The ALICE experiment is designed to study the hot and dense medium, the quark-gluon plasma (QGP), produced in ultra-relativistic heavy-ion collisions at the LHC. Measuring the spectrum of hadrons ...produced in high-
scattering processes in these collisions provides the possibility to explore one of the most spectacular effects – parton energy loss in QGP. By studying several observables with high-energy light-flavour, heavy-flavour hadrons, and jets in
pp
,
p
–Pb and Pb–Pb collision systems, the properties of hot QCD matter can be explored in detail. In these proceedings we present an overview of recent ALICE results on high-
hadron and jet production in
pp
,
p
–Pb and Pb–Pb collisions at LHC energies.
We review ALICE results on direct photon production in pp, pA and AA collisions and compare them to predictions of NLO pQCD calculations, hydrodynamic, and transport models. In pp and pA collisions ...the measured direct photon yield is consistent with NLO pQCD calculations, scaled with the number of binary collisions. In Pb-Pb collisions an additional direct photon contribution is observed at low pT < 4 GeV/c which can be interpreted as a thermal direct photon contribution. The measured yield is larger than predictions of hydrodynamic models, but still consistent with them within uncertainties. The elliptic collective flow of direct photons was measured in central and mid-central Pb-Pb collisions and compared with hydrodynamic model predictions.
We present spectra of π0,η and ω mesons in pp collisions and π0 mesons in Pb–Pb collisions measured with ALICE at LHC energies. The π0 and η mesons are reconstructed via their two-photon decays by ...two complementary methods, using the electromagnetic calorimeters and photon conversion technique; both measurements show perfect agreement. We measure the nuclear modification factor (RAA) of π0 production in Pb–Pb collisions at different collision centralities and compare with lower energy results and theoretical predictions.
We review recent ALICE results on direct photon production in pp, p–Pb and Pb–Pb collisions at LHC energies. In light systems, pp and p–Pb, no signal of direct photons at low
p
T
< 3-5 GeV/c is ...observed within uncertainties, while at high pT our measurements are consistent with NLO pQCD calculations. In central and mid-central Pb–Pb collisions a thermal photon contribution is observed at low
p
T
< 3 - 4 GeV/c with slopes T
eff
= (304 ± 11
stat
± 40
syst
) MeV and (407 ± 61
stat
± 96
syst
) MeV respectively. A collective elliptic flow of direct photons is measured and appeared to be close to the decay photon flow.
We present predictions of direct photon spectrum, rapidity distribution and collective flow in Au‒Au collisions at center of mass energies of 5 and 11 GeV which are anticipated at the future NICA ...facility. The calculations are based on the UrQMD package in the hybrid mode used for description of the evolution of the hot matter created in the collision. The direct photon yield is compared to the yield of neutral pions and decay photons, and the feasibility of these measurements is discussed.
The BM@N spectrometer at the NICA accelerator complex Afanasiev, S.; Aleksandrov, E.; Aleksandrov, I. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
August 2024, 2024-08-00, Letnik:
1065
Journal Article
Recenzirano
BM@N (Baryonic Matter at Nuclotron) is the first experiment operating and taking data at the Nuclotron/NICA ion-accelerating complex. The aim of the BM@N experiment is to study interactions of ...relativistic heavy-ion beams with fixed targets. We present a technical description of the BM@N spectrometer including all its subsystems.
The sPHENIX experiment at RHIC will collect high statistics proton-proton, proton-nucleus and nucleus-nucleus data, starting in the early 2020's. The sPHENIX capabilities enable state-of-the-art ...studies of jet modification, upsilon suppression and open heavy flavor production to probe the microscopic nature of the strongly-coupled Quark Gluon Plasma, and will allow a broad range of cold QCD studies. The sPHENIX detector will provide precision vertexing, tracking and electromagnetic and hadronic calorimetry in the central pseudorapidity region |η| < 1.1, with full azimuth coverage, at the full RHIC collision rate, delivering unprecedented data sets for hard probe tomography measurements at RHIC. In this talk, we will present a brief overview of the sPHENIX detector design with emphasis on calorimetry. The novel design of the sPHENIX calorimeters includes a tungsten/scintillating fiber electromagnetic calorimeter and two steel/scintillating tile hadronic calorimeter sections. The calorimeter has been optimized for upsilon and jet measurements in the high multiplicity environment of heavy-ion collisions. The design has been simulated in detail using GEANT4, and the simulations have extensively vetted against results obtained from the T-1044 test beam facility at FNAL. Both simulation data and test beam data, and the resulting jet physics performance, will be presented in this talk.
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