Radiative natural SUSY with mixed axion-higgsino CDM Howie Baer University of Oklahoma ``The imagination of nature is far, far greater than that of man : a data-driven approach to where SUSY might be hiding 1
LHC Higgs signal now 5σ discovery! m h 125 GeV Excess of events also reported from CDF/D0 2
Higgs mass in SM: m HSM 115 800 GeV Higgs in MSSM: h, H, A, H ± m h 115 135 GeV Data from LHC: Higgs-like resonance @~125 GeV confirms MSSM prediction! 3
m(h)~125 GeV requires m(t1,t2)~tev range and large mixing in MSSM 4
But where are the SUSY particles? Latest Atlas/CMS search results in msugra [GeV] m 1/2 500 1000 1500 2000 2500 3000 Atlas/CMS: no sign of msugra at LHC7: 800 700 600 500 400 300 200 100 = LSP " # CMS Preliminary m(q ~ ) = 1500 Jets+MHT m(q ~ ) = 1000 SS Dilepton m(g ~ ) = 500 Razor OS Dilepton % T Multi-Lepton L int m(q ~ ) = 2000-1 = 4.98 fb, m(g ~ ) = 1500 MT2 1 Lepton m( ~ q) = 2500 s = 7 TeV tan($)=10 A 0 µ > 0 m t = 0 GeV = 173.2 GeV ~ LEP2 l m 0 ± " LEP2! ± 1 m(g ~ ) = 1000 Non-Convergent RGE's No EWSB [GeV] m g > 1400 GeV for m q m g ; m g > 800 GeV for m q m g 5
msugra/cmssm in trouble? little hierarchy problem: how do super-tev scale SUSY parameters conspire to give m(z)~91.2 GeV? Impose using weak or high scale parameters? weak scale less model-dependent Scan over msugra with LHC constraints and m(h)=125+-2 GeV: EW (min) 100 1% or less EW F T HS (min) 1000 HB, Barger, Huang, Mickelson, Mustafayev, Tata 6
No sign of SUSY at LHC so far: should we be alarmed? To large extent, these results have been anticipated by many theorists Well-known result: gravity mediation suffers from SUSY flavor/cp problems- in fact, these were motivation to create alternative models (GMSB/AMSB:minimal versions now excluded) In gravity mediation, m(sparticle) m 3/2 ; if m 3/2 < 5 TeV and T R > 10 4 GeV then gravitinos overproduced; BBN constraints one solution solves all: decoupling Dine, Kagan, Samuel; Cohen, Kaplan, Nelson; Arkani-Hamed, Murayama; 1st/2nd generation scalars~10-50 TeV 7
But what of fine-tuning: SUSY and EW scale link? Minimization of SUSY scalar potential: All terms on RHS M 2 Z Then: Natural SUSY! m t 1,2, m b1 µ<150 200 GeV < 500 GeV m g < 500 GeV m q, 10 50 TeV 8
Natural SUSY:some history Chan, Chattapadyay, Nath: PRD58 (1998)096004 Feng, Matchev, Moroi, FP papers Kitano, Nomura: low mu scenario HB, Barger, Huang: only mu is small ``hidden SUSY Arkani-Hamed; Papucci et al; Brust et al. 2011 HB, Barger, Huang, Tata, 2012 Randall, Reece, 2012; etc... 9
Problem #1: very hard to generate m(h)=125 GeV Main reason: light top squarks Problem #2: thermally-produced neutralino relic density low by 10-15: reason: light higgsino-like WIMPs 10
Can we reconcile m(h)~125 which requires TeV-scale top squarks with low EWFT which seemingly requires sub-tev stops? One solution: introduce extra matter or extra singlets: NMSSM extra vector-like matter: ad hoc? extra singlets (NMSSM): may introduce destabilizing divergences: Ulwanger; Bagger&Poppitz; Bagger, Poppitz& Randall 11
Better solution: Radiative Natural SUSY FT measure EW Large A_t suppress rad.corr. from t1 while enhance m(h)! m 2 t 2 /Q 2 e suppresses F HB, Barger, Huang, Mustafayev, Tata, arxiv:1207.3343 (PRL-in press) 12
large stop mixing softens EWFT while raising m(h)! 13
Detailed scan over RNS p-space: Need low mu, large A0 HB, Barger, Huang, Mickelson, Mustafayev, Tata 14
Sparticle masses from RNS mu~100-300 GeV m(t1)~1-2 TeV m(t2)~2-5 TeV m(gl)~1-5 TeV m(z2)-m(z1)~10-50 GeV m(w1)<300-400 GeV 15
Sample benchmark points m(t1)~1.5 TeV m(t2)~3-5 TeV But RNS has lower EWFT than generic NS models and also m(h)~125 GeV! 16
Consequences for colliders squarks ~10 TeV but m(gluino)~1-5 TeV: reach of LHC8 to m(gl)~1.1 TeV; LHC14 to m(gl)~2 TeV for >100 fb^-1: maybe see at LHC but maybe not low mass OS dilepton pairs from Z2->Z1 e+ e- from gluino pair cascade decays: m(e+e-)<~10-20 GeV; Z2=higgsino-like higgsino-like chargino pairs accessible to ILC with s 0.3 1 TeV 17
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Mixed higgsino-axion CDM in radiative natural SUSY f a 10 14 GeV allowed! Abundance of higgsinos is boosted due to thermal production and decay of axinos in early universe: the axion saves the day for WIMP direct detection! Detection of relic axions also possible 20
Perspective in LHC8 era Discovery of h(125) at Atlas, CMS, CDF/D0 compelling and hints at SUSY; further searches are on the way in 2012 at LHC8! No sign of SUSY so far; this is to be expected in models where SUSY flavor/cp/pdecay/gravitino problem solved by decoupling Naturalness/m(h)~125 GeV reconciled within MSSM by Radiative Natural SUSY with light higgsinos, medium-light gluinos: hard to see at LHC but ILC is higgsino factory! Dark matter: preference from theory for axion-higgsino admixture: detect both? 21