7,145 research outputs found
Suppression of bottomonia states in finite size quark gluon plasma in PbPb collisions at Large Hadron Collider
The bottomonium states due to their varying binding energies dissolve at
different temperatures and thus their nuclear modification factors and relative
yields have potential to map the properties of Quark Gluon Plasma (QGP). We
estimate the suppression of bottomonia states due to color screening in an
expanding QGP of finite lifetime and size with the conditions relevant for PbPb
collisions at LHC. The properties of states and recent results on
their dissociation temperatures have been used as ingredient in the study. The
nuclear modification factors and the ratios of yields of states are
then obtained as a function of transverse momentum and centrality. We compare
our theoretical calculations with the bottomonia yields measured with CMS in
PbPb collisions at = 2.76 TeV. The model calculations
explain the data very well.Comment: 14 pages, 5 figures, To appear in Int. j. of Mod. Phy
Interacting Multiple Model-Feedback Particle Filter for Stochastic Hybrid Systems
In this paper, a novel feedback control-based particle filter algorithm for
the continuous-time stochastic hybrid system estimation problem is presented.
This particle filter is referred to as the interacting multiple model-feedback
particle filter (IMM-FPF), and is based on the recently developed feedback
particle filter. The IMM-FPF is comprised of a series of parallel FPFs, one for
each discrete mode, and an exact filter recursion for the mode association
probability. The proposed IMM-FPF represents a generalization of the
Kalmanfilter based IMM algorithm to the general nonlinear filtering problem.
The remarkable conclusion of this paper is that the IMM-FPF algorithm retains
the innovation error-based feedback structure even for the nonlinear problem.
The interaction/merging process is also handled via a control-based approach.
The theoretical results are illustrated with the aid of a numerical example
problem for a maneuvering target tracking application
Effect of Zn doping on the Magneto-Caloric effect and Critical Constants of Mott Insulator MnV2O4
X-ray absorption near edge spectra (XANES) and magnetization of Zn doped
MnV2O4 have been measured and from the magnetic measurement the critical
exponents and magnetocaloric effect have been estimated. The XANES study
indicates that Zn doping does not change the valence states in Mn and V. It has
been shown that the obtained values of critical exponents \b{eta}, {\gamma} and
{\delta} do not belong to universal class and the values are in between the 3D
Heisenberg model and the mean field interaction model. The magnetization data
follow the scaling equation and collapse into two branches indicating that the
calculated critical exponents and critical temperature are unambiguous and
intrinsic to the system. All the samples show large magneto-caloric effect. The
second peak in magneto-caloric curve of Mn0.95Zn0.05V2O4 is due to the strong
coupling between orbital and spin degrees of freedom. But 10% Zn doping reduces
the residual spins on the V-V pairs resulting the decrease of coupling between
orbital and spin degrees of freedom.Comment: 19 pages, 9 Figures. arXiv admin note: substantial text overlap with
arXiv:1311.402
Semiclassical ordering in the large-N pyrochlore antiferromagnet
We study the semiclassical limit of the generalization of the
pyrochlore lattice Heisenberg antiferromagnet by expanding about the saddlepoint in powers of a generalized inverse spin. To leading order,
we write down an effective Hamiltonian as a series in loops on the lattice.
Using this as a formula for calculating the energy of any classical ground
state, we perform Monte-Carlo simulations and find a unique collinear ground
state. This state is not a ground state of linear spin-wave theory, and can
therefore not be a physical (N=1) semiclassical ground state.Comment: 4 pages, 4 eps figures; published versio
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