Tools for Supersymmetric Phenomenology by Ben Allanach (University - PowerPoint PPT Presentation

Tools for Supersymmetric Phenomenology by Ben Allanach (University of Cambridge) Talk outline • SPA project http://spa.desy.de/spa/ , http://www.ippp.dur.ac.uk/montecarlo/BSM/ • Bestiary of public codes only: supposedly impartial • Predictions for the LHC: partial Tools for Supersymmetric Phenomenology: YETI 2008 B.C. Allanach – p.1/34

MSSM Tools Theory BC Dark matter SUSY Spectrum calculator Input observables: MZ, mt, Indirect observables Decays EW/flavour etc Event generator Detector simulation SLHA: Skands et al , JHEP 0407 (2004) 036 , SLHA2 on here (NMSSM, RPV, FV, CPV), arXiv:0801.0045 Tools for Supersymmetric Phenomenology: YETI 2008 B.C. Allanach – p.2/34

Spectrum and decays • ISASUSY decouples particles at the mass thresholds but misses some finite terms in the matching: re-sums log splittings. • SOFTSUSY , sPHENO , SUSPECT all catch the finite terms but do the splittings to leading log in RPC-MSSM. • CPsuperH , FeynHiggs do Higgs mass spectrum and decays with of CP violating MSSM • NMSPEC does the CNMSSM spectrum, NMHDECAY gives the decays widths etc • PYTHIA , ISASUSY , sPHENO and SusyHIT do decays of Higgs and SUSY particles in MSSM. Tools for Supersymmetric Phenomenology: YETI 2008 B.C. Allanach – p.3/34

Web Page http://kraml.home.cern.ch/kraml/comparison/ BCA, S Kraml in hep-ph/0402295 Tools for Supersymmetric Phenomenology: YETI 2008 B.C. Allanach – p.4/34

Matrix Element Generators • Feyn Arts/Feyn Calc • Additional hard jets cannot be modelled reliably using the parton shower - you need to simulate the matrix element. • SMADGRAPH , compHEP , calcHEP , GRACE do SUSY and more general models at tree level. 2 to 4 possible. BRIDGE can be used to remember spin information in the decays. • WHIZARD , SUSYGEN - polarisation included for e + e − • PROSPINO does NLO-QCD sparticle production q ˜ q ˜ Tools for Supersymmetric Phenomenology: YETI 2008 B.C. Allanach – p.5/34

Event Generation • Can pass matrix-element generated events to event generators with the (original) Les Houches Accord • PYTHIA used extensively. Includes RPV. phase-space decays. ISAJET too. • HERWIG maintains spin info down cascade decays. RPV too. • SHERPA matches up ME with more standard event generation. • Shift toward C++ Tools for Supersymmetric Phenomenology: YETI 2008 B.C. Allanach – p.6/34

SUSY Prediction of Ω h 2 • Assume relic in thermal equilibrium with n eq ∝ ( MT ) 3 / 2 exp ( − M/T ) . • Freeze-out with T f ∼ M f / 25 once interaction rate < expansion rate ( t eq critical) • microMEGAs uses calcHEP to automatically calculate relevant Feynman diagrams for some given model Lagrangian: flexible . susyBSG • darkSUSY , ISATOOLS has MSSM annihilation channels hard-coded. Much work on (in)- direct detection possibilities. Tools for Supersymmetric Phenomenology: YETI 2008 B.C. Allanach – p.7/34

Constraints on SUSY Models CMSSM well-studied in literature: eg Ellis, Olive et al PLB565 (2003) 176; Roszkowski et al JHEP 0108 (2001) 024; Baltz, Gondolo, JHEP 0410 (2004) 052;... tan β = 10 , µ > 0 800 800 m h = 114 GeV 700 700 600 600 m 0 (GeV) m χ± = 104 GeV 500 500 400 400 300 300 200 200 100 100 0 0 100 100 200 200 300 300 400 400 500 500 600 600 700 700 800 800 900 900 1000 1000 m 1/2 (GeV) Tools for Supersymmetric Phenomenology: YETI 2008 B.C. Allanach – p.8/34

b Observables CMSSM: Ellis, Heinemeyer, Olive, Weber, Weiglein, arXiv:0706.0652 BR ( B u → τν ) , ∆ M B s 14 1.4 12 1.2 BR(B u -> τ ν τ ): MSSM/SM 10 1.0 2 (today) 8 0.8 CMSSM, µ > 0, m t = 171.4 GeV tan β = 50, A 0 = 0 χ 6 0.6 CMSSM, µ > 0, m t = 171.4 GeV tan β = 50, A 0 = +m 1/2 tan β = 50, A 0 = 0 tan β = 50, A 0 = -m 1/2 4 0.4 tan β = 50, A 0 = +m 1/2 tan β = 50, A 0 = +2 m 1/2 tan β = 50, A 0 = -m 1/2 tan β = 50, A 0 = -2 m 1/2 2 0.2 tan β = 50, A 0 = +2 m 1/2 tan β = 50, A 0 = -2 m 1/2 0 0.0 0 200 400 600 800 1000 1200 1400 1600 1800 2000 200 400 600 800 1000 1200 1400 1600 1800 2000 m 1/2 [GeV] m 1/2 [GeV] Tools for Supersymmetric Phenomenology: YETI 2008 B.C. Allanach – p.9/34

Fit Development • Typically done 2d scans with 2 σ exclusion regions, but in general we have α ( M Z ) , α s ( M Z ) , m t , m b , m 0 , M 1 / 2 , A 0 , tan β to vary • Effective 3d type scan done a which parameterises a 2d surface of central Ω h 2 • 4d scan b used the impressive Markov Chain Monte Carlo technique like in cosmology. • Combine likelihoods from all of the different measurements. a Ellis et al , arXiv:0706.0652 b Baltz, Gondolo, JHEP 0410 (2004) 052 Tools for Supersymmetric Phenomenology: YETI 2008 B.C. Allanach – p.10/34

Markov-Chain Monte Carlo Metropolis-Hastings Markov chain sampling consists of list of parameter points x ( t ) and associated posterior probabilities p ( t ) . x ( t +1) , p ( t +1) r p(r) σ P = min ( p ( t +1) /p ( t ) , 1) x ( t ) , p ( t ) r Final density of x points ∝ p . Required number of points relatively insensitive to number of dimensions. Tools for Supersymmetric Phenomenology: YETI 2008 B.C. Allanach – p.11/34

Implementation Input parameters are: m 0 , A 0 , M 1 / 2 , tan β , • m t = 171 . 4 ± 2 . 9 , m b ( m b ) = 4 . 24 ± 0 . 11 GeV, • α s ( M Z ) MS = 0 . 1176 ± 0 . 002 , α − 1 ( M Z ) MS = 127 . 918 ± 0 . 018 For the likelihood, we also use • Ω DM h 2 = 0 . 104 +0 . 0073 − 0 . 0128 micrOMEGAs • δ ( g − 2) µ / 2 = (22 ± 10) × 10 − 10 Stöckinger et al • BR [ b → sγ ] = (3 . 55 ± 0 . 38) × 10 − 4 susyBSG • sin 2 θ l w ( eff ) = 0 . 23153 ± 0 . 000175 • M W = 80 . 392 ± 0 . 031 GeV W Hollik, A Weber et al Tools for Supersymmetric Phenomenology: YETI 2008 B.C. Allanach – p.12/34

Killer Inference for Susy METeorology BCA, Cranmer, Weber, Lester, arXiv:0705.0487 P/P(max) P/P(max) 4 4 1 1 0.9 3.5 3.5 0.8 0.8 3 3 0.7 m 0 (TeV) 2.5 m 0 (TeV) 2.5 0.6 0.6 2 2 0.5 1.5 1.5 0.4 0.4 1 1 0.3 0.5 0.5 0.2 0.2 0 0 0.1 0 0.5 1 1.5 2 0 0.5 1 1.5 2 0 0 M 1/2 (TeV) M 1/2 (TeV) http://users.hepforge.org/ ˜ allanach/benchmarks/kismet.html strong 1.2 (L/Lmax) 4 1 weak gaugino slepton Frequentist 0.9 3.5 1 0.8 3 L/L(max) 0.8 0.7 m 0 (TeV) 2.5 0.6 2 0.6 0.5 1.5 0.4 0.4 1 0.3 0.5 0.2 0.2 0 0.1 0 0 0.5 1 1.5 2 0 -6 -4 -2 0 2 4 6 M 1/2 (TeV) Tools for Supersymmetric Phenomenology: YETI 2008 B.C. Allanach – p.13/34 log 10 σ /fb

Killer Inference for Susy METeorology BCA, Cranmer, Weber, Lester, arXiv:0705.0487 Bayesian 1 Bayesian 2 http://users.hepforge.org/ ˜ allanach/benchmarks/kismet.html strong 1.2 (L/Lmax) 4 1 weak gaugino slepton Frequentist 0.9 3.5 1 0.8 3 L/L(max) 0.8 0.7 m 0 (TeV) 2.5 0.6 2 0.6 0.5 1.5 0.4 0.4 1 0.3 0.5 0.2 0.2 0 0.1 0 0 0.5 1 1.5 2 0 -6 -4 -2 0 2 4 6 M 1/2 (TeV) Tools for Supersymmetric Phenomenology: YETI 2008 B.C. Allanach – p.13/34 log 10 σ /fb

Higgs Meteorology BCA, Cranmer, Lester, Weber arXiv:0705:0487 4 4 0.08 w=1 w=2 3.5 3.5 0.07 profile 0.06 3 3 Buchmuller et al , arXiv:0707:3447 0.05 2.5 2.5 0.04 P 2 2 0.03 1.5 1.5 0.02 1 1 0.01 0.5 0.5 LEP Theoretically 0 excluded inaccessible 110 115 120 125 130 135 0 0 90 90 100 100 110 110 120 120 130 130 140 140 m h /GeV Figure 0: Including (LHS) or not including (RHS) the LEP2 direct Higgs mass constraints on the CMSSM. Tools for Supersymmetric Phenomenology: YETI 2008 B.C. Allanach – p.14/34

Other literature Roszkowski, Ruiz & Trotta (2007) Roszkowski, Ruiz & Trotta (2007) −4 4 CMSSM, µ > 0 3.5 −5 ZEPLIN−I EDELWEISS−I 3 −6 CDMS−II SI (pb)] 2.5 m 0 (TeV) −7 2 Log[ σ p −8 1.5 −9 1 −10 0.5 CMSSM µ >0 −11 0.2 0.4 0.6 0.8 1 0.5 1 1.5 2 m 1/2 (TeV) m χ (TeV) R. R. de Austri, R. Trotta and L. Roszkowski, arXiv:0705.2012 , including some NNLO b → sγ pieces. susyBayes Tools for Supersymmetric Phenomenology: YETI 2008 B.C. Allanach – p.15/34

Fitting to SUSY Breaking Model m 1 / 2 [GeV] 2.4 480 Spheno 460 Spheno Suspect tan β 2.2 Isajet 440 Isajet 2. 420 Softsusy 1.8 400 Softsusy Suspect 380 1.6 360 200 300 400 500 600 200 300 400 500 600 m 0 [GeV] m 0 [GeV] • Experimenters pick a SUSY breaking point • They derive observables and errors after detector simulation • We fit this “data” with our codes BCA, S Kraml, W Porod, JHEP 0303 (2003) 016 Tools for Supersymmetric Phenomenology: YETI 2008 B.C. Allanach – p.16/34

Fits to future collider data Mass (GeV) 1000 Mass (GeV) 1000 Mass (GeV) 270 900 900 265 260 800 800 255 ~ L e 250 700 700 245 L L ~ ~ e e 240 600 600 235 230 500 500 225 220 400 400 115 120 125 130 135 140 145 ∼ χ 0 Mass (GeV) 1 300 300 σ ( � P T ) 200 200 100 100 0 0 0 100 200 300 400 500 600 700 800 9001000 0 100 200 300 400 500 600 700 800 9001000 ∼ ∼ χ χ 0 0 Mass (GeV) Mass (GeV) 1 1 Lester, Parker, White, JHEP 0601 (2006) 080 • Assume edge measurements from some SUSY point: what constraints exist on the phenomenological MSSM? • SFITTER / FITTINO Tools for Supersymmetric Phenomenology: YETI 2008 B.C. Allanach – p.17/34