mesino oscillations AKSHAY GHALSASI, DAVE MCKEEN, ANN NELSON - - PowerPoint PPT Presentation
Baryogenesis via mesino oscillations AKSHAY GHALSASI, DAVE MCKEEN, ANN NELSON arxiv:1508.05392 The one minute summary 2 Mesino a bound state of colored scalar and quark Model analogous to Kaon system Mesinos form after the QCD
AKSHAY GHALSASI, DAVE MCKEEN, ANN NELSON arxiv:1508.05392
Mesino a bound state of colored scalar and quark Model analogous to Kaon system Mesinos form after the QCD hadronization temp Oscillations analogous to Kaon system give CP
violation
Baryon violating decays give baryogenesis
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Introduction and Motivation The Model Oscillations and CP Asymmetry Experimental Constraints Cosmology Conclusion
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Universe is made up of baryons
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Sakharov conditions
Models of baryogenesis require high reheating
temperature
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No evidence of high reheating temperature Many reasonable theories favor a low reheating scale
There do exist low scale baryogenesis models(Claudson et al
’84, Dimopolous et al ‘87)
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N2,3 N1
O(TeV)
colored scalars singlet fermions majorana mass
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Oscillations and CP violation B violation real and diagonal two complex phases remain all 9 phases remain
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s
di uj N1 di
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s*
di* u*j Baryon +mesons Antibaryon +mesons
s
N1 +mesons N1 di*
s*
N1 +mesons
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Off shell diagrams On shell diagrams via common final states
N2 s N1 s*
O(TeV)
N2 N1
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s s*
Off shell oscillations 𝑁12:
Berger et al ‘13 s N1,2 s* Form factor N1 N2
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Contributions to Γ
12:
We want to be in the squeezed limit In squeezed limit one can show
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s s*
Hamiltonian without oscillations
With oscillations we get off diagonal terms 16
Hamiltonian has off diagonal terms, new eigenstates are Assuming a state starts as
at t = 0 then
CP violation gives
favoring one state over another
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Can show asymmetry per mesino-antimesino pair is given by Lets define
and then we have
We expect generally Can show
branching ratio into baryons
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q di uj q N1 di 2 jets soft quark, no jet soft quarks, no jet N1 dk di uj usually soft quark, no jet 2 jets
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Constraints from squarks decaying into b and
light quark: (CMS)
Effective constraints from squark decaying to
light quarks: (CMS)
Constraints from 3 jet events: We take
as our benchmark value
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upper bounds from Kaon
𝑜 oscillations and diinucleon decays, lower bounds from displaced vertices upper bound from cosmology upper bounds from 𝑜ത 𝑜 oscillations and dinucleon decays
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Totally fine set of couplings for
:
Constraints only get weaker with increasing mass
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T = 200 MeV N s s*
CP Violation
T
N3
Baryons
N3 N3 N3
Anti Baryons T = 1 MeV
Number density of N3 at hadronization temp Tc For N3 to last until Tc we need Small Yukawa imply N3 annihilations are slower than
expansion rate.
So most of the N3 survives till Tc
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We can coevolve the
radiation, N3 and baryons produced from their decay to get the exact solution
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Baryon to entropy ratio in sudden decay approximation Ratio of matter and radiation energy densities for ent. dil. However
and so 28
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Finding colored scalars at LHC (1 TeV at 1000 fb-1)
Any signature needs to be consistent with neutron-antineutron
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If there is a scalar quark it can form mesinos CP violation in mesino oscillations can be the
source for baryogenesis
In order to get enough CP violation we need the
singlets to be very close in mass with mesinos 32
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Displaced vertices search give us 𝑑τ < 1 𝑛𝑛 Φ → quarks : Φ → N1 → quarks: These constraints don’t apply if Mass independent constraints from BBN are 𝑃 106
weaker
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∆B = 2, neutron-antineutron oscillation:
For we get
Dinucleon to Kaon decay constraints for Easily satisfied if
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Constraints from KL and KS mass difference Constraints from CP violation in Kaon system B meson oscillations aren’t as constraining
s Ni d* Nj s* d
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