arXiv subjects

M. Dzelalija

Publications and source records attributed to M. Dzelalija.

6 recordsLinked to original sources

arXiv2011

Systematics of azimuthal asymmetries in heavy ion collisions in the 1 A GeV regime

Using the large acceptance apparatus FOPI, we study central and semi-central collisions in the reactions (energies in A GeV are given in parentheses): 40Ca+40Ca (0.4, 0.6, 0.8, 1.0, 1.5, 1.93), 58Ni+58Ni (0.15, 0.25, 0.4), 96Ru+96Ru (0.4, 1.0, 1.5), 96Zr+96Zr (0.4, 1.0, 1.5), 129Xe+CsI (0.15, 0.25, 0.4), 197Au+197Au (0.09, 0.12, 0.15, 0.25, 0.4, 0.6, 0.8, 1.0, 1.2, 1.5). The observables include directed and elliptic flow. The data are compared to earlier data where possible and to transport model simulations. A stiff nuclear equation of state is found to be incompatible with the data. Evidence for extra-repulsion of neutrons in compressed asymmetric matter is found.

nucl-ex↗

arXiv2010

Systematics of central heavy ion collisions in the 1A GeV regime

Using the large acceptance apparatus FOPI, we study central collisions in the reactions (energies in A GeV are given in parentheses): 40Ca+40Ca (0.4, 0.6, 0.8, 1.0, 1.5, 1.93), 58Ni+58Ni (0.15, 0.25, 0.4), 96Ru+96Ru (0.4, 1.0, 1.5), 96Zr+96Zr (0.4, 1.0, 1.5), 129Xe+CsI (0.15, 0.25, 0.4), 197Au+197Au (0.09, 0.12, 0.15, 0.25, 0.4, 0.6, 0.8, 1.0, 1.2, 1.5). The observables include cluster multiplicities, longitudinal and transverse rapidity distributions and stopping, and radial flow. The data are compared to earlier data where possible and to transport model simulations.

nucl-ex↗

arXiv2009

Radiation hardness qualification of PbWO4 scintillation crystals for the CMS Electromagnetic Calorimeter

Ensuring the radiation hardness of PbWO4 crystals was one of the main priorities during the construction of the electromagnetic calorimeter of the CMS experiment at CERN. The production on an industrial scale of radiation hard crystals and their certification over a period of several years represented a difficult challenge both for CMS and for the crystal suppliers. The present article reviews the related scientific and technological problems encountered.

physics.ins-det↗

arXiv2009

Measurement of the in-medium K0 inclusive cross section in pi- -induced reactions at 1.15 GeV/c

The K0 meson production by pi- mesons of 1.15 GeV/c momentum on C, Al, Cu, Sn and Pb nuclear targets was measured with the FOPI spectrometer at the SIS accelerator of GSI. Inclusive production cross-sections and the momentum distributions of K0 mesons are compared to scaled elementary production cross-sections and to predictions of theoretical models describing the in-medium production of kaons. The data represent a new reference for those models, which are widely used for interpretation of the strangeness-production in heavy-ion collisions. The presented results demonstrate the sensitivity of the kaon production to the reaction amplitudes inside nuclei and point to the existence of a repulsive KN-potential of 20+-5 MeV at normal nuclear matter density.

nucl-ex↗

arXiv2004

Azimuthal dependence of collective expansion for symmetric heavy ion collisions

Detailed studies of the azimuthal dependence of the mean fragment and flow energies in the Au+Au and Xe+CsI systems are reported as a function of incident energy and centrality. Comparisons between data and model calculations show that the flow energy values along different azimuthal directions could be viewed as snapshots of the fireball expansion with different exposure times. For the same number of participating nucleons more transversally elongated participant shapes from the heavier system produce less collective transverse energy. Good agreement with BUU calculations is obtained for a soft nuclear equation of state.

nucl-ex↗

arXiv1998

Discovery potential for supersymmetry in CMS

This work summarizes and puts in an overall perspective studies done within CMS concerning the discovery potential for squarks and gluinos, sleptons, charginos and neutralinos, SUSY dark matter, lightest Higgs, sparticle mass determination methods and the detector design optimisation in view of SUSY searches. It represents the status of our understanding of these subjects as of Summer 1997. As a benchmark model we used the minimal supergravity-inspired super- symmetric standard model (mSUGRA) with a stable LSP. Discovery of SUSY at the LHC should be relatively straightforward. It may occur through the observation of a large excesses of events in missing E_T + jets, or with one or more isolated leptons. An excess of trilepton events or of isolated dileptons with E_T^miss, exhibiting a characteristic signature in the l^+l^- invariant mass distribution could also be the first manifestation of SUSY production. Squark and gluino production may represent a copious source of Higgs bosons through cascade decays. The lightest SUSY Higgs h->bbbar may be reconstructed with a signal/background ratio of order 1. The lightest supersymmetric particle of SUSY models with conserved R-parity represents a very good candidate for the cosmological dark matter. The region of parameter space where this is true is well-covered by our searches, at least for tan(beta)=2. If supersymmetry exists at electroweak scale it could hardly escape detection in CMS, and the study of supersymmetry will form a central part of our physics program.

hep-ph↗