7604114
R-parity violation and semileptonic decays of B-meson
Abstract We investigate the effects of R -parity violation on the semileptonic decays of B -meson in the minimal supersymmetric standard model with explicit R -parity violation and discuss its physical implications. We find that the semileptonic decays of B -meson can be largely affected by R -parity violation.
1562637
Remarks on the upper bounds on the Higgs boson mass from triviality.
We study the effects of the one-loop matching conditions on Higgs boson and top quark masses on the triviality bounds on the Higgs boson mass using {beta}{sub {lambda}} with corrected two-loop coefficients. We obtain quite higher results than previous ones and observe that the triviality bounds are not nearly influenced by varying the top quark mass over the range measured at CDF and D0. The effects of typographical errors in {beta}{sub {lambda}}{sup (2)} and the one-loop matching condition on the top quark mass are negligible. We estimate the size of the effects on the triviality bounds from the one-loop matching condition on the Higgs boson mass. {copyright} {ital 1996 The American Physical Society.}
3289948
Flavour geometry and effective Yukawa couplings in the MSSM
We present a new geometric approach to the flavour decomposition of an arbitrary soft supersymmetry-breaking sector in the MSSM. Our approach is based on the geometry that results from the quark and lepton Yukawa couplings, and enables us to derive the necessary and sufficient conditions for a linearly-independent basis of matrices related to the completeness of the internal [SU(3)⊗U(1)]5 flavour space. In a second step, we calculate the effective Yukawa couplings that are enhanced at large values of tan β for general soft supersymmetry-breaking mass parameters. We highlight the contributions due to non-universal terms in the flavour decompositions of the sfermion mass matrices. We present numerical examples illustrating how such terms are induced by renormalization-group evolution starting from universal input boundary conditions, and demonstrate their importance for the flavour-violating effective Yukawa couplings of quarks.
119107944
Singlino-driven electroweak baryogenesis in the next-to-MSSM
Abstract We explore a new possibility of electroweak baryogenesis in the next-to-minimal supersymmetric standard model. In this model, a strong first-order electroweak phase transition can be achieved due to the additional singlet Higgs field. The new impact of its superpartner (singlino) on the baryon asymmetry is investigated by employing the closed-time-path formalism. We find that the CP violating source term fueled by the singlino could be large enough to generate the observed baryon asymmetry of the Universe without any conflicts with the current constraints from the non-observation of the thallium, neutron and mercury electric dipole moments.
43894133
A geometric approach to CP violation: applications to the MCPMFV SUSY model
We analyze the constraints imposed by experimental upper limits on electric dipole moments (EDMs) within the Maximally CP -and Minimally Flavour-Violating (MCPMFV) version of the MSSM. Since the MCPMFV scenario has 6 non-standard CP -violating phases, in addition to the CP -odd QCD vacuum phase θQCD, cancellations may occur among the CP -violating contributions to the three measured EDMs, those of 205Tl, the neutron and 199Hg, leaving open the possibility of relatively large values of the other CP -violating observables. We develop a novel geometric method that uses the small-phase approximation as a starting point, takes the existing EDM constraints into account, and enables us to find maximal values of other CP -violating observables, such as the EDMs of the Deuteron and muon, the CP -violating asymmetry in b→sγ decay, and the B s mixing phase. We apply this geometric method to provide upper limits on these observables within specific benchmark supersymmetric scenarios, including extensions that allow for a non-zero θQCD.
121878109
Proton decay with a light gravitino or axino
We consider proton decay in supersymmetric models with a gravitino or axino lighter than the proton. This consideration leads to a stringent limit on the R-parity and B-violating Yukawa coupling of the superpotential operator U{sub i}{sup c}D{sub j}{sup c}D{sub k}{sup c} as {lambda}{sub 112}{sup {double_prime}}{le}10{sup {minus}15}(m{sub 3/2}/eV) for a light gravitino, and {lambda}{sub 112}{sup {double_prime}}{le}10{sup {minus}15}(F{sub a}/10{sup 10} GeV) for a light Dine-Fischler-Srednicki-Zhitnitskii axino. For the hadronic axino, the constraint is weakened by a factor of 10{sup 3}. {copyright} {ital 1997} {ital The American Physical Society}
15708185
COMPOSITE OPERATORS AND TOPOLOGICAL CONTRIBUTIONS IN GAUGE THEORY
In D-dimensional gauge theory with a kinetic term based on p-form tensor gauge field, we introduce a gauge-invariant operator associated with the composite form from an electric (p - 1)-brane and a magnetic (q - 1)-brane in D = p + q + 1 space–time dimensions. By evaluating the partition function of this operator, we show that the expectation value of this operator gives rise to the topological contributions identical to those in gauge theory with a topological Chern–Simons BF term.
403273
First determination of the weak charge of the proton.
The Q(weak) experiment has measured the parity-violating asymmetry in ep elastic scattering at Q(2)=0.025(GeV/c)(2), employing 145 μA of 89% longitudinally polarized electrons on a 34.4 cm long liquid hydrogen target at Jefferson Lab. The results of the experiment's commissioning run, constituting approximately 4% of the data collected in the experiment, are reported here. From these initial results, the measured asymmetry is A(ep)=-279±35 (stat) ± 31 (syst) ppb, which is the smallest and most precise asymmetry ever measured in ep scattering. The small Q(2) of this experiment has made possible the first determination of the weak charge of the proton Q(W)(p) by incorporating earlier parity-violating electron scattering (PVES) data at higher Q(2) to constrain hadronic corrections. The value of Q(W)(p) obtained in this way is Q(W)(p)(PVES)=0.064±0.012, which is in good agreement with the standard model prediction of Q(W)(p)(SM)=0.0710±0.0007. When this result is further combined with the Cs atomic parity violation (APV) measurement, significant constraints on the weak charges of the up and down quarks can also be extracted. That PVES+APV analysis reveals the neutron's weak charge to be Q(W)(n)(PVES+APV)=-0.975±0.010.
118999114
CP violation in the semileptonic B(lepton 4) (B ---> D pi lepton neutrino) decays: multi - Higgs doublet model and scalar leptoquark models
$\mathrm{CP}$ violation from physics beyond the standard model is investigated in ${B}_{l4}$ decays: $\stackrel{\ensuremath{\rightarrow}}{B}D\ensuremath{\pi}l{\overline{\ensuremath{\nu}}}_{l}.$ In the decay process, we include various excited states as intermediate states decaying to the final hadrons, $D+\ensuremath{\pi}$. We consider the semileptonic decay to a tau lepton family as well. $\mathrm{CP}$ violation is implemented through complex scalar-fermion couplings in the multi-Higgs-doublet model and scalar-leptoquark models beyond the standard model. With these complex couplings, we calculate the $\mathrm{CP}$-odd rate asymmetry and the optimal asymmetry. We find that for ${B}_{\ensuremath{\tau}4}$ decays the optimal asymmetry is sizable and can be detected at $1\ensuremath{\sigma}$ level with about ${10}^{6}\char21{}{10}^{7}B$-meson pairs, for maximally allowed values of $\mathrm{CP}$-odd parameters in those extended models.
3069819
Test of factorization hypothesis from exclusive nonleptonic B decays
We investigate the possibility of testing the factorization hypothesis in nonleptonic exclusive decays of the B meson. In particular, we consider the nonfactorizable ${B}^{0}\ensuremath{\rightarrow}{D}^{(*)+}{D}_{s}^{(*)\ensuremath{-}}$ modes and ${B}^{0}\ensuremath{\rightarrow}{D}^{(*)+}({\ensuremath{\pi}}^{\ensuremath{-}},{\ensuremath{\rho}}^{\ensuremath{-}})$ known as well-factorizable modes. By taking the ratios $\mathcal{B}({B}^{0}\ensuremath{\rightarrow}{D}^{(*)+}{D}_{s}^{(*)\ensuremath{-}})/\mathcal{B}[{B}^{0}\ensuremath{\rightarrow}{D}^{(*)+}({\ensuremath{\pi}}^{\ensuremath{-}},{\ensuremath{\rho}}^{\ensuremath{-}})],$ we find that under the present theoretical and experimental uncertainties there is no evidence for the breakdown of the factorization description for heavy-heavy decays of the B meson.
116536256
Two-body B meson decays to eta and eta-prime Observation of B ---> eta-prime K