Dark Matter in SuperGUT Unification Models

After a brief update on the prospects for dark matter in the constrained version of the MSSM (CMSSM) and its differences with models based on minimal supergravity (mSUGRA), I will consider the effects of unifying the supersymmetry-breaking parameters at a scale above M_{GUT}. One of the consequences of superGUT unification, is the ability to take vanishing scalar masses at the unification scale with a neutralino LSP dark matter candidate. This allows one to resurrect no-scale supergravity as a viable phenomenological model.Comment: 12 pages, 16 figures, To be published in the Proceedings of the 6th DSU Conference, Leon, Mexico, ed. D. Delepin

The Semileptonic BB to K1(1270,1400)K_1(1270,1400) Decays in QCD Sum Rules

We analyze the semileptonic rare decays of $B$ meson to $K_{1} (1270)$ and $K_{1} (1400)$ axial vector mesons. The $B\to K_{1} (1270,1400) \ell^+ \ell^-$ decays are significant flavor changing neutral current decays of the $B$ meson. These decays are sensitive to the new physics beyond SM, since these processes are forbidden at tree level at SM. These decays occurring at the quark level via $b\to s \ell^+ \ell^-$ transition, also provide new opportunities for calculating the CKM matrix elements $V_{bt}$ and $V_{ts}$. In this study, the transition form factors of the $B\to K_{1} (1270,1400) \ell^+ \ell^-$ decays are calculated using three-point QCD sum rules approach. The resulting form factors are used to estimate the branching fractions of these decays.Comment: 18 pages, 7 figures, version to appear in JP

Implications of the Anomalies in B_s^0-\bar{B}_s^0 Mixing for Anomalous Tensor Couplings

Motivated by the recently observed anomalous large dimuon charge asymmetry in neutral B decays and the unexpected large CP phase in the mixing-induced CP asymmetry for B_s-->J/\psi\phi decay, we study the effects of the anomalous tensor couplings to pursue possible solution. With the constraints from the obsevables \phi^{J/\psi\phi}_s, a_{sl}^s and \Delta M_s, the parameter spaces are severely restricted. Numerically, we find the anomalies in B_s^0-\bar{B}_s^0 mixing system could be moderated simultaneously by the contributions induced by the color-singlet or color-octet tensor operators with their respective nontrivial new weak phase \phi_{T1}\approx28.0(15.6) degree or \phi_{T8}\approx-62.1(-74.2) degree and relevant strength parameters g_{T1}\approx6.7(8.5)\times10^{-2} or g_{T8}\approx1.9(2.4)\times10^{-2} for the CP-violating phase \phi^{J/\psi\phi}_s=-0.77(+0.29,-0.37)(-2.36(+0.37,-0.29)), respectively.Comment: 14pages, 2 figures, 3table

Mixed Bino-Wino-Higgsino Dark Matter in Gauge Messenger Models

Almost degenerate bino and wino masses at the weak scale is one of unique features of gauge messenger models. The lightest neutralino is a mixture of bino, wino and higgsino and can produce the correct amount of the dark matter density if it is the lightest supersymmetric particle. Furthermore, as a result of squeezed spectrum of superpartners which is typical for gauge messenger models, various co-annihilation and resonance regions overlap and very often the correct amount of the neutralino relic density is generated as an interplay of several processes. This feature makes the explanation of the observed amount of the dark matter density much less sensitive to fundamental parameters. We calculate the neutralino relic density assuming thermal history and present both spin independent and spin dependent cross sections for the direct detection. We also discuss phenomenological constraints from b to s gamma and muon g-2 and compare results of gauge messenger models to well known results of the mSUGRA scenario.Comment: 27 pages, 9 figures, references added, version to appear at JCA

The impact of XENON100 and the LHC on Supersymmetric Dark Matter

The effect of 2010 and 2011 LHC data are discussed in connection to the potential for the direct detection of supersymmetric dark matter. The impact of the recent XENON100 results are contrasted to these predictions.Comment: 14 pages, 23 figures, To be published in the Proceedings of the 7th DSU Conference, Beijing Chin

A method of measuring cos(2 beta) using a time-dependent dalitz plot analysis of B-0 -> D-CP π+π-

We present a feasibility study of a previously outlined method for measuring both the sine and the cosine of twice the Cabibbo-Kobayashi-Maskawa (CKM) Unitarity Triangle angle beta using a time-dependent Dalitz plot analysis of B-0 -> D pi(+)pi(-) decays, where the neutral D meson is reconstructed in decays to CP eigenstates. We show that this method can be used at the B factories to make a measurement of cos(2 beta) that is competitive with, or more precise than, other techniques using different quark-level transitions, while sin(2 beta) can be measured to a better precision than any existing measurement using b -> c (u) over bard transitions. Furthermore, this technique has great potential to be employed at LHCb