184,789 research outputs found
Accurate evaluation of the Green's function of disordered graphenes
An accurate simulation of Green's function and self-energy function of
non-interacting electrons in disordered graphenes are performed. Fundamental
physical quantities such as the elastic relaxation time {\tau}e, the phase
velocity vp, and the group velocity vg are evaluated. New features around the
Dirac point are revealed, showing hints that multi-scattering induced
hybridization of Bloch states plays an important role in the vicinity of the
Dirac point.Comment: 4 figure
A review of indirect searches for particle dark matter
The indirect detection of dark matter annihilation and decay using
observations of photons, charged cosmic rays, and neutrinos offers a promising
means of identifying the particle nature of this elusive component of the
universe. The last decade has seen substantial advances in observational data
sets, complemented by new insights from numerical simulations, which together
have enabled for the first time strong constraints on dark matter particle
models, and have revealed several intriguing hints of possible signals. This
review provides an introduction to indirect detection methods and an overview
of recent results in the field.Comment: 32 pages, 6 figures; invited review, accepted to Contemporary Physic
Temporal and Spectral Properties of Gamma-Ray Flashes
The temporal and spectral properties of terrestrial gamma-ray flashes (TGFs)
are studied. The delay of low energy photons relative to high energy ones in
the gamma-ray variations of the TGFs with high signal to noise ratio has been
revealed by an approach of correlation analysis in the time domain on different
time scales. The temporal structures of the TGFs in high energy band are
usually narrower than that in low energy band. The spectral hardness has a
general trend of decreasing with time in a flash. The observed temporal and
spectral characteristics give constraints and valuable hints on the flash
production mechanism.Comment: accepted for publication in GRL (7 pages, 3 figures
Unscrambling New Models for Higher-Energy Physics
There is strong evidence that new physical degrees of freedom and new
phenomena exist and may be revealed in future collider experiments. The best
hints of what this new physics might be are provided by electroweak symmetry
breaking. I briefly review certain theories for physics beyond the standard
model, including the top-quark seesaw model and universal extra dimensions. A
common feature of these models is the presence of vector-like quarks at the TeV
scale. Then I discuss the role of a linear collider in disentangling
this new physics.Comment: 10 pages, LaTeX, uses aipproc.cls and aipproc.sty. Plenary talk given
at the 5th International Linear Collider Workshop, Fermilab, Oct. 24-28, 200
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