Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userHighlights from the NA60 experiment
125
0
0.0
(
0
)
Authors
A. Ferretti
Ask ChatGPT about the research
No Arabic abstract
The NA60 experiment is a fixed-target experiment at the CERN SPS. It has measured the dimuon yield in Indium--Indium collisions with an In beam of 158 AGeV/c and in p-A collisions with a proton beam of 400 and 158 AGeV/c. The results allow to address three important physics topics, namely the study of the rho spectral function in nuclear collisions, the clarification of the origin of the dimuon excess measured by NA50 in the intermediate mass range, and the J/psi suppression pattern in a collision system different from Pb-Pb. An overview of these results will be given in this paper.
rate research
Read More
NA60 measured dimuon production in p-A and In-In collisions at the CERN SPS. This paper presents a high statistics measurement of $phi$ meson production in In-In collisions at 158 AGeV. Both the transverse momentum, rapidity, decay angular distributions and the absolute yield were measured as a function of centrality. The results are compared to previous measurements in order to shed light on the long standing $phi$ puzzle. In addition, highlights on $eta$ meson production and on the dimuon excess below the J/$psi$ mass are presented.
A new heavy-ion experiment on fixed target, NA60+, has been proposed at the CERN SPS for data taking in the next years. Its main goals will be focused on precision studies of thermal dimuons, heavy quark and strangeness production in Pb-Pb collisions at center-of-mass energies ranging from 5 to 17 GeV, which will provide a unique opportunity to investigate the region of the QCD phase diagram at high baryochemical potential ($mu_B sim 200-400$~MeV). The key points of the NA60+ very broad and ambitious physics program will be described.
Since 1986, several heavy ion experiments have studied some signatures of the formation of the quark-gluon plasma and a few exciting results have been found. However, some important questions are still unanswered and require new measurements. The NA60 experiment, with a new detector concept that vastly improves dimuon detection in proton-nucleus and heavy-ion collisions, studies several of those open questions, including the production of open charm. This paper presents the experiment and some first results from data collected in 2002.
The NA60 experiment has measured the production of muon pairs and of charged particles in In+In collisions at a beam energy of 158 AGeV. For invariant dimuon masses below the phi the space-time averaged rho spectral function was isolated by a novel procedure. It shows a strong broadening but essentially no shift in mass. The production of J/psi was measured as a function of the collision centrality. As in previous experiments studying Pb+Pb collisions an anomalous supression is observed, setting in at approximately 90 participant nucleons. Using the charged particles the reaction plane was reconstructed. The elliptic flow of charged particles increases with pt showing a saturation for pt > 2GeV/c. For the first time azimuthal distributions for J/psi are shown.
Highlights of news from Brookhaven National Laboratory (BNL) and results from the Relativistic Heavy Ion Collider (RHIC) in the period July 2013-June 2014 are presented. It was a busy year for news, most notably a U. S. Government shutdown for 16 days beginning October 1, 2013 due to the lack of an approved budget for FY2014. Even with this unusual government activity, the $sqrt{s_{NN}}=200$ GeV Au+Au Run14 at RHIC was the best ever with integrated luminosity exceeding the sum of all previous runs. Additionally there was a brief He$^3$+Au run to continue the study of collective flow in small systems which was reinforced by new results presented on identified particle flow in d+Au. The other scientific highlights are also mostly concerned with ``soft (low $p_T$) physics complemented by the first preliminary results of reconstructed jets from hard-scattered partons in Au+Au collisions at RHIC . The measurements of transverse energy ($E_T$) spectra in p-p, d+Au and Au+Au collisions, which demonstrated last year that constituent quarks are the fundamental elements of particle production in all 3 systems, led to the conclusion that the two-component ansatz which has been used to represent $E_T$ distributions as a function of centrality is simply a proxy for the number of constituent quark participants as well as to an explanation of the surprising elliptical flow results from U+U collisions. An extensive discussion of the latest measurements in Au+Au of net-charge and net-proton distributions represented by Cumulants of the distributions and plans for a Beam Energy Scan at RHIC to look for a QCD critical point is presented and compared to the claim implied by a press release during the 2011 ISSP.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
