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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. Dark Matter Candidate!. R-Parity conservation. Why we like SUSY. Solves the Naturalness Problem
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Dark Matter Phenomenologyof 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
Dark Matter Candidate! R-Parity conservation Why we like SUSY • Solves the Naturalness Problem • Gauge coupling unification (GUTs) • Predicts a light Higgs boson 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 • 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 collidersandcosmology: 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
Focus Point LEP Higgs mass Relaxed LEP Higgs LEP chargino mass 2 < 0 (no EWSB) g--2 suggested region stau LSP Coannihilation Strip CMSSM Pearl Sandick, UMN
Rapid annihilation funnel 2m mA bs B+-- CMSSM Pearl Sandick, UMN
tan() CMSSM >0 and A0=0 0.094 < h2 < 0.129 tan() = 5,10,15,20,25,30, 35,40,45,50,55 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
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
M1/2 = 800 GeV Evolution of the Soft Mass Parameters • First look at gaugino and scalar mass evolution. • Gauginos (1-Loop): • 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
m0 = 1000 GeV Evolution of the Soft Mass Parameters • First look at gaugino and scalar mass evolution. • Scalars (1-Loop): • 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): • 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
h2 too small! Lowering Min Pearl Sandick, UMN
h2 too small! Lowering Min – large tan() Pearl Sandick, UMN
Direct Detection If neutralinos are DM, they are present locally, so will occasionally bump into a nucleus. • Plot all cross sections not forbidden by constraints • If calc < CDMWMAP, scale by calc/CDMWMAP Effective 4-fermion lagrangian for neutralino-nucleon scattering (velocity-independent pieces): 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 Pearl Sandick, UMN
Neutralino-Nucleon Scattering tan = 10, Min = 1012GeV 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 Pearl Sandick, UMN
Neutralino-Nucleon Scattering tan = 50, Min = 1014GeV Pearl Sandick, UMN