Bhaskar Dutta
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Transcript of Bhaskar Dutta
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Bhaskar Dutta
Texas A&M University
Dark Matter and neutrinos
Allahverdi, Campbell, Dutta, Phys.Rev. D85 (2012) 035004Allahverdi, Bornhauser, Dutta, Richardson-McDaniel Phys.Rev. D80 (2009) 055026Allahverdi, Dutta, Richardson-McDaniel, Santoso, Phys.Lett. B677 (2009) 172
MSSM x U(1)B-L
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Only left-handed neutrinos have charges under SM
Under MSSM x U(1)B-L :
The new sneutrino: (inside ) can be a dark matter candidate of this model
N~
Non-zero neutrino masses are well accommodated in U(1)B-L
We have a new gauge boson: +SUSY partner'Z
W = WMSSM + l NcHuL + )(HH '2
'2
'1
ccNNfHLc contains ec and Nc Nc: Right Handed Neutrino
Fields: Q Qc L Lc QB-L : 1/6 -1/6 -1/2 1/2 1 -1
+ SUSY partners'2H
'1H
cL~
R. Allahverdi, B. Dutta,K. Richardson-Mcdaniel, Y. Santoso
Phys.Rev.D79:075005,2009
cNH ,' are MSSM singlets
MSSM x U(1)B-L and Unification
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The gauge couplings unify => gB-L (TeV) ~ 0.4: Low scale breakingWe use the spectrum (from the previous page) :
MSSM x U(1)B-L can be unified in SO(10) GUT Dutta, Mimura, Mohapatra; Phys.Rev. D87 (2013) 075008
The unificationholds with QB-L for Higgs=3/2, -3/2 or(1, -1)
Phys.Lett.B677:172,2009
R. Allahverdi, B. Dutta,K. Richardson-Mcdaniel, Y. Santoso
The B-L symmetry is broken: between EW scale to GUT scale
MSSM x U(1)B-L and Dark Matter
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Sneutrino annihilate into new Higgs/fermions
ff
NN
*
cc
*
N~N~ N~N~
N~N~ S-channel Z’, Higgs’
T channel Z’-ino
S-channel Z’, Higgs’
F, A: Heavy Higgs final states are also there, but are mostly kinematically suppressed
The annihilation cross-sections involving Higgs are governed by the D terms interactions involving MZ’
MSSM x U(1)B-L and ICECUBE
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Case1: Sneutrinos annihilate to produce mostly taus, b’sAll these final states produce neutrinosIceCube
m neutrino flux from Sun m rates detection
taus, b’s produce left handed neutrino in 3 body decay processes
From Sun
MSSM x U(1)B-L and ICECUBE
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Case 2: Sneutrinos annihilate to produce mostly Right-handed neutrinos which then decay into left handed neutrinos via Dirac coupling
mSUGRA: Hyperbolic branch/Focus point. Best case for mSUGRA at the IceCube
R. Allahverdi, S. Bornhauser, B. Dutta, K. Richardson-Mcdaniel
From Sun
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Annihilation to Neutrinos
All-sky event rates for 150 GeV sneutrino DM scatters into 135 GeV RH neutrinos each of which decays to a light neutrino and SM Higgs
All-sky event rates for 150 GeV Neutralino DMtt (blue), WW (blue), bb (red)
Allahverdi, Campbell, Dutta
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Majorana vs DiracCan we see the difference between Majorana – Dirac type neutrino?
Light Neutrino mass: 1) l nL <v> : Dirac type (l is very small) 2) : Majorana type (l is large, MR is 1 TeV or larger)
LHC? Any signal ? Indirect Detection? Any Signal
Also Neutrino mixing matrix introduces PMNS matrix flavor violation in the slepton sector: LHC signal? LFV In the context of mSUGRA: Allahverdi, Dutta, Kamon Krislock Phys.Rev. D86 (2012) 015026
TDR
D MMM )(1nn
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Majorana vs Dirac
cc N~N~ NN
Dirac Case: Nc does not decay due to small l, DNeff > 0, current Planck: 0:48+0.48-0.45
Majorana case: Nc decays into n + Higgs
Higgs decays into bs, t’s: Photon signal (Fermi) and neutrino signal (IceCube)
Indirect Detection
Allahverdi, Campbell, Dutta, Gao, In preparation
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Conclusion
Neutrino mass differences and mixing angles are well measured
Models which explain neutrino masses require new symmetry
These models can have new DM candidate, e.g., spin 0 sneutrino
The origin of neutrino mass can be distinguished indirect detection
The Lepton flavor violation arising in this model can be investigated at the LHC