1,460 research outputs found
Supersymmetric CP Violation in in Minimal Supergravity Model
Direct CP asymmetries and the CP violating normal polarization of lepton in
inclusive decay B \to X_s l^+ l^- are investigated in minimal supergravity
model with CP violating phases. The contributions coming from exchanging
neutral Higgs bosons are included. It is shown that the direct CP violation in
branching ratio, A_{CP}^1, is of {\cal{O}}(10^{-3}) for l=e, \mu, \tau. The CP
violating normal polarization for l=\mu can reach 0.5 percent when tan\beta is
large (say, 36). For l=\tau and in the case of large \tan\beta, the direct CP
violation in backward-forward asymmetry, A_{CP}^2, can reach one percent, the
normal polarization of \tau can be as large as a few percent, and both are
sensitive to the two CP violating phases, \phi_\mu and \phi_{A_0}, and
consequently it could be possible to observe them (in particular, the normal
polarization of \tau) in the future B factories.Comment: 14 pages, latex, 5 figure
CP Violation from Dimensional Reduction: Examples in 4+1 Dimensions
We provide simple examples of the generation of complex mass terms and hence
CP violation through dimensional reduction.Comment: 6 pages, typos corrected, 1 reference adde
Higgs-mediated leptonic decays of B_s and B_d mesons as probes of supersymmetry
If tan(beta) is large, down-type quark mass matrices and Yukawa couplings
cannot be simultaneously diagonalized, and flavour violating couplings of the
neutral Higgs bosons are induced at the 1-loop level. These couplings lead to
Higgs-mediated contributions to the decays B_s -> mu+ mu- and B_d -> tau+ tau-,
at a level that might be of interest for the current Tevatron run, or possibly,
at B-factories. We evaluate the branching ratios for these decays within the
framework of minimal gravity-, gauge- and anomaly-mediated SUSY breaking
models, and also in SU(5) supergravity models with non-universal gaugino mass
parameters at the GUT scale. We find that the contribution from gluino loops,
which seems to have been left out in recent phenomenological analyses, is
significant. We explore how the branching fraction varies in these models,
emphasizing parameter regions consistent with other observations.Comment: Revised to accommodate minor changes in original text and update
reference
Explicit Formulas for Neumann Coefficients in the Plane-Wave Geometry
We obtain explicit formulas for the Neumann coefficients and associated
quantities that appear in the three-string vertex for type IIB string theory in
a plane-wave background, for any value of the mass parameter mu. The derivation
involves constructing the inverse of a certain infinite-dimensional matrix, in
terms of which the Neumann coefficients previously had been written only
implicitly. We derive asymptotic expansions for large mu and find unexpectedly
simple results, which are valid to all orders in 1/mu. Using BMN duality, these
give predictions for certain gauge theory quantities to all orders in the
modified 't Hooft coupling lambda'. A specific example is presented.Comment: 28 pages, 2 figures, v2: reference added, new comments and appendix,
typos fixed in eqs. (86) and (89
Exclusive semileptonic rare decays K,K^*) \ell^+ \ell^- in supersymmetric theories
The invariant mass spectrum, forward-backward asymmetry, and lepton
polarizations of the exclusive processes are analyzed under supersymmetric context. Special attention is paid to
the effects of neutral Higgs bosons (NHBs). Our analysis shows that the
branching ratio of the process \bkm can be quite largely modified by the
effects of neutral Higgs bosons and the forward-backward asymmetry would not
vanish. For the process \bksm, the lepton transverse polarization is quite
sensitive to the effects of NHBs, while the invariant mass spectrum,
forward-backward asymmetry, and lepton longitudinal polarization are not. For
both \bkt and \bkst, the effects of NHBs are quite significant. The partial
decay widths of these processes are also analyzed, and our analysis manifest
that even taking into account the theoretical uncertainties in calculating weak
form factors, the effects of NHBs could make SUSY shown up.Comment: Several references are added, typo are correcte
B_s --> mu+ mu- decay in the R-parity violating minimal supergravity
We study B_s --> mu+ mu- in the context of the R-parity violating minimal
supergravity in the high tan beta regime. We find that the lowest value of the
branching ratio can go well below the present LHCb sensitivity and hence B_s
--> mu+ mu- can even be invisible to the LHC. We also find that the present
upper bound on Br(B_s --> mu+ mu-) puts strong constraint on the minimal
supergravity parameter space. The constraints become more severe if the upper
bound is close to its standard model prediction.Comment: 18 pages, 10 figures; version to be published in European Physical
Journal
Three heavy jet events at hadron colliders as a sensitive probe of the Higgs sector
Assuming that a non-standard neutral Higgs with an enhanced Yukawa coupling
to a bottom quark is observed at future hadron experiments, we propose a method
for a better understanding of the Higgs sector. Our procedure is based on
"counting" the number of events with heavy jets (where "heavy" stands for a c
or b jet) versus b jets, in the final state of processes in which the Higgs is
produced in association with a single high p_T c or b jet. We show that an
observed signal of the type proposed, at either the Tevatron or the LHC, will
rule out the popular two Higgs doublet model of type II as well as its
supersymmetric version - the Minimal Supersymmetric Standard Model (MSSM), and
may provide new evidence in favor of some more exotic multi Higgs scenarios. As
an example, we show that in a version of a two Higgs doublet model which
naturally accounts for the large mass of the top quark, our signal can be
easily detected at the LHC within that framework. We also find that such a
signal may be observable at the upgraded Tevatron RunIII, if the neutral Higgs
in this model has a mass around 100 GeV and \tan\beta > 50 and if the
efficiency for distinguishing a c jet from a light jet will reach the level of
50%.Comment: Revtex, 11 pages, 4 figures embedded in the text. Main changes with
respect to Version 1: Numerical results re-calculated using the CTEQ5L pdf,
improved discussion on the experimental consequences, new references added.
Conclusions remain unchanged. As will appear in Phys. Rev.
Prospects for heavy supersymmetric charged Higgs boson searches at hadron colliders
We investigate the production of a heavy charged Higgs boson at hadron
colliders within the context of the MSSM. A detailed study is performed for all
important production modes and basic background processes for the
t\bar{t}b\bar{b} signature. In our analysis we include effects of initial and
final state showering, hadronization, and principal detector effects. For the
signal production rate we include the leading SUSY quantum effects at high
\tan\beta>~ mt/mb. Based on the obtained efficiencies for the signal and
background we estimate the discovery and exclusion mass limits of the charged
Higgs boson at high values of \tan\beta. At the upgraded Tevatron the discovery
of a heavy charged Higgs boson (MH^+ >~ 200 GeV) is impossible for the
tree-level cross-section values. However, if QCD and SUSY effects happen to
reinforce mutually, there are indeed regions of the MSSM parameter space which
could provide 3\sigma evidence and, at best, 5\sigma charged Higgs boson
discovery at the Tevatron for masses M_H^+<~ 300 GeV and M_H^+<~ 250 GeV,
respectively, even assuming squark and gluino masses in the (500-1000) GeV
range. On the other hand, at the LHC one can discover a H^+ as heavy as 1 TeV
at the canonical confidence level of 5\sigma; or else exclude its existence at
95% C.L. up to masses ~ 1.5 TeV. Again the presence of SUSY quantum effects can
be very important here as they may shift the LHC limits by a few hundred GeV.Comment: Latex2e, 44 pages, 15 figures, 6 tables, uses JHEP3.sty, axodraw.sty.
Comments added. Discussion on QCD factors clarified. Added discussion on
uncertainties. Change of presentation of Tables 4 and 5 and Fig.6. Results
and conclusions unchanged. Version accepted in JHE
Analysis of Various Polarization Asymmetries In The Inclusive Decay In The Fourth-Generation Standard Model
In this study a systematical analysis of various polarization asymmetries in
inclusive b \rar s \ell^+ \ell^- decay in the standard model (SM) with four
generation of quarks is carried out. We found that the various asymmetries are
sensitive to the new mixing and quark masses for both of the and
channels. Sizeable deviations from the SM values are obtained. Hence, b \rar s
\ell^+ \ell^- decay is a valuable tool for searching physics beyond the SM,
especially in the indirect searches for the fourth-generation of quarks (.Comment: 19 Pages, 10 Figures, 3 Table
Updated Safety And Efficacy Data In The Phase 1 Trial Of Patients With Mantle Cell Lymphoma (Mcl) Treated With Bruton Tyrosine Kinase (Btk) Inhibitor Zanubrutinib (Bgbâ3111)
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/149513/1/hon55_2630.pd
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