11,006 research outputs found
Experimental Studies of Diffractive Processes at HERA
Diffractive processes in photon-proton interactions at HERA offer the
opportunity to improve the understanding of the transition between the soft,
non-perturbative regime in hadronic interactions at and the
perturbative region at high . Recent experimental results from HERA on
inclusive diffractive scattering, exclusive vector meson production and the
properties of the hadronic final state in diffraction are reviewed. The results
are discussed in the context of current theoretical models.Comment: 7 pages, 7 figure (6 in eps, 1 in ps) talk given at XXXI
International Symposium on Multiparticle Dynamics, Sep. 1-7, 2001, Datong
China URL http://ismd31.ccnu.edu.cn
Recent results on beyond the standard model Higgs boson searches from CMS
Two extensions of the standard model, one that includes the seesaw mechanism
of type II, and the minimal supersymmetric extention to the standard model, are
studied using up to 1.6 fb^{-1} of data collected in proton-proton collisions
at sqrt{s}=7 TeV with the CMS detector at the LHC.Comment: Presented at the 2011 Hadron Collider Physics symposium (HCP-2011),
Paris, France, November 14-18 2011, 3 pages, 5 figure
Heat Conduction in One-Dimensional chain of Hard Discs with Substrate Potential
Heat conduction of one-dimensional chain of equivalent rigid particles in the
field of external on-site potential is considered. Zero diameters of the
particles correspond to exactly integrable case with divergent heat conduction
coefficient. By means of simple analytical model it is demonstrated that for
any nonzero particle size the integrability is violated and the heat conduction
coefficient converges. The result of the analytical computation is verified by
means of numerical simulation in a plausible diapason of parameters and good
agreement is observedComment: 14 pages, 7 figure
Nonlinear Breathing-like Localized Modes in C60 Nanocrystals
We study the dynamics of nanocrystals composed of C60 fullerene molecules. We
demonstrate that such structures can support long-lived strongly localized
nonlinear oscillatory modes, which resemble discrete breathers in simple
lattices. We reveal that at room temperatures the lifetime of such nonlinear
localized modes may exceed tens of picoseconds; this suggests that C60
nanoclusters should demonstrate anomalously slow thermal relaxation when the
temperature gradient decays in accord to a power law, thus violating the
Cattaneo-Vernotte law of thermal conductivity.Comment: 6 pages, 6 figure
Properties of short-range and long-range correlation energy density functionals from electron-electron coalescence
The combination of density functional theory with other approaches to the
many-electron problem through the separation of the electron-electron
interaction into a short-range and a long-range contribution is a promising
method, which is raising more and more interest in recent years. In this work
some properties of the corresponding correlation energy functionals are derived
by studying the electron-electron coalescence condition for a modified
(long-range-only) interaction. A general relation for the on-top (zero
electron-electron distance) pair density is derived, and its usefulness is
discussed with some examples. For the special case of the uniform electron gas,
a simple parameterization of the on-top pair density for a long-range only
interaction is presented and supported by calculations within the ``extended
Overhauser model''. The results of this work can be used to build
self-interaction corrected short-range correlation energy functionals.Comment: revised version, to appear in Phys. Rev.
Elliptic operators in odd subspaces
An elliptic theory is constructed for operators acting in subspaces defined
via odd pseudodifferential projections. Subspaces of this type arise as
Calderon subspaces for first order elliptic differential operators on manifolds
with boundary, or as spectral subspaces for self-adjoint elliptic differential
operators of odd order. Index formulas are obtained for operators in odd
subspaces on closed manifolds and for general boundary value problems. We prove
that the eta-invariant of operators of odd order on even-dimesional manifolds
is a dyadic rational number.Comment: 27 page
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