38,141 research outputs found
New Formulas and Predictions for Running Fermion Masses at Higher Scales in SM, 2HDM, and MSSM
Including contributions of scale-dependent vacuum expectation values, we
derive new analytic formulas and obtain substantially different numerical
predictions for the running masses of quarks and charged-leptons at higher
scales in the SM, 2HDM and MSSM. These formulas exhibit significantly different
behaviours with respect to their dependence on gauge and Yukawa couplings than
those derived earlier. At one-loop level the masses of the first two
generations are found to be independent of Yukawa couplings of the third
generation in all the three effective theories in the small mixing limit.
Analytic formulas are also obtained for running in 2HDM and
MSSM. Other numerical analyses include study of the third generation masses at
high scales as functions of low-energy values of and SUSY scale
GeV.Comment: 42 pages RevTeX, including 16 figures. Typos corrected and one
reference adde
Final-State Interaction as the Origin of the Cronin Effect
Instead of adhering to the usual explanation of the Cronin effect in terms of
the broadening of the parton transverse momentum in the initial state, we show
that the enhancement of hadron production at moderate in d+Au collisions
is due to the recombination of soft and shower partons in the final state. Such
a mechanism can readily explain the decrease of the Cronin effect with
increasing rapidity. Furthermore, the effect should be larger for protons than
for pions.Comment: 4 RevTeX pages including 3 figures and 1 table; Some notational
changes and a corrected referenc
Neutrino Masses and Mixings in a Minimal SO(10) Model
We consider a minimal formulation of SO(10) Grand Unified Theory wherein all
the fermion masses arise from Yukawa couplings involving one 126 and one 10 of
Higgs multiplets. It has recently been recognized that such theories can
explain, via the type-II seesaw mechanism, the large \nu_\mu - \nu_\tau mixing
as a consequence of b-tau unification at the GUT scale. In this picture,
however, the CKM phase \delta lies preferentially in the second quadrant, in
contradiction with experimental measurements. We revisit this minimal model and
show that the conventional type-I seesaw mechanism generates phenomenologically
viable neutrino masses and mixings, while being consistent with CKM CP
violation. We also present improved fits in the type-II seesaw scenario and
suggest fully consistent fits in a mixed scenario.Comment: 27 pages, 13 eps figures, revtex4; references added, some minor
correction
Nonequilibrium Dynamics of the Complex Ginzburg-Landau Equation. I. Analytical Results
We present a detailed analytical and numerical study of nonequilibrium
dynamics for the complex Ginzburg-Landau (CGL) equation. In particular, we
characterize evolution morphologies using spiral defects. This paper (referred
to as ) is the first in a two-stage exposition. Here, we present
analytical results for the correlation function arising from a single-spiral
morphology. We also critically examine the utility of the Gaussian auxiliary
field (GAF) ansatz in characterizing a multi-spiral morphology. In the next
paper of this exposition (referred to as ), we will present detailed
numerical results.Comment: 21 pages, 7 figure
Spin polarized STM spectra of Dirac Fermions on the surface of a topological insulator
We provide a theory for the tunneling conductance of Dirac Fermions on
the surface of a topological insulator as measured by a spin-polarized scanning
tunneling microscope tip for low bias voltages . We show that
exhibits an unconventional dependence on the direction of magnetization of the
tip and can be used to measure the magnitude of the local out-of-plane spin
orientation of the Dirac Fermions on the surface. We also demonstrate that if
the in-plane rotational symmetry on the surface of the topological insulator is
broken by an external field, then acquires a dependence on the azimuthal
angle of the magnetization of the tip. We explain the role of the Dirac
Fermions in this unconventional behavior and suggest experiments to test our
theory.Comment: 7 pages, 5 Fig
- …