Can a gravitational wave and a magnetic monopole coexist?

We investigate the behavior of small perturbations around the Kaluza-Klein monopole in the five dimensional space-time. We find that the even parity gravitational wave does not propagate in the five dimensional space-time with Kaluza-Klein monopole provided that the gravitational wave is constant in the fifth direction. We conclude that a gravitational wave and a U(1) magnetic monopole do not coexist in five dimensional Kaluza-Klein spacetime.Comment: 10 pages, LaTeX. To appear in Modern Physics Letters

Thermal leptogenesis in a supersymmetric neutrinophilic Higgs model

We investigate thermal leptogenesis in a supersymmetric neutrinophilic Higgs model by taking phenomenological constraints into account, where, in addition to the minimal supersymmetric standard model, we introduce an extra Higgs field with a tiny vacuum expectation value (VEV) which generates neutrino masses. Thanks to this tiny VEV of the neutrinophilic Higgs, our model allows to reduce the mass of the lightest right-handed (s)neutrino to be ${\cal O}(10^5)$ GeV as keeping sufficiently large CP asymmetry in its decay. Therefore, the reheating temperature after inflation is not necessarily high, hence this scenario is free from gravitino problem.Comment: 5 pages, 1 figur

MANX: A 6D Ionization-Cooling Experiment

Six-dimensional ionization cooling of muons is essential for muon colliders and possibly beneficial for neutrino factories. An experiment to demonstrate six-dimensional ionization cooling using practical apparatus is presented. It exploits recent innovative ideas that may lead to six-dimensional muon-cooling channels with emittance reduction approaching that needed for high-luminosity muon colliders.Comment: 3 pages, 4 figures, to appear in Proceedings of the 9th International Workshop on Neutrino Factories, Superbeams, and Betabeams (NuFact07), August 6-11, 2007, Okayama University, Japa

Neutrino Scattering on Glass: NuSOnG

These proceedings describe the physics goals and initial design for a new experiment: NuSOnG -- Neutrino Scattering On Glass. The design will yield about two orders of magnitude higher statistics than previous high energy neutrino experiments, observed in a detector optimized for low hadronic energy and electromagnetic events. As a result, the purely weak processes $\nu_{\mu}+e^- \to \nu_{\mu}+ e^-$ and $\nu_{\mu}+ e^- \to \nu_e + \mu^-$ (inverse muon decay) can be measured with high accuracy for the first time. This allows important precision electroweak tests and well as direct searches for new physics. The high statistics also will yield the world's largest sample of Deep Inelastic (DIS) events for precision parton distribution studies.Comment: Proceedings of NuFact0

Nuclear effects in Neutrino Nuclear Cross-sections

Nuclear effects in the quasielastic and inelastic scattering of neutrinos(antineutrinos) from nuclear targets have been studied. The calculations are done in the local density approximation which take into account the effect of nucleon motion as well as renormalisation of weak transition strengths in the nuclear medium. The inelastic reaction leading to production of pions is calculated in a $\Delta$ dominance model taking into account the renormalization of $\Delta$ properties in the nuclear medium.Comment: 4 pages,3 figures, Ninth International Workshop on Neutrino Factories, Superbeams and Betabeams (NuFact07), August 6-11, 2007, Okayama University, Okayama, Japa

Symmetric Tensor Decomposition Description of Fermionic Many-Body Wavefunctions

The configuration interaction (CI) is a versatile wavefunction theory for interacting fermions but it involves an extremely long CI series. Using a symmetric tensor decomposition (STD) method, we convert the CI series into a compact and numerically tractable form. The converted series encompasses the Hartree-Fock state in the first term and rapidly converges to the full-CI state, as numerically tested using small molecules. Provided that the length of the STD-CI series grows only moderately with the increasing complexity of the system, the new method will serve as one of the alternative variational methods to achieve full-CI with enhanced practicability.Comment: 10 pages, 6 figure

Chiral Symmetry and Neutrino Pion Production off the Nucleon

The neutrino pion production off the nucleon is traditionally described in the literature by means of the weak excitation of the Delta(1232) resonance and its subsequent decay into N pi. Here, we present results from a model that includes also some background terms required by chiral symmetry. We show that the contribution of these terms is sizeable and leads to significant effects in total and partially integrated pion production cross sections at intermediate energies of interest for neutrino oscillation experiments. Finally, we discuss parity-violating contributions to the pion angular differential cross section induced by the interference of these non-resonant terms with the Delta piece.Comment: To appear in the proceedings of 9th International Workshop On Neutrino Factories, Superbeams and Betabeams (NuFact07) August 6-11, 2007, Okayama University, Japa

Global NLO Analysis of Nuclear Parton Distribution Functions

Nuclear parton distribution functions (NPDFs) are determined by a global analysis of experimental measurements on structure-function ratios F_2^A/F_2^{A'} and Drell-Yan cross section ratios \sigma_{DY}^A/\sigma_{DY}^{A'}, and their uncertainties are estimated by the Hessian method. The NPDFs are obtained in both leading order (LO) and next-to-leading order (NLO) of \alpha_s. As a result, valence-quark distributions are relatively well determined, whereas antiquark distributions at x>0.2 and gluon distributions in the whole x region have large uncertainties. The NLO uncertainties are slightly smaller than the LO ones; however, such a NLO improvement is not as significant as the nucleonic case.Comment: 3 pages, LaTeX, 4 eps files, to be published in the AIP proceedings of the 9th International Workshop on Neutrino Factories, Superbeams and Betabeams (NuFact07), Okayama, Japan, August 6 - 11, 2007. A code for calculating our nuclear parton distribution functions and their uncertainties can be obtained from http://research.kek.jp/people/kumanos/nuclp.htm

A New Triangulated Category for Rational Surface Singularities

In this short paper we introduce a new triangulated category for rational surface singularities which in the non-Gorenstein case acts as a substitute for the stable category of matrix factorizations. The category is formed as a Frobenius quotient of the category of special CM modules, and we classify the relatively projective-injective objects and thus describe the AR quiver of the quotient. Connections to the corresponding reconstruction algebras are also discussed.Comment: 15 pages, minor changes. Final versio