18441360
Complete analysis of photino-mediated lepton flavor violations in generalized supersymmetric models
We consider lepton flavor violations (LFV) mediated by a photino as a result of the nondiagonal slepton mass matrices in general supersymmetric models. Using the experimental upper bounds on $\stackrel{\ensuremath{\rightarrow}}{l}{l}^{\ensuremath{'}}+\ensuremath{\gamma}$ and ${\ensuremath{\mu}}^{\ensuremath{-}}+\mathrm{Ti}\ensuremath{\rightarrow}{e}^{\ensuremath{-}}+\mathrm{Ti}$ as constraints on the flavor changing slepton mass insertions, we predict the possible ranges of the upper limits on the branching ratios of other LFV processes such as $\stackrel{\ensuremath{\rightarrow}}{l}{3l}^{\ensuremath{'}}, \stackrel{\ensuremath{\rightarrow}}{\ensuremath{\tau}}{l}_{i\ensuremath{\ne}3}+{\ensuremath{\pi}}^{0}(or \ensuremath{\eta},{\ensuremath{\rho}}^{0},\ensuremath{\varphi}), {Z}^{0}\ensuremath{\rightarrow}{l}_{i}{l}_{j\ensuremath{\ne}i},$ and muonium $\ensuremath{\rightarrow}$ antimuonium conversion. Most of these decays are expected to occur with small branching ratios far below the current or future experimental search limits. We also derive constraints on the flavor conserving mass insertions from the anomalous magnetic moments of the leptons.
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.
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}
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.
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.}
14997681
NEW LIMITS FOR NEUTRINOLESS TAU DECAYS
Neutrinoless 3-prong tau lepton decays into a charged lepton and either two charged particles or one neutral meson have been searched for using 4.79fb^(-1) of data collected with the CLEO II detector at Cornell Electron Storage Ring. This analysis represents an update of a previous study and the addition of six decay channels. In all channels the numbers of events found are compatible with background estimates and branching fraction upper limits are set for 28 different decay modes. These limits are either more stringent than those set previously or represent the first attempt to find these decays.
126179603
Measurement of |V(ub) / V(cb)| (and |V(ub)|) in exclusive nonleptonic decays within the generalized factorization scheme
Within the generalized factorization scheme, we study extracting $|{V}_{\mathrm{ub}}{/V}_{\mathrm{cb}}|$ by calculating the ratios $\mathcal{B}({B}^{0}\ensuremath{\rightarrow}{D}_{s}^{(*)\ensuremath{-}}({\ensuremath{\pi}}^{+},{\ensuremath{\rho}}^{+}))/\mathcal{B}({B}^{0}\ensuremath{\rightarrow}{D}_{s}^{(*)\ensuremath{-}}{D}^{(*)+})$ including penguin effects. The ratios involving the ${B}^{0}\ensuremath{\rightarrow}{D}_{s}^{\ensuremath{-}}{D}^{+}$ mode have considerable penguin corrections $(\ensuremath{\sim}15%$ at the amplitude level), but those involving the ${B}^{0}\ensuremath{\rightarrow}{D}_{s}^{\ensuremath{-}}{D}^{*+}$ mode have relatively small penguin corrections. On the other hand, the ${B}^{0}\ensuremath{\rightarrow}{D}_{s}^{\ensuremath{-}}{D}^{+}$ mode has a smaller form-factor dependence. Therefore, these ratios complement each other in measuring ${V}_{\mathrm{ub}}{/V}_{\mathrm{cb}}.$ The theoretical uncertainty from the hadronic form factors in our method is at the level of 20%, which is comparable to the model dependence uncertainty of about 20% in the measurement of $|{V}_{\mathrm{ub}}{/V}_{\mathrm{cb}}|$ from the exclusive semileptonic B decays. Using the newest upper limit on $\stackrel{\ensuremath{\rightarrow}}{B}{D}_{s}\ensuremath{\pi}$ decay from CLEO, our method sets an upper limit $|{V}_{\mathrm{ub}}{/V}_{\mathrm{cb}}|l0.13$ which is very close to the measured values from the semileptonic B decays.
118845335
Physical Properties of the Transiting Planetary System TrES-3
We present four new transits of the planetary system TrES-3 observed between 2009 May and 2010 June. Among these, the third transit by itself indicates possible evidence for brightness disturbance, which might be a result of the planet blocking a cool starspot on the stellar surface. A total of 109 transit times, including our measurements, were used to determine the improved ephemeris with a transit epoch of 2454185.910944 ˙ 0.000072 HJED and an orbital period of 1.30618700 ˙ 0.00000015d. We analyzed the transit light curves using the JKTEBOP code and adopting the quadratic limb-darkening law. In order to derive the physical properties of the TrES-3 system, the transit parameters were combined with the empirical relations from eclipsing binary stars and stellar evolutionary
119110893
Resummation of relativistic corrections to exclusive productions of charmonia in e+e- collisions
We investigate two exclusive processes, ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}{\ensuremath{\eta}}_{c}+\ensuremath{\gamma}$ and ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}J/\ensuremath{\psi}+J/\ensuremath{\psi}$, at the center-of-momentum energy $\sqrt{s}=10.58\text{ }\text{ }\mathrm{GeV}$ within the framework of the nonrelativistic QCD factorization approach. A class of relativistic corrections is resummed to all orders in the heavy-quark velocity $v$ and the corrections are large negative. We further improve the prediction by including available QCD next-to-leading-order corrections and the interference between the QCD and relativistic corrections. The prediction for $\ensuremath{\sigma}[{e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}{\ensuremath{\eta}}_{c}+\ensuremath{\gamma}]$ is about 50 fb. In the case of ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}J/\ensuremath{\psi}+J/\ensuremath{\psi}$ the standard nonrelativistic QCD prediction for the cross section is negative. As an alternative, the vector-meson-dominance approach is employed to compute the photon-fragmentation contribution of the process, which gives the cross section $\ensuremath{\sim}1\text{ }\text{ }\mathrm{fb}$. This is an indication that the uncalculated QCD higher-order corrections may be significant. Our results can be tested against the forthcoming data from Belle II and super $B$ factories.
119113345
Order-v^4 Relativistic Corrections to Gluon Fragmentation into ^3S_1 Quarkonium
We compute the relativistic corrections to the color-singlet contribution to gluon fragmentation into a J/psi at relative order v^4, making use of the nonrelativistic QCD (NRQCD) factorization approach. The corresponding full-QCD process exhibits infrared divergences that manifest themselves as single and double poles in epsilon in 4-2epsilon dimensions. We isolate the infrared-divergent contributions and treat them analytically. In the matching of full QCD to NRQCD, the pole contributions are absorbed into long-distance NRQCD matrix elements. The renormalizations of the ultraviolet divergences of the long-distance NRQCD matrix elements involve Born and one-loop single-pole counterterm contributions and Born double-pole counterterm contributions. While the order-v^4 contribution enhances the J/psi hadroproduction rate for the color-singlet channel substantially, this contribution is not important numerically in comparison with the color-octet contributions. We also find that the ^3P_J color-octet channel in the gluon fragmentation function contributes to J/psi hadroproduction significantly in comparison with the complete contribution of next-to-leading order in alpha_s in that channel.