1,749 research outputs found
The ring imaging Cherenkov detector for the BRAHMS experiment at RHIC
A ring imaging Cherenkov counter, to be read out by four 100-channel PMTs, is
a key element of the BRAHMS experiment. We report here the most recent results
obtained tested at the BNL AGS using several radiator gases, including the
heavy fluorocarbon C4F10. Ring radii were measured for different particles
(pions, muons, and electrons) for momenta ranging from 2 to 12 GeV/c employing
pure C4F10 as radiator.Comment: 3 pages 3 figure
Particle production at RHIC energies
This paper presents recent results from the BRAHMS experiment at RHIC;
including results on particle production in rapidity space extending from y=0
to y ~ 3 and on the transverse momentum distribution of fully identified
charged particles. These results were obtained from the 5% most central Au-Au
collisions recorded during RHIC Run-2 at sqrt{s_{NN}} = 200 GeV.Comment: Four pages, 3 figures to appear in the Proceedings of the CIPANP 2003
conferenc
Rho Meson Diffraction off Au Nuclei
The STAR Ultra Peripheral Collisions program has collected a substantial
sample of mesons and for the first time at RHIC energies it has been
able to extract the distribution of momentum transfer t from diffractive
elastic scattering off the Au ion. The resulting diffraction pattern is
consistent with coherent scattering off a nuclear object the size of the Au
nuclei. Measurements of this nature can offer insights and guidance to the
ongoing preparations for the new electron ion programs.Comment: 8 pages 11 figures, submitted to the proceedings of the 28th Winter
Workshop on Nuclear Dynamic
Charged Particle Production at High Rapidity in p+p Collisions at RHIC
This report describes the recent analysis of identified charged particle
production at high rapidity performed on data collected from p+p collisions at
RHIC (sqrt{s}=200 GeV). The extracted invariant cross-sections compare well to
NLO pQCD calculations. However, a puzzling high yield of protons at high
rapidity and p_T has been found.Comment: 5 pages, four figures. The labels of the x-axis in figure 1 have been
correcte
High Rapidity Physics with the BRAHMS Experiment
We report the study of the nuclear modification factor R_{AuAu} as function
of pT and pseudo-rapidity in Au+Au collisions at top RHIC energy. We find this
quantity almost independent of pseudo-rapidity. We use the pbar/pi- ratio as a
probe of the parton density and the degree of thermalization of the medium
formed by the collision. The pbar/pi- ratio has a clear rapidity dependence.
The combination of these two measurements suggests that the pseudo-rapidity
dependence of the R_{AuAu results from the competing effects of energy loss in
a dense and opaque medium and the modifications of the wave function of the
high energy beams in the initial state.Comment: 5 pages, four figures, to appear in the proceedings of the 9th
Conference on the Intersections of Particle and Nuclear Physics (CIPANP
2006), Puerto Rico, 30 May - 3 June 200
BRAHMS Overview
A brief review of BRAHMS measurements of bulk particle production in RHIC
Au+Au collisions at is presented, together with some
discussion of baryon number transport. Intermediate measurements in
different collision systems (Au+Au, d+Au and p+p) are also discussed in the
context of jet quenching and saturation of the gluon density in Au ions at RHIC
energies. This report also includes preliminary results for identified
particles at forward rapidities in d+Au and Au+Au collisions.Comment: 8 pages 6 figures, Invited plenary talk at 5th International
Conference on Physics and Astrophysics of Quark Gluon Plasma (ICPAQGP 2005),
Salt Lake City, Kolkata, India, 8-12 Feb 200
Recent results from BRAHMS
The BRAHMS collaboration ended its data collection program in 2006. We are
now well advanced in the analysis of a comprehensive set of data that spans
systems ranging in mass from p+p to Au+Au and in energy from to 200 GeV. Our analysis has taken two distinct paths: we explore the
rapidity dependence of intermediate and high-transverse-momentum,
identified-particle production, thus helping to characterize the
strongly-interacting quark-gluon plasma (sQGP) formed at RHIC; we also explore
particle yields at lower transverse momentum to develop a systematic
understanding of bulk particle production at RHIC energies.Comment: 8 pages, 5 figures, presented at the 20th International Conference on
Ultra-Relativistic Nucleus-Nucleus Collisions, "Quark Matter 2008", Jaipur,
India, February 4-10, 200
The effectiveness of asking behaviors among 9-11 year-old children in increasing home availability and children's intake of fruit and vegetables : results from the Squire's Quest II self-regulation game intervention
Background: Home environment has an important influence on children's fruit and vegetable (FV) consumption, but children may in turn also impact their home FV environment, e.g. by asking for FV. The Squire's Quest II serious game intervention aimed to increase asking behaviors to improve home FV availability and children's FV intake. This study's aims were to assess: 1) did asking behaviors at baseline predict home FV availability at baseline (T0) (RQ1); 2) were asking behaviors and home FV availability influenced by the intervention (RQ2); 3) did increases in asking behaviors predict increased home FV availability (RQ3); and 4) did increases in asking behaviors and increases in home FV availability mediate increases in FV intake among children (RQ4)?
Methods: This is a secondary analysis of a study using a randomized controlled trial, with 4 groups (each n = 100 child-parent dyads). All groups were analyzed together for this paper since groups did not vary on components relevant to our analysis. All children and parents (n = 400 dyads) received a self-regulation serious game intervention and parent material. The intervention ran for three months. Measurements were taken at baseline, immediately after intervention and at 3-month follow-up. Asking behavior and home FV availability were measured using questionnaires; child FV intake was measured using 24-h dietary recalls. ANCOVA methods (research question 1), linear mixed-effect models (research question 2), and Structural Equation Modeling (research questions 3 and 4) were used.
Results: Baseline child asking behaviors predicted baseline home FV availability. The intervention increased child asking behaviors and home FV availability. Increases in child asking behaviors, however, did not predict increased home FV availability. Increased child asking behaviors and home FV availability also did not mediate the increases in child FV intake.
Conclusions: Children influence their home FV environment through their asking behaviors, which can be enhanced via a serious game intervention. The obtained increases in asking behavior were, however, insufficient to affect home FV availability or intake. Other factors, such as child preferences, sample characteristics, intervention duration and parental direct involvement may play a role and warrant examination in future research
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