Split Generation in the SUSY Mass Spectrum and B_s-{\bar B}_s Mixing

We show that the like-sign di-muon anomaly reported recently by the D0 Collaboration can be explained in the supersymmetric standard model (SM) if the squarks and the sleptons in the first two generations have relatively small, but degenerate mass spectrum, and those in the third generation are larger as O(1-10)TeV. This split generation model provides large contributions to the B_s-{\bar B}_s mixing, although most of the FCNC's are suppressed due to the large masses of the third generation squarks or the GIM mechanism partially acting on the first and second generations.Comment: 15 pages, 1 figur

Color Superconductivity from Supersymmetry

A supersymmetric composite model of color superconductivity is proposed. Quarks and diquarks are dynamically generated as composite fields by a newly introduced strong gauge dynamics. It is shown that the condensation of the scalar component of the diquark supermultiplet occurs when the chemical potential becomes larger than some critical value. We believe that the model well captures aspects of the diquark condensate behavior and helps our understanding of the diquark dynamics in real QCD. The results obtained here might be useful when we consider a theory composed of quarks and diquarks.Comment: 4 pages, 2 figures, An error in Eq.(10) correcte

The Decay of the Inflaton in No-scale Supergravity

We study the decay of the inflaton in no-scale supergravity and show that decay due to the gravitational interactions through supergravity effects is highly suppressed relative to the case in minimal supergravity or models with a generic Kahler potential. We also show that decay to gravitinos is suppressed. We demonstrate that decay and sufficient reheating are possible with the introduction of a non-trivial gauge kinetic term. This channel may be dominant in no-scale supergravity, yet yields a re-heating temperature which is low enough to avoid the gravitino problem while high enough for Big Bang Nucleosynthesis and baryogenesis.Comment: Added the footnote in the conclusion section which discusses the constrains on the explicit inflaton couplings to the matter fields via non-renormalizable operators. To appear in JCA

Neutrino processes in the K0K^0 condensed phase of color flavor locked quark matter

We study weak interactions involving Goldstone bosons in the neutral kaon condensed phase of color flavor locked quark matter. We calculate the rates for the dominant processes that contribute to the neutrino mean free p ath and to neutrino production. A light $K^+$ state, with a mass $\tilde{m}_{K^+} \propto (\Delta/\mu) (\Delta/m_s)(m_d-m_u)$, where $\mu$ and $\Delta$ are the quark chemical potential and superconducting gap respectively, is shown to play an important role. We identify unique characteristics of weak interaction rates in this novel phase and discuss how they might influence neutrino emission in core collapse supernova and neutron stars.Comment: 21 pages, 4 figure

Duality and Superconvergence Relation in Supersymmetric Gauge Theories

We investigate the phase structures of various N=1 supersymmetric gauge theories including even the exceptional gauge group from the viewpoint of superconvergence of the gauge field propagator. Especially we analyze in detail whether a new type of duality recently discovered by Oehme in $SU(N_c)$ gauge theory coupled to fundamental matter fields can be found in more general gauge theories with more general matter representations or not. The result is that in the cases of theories including matter fields in only the fundamental representation, Oehme's duality holds but otherwise it does not. In the former case, superconvergence relation might give good criterion to describe the interacting non-Abelian Coulomb phase without using some information from dual magnetic theory.Comment: 20 pages, LaTe

The axial anomaly and the phases of dense QCD

The QCD axial anomaly, by coupling the chiral condensate and BCS pairing fields of quarks in dense matter, leads to a new critical point in the QCD phase diagram \cite{HTYB,chiral2}, which at sufficiently low temperature should terminate the line of phase transitions between chirally broken hadronic matter and color superconducting quark matter. The critical point indicates that matter at low temperature should cross over smoothly from the hadronic to the quark phase, as suggested earlier on the basis of symmetry. We review here the arguments, based on a general Ginzburg-Landau effective Lagrangian, for the existence of the new critical point, as well as discuss possible connections between the QCD phase structure and the BEC-BCS crossover in ultracold trapped atomic fermion systems at unitarity. and implications for the presence of quark matter in neutron stars.Comment: 8 pages, Proceedings of Quark Matter 2008, Jaipu

Probing High Reheating Temperature Scenarios at the LHC with Long-Lived Staus

We investigate the possibility of probing high reheating temperature scenarios at the LHC, in supersymmetric models where the gravitino is the lightest supersymmetric particle, and the stau is the next-to-lightest supersymmetric particle. In such scenarios, the big-bang nucleosynthesis and the gravitino abundance give a severe upper bound on the gluino mass. We find that, if the reheating temperature is \sim 10^8 GeV or higher, the scenarios can be tested at the LHC with an integrated luminosity of O(1 fb^{-1}) at \sqrt{s}=7 TeV in most of the parameter space.Comment: 17 pages, 5 figures, minor modification

Vacuum Stability Bound on Extended GMSB Models

Extensions of GMSB models were explored to explain the recent reports of the Higgs boson mass around 124-126 GeV. Some models predict a large mu term, which can spoil the vacuum stability of the universe. We study two GMSB extensions: i) the model with a large trilinear coupling of the top squark, and ii) that with extra vector-like matters. In both models, the vacuum stability condition provides upper bounds on the gluino mass if combined with the muon g-2. The whole parameter region is expected to be covered by LHC at sqrt{s} = 14 TeV. The analysis is also applied to the mSUGRA models with the vector-like matters.Comment: 22 pages, 4 figure