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F. Videbaek

Publications and source records attributed to F. Videbaek.

11 recordsLinked to original sources
arXiv2009

Overview and Recent Results from BRAHMS

The BRAHMS experiment was designed to measure and characterize in particular the properties of rapidity dependence of particle production in heavy ion collisions. The data-taking is now over, results of several years of analysis have been published and demonstrates several important features of the rapidity dependence, not envisioned from the start of the RHIC program. The bulk properties of the system formed at high rapidity resemble that of systems at lower energies at mid-rapidity when referenced via the baryo-chemical potential. New physics in AA are essentially observed at mid-rapidity including the demonstration that high-\pT suppression is a final state effect. Another key result is that in d+A collisions at forward rapidities where the very low-x region of the nucleus was probed, a strong suppression of pion production was observed consistent with the picture of gluon saturation. The latest results examines the centrality and rapidity dependence of nuclear stopping, the particle production of pions, collective expansion vs. rapidity, and the baryon enhancement at intermediate values of \pT .

nucl-ex↗
arXiv2008

Results from pp at 62.4 GeV and 200 GeV with the BRAHMS experiment

Measurements of elementary pp collisions are an integral component to understand heavy ion collisions. Results for pp collisions at 200 and 62.4 GeV are presented. At both energies NLO pQCD describes pion production well. The measured pion transverse single spin asymmetries are very large at 62.4 GeV and are reasonably well described by models relying on pQCD at transverse momenta larger than 1 GeV/c.

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arXiv2006

Single Spin Asymmetries in the BRAHMS Experiment

The BRAHMS experiment at RHIC has measured the transverse single spin asymmetries in polarized pp induced pion production at RHIC. The results from the RHIC run-5 shows a significant asymmetry for pi+ and pi- at moderate xF. The trend of the data is in agreement with lower energy results while the absolute values are surprisingly large. The pT dependence is approximately inversely propotional to pT in agreement with the pQCD expectations.

nucl-ex↗
arXiv2005

Single Spin Asymmetries in the BRAHMS Experiment

The BRAHMS experiment at RHIC has the capability to measure the transverse spin asymmetries in polarized pp induced pion production at RHIC. The first results from the short run-4 show a signaificant asymmetry for pi-plus and pi-minus at moderate xF. The trend of the data is in agreement with lower energy data while the absolute value are surprisingly large.

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arXiv2005

Stopping and Baryon Transport in Heavy Ion Reactions

In this report I will give an experimental overview on nuclear stopping in hadron collisions, and relate observations to understanding of baryon transport. Baryon number transport is not only evidenced via net-proton distributions but also by the enhancement of strange baryons near mid-rapidity. Although the focus is on high-energy data obtained from pp and heavy ions from RHIC, relevant data from SPS and ISR will be considered. A discussion how the available data at higher energy relates and gives information on baryon junction, quark-diquark breaking will be made.

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arXiv2001

Stopping in Relativistic Heavy Ion Reactions - From SIS to RHIC

The status of stopping in heavy ion reactions is reviewed by comparing available data in pp, pA and AA systems over the energy regime sqrt(s_NN) ~ 2.5 - 130 GeV/c. The data consist of average rapidity losses, anti-proton over proton ratios, and net-baryon values at mid-rapidity. The overall features of nuclear stopping are reasonbly well described by simple extrapolations of pp, and pA collisions to AA

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arXiv1997

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.

physics.ins-det↗
arXiv1995

In-beam Tests of a Ring Imaging Cerenkov Detector With a Multianode Photomultiplier Readout

A ring-imaging Čerenkov counter read out by a 100-channel PMT of active area 10$\times$10 cm$^2$ was operated successfully in a test beam at the BNL AGS with several radiator gases, including the heavy fluorocarbon C$_4$F$_{10}$. Ring radii were measured for electrons, muons, pions and kaons over the particle momentum range from 2 to 12 GeV/$c$, and a best resolution of $σ_r/r = 2.3\%$ was obtained.

hep-ex↗
arXiv1994

Comparison of Experimental Data to the Relativistic Quantum Molecular Dynamics Model For Si+Au Collisions at 14.6 A GeV/c

Predictions from the RQMD model are systematically compared to recently published charged hadron distributions of AGS Experiment 802 for central Si+Au collisions at 14.6$A$ GeV/$c$, taking into account both the experimental trigger condition and acceptance. The main features of the data, including K$^+$ production, can be understood quantitatively to better than 20\% within the framework of the model, although several discrepancies are found, most importantly for the proton spectra.

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