28 research outputs found
A Window on the CP-violating Phases of MSSM from Lepton Flavor Violating Processes
It has recently been shown that by measuring the transverse polarization of
the final particles in the LFV processes , and
, one can derive information on the CP-violating phases of the
underlying theory. We derive formulas for the transverse polarization of the
final particles in terms of the couplings of the effective potential leading to
these processes. We then study the dependence of the polarizations of and
in the and on the parameters of the
Minimal Supersymmetric Standard Model (MSSM). We show that combining the
information on various observables in the and
search experiments with the information on the electric dipole moment of the
electron can help us to solve the degeneracies in parameter space and to
determine the values of certain phases.Comment: 16 pages, 8 figure
Electron Electric Dipole Moment from Lepton Flavor Violation
The general Minimal Supersymmetric Standard Model introduces new sources for
Lepton Flavor Violation (LFV) as well as CP-violation. In this paper, we show
that when both sources are present, the electric dipole moment of the electron,
, receives a contribution from the phase of the trilinear -term of
staus, . For , the value of ,
depending on the ratios of the LFV mass elements, can range between zero and
three orders of magnitude above the present bound. We show that the present
bound on rules out a large portion of the CP-violating and the LFV
parameter space which is consistent with the bounds on the LFV rare decays.
We show that studying the correlation between and the P-odd asymmetry
in helps us to derive a more conclusive bound on
We also discuss the possibility of cancelation among the contributions of
different CP-violating phases to .Comment: 35 pages, 9 figure
Constraints on Randall-Sundrum model from top-antitop production at the LHC
We study the top pair production cross section at the LHC in the context of
Randall-Sundrum model including the Kaluza-Klein (KK) excited gravitons. It is
shown that the recent measurement of the cross section of this process at the
LHC restricts the parameter space in Randall-Sundrum (RS) model considerably.
We show that the coupling parameter () is excluded by
this measurement from 0.03 to 0.22 depending on the mass of first KK excited
graviton (). We also study the effect of KK excitations on the spin
correlation of the top pairs. It is shown that the spin asymmetry in
events is sensitive to the RS model parameters with a reasonable choice of
model parameters.Comment: 17 pages, 6 figure
Top pair Asymmetries at Hadron colliders with general couplings
Recently it has been shown that measurement of charge asymmetry of top pair
production at LHC excludes any flavor violating vector gauge boson that
could explain Tevatron forward-backward asymmetry (FBA). We consider the
general form of a gauge boson including left-handed, right-handed vector
and tensor couplings to examine FBA and charge asymmetry. To evaluate top pair
asymmetries at Tevatron and LHC, we consider mixing constraints on
flavor changing couplings and show that this model still explain
forward-backward asymmetry at Tevatron and charge asymmetry can not exclude it
in part of parameters space.Comment: 18 pages, 7 figure
The Impact of Kaluza-Klein Excited W Boson on the Single Top at LHC and Comparison with other Models
We study the s-channel single top quark production at the LHC in the context
of extra dimension theories, including the Kaluza-Klein (KK) decomposition. It
is shown that the presence of the first KK excitation of gauge boson can
reduce the total cross section of s-channel single top production considerably
if () for () in
proton-proton collisions. Then the results will be compared with the impacts of
other beyond Standard Model (SM) theories on the cross section of single top
s-channel. The possibility of distinguishing different models via their effects
on the production cross section of the s-channel is discussed.Comment: 23 pages,6 figure
CP violation in sbottom decays
We study CP asymmetries in two-body decays of bottom squarks into charginos
and tops. These asymmetries probe the SUSY CP phases of the sbottom and the
chargino sector in the Minimal Supersymmetric Standard Model. We identify the
MSSM parameter space where the CP asymmetries are sizeable, and analyze the
feasibility of their observation at the LHC. As a result, potentially
detectable CP asymmetries in sbottom decays are found, which motivates further
detailed experimental studies for probing the SUSY CP phases.Comment: 29 pages, 7 figure