Particle production at RHIC energies

R. Debbe

doi:10.1063/1.1664329

Home/Archive/arXiv

arXiv · nucl-ex/0308004

Particle production at RHIC energies

R. Debbe

View original source ↗Read source document ↗Export metadata ↓

Abstract

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.

Explore related subjects

nucl-ex

Keep this discovery

Explore connections, maps & timelines

BibTeX RIS

R. Debbe. 2003-08-06. Particle production at RHIC energies. https://doi.org/10.1063/1.1664329

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

arXiv2026

Modernization in processing and dissemination of experimental cross section data in EXFOR

The EXFOR library is a nearly complete database for experimental radionuclide production cross sections for light charged-particle induced reactions, and retrieval of the experimental cross sections in EXFOR is the first step in determination of the best estimate of the radionuclide production cross section. The EXFOR format was designed with 80-column punched cards as the recording media, but the format is still preferred for compilation and exchange of the nuclear reaction data. The format is suitable for reading and processing by EXFOR compilers, but it is not a good choice for reading by EXFOR users with modern computer languages such as Python. We have recently attempted to lower the barrier for modern software engineers to access the information stored in the EXFOR by developing tools converting an EXFOR file to (1) the HTML format for human reading (X4IVEW), and (2) the CX4 (Compact EXFOR) format for tabulation and plotting (X4TOCX). This article introduces X4VIEW and a preliminary version of X4TOCX with the radionuclide production cross section as an example.

nucl-ex↗

arXiv2026

Probing jet quenching via the correlation of groomed jet substructure observables in Pb$-$Pb and pp collisions

A measurement of the correlation between the splitting angle $θ_{\rm g}$ and the momentum-sharing fraction $z_{\rm g}$ of the first hard splitting in a parton shower in pp collisions and 0$-$10% central Pb$-$Pb collisions at $\sqrt{s_{\rm NN}}$ = 5 TeV with the ALICE detector is reported. Charged-particle jets are reconstructed using the anti-$k_{\rm T}$ algorithm with a jet resolution parameter $R$ = 0.2, in the transverse-momentum range $60 \leq p_{\rm T,ch\;jet} < 80$ GeV/$c$. The Soft Drop grooming algorithm is used to identify the first splitting in the parton shower. Jets observed in Pb$-$Pb collisions are narrower than in pp collisions. This effect is more pronounced for balanced than for unbalanced jets. No significant modification of the momentum-sharing fraction is observed for jets with small opening angles. In contrast, there is a hint that jets with a large opening angle may be less balanced in transverse momentum in Pb$-$Pb collisions compared to pp collisions. The correlations between $θ_{\rm g}$ and $z_{\rm g}$ are well described in pp collisions by PYTHIA 8 and POWHEG while HERWIG shows too few jets with large opening angle. In Pb$-$Pb collisions the measurement is compared to a variety of models. The measurement is insensitive to the different implementations of medium response. Inclusion of elastic scatterings, as implemented in the HYBRID model is preferred to describe the unbalanced jets with large $θ_{\rm g}$ in Pb$-$Pb collisions. The balanced jets, however, are less sensitive to elastic scatterings.

nucl-ex↗

arXiv2026

Observation of nuclear suppression in coherent $Υ$(1S) photoproduction off heavy nuclei at the LHC

The first measurement of coherent $Υ$(1S) meson photoproduction off heavy nuclei is performed using ultraperipheral lead-lead collisions collected by the CMS experiment at a nucleon-nucleon center-of-mass energy of 5.02 TeV. The nuclear gluonic structure is probed at a nucleon momentum fraction of order $x$ $\sim$ 10$^{-3}$, determined by the kinematics of the process. Owing to the large $Υ$(1S) mass, the measurement reaches the highest scale accessible so far through coherent vector-meson photoproduction, $μ^2$ = 22.4 GeV$^2$, where nonlinear quantum chromodynamics effects are expected to be minimal. In the $Υ$(1S) rapidity range $\lvert y\rvert$ $\lt$ 1, the ratio of the measured photoproduction cross section to a baseline model prediction that neglects nuclear effects is $S_{Υ\text{(1S)}}$ = 0.25 $\pm$ 0.06 (stat) $\pm$ 0.02 (syst), thereby demonstrating nuclear suppression in this process. Expressed in terms of a nuclear gluon suppression factor, the result yields $R_\text{g}^\text{Pb}$($x$ $\approx$ 10$^{-3}$, $μ^2$ = 22.4 GeV$^2$) = 0.55 $\pm$ 0.12 (stat) $\pm$ 0.02 (syst). The measured $R_\text{g}^\text{Pb}$ is only slightly larger than the values previously reported for coherent $ϕ$ photoproduction, despite the probed $μ^2$ differing by approximately two orders of magnitude.

nucl-ex↗