2,919 research outputs found
Topics on Hydrodynamic Model of Nucleus-Nucleus Collisions
A survey is given on the applications of hydrodynamic model of
nucleus-nucleus collisons, focusing especially on i) the resolution of
hydrodynamic equations for arbitrary configurations, by using the
smoothed-particle hydrodynamic approach; ii) effects of the event-by-event
fluctuation of the initial conditions on the observables; iii) decoupling
criteria; iv) analytical solutions; and others.Comment: 30 pages, 29 figures; corrected typo
On the necessity to include event-by-event fluctuations in experimental evaluation of elliptical flow
Elliptic flow at RHIC is computed event-by-event with NeXSPheRIO. We show
that when symmetry of the particle distribution in relation to the reaction
plane is assumed, as usually done in the experimental extraction of elliptic
flow, there is a disagreement between the true and reconstructed elliptic flows
(15-30% for =0, 30% for =0.5 GeV). We suggest a possible way to
take into account the asymmetry and get good agreement between these elliptic
flows
Effects of LatticeQCD EoS and Continuous Emission on Some ObseErvables
Effects of lattice-QCD-inspired equations of state and continuous emission on
some observables are discussed, by solving a 3D hydrodynamics. The particle
multiplicity as well as v2 are found to increase in the mid-rapidity. We also
discuss the effects of the initial-condition fluctuations.Comment: 6 pages, 10 figures, prepared for Workshop on Particle Correlations
and Fentoscopy, Kromeriz (Czech Republic), Aug. 15-17,200
First results from the VIMOS-IFU survey of gravitationally lensing clusters at z~0.2
We present the on-going observational program of a VIMOS Integral Field Unit
survey of the central regions of massive, gravitational lensing galaxy clusters
at redshift z~0.2. We have observed six clusters using the low-resolution blue
grism (R about 200), and the spectroscopic survey is complemented by a wealth
of photometric data, including Hubble Space Telescope optical data and near
infrared VLT data. The principal scientific aims of this project are: the study
of the high-z lensed galaxies, the transformation and evolution of galaxies in
cluster cores and the use of multiple images to constrain cosmography. We
briefly report here on the first results from this project on the clusters
Abell 2667 and Abell 68.Comment: 5 pages, 5 figures. To appear in "Sciences Perspectives for 3D
Spectroscopy. ESO Astrophysics Symposia". Ed by M.Kissler-Patig, M.M. Roth
and J.R. Wals
quantum cosmological solutions for Class A Bianchi Models
We find solutions for quantum Class A Bianchi models of the form generalizing the results obtained by Moncrief and Ryan in
standard quantum cosmology. For the II and IX Bianchi models there are other
solutions , to the Hamilton-Jacobi
equation for which is necessarely zero, in contrast with solutions
found in supersymmetric quantum cosmology.Comment: 15 pages, Late
Orbital Order Effect of Two-Dimensional Spin Gap System for CaV4O9
Effects of possible orbital order in magnetic properties of two-dimensional
spin gap system for CaVO are investigated theoretically. After
analyzing experimental data, we show that single orbital models assumed in the
literature are insufficient to reproduce the data. To understand the origin of
the discrepancy, we assume that in state of V, and
orbitals have substantial contributions in the lowest-energy atomic level which
leads to a double-degeneracy. We study possible configurations of the orbital
order. By exact diagonalization and perturbation expansion, we calculate the
susceptibility, wavenumber dependence of low-lying excitations and equal-time
spin-spin correlations which is related to integrated intensity of the neutron
inelastic scattering. These quantities sensitively depend on the configuration
of the orbital order. The calculated results for some configurations of the
orbital order reproduce many experimental results much better than the previous
single-orbital models. However some discrepancy still remains to completely
reproduce all of the reported experimental results. To understand the origin of
these discrepancies, we point out the possible importance of the partially
occupied orbital in addition to orbital order of partially filled
and orbitals.Comment: 19 pages LATEX, 15 postscript figures, using jpsj.sty,to be published
in J.Phys.Soc.Jpn. Vol.67 No.2 (1998
NeXSPheRIO results on elliptic flow at RHIC and connection with thermalization
Elliptic flow at RHIC is computed event-by-event with NeXSPheRIO. Reasonable
agreement with experimental results on is obtained. Various effects
are studied as well: reconstruction of impact parameter direction, freeze out
temperature, equation of state (with or without crossover), emission mecanism.Comment: Contribution to the Proceedings of the Quark-Gluon Plasma
Thermalization workshop. Content slightly increase
Classical instability in Lovelock gravity
We introduce a simple method for the investigation of the classical stability
of static solutions with a horizon in Lovelock gravity. The method is
applicable to the investigation of high angular momentum instabilities, similar
to those found by Dotti and Gleiser for Gauss-Bonnet black holes. The method
does not require the knowledge of the explicit analytic form of the black hole
solution. In this paper we apply our method to a case where the explicit
solution is known and show that it identifies correctly the resulting unstable
modes.Comment: 13 pages, 2 figure
Minisuperspace Examples of Quantization Using Canonical Variables of the Ashtekar Type: Structure and Solutions
The Ashtekar variables have been use to find a number of exact solutions in
quantum gravity and quantum cosmology. We investigate the origin of these
solutions in the context of a number of canonical transformations (both complex
and real) of the basic Hamiltonian variables of general relativity. We are able
to present several new solutions in the minisuperspace (quantum cosmology)
sector. The meaning of these solutions is then discussed.Comment: 23 pages, latex, 3 figures (uuencoded, separate file
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