4,888 research outputs found
Anisotropic flow of identified particles in Au+Au collisions at AGS energy
Anisotropic flow of protons, , , deuterons, tritons, He,
and He is analyzed as a function of transverse momentum for different
centralities of the collision.Comment: RevTex, 4 pages, 4 figures included as eps files. To be published in
the Proceedings of QM97, Tsukuba, Japa
Bottomonium dipion transitions
Dipion transitions of the subthreshold bottomonium levels with are studied in the
framework of the chiral decay Lagrangian, derived earlier. The channels are considered in the intermediate state and
realistic wave functions of and are used in the
overlap matrix elements. Imposing the Adler zero requirement on the transition
matrix element, one obtains 2d and 1d dipion spectra in reasonable agreement
with experiment.Comment: 34 pages, 18 figure
Vorticity and particle polarization in heavy ion collisions (experimental perspective)
The recent measurements of the global polarization and vector meson spin
alignment along the system orbital momentum in heavy ion collisions are briefly
reviewed. A possible connection between the global polarization and the chiral
anomalous effects is discussed along with possible experimental checks. Future
directions, in particular those aimed on the detailed mapping of the vorticity
fields, are outlined. The Blast Wave model is used for an estimate of the
anisotropic flow effect on the vorticity component along the beam direction. We
also point to a possibility of a circular pattern in the vorticity field in
asymmetric, e.g. Cu+Au, central collisions.Comment: 8 pages, Proceedings of the invited talk at Strangeness in Quark
Matter 2017 Conference, Utrecht, Netherlands, July 201
Semiclassical Calculation of Photon-Stimulated Schwinger Pair Creation
We consider the electron-positron pair creation by a photon in an external
constant electric field. The presented treatment is based on a purely
quasiclassical calculation of the imaginary part of the on-shell photon
polarization operator. By using this approach we find the pair production rate
for photons with polarization parallel as well as orthogonal to the external
electric field in the leading order in the parameter , which has
been recently found by other methods. For the orthogonal polarization we also
find a new contribution to the rate, which is leading in the ratio of the
photon energy to the electron mass . We also reproduce by a purely
geometrical calculation the exponential factor in the probability of the
stimulated pair creation at arbitrary energy of the photon.Comment: 16 pages, 4 figure
Parity violation in hot QCD: how to detect it
In a recent paper (arXive:hep-ph/0406125) entitled {\em Parity violation in
hot QCD: why it can happen, and how to look for it}, D. Kharzeev argues for the
possibility of P- and/or CP- violation effects in heavy-ion collisions, the
effects that can manifest themselves via asymmetry in production
with respect to the direction of the system angular momentum. Here we present
an experimental observable that can be used to detect and measure the effects.Comment: 2 pages, no figure
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