15949027
CP violation and matter effect for a variable earth density in very long baseline experiments
Abstract The perturbative treatment of subdominant oscillation and matter effect in neutrino beams/superbeams, propagating over long baselines and being used to look for CP violation, is studied here for a general matter density function varying with distance. New lowest order analytic expressions are given for different flavour transition and survival probabilities in a general neutrino mixing basis and a variable earth matter density profile. It is demonstrated that the matter effect in the muon neutrino (antineutrino) flavour survival probability vanishes to this order, provided the depletion, observed for atmospheric muon neutrinos and antineutrinos at super-Kamiokande, is strictly maximal. This result is independent of the earth density profile and the distance L between the source and the detector. In the general variable density case we show that one cannot separate the matter induced asymmetry from a genuine CP effect by keeping two detectors at distances L 1 and L 2 from the source while maintaining a fixed ratio L 1 / E 1 = L 2 / E 2 . This needs to be done numerically and we estimate the asymmetry generated by the earth matter effect with particular density profiles and some chosen parameters for very long baseline neutrino oscillation experiments.
119370491
Oblique corrections and the quadratic approximation in electroweak precision testing
This paper is withdrawn. A revised and expanded version of this work is available as hep-ph/9603323.
121584805
Current-commutators and high energy hadron production in e+e− annihilation
Abstract We consider the asymptotic behavior of the structure-functions for the process e + e − → H + everything (where H is a detectable hadron) in terms of commutators involving the electromagnetic current.
31086876
Stringent low-energy mass constraints in no-scale supergravity.
Spectacular mass constraints are shown to exist at low energies in minimal no-scale supergravity theories. The top quark cannot be too light, the lowest-lying Higgs particle cannot be too heavy, and the pseudoscalar Higgs boson must weigh nearly a quarter as much as the gluino.
125018064
Supersymmetry working group report, 'From strings to LHC' workshop, Goa, (January, 2007)
122353884
Parton description of the forward peak in single particle electroproduction with highly virtual photons
The parton mode or the reaction eN→eAB (N = nucleon, A, B = hadrons) in the fixed ω Bj limit is used to discuss the width of the corresponding forward peak as a function of the photon mass.
121472335
Supersymmetry at high density
119942524
Remarks on the finite temperature effect in supersymmetric quantum mechanics
Using the thermofield dynamics formalism the authors study the effect of temperature on supersymmetry within the context of supersymmetric quantum mechanics. The model considered involves an interaction not of polynomial type and it is shown that the finite-temperature effect causes spontaneous breaking of supersymmetry.
120591896
A note on supersymmetry and magnetic fields
ConclusionIn the present article we have considered two supersymmetric non-abelian gauge theories in the presence of an external magnetic field. In has been shown that the effect of the magnetic field breaks suppersymmetry at the one-loop level; however, if supersymmetry is already broken spontaneously at the tree level, then the magnetic field effect does not restore it at the one-loop level. These facts could be used in SUSY GUT models (which are used to describe the early universe), to study phase transition in those models.
119136395
Exact solutions of the (2+1) Dimensional Dirac equation in a constant magnetic field in the presence of a minimal length
We study the (2+1) dimensional Dirac equation in an homogeneous magnetic field (relativistic Landau problem) within a minimal length, or generalized uncertainty principle -GUP-, scenario. We derive exact solutions for a given explicit representation of the GUP and provide expressions of the wave functions in the momentum representation. We find that in the minimal length case the degeneracy of the states is modified and that there are states that do not exist in the ordinary quantum mechanics limit (\beta -->0). We also discuss the mass-less case which may find application in describing the behavior of charged fermions in new materials like Graphene.
121026122
A Variational approach to the Liouville model
We perform a variational analysis of the Liouville model. In particular we evaluate the effective potential and examine the possibility of restoring translation invariance.