3,806 research outputs found
Strange particle production in a single-freeze-out model
The transverse-momentum spectra and elliptic flow of strange particles are
calculated in the framework of the single-freeze-out model and compared with
the recent RHIC data. An overall very good agreement between the model
predictions and the data is obtained.Comment: talk presented by WF during the VIIIth Int. Conf. on Strangeness in
Quark Matter, Cape Town, Sept. 15-20, 200
Title: Quadrupole collective inertia in nuclear fission: cranking approximation
Collective mass tensor derived from the cranking approximation to the
adiabatic time-dependent Hartree-Fock-Bogoliubov (ATDHFB) approach is compared
with that obtained in the Gaussian Overlap Approximation (GOA) to the generator
coordinate method. Illustrative calculations are carried out for
one-dimensional quadrupole fission pathways in 256Fm. It is shown that the
collective mass exhibits strong variations with the quadrupole collective
coordinate. These variations are related to the changes in the intrinsic shell
structure. The differences between collective inertia obtained in cranking and
perturbative cranking approximations to ATDHFB, and within GOA, are discussed.Comment: 9 pages, RevTeX, 4 figure
Collective inertia and fission barriers within the Skyrme-Hartree-Fock theory
Spontaneous fission barriers, quadrupole inertia, and zero-point
quadrupole-energy corrections are calculated for 252,256,258Fm in the framework
of the self-consistent Skyrme-Hartree-Fock+BCS theory. Two ways of computing
dynamical inertia are employed: the Gaussian Overlap Approximation to the
Generator Coordinate Method and cranking ansatz. The Skyrme results are
compared with those of the Gogny-Hartree-Fock-Bogolyubov model.Comment: 9 pages, 6 figures, missing factor of 2 found, figures corrected, to
be published in International Journal of Modern Physics
Nuclear Periphery in Mean-Field Models
The halo factor is one of the experimental data which describes a
distribution of neutrons in nuclear periphery. In the presented paper we use
Skyrme-Hartree (SH) and the Relativistic Mean Field (RMF) models and we
calculate the neutron excess factor defined in the paper which
differs slightly from halo factor . The results of the
calculations are compared to the measured data.Comment: Proceedings of the Xth Nuclear Physics Workshop, Maria and Pierre
Curie, Kazimierz Dolny, Poland, Sept 24-28, 2003; LaTex, 4 pages, 3 figure
Multichannel operation of an integrated acousto-optic wavelength routing switch for WDM systems
Polarization independent acousto-optic tunable filters (PIAOTF's) can operate as transparent wavelength-selective crossconnects to route signals in wavelength division multiplexed optical networks. In this paper, a new low power PIAOTF is characterized as a switch in multiwavelength operation, using four equally spaced lightwave signals with wavelengths between 1546 nm and 1558 nm. Interchannel interference due to sidelobe excitation is lower than -11 dB for single wavelength switching and is equal to -6 dB in the extreme case of simultaneous switching of all wavelength channels. Sources of interport and interchannel crosstalk for single and multiple wavelength switching are identified
J08069+1527: A newly discovered high amplitude, hybrid subdwarf B pulsator
We present our discovery of a new hybrid pulsating subdwarf B star,
J08069+1527. The effective temperature and surface gravity of 28,500400\,K
and 5.370.04\,dex, respectively, place this object inside the instability
strip and also among other pulsating hot subdwarfs of a hybrid nature, right
next to another fascinating star: Balloon\,090100001. From this proximity, we
anticipated this star could pulsate in both high and low frequency modes.
Indeed, our analysis of photometric data confirmed our prediction. We detected
two peaks in the high frequency region and two other peaks at low frequencies.
In addition, the amplitude of the dominant mode is very high and comparable to
the dominant peaks in other hybrid subdwarf B stars. Since this star is bright,
we performed time-series low resolution spectroscopy. Despite a low
signal-to-noise (S/N) ratio, we were able to detect the main peak from these
data. All our results strongly indicate that J08069+1527 is a high amplitude
pulsating hot subdwarf B star of hybrid nature. By analogy to the other
pulsating sdB star, we judge that the dominant mode we detected here has radial
nature. Future stellar modeling should provide us with quite good constrains as
p- and g-modes presented in this star are driven in different parts of its
interior.Comment: 7 pages, 10 figures, accepted for publication in MNRA
Balance functions revisited
The idea of glue clusters, i.e. short-range correlations in the quark-gluon
plasma close to freeze-out, is used to estimate the width of balance functions
in momentum space. A good agreement is found with the recent measurements of
STAR collaboration for central collisions
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