constrained mssm
Post on 15-Jan-2016
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Constrained MSSM
• Unification of the gauge couplings• Radiative EW Symmetry Breaking• Heavy quark and lepton masses• Rare decays (b -> sγ, b->μμ) • Anomalous magnetic moment of muon• LSP is neutral • Amount of the Dark Matter• Experimental limits from direct search
• Unification of the gauge couplings• Radiative EW Symmetry Breaking• Heavy quark and lepton masses• Rare decays (b -> sγ, b->μμ) • Anomalous magnetic moment of muon• LSP is neutral • Amount of the Dark Matter• Experimental limits from direct search
Requirements:
Allowed regionin the parameterspace of the MSSM
0 0 1/ 2, , , , tanA m M 0 0 1/ 2, , , , tanA m M
0 1/ 2100 GeV , , 2 TeVm M
0 0 03 3 , 1 tan 70m A m
Radiative EW Symmetry Breaking
1 2
2 2 222
2
tan
2 tan 1H HZ
m mM
2tan For given
0 1/ 2 and m m
1 1 0 1 TeVH Hm m m 1 TeV
Soft SUSY parameters Hard SUSY parameterμ - problem
Constrained MSSM ( (Choice of constraints)Experimental lower limits on Higgs and superparticle masses
tan β =35 tan β =50
114.3 GeVHiggsm Regions excluded by Higgs experimental limits provided by LEP2
B->s γ decay rate
Standard ModelStandard Model MSSMMSSM
~ ~ ~ ~
~ ~
~
~
~ ~~
H
W±, H±~ ~
4( ) (3.43 0.36) 10sB B X
SM:
MSSM
Experiment
Constrained MSSM (Choice of constraints)Data on rare processes branching ratios
tan β =35 tan β =50
4( ) (3.43 0.36) 10sB B X
Regions excluded by experimental limits (for large tanβ)
Rare Decay Bs → μ+ μ-
SM: Br=3.5٠10-9
2
~
Ex: <4.5٠ 10-8
Main SYSY contribution
SM
Constrained MSSM (Choice of constraints)Data on rare processes branching ratios
tan β =35 tan β =50
7( ) 3.7 10B Bs Regions excluded by experimental limits (for large tanβ)
211 2
2 2
( ) 4 100 GeV| | (1 ) 140 10 ( )
8SUSY SUSYZ
W SUSY SUSY
m MMa tan log tan
Sin M m M
Anomalous magnetic moment
EW
27±10
Constrained MSSM (Choice of constraints)Muon anomalous magnetic moment
Regions excluded by muon amm constraint
exp 10(27 10) 10tha a a
tan β =35 tan β =50
Constrained MSSM (Choice of constraints)
This constraint is a consequence of R-parity conservation requirement
The lightest supersymmetric particle (LSP) is neutral.
Regions excluded by LSP constraint
tan β =35 tan β =50
Favoured regions of parameter space
From the Higgs searches tan β >4, from aμ measurements μ >0
Pre-WMAP allowed regions in the parameter space.
tan β =35 tan β =50
In allowed region one fulfills all the constraints simultaneously and has the suitable amount of the dark matter
In allowed region one fulfills all the constraints simultaneously and has the suitable amount of the dark matter
Narrow allowed region enables one to predict the particle spectra and the main decay patterns
Narrow allowed region enables one to predict the particle spectra and the main decay patterns
Allowed regions after WMAP
WMAPLSPcharged
Higgs EWSB
tan β =50
Phenomenology essentially depends on the region of parameter space and has direct influence on the strategy of SUSY searches
Phenomenology essentially depends on the region of parameter space and has direct influence on the strategy of SUSY searches
SUSY Masses in MSSM
Gauginos+Higgsinos Squarks and Sleptons
Mass Spectrum in CMSSM
Symbol Low tan High tan
214, 413 64, 113
1028, 1016 194, 229
413, 1026 110, 130
1155 516
303, 270 1497, 1499
290 1495
1028, 936 1519, 1523
279, 403 1305, 1288
953, 1010 1309, 1152
727, 1017 906, 1046
h, H 95, 1344 115, 372
A, H 1340, 1344 372, 383
SUSY Masses in GeV
Fitted SUSY Parameters
Symbol Low tan High tan
tan 1.71 52.2
m 0 200 1500
m 1/2 500 170
(0) 1084 558
A(0) 0 0
1/ GUT 24.8 24.8
M GUT 16
1.6 •10 16
1.6 •10
0 03 1 4 2( ), ( )H H
0 0 31 2( ), ( )B W
1 2( ), ( )W H
g,L Re e
L,L Rq q
1 2,
1 2,b b
1 2,t t
(Sample)
95 115
The Lightest Superparticle
• Gravity mediation 0
1LSP stable
property signature
jets/leptons E T
• Gauge mediation LSP G stable E T
0
1NLSPRl
0
1 , ,G hG ZG photons/jets E T
Rl G lepton E T
• Anomaly mediation
0
1LSPL
stable
stablelepton E T
• R-parity violation LSP is unstable SM particles
Rare decaysNeutrinoless double decay• Modern limit 40 GeVLSPM
SUSY Dark MatterNeutralino = SUSY candidate for the cold Dark MatterNeutralino = the Lightest Superparticle (LSP) = WIMP
0 0 01 21 2 3 4N N z N H N H
photino zino higgsino higgsino
exp 40 GeVM
40 400 GeVtheorM
• Superparticles are created in pairs• The lightest superparticle is stable
3( ) 2( 1)
1, 1
B L S
p p
R
R R
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