Dark Matter Phenomenology of the GUT-less CMSSM Pearl Sandick University of Minnesota Ellis, Olive & PS, Phys. Lett. B 642 (2006) 389 Ellis, Olive & PS, JHEP 06 (2007) 079
Why we like SUSY Solves the Naturalness Problem Gauge coupling unification (GUTs) Predicts a light Higgs boson R-Parity conservation Dark Matter Candidate! Pearl Sandick, UMN
Parameter Soup Don’t observe boson-fermion degeneracy, so SUSY must be broken (How?) Most general case (MSSM) has > 100 new parameters! Make some assumptions about SUSY breaking at a high scale, and evolve mass parameters down to low scale for observables Explicitly add [soft] SUSY-breaking terms to the theory Masses for all gauginos and scalars Couplings for scalar-scalar and scalar-scalar-scalar interactions Virtues of CMSSM: easy to calculate! Generic features can be understood… CMSSM (similar to mSUGRA) Assume universality of soft SUSY-breaking parameters at MGUT Free Parameters: m0, m1/2, A0, tan(), sign() Pearl Sandick, UMN
SUSY Dark Matter 1. Assume neutralinos were once in thermal equilibrium 2. Solve the Boltzmann rate equation to find abundance now Pearl Sandick, UMN
Be Careful! Situations when care must be taken to properly calculate (approximate) the relic density: 1. s - channel poles 2 m mA 2. Coannihilations m mother sparticle 3. Thresholds 2 m final state mass Griest and Seckel (1991) Pearl Sandick, UMN
Constraints Apply constraints from colliders and cosmology: mh > 114 GeV m± > 104 GeV BR(b s ) HFAG BR(Bs +--) CDF (g -- 2)/2 g-2 collab. LEP 0.09 h2 0.12 Pearl Sandick, UMN
CMSSM Focus Point Coannihilation Strip LEP Higgs mass Relaxed LEP Higgs LEP chargino mass g--2 suggested region 2 < 0 (no EWSB) stau LSP Coannihilation Strip Pearl Sandick, UMN
Rapid annihilation funnel 2m mA CMSSM Rapid annihilation funnel 2m mA bs B+-- Pearl Sandick, UMN
tan() CMSSM >0 and A0=0 0.094 < h2 < 0.129 35,40,45,50,55 Shaded region is compatible with g-2 at 2 sigma Note: focus point region not shown Pearl Sandick, UMN
CMSSM Summary (If DM consists mainly of neutralinos), the constraint on the relic density of neutralinos restricts m1/2 and m0 to thin strips of parameter space. tan() provides leverage. Most of parameter space is not compatible with measured DM density. Pearl Sandick, UMN
Scale of universality of the soft breaking parameters: Min GUT-less CMSSM What if SUSY breaking appears below the GUT scale? Should the soft breaking parameters be universal below the SUSY GUT scale? Mixed modulus-anomaly mediated SUSY breaking with KKLT type moduli stabilization (mirage mediation models), warped extra dimensions, … SUSY broken in a hidden sector (communication to observable sector?) Add one new parameter! Scale of universality of the soft breaking parameters: Min Pearl Sandick, UMN
Evolution of the Soft Mass Parameters M1/2 = 800 GeV First look at gaugino and scalar mass evolution. Gauginos (1-Loop): Results shown later use full 2-loop expressions. a = 1,2,3 (bino, wino, gluino) Running of gauge couplings identical to CMSSM case, so low scale gaugino masses are all closer to m1/2 as Min is lowered. Pearl Sandick, UMN
Evolution of the Soft Mass Parameters m0 = 1000 GeV First look at gaugino and scalar mass evolution. Scalars (1-Loop): …reduced energy range over which running occurs for soft breaking parameters, so they end up more similar to their input (high) scale values as M_in is lowered. As Min low scale Q, expect low scale scalar masses to be closer to m0. Pearl Sandick, UMN
Evolution of the Soft Mass Parameters Higgs mass parameter, (tree level): M1 an m2 are the soft Higgs masses associated with H1 and H2. For fixed m_1/2, mu^2 becomes negative (unphysical) at lower m_0. As Min low scale Q, expect low scale scalar masses to be closer to m0. 2 becomes generically smaller as Min is lowered. Pearl Sandick, UMN
Mass Evolution with Min m1/2 = 800 GeV m0= 1000 GeV A0 = 0 tan() = 10 > 0 Pearl Sandick, UMN
Neutralinos and Charginos Must properly include coannihilations involving all three lightest neutralinos! m1/2 = 800 GeV m0= 1000 GeV A0 = 0 tan() = 10 > 0 Pearl Sandick, UMN
Lowering Min h2 too small! Pearl Sandick, UMN
Lowering Min – large tan() h2 too small! Pearl Sandick, UMN
Direct Detection Plot all cross sections not forbidden by constraints If neutralinos are DM, they are present locally, so will occasionally bump into a nucleus. Effective 4-fermion lagrangian for neutralino-nucleon scattering (velocity-independent pieces): Plot all cross sections not forbidden by constraints If calc < CDMWMAP, scale by calc/CDMWMAP Assume pi-nucleon Sigma term is 64 MeV spin independent (scalar) spin dependent Fraction of nucleus participates Important for capture & annihilation rates in the sun Whole nucleus participates Best prospects for direct detection Pearl Sandick, UMN
Neutralino-Nucleon Scattering tan = 10, Min = MGUT Green is fail relaxed Higgs constraint (but pass chargino mass) 4 curves are current CDMS II and XENON10 limits, and projected SuperCDMS at Soudan and projected XENON100 sensitivities Pearl Sandick, UMN
Neutralino-Nucleon Scattering tan = 10, Min = 1012 GeV Pearl Sandick, UMN
Summary/Conclusions Relaxed the standard CMSSM assumption of universality of soft breaking parameters at the GUT scale Examined the impact of lower Min on the constraints from colliders and cosmology Specific attention to consequences for neutralino dark matter In GUT-less CMSSM, constraint on dark matter abundance changes dramatically with Min Below critical Min, neutralinos can not account for the measured relic density! Pearl Sandick, UMN
EXTRA SLIDES Pearl Sandick, UMN
Non-zero Trilinear Couplings A0 > 0 larger weak-scale trilinear couplings, Ai Large loop corrections to depend on Ai, so is generically larger over the plane than when A0 = 0. Also see stop-LSP excluded region Pearl Sandick, UMN
Neutralino-Nucleon Scattering tan = 50, Min = MGUT Green is fail relaxed Higgs constraint (but pass chargino mass) Xenon10 is 3 *10^-8 at about 30 GeV Pearl Sandick, UMN
Neutralino-Nucleon Scattering tan = 50, Min = 1014 GeV Pearl Sandick, UMN