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MSSM in view of PAMELA and Fermi-LAT
Ts. Enkhbat2nd workshop on LHC physics, CYCU, Chungli
Based on: arXiv: 1002.3631B. Bajc, Ts. E, D. K. Ghosh , G. Senjanovic, Y. Zhang
Outline
• Introduction• Decaying gravitino as the MSSM dark matter– Simple case
• Pamela and Fermi-LAT vs MSSM• Phenomenological and cosmological implications• Conclusions
Introduction The MSSM* is the main extension of the SM Virtues of the MSSM Stabilize the Gauge hierarchy Unification of the gauge couplings Dark matter candidateIn addition can provide the light Neutrino masses and mixings through RPV Electroweak baryogenesis if stop is light or [Carena et al, 2008]
Affleck-Dine baryogenesis through flat directions [Affleck & Dine, 1985] Inflation along the same flat directions [Allahverdi, 2006]
*Here we define the MSSM as supersymmetrization of the SM + gravitinoThe last item is the topic of the present talk:The dark matter candidate in light of recent Sattillete experiments:
PAMELA & Fermi-LAT
Sattellite experiments
• Pamela: 1.5 to 100GeV antiproton &positron flux
PAMELA collaboration, arXiv: 0810.4995
Fermi-LAT
Measures electron spectrum from 7GeV to 1TeV
Fermi LAT collaboration, arXiv: 0905.0025, 1008.3999
Possible interpretations Astrophysical sources - Supernova remnants for Fermi LAT D. Grasso et al, 2009 [Fermi-LAT collaboration]
- Nearby pulsars e.g. D. Hooper et al, 2009; P. Blasi, 2009; S. Profumo, 2008
Dark Matter - Annihilating DM - Decaying DM• A viable mechanism must induce excess leptons not hadrons.• We address this question in general MSSM
MSSM & decaying gravitino DM
In its most general form, MSSM contains
Constraints : nucleon decay
A. Y. Smirnov & F. Vissani, 1996
: oscillation
S. Dimopoulos & L.J. Hall, 1996; I. Hinchliffe & T. Kaeding, 1993; F. Zwirner, 1983; K.S. Babu& R. Mohapatra, 2001
uccccc
R LHdduQLdLLeW ''''
2
1
2
1
2~27'''
30010
GeV
ml
2/1~
2~87''
1001001010
GeV
m
GeV
mq nn
Neutrino masses
~
22
2~
2
2~
2'
2~
2
2~
2 ~;
16
3;
16 m
g
m
mm
m
mmm
q
bLRq
l
LRl
(or )dominates : 2/1
2
2~
2/1~3
)100(1.0110
GeV
m
eV
m
TeV
mLRll
dominates : a seesaw mechanism with the gaugino playing the role of the right handed neutrinos.
~
'
The size of the neutrino masses
Large values for RPV couplings
: Neutralinos cannot be DM! sec)1(0~ OLSP
The only viable candidate for DM is the Gravitino!
Gravitino decays
• Relevant gravitino interactions in SUGRA
..242
1chF
iD
Maa
L
Pl
• Effective 2&3-body decay operators
..2
..2
'
296
2~
3
3
2~
2
2~
2
chLPLPeePLPLMm
chWPgBPg
WPg
Mm
mi
L
c
LRR
Pl
eff
body
RRR
Pl
LReff
body
��
e
hadrons
ZW
h
mm
mmm
mm
Mm
mm
22/3
2/3
2/3
,2/3
2/3
0
0
'
/'
,0
0
WZ
h
Mass ranges Gravitino decay modes
Photon & Neutrino mode
m
TeV
GeV
mGeV
M
m
m
m
Pl
1
510
32
13
2/350
2
3
2/3
Takayama & Yamaguchi, 2000
Monochromatic photons and neutrinos
• No such signal observed by Fermi-LAT
• If neutrino mass is dominated by sneutrino VEV
GeV50
2/3 10 or GeVm 52/3
This case cannot explain PAMELA or Fermi-LAT!
2 & 3-body decay rates
2
3
2/3
4~
22~
5
22
2 18432 Pl
LR
M
m
m
mgW
WZW
220
2 cos2
1
WM
mh
W 22
22/30
2 864
2
3
2/3
4~
4
2/3
3
2
3 18432 PlM
m
m
m
2&3-body diagrams• Neutrino channels
• Charged lepton channels
• Higgs channels
• Three-body decay channels
• Criteria to fit neutrino mass and PAMELA and/or Fermi-LAT
4
10/
1010
3.003.0
2
32
49
3
51
GeVGeV
eVmeV (ν mass)
(PAMELA/Fermi-LAT)
(leptophilic DM)
(perturbativity bound)
4/1
51
3
2/5
2/3
4/124
~
49
3
2/12/5
2/3~
10400410
101.0400600
GeVGeV
mTeVm
GeVeV
m
GeV
mTeVm v
3/1
49
3
2/33/124/12
2/32/3
101.0435.05.0
3
GeVeV
m
TeV
m
TeV
m v
• The lower and upper bound on the slepton mass
• The upper limit on the gravitino mass
•An optimal fit for Fermi-LAT }14,5.1,14.0{4
2
for eVmv }3.0,1.0,03.0{
this leaves narrow range for gravitino mass
Allowed region compatible with PAMELA
The dashed line is the perturbativity bound. Blue (red) region is excluded by the gravitino (neutrino) mass.
Allowed region for Fermi-LAT
The dashed line is the perturbativity bound
eVmGeVGeVm v 2.0),103.0sec(103.2,400 50
3
26
2/32/3
• The fit for PAMELA only
•The allowed region in the 2/3~ mm plane (for PAMELA)
eVmGeVTeVm v 03.0),104.1sec(105,3.3 50
3
25
2/32/3
The simultaneous fit for PAMELA positron excess and Fermi-LAT due to 3-body gravitino decay
• Fit for PAMELA
• The fit for Fermi-LAT
eVmGeVTeVm v 03.0),104.1sec(105,3.3 50
3
25
2/32/3
Phenomenological consequences• There is no LHC signatures if both PAMELA and Fermi-LAT are to be explained by gravitino decay:
• Phenomenologically interesting case is if gravitino is behind PAMELA only
Gaugino NLSP:
metersdGeV
m
m
mMg
m
mgv Pl
30,600
sec10
6
3072~
~
5
~7~
2/37
2/3
5~
22
4~
5~
3
2200
for GeVGeVm 50
32/3 103.0,400
Sizable amount decays inside detector.If charged wino is NLSP, leave highly ionized tracks.
Light slepton (with vanishing RPV coupling) as NLSP
2
~~3
~
2/3
7
2/3
~
2~
23
4~
2~
7~
55
24
1
1600sec10
1010
~
01
0
1
00
1
TeV
m
GeV
m
m
m
m
M
mm
mgv Pl
In this case the NLSP decays outside the detector
Light slepton with 7
2/3
5
132
1
400600106
8
GeV
m
GeV
mGeV
m NLSPNLSPNLSP
If charged Displaced vertex /ionizing track, dilepton+If sneutrino 2 charged lepton final states
E
1
Conclusions The MSSM even if taken as the theory of the neutrino masses it explain
PAMELA excess. The sleptons are heavy with masses in the range 500 to 10^6 TeV The gravitino mass can be as light as 300 GeV Phenomenologically there is no constraint on the squark masses The Fermi-LAT data can be explaind only if the gravitino is around 3TeV.
Perturbativity pushes the gravitino to lighter values. The decaying gravitino as the explanation of Fermi-LAT will kill any chance
of MSSM being in the LHC range