347 research outputs found
Stability of the trapped nonconservative Gross-Pitaevskii equation with attractive two-body interaction
The dynamics of a nonconservative Gross-Pitaevskii equation for trapped
atomic systems with attractive two-body interaction is numerically
investigated, considering wide variations of the nonconservative parameters,
related to atomic feeding and dissipation. We study the possible limitations of
the mean field description for an atomic condensate with attractive two-body
interaction, by defining the parameter regions where stable or unstable
formation can be found. The present study is useful and timely considering the
possibility of large variations of attractive two-body scattering lengths,
which may be feasible in recent experiments.Comment: 6 pages, 5 figures, submitted to Physical Review
About the computation of the signature of surface singularities z^N+g(x,y)=0
In this article we describe our experiences with a parallel
SINGULAR-implementation of the signature of a surface singularity defined by
z^N+g(x,y)=0.Comment: 6 page
Proximity effect at superconducting Sn-Bi2Se3 interface
We have investigated the conductance spectra of Sn-Bi2Se3 interface junctions
down to 250 mK and in different magnetic fields. A number of conductance
anomalies were observed below the superconducting transition temperature of Sn,
including a small gap different from that of Sn, and a zero-bias conductance
peak growing up at lower temperatures. We discussed the possible origins of the
smaller gap and the zero-bias conductance peak. These phenomena support that a
proximity-effect-induced chiral superconducting phase is formed at the
interface between the superconducting Sn and the strong spin-orbit coupling
material Bi2Se3.Comment: 7 pages, 8 figure
Centrality Dependence of the High p_T Charged Hadron Suppression in Au+Au collisions at sqrt(s_NN) = 130 GeV
PHENIX has measured the centrality dependence of charged hadron p_T spectra
from central Au+Au collisions at sqrt(s_NN)=130 GeV. The truncated mean p_T
decreases with centrality for p_T > 2 GeV/c, indicating an apparent reduction
of the contribution from hard scattering to high p_T hadron production. For
central collisions the yield at high p_T is shown to be suppressed compared to
binary nucleon-nucleon collision scaling of p+p data. This suppression is
monotonically increasing with centrality, but most of the change occurs below
30% centrality, i.e. for collisions with less than about 140 participating
nucleons. The observed p_T and centrality dependence is consistent with the
particle production predicted by models including hard scattering and
subsequent energy loss of the scattered partons in the dense matter created in
the collisions.Comment: 7 pages text, LaTeX, 6 figures, 2 tables, 307 authors, resubmitted to
Phys. Lett. B. Revised to address referee concerns. Plain text data tables
for the points plotted in figures for this and previous PHENIX publications
are publicly available at
http://www.phenix.bnl.gov/phenix/WWW/run/phenix/papers.htm
Phenomenological model for the Kbar N --> K Xi reaction
A phenomenological model for the Kbar N --> K Xi reaction is suggested. The
model includes s and u channel exchanges by Lambda, Sigma, Sigma(1385), and
Lambda(1520) and s channel exchanges by above-threshold hyperonic resonances.
Explicit expression for the propagator for a particle with spin 7/2 is
presented. High-mass and high-spin resonances play a significant role in the
process. We deal with the whole set of existing experimental data on the cross
sections and polarizations in the energy range from the threshold to 2.8 GeV in
the center-of-mass system and reach a good agreement with experiments.
Applications of the model to other elementary reactions of Xi production and to
Xi hypernuclear spectroscopy are briefly discussed.Comment: Published version; minor change
Perfil hematolĂłgico e avaliação eletroforĂ©tica das proteĂnas sĂ©ricas de cĂŁes com cinomose
Elliptic Flow of Identified Hadrons in Au+Au Collisions at sqrt(s_NN) = 200 GeV
The anisotropy parameter v_2, the second harmonic of the azimuthal particles
distribution, has been measured with the PHENIX detector in Au+Au collisions at
sqrt(s_NN) = 200 GeV for identified and inclusive charged particles at central
rapidities (|eta| < 0.35) with respect to the reaction plane defined at high
rapidities (|eta| = 3-4). The v_2 for all particles reaches a maximum at
mid-centrality, and increases with p_T up to 2 GeV/c and then saturates or
decreases slightly. Our results depart from hydrodynamically predicted behavior
above 2 GeV/c. A quark coalescence model is also investigated.Comment: 325 authors, 6 pages text, RevTeX, 3 figures, 0 tables. This version
accepted for publication in Phys. Rev. Lett. after minor changes in response
to referee suggestions. Plain text data tables for the points plotted in
figures for this and previous PHENIX publications are publicly available at
http://www.phenix.bnl.gov/papers.htm
Eritrograma, metabolismo do ferro e concentração sĂ©rica de eritropoetina em fĂȘmeas caprinas da raça Saanen nos perĂodos de gestação, parto e pĂłs-parto
The performance of the jet trigger for the ATLAS detector during 2011 data taking
The performance of the jet trigger for the ATLAS detector at the LHC during the 2011 data taking period is described. During 2011 the LHC provided protonâproton collisions with a centre-of-mass energy of 7 TeV and heavy ion collisions with a 2.76 TeV per nucleonânucleon collision energy. The ATLAS trigger is a three level system designed to reduce the rate of events from the 40 MHz nominal maximum bunch crossing rate to the approximate 400 Hz which can be written to offline storage. The ATLAS jet trigger is the primary means for the online selection of events containing jets. Events are accepted by the trigger if they contain one or more jets above some transverse energy threshold. During 2011 data taking the jet trigger was fully efficient for jets with transverse energy above 25 GeV for triggers seeded randomly at Level 1. For triggers which require a jet to be identified at each of the three trigger levels, full efficiency is reached for offline jets with transverse energy above 60 GeV. Jets reconstructed in the final trigger level and corresponding to offline jets with transverse energy greater than 60 GeV, are reconstructed with a resolution in transverse energy with respect to offline jets, of better than 4 % in the central region and better than 2.5 % in the forward direction
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