ggh WW,ZZ Exotic decays Up to 30% May have triggering issue. See discussions by the Exotic Higgs Decay working group, to appear
Light h1 properties Production, funnel in general at least factor of a few is larger than coannihilationbecause of necessary SM decays. Mainly bottom pairs tau pairs. Decay to LSP pairs kinematically suppressed as well as required by efficient annihilation.
Sfermions? • Light with compressed spectrum. • Minimized couplings to the Z boson. • Consider the light sbottom at the LHC: • QCD production, huge cross section • Sbottom decays: • Prompt if sbottombottom+LSPkinematically allowed; • Can be prompt, R hadrons, displaced depending on flavor structure if bottom+LSP decay mode forbidden; • We discuss about possibilities and perform studies to compare with experiment.
SbottomSearches Pair Production Tracy back in History; No mixing independent constraints delta_m<7 GeV
SbottomSearches Z decoupling
Finding the Sbottom • Mono-everything searches? • We recast the study with ATLAS analysis. Choosing a benchmark with Sbottom mass 20 GeV LSP mass 14 GeV Bottom mass 4.2 GeV • (At tree level) It decays promptly as long as LSP not “pure” Singlino. • Mono-b: • T.Lin, E.Kolband L.-T.~Wang 1303.6638
Recast and compare Sbottom pair + jet Sbottom pair Prompt light sbottom decays to bottom + LSP excluded!
Summary • We discuss about • ~10 GeVneutralino DM in NMSSM • Solutions are either a1,h1-funnel or sfermion co-annihilation • Constrains carefully studied and discussed about possible collider searches. • Recast the ATLAS searches for sbottom pair production for compressed spectra and find prompt sbottom to bottom+LSP excluded.
Finetuning? Showed up in many places • Resonance • Co-annihilation small mass splitting • Z decoupling • (not necessarily) hitting resonance for direct detection.