Download or read book Multi pion Interferometry in Ultrarelativistic Pb Pb Collisions at the CERN SPS written by Petra Hummel and published by . This book was released on 1998 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Pion and Kaon Correlations in High Energy Heavy ion Collisions written by and published by . This book was released on 1996 with total page 39 pages. Available in PDF, EPUB and Kindle. Book excerpt: Data analysis is in progress for recent experiments performed by the NA44 collaboration with the first running of 160 A GeV 2°8Pb-induced reactions at the CERN SPS. Identified singles spectra were taken for pions, kaons, protons, deuterons, antiprotons and antideuterons. Two-pion interferometry measurements were made for semi-central-triggered 2°8Pb + Pb collisions. An upgraded multi-particle spectrometer allows high statistics data sets of identified particles to be collected near mid-rapidity. A second series of experiments will be performed in the fall of 1995 with more emphasis on identical kaon interferometry and on the measurement of rare particle spectra and correlations. Modest instrumentation upgrades by TAMU are designed to increase the trigger function for better impact parameter selection and improved collection efficiency of valid events. An effort to achieve the highest degree of projectile-target stopping is outlined and it is argued that an excitation function on the SPS is needed to better understand reaction mechanisms. Analysis of experimental results is in the final stages at LBL in the EOS collaboration for two-pion interferometry in the 1.2 A GeV Au+Au reaction, taken with full event characterization. 35 refs., 15 figs., 5 tabs.
Download or read book Pion Correlations and Calorimeter Design for High Energy Heavy Ion Collisions Progress Report written by and published by . This book was released on 1997 with total page 43 pages. Available in PDF, EPUB and Kindle. Book excerpt: Data analysis is in progress for recent experiments performed by the NA44 collaboration with the first running of 160 A GeV 2°8Pb-induced reactions at the CERN SPS. Identified singles spectra were taken for pions, kaons, protons, deuterons, antiprotons and antideuterons. Two-pion interferometry measurements were made for semi-central-triggered 2°8Pb + Pb collisions. An updated multi-particle spectrometer allows high statistics data sets of identified particles to be collected near mid-rapidity. A second series of experiments will be performed in the fall of 1995 with more emphasis on identical kaon interferometry and on the measurement of rare particle spectra and correlations. Modest instrumentation upgrades by TAMU are designed to increase the trigger function for better impact parameter selection and improved collection efficiency of valid events. An effort to achieve the highest degree of projectile-target stopping is outlined and it is argued that an excitation function on the SPS is needed to better understand reaction mechanisms. Analysis of experimental results is in the final stages at LBL in the EOS collaboration for two-pion interferometry in the 1.2 A GeV Au + Au reaction, taken with full event characterization.
Download or read book Pion Interferometry in E814 Toward Equilibrium at the AGS written by and published by . This book was released on 1994 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: The ultimate goal of ultra-relativistic heavy-ion program at the BNL AGS and CERN SPS is to study highly excited nuclear matter and the transition from hadronic matter to quark gluon plasma. In the QGP state, quarks and gluons are no longer confined but they move freely in a fairly large volume. According to their knowledge, the de-confined state can be approached via either compression or heating of nuclear matter in heavy-ion collisions. At AGS energies, the most relevant process is believed to be compression. However, before the authors try to identify any exotic events such as, for example QGP phase transition or chiral symmetry restoration, they have to answer the following questions: (1) Were the densities(due to the compression) high enough? (2) Was the high density region large enough? (3) Was the system thermalized? The authors report recent pion interferometry results from AGS experiment E814. By comparing to the results of RQMD calculations, a freeze-out size R{sub rms} = 8.3 fm is found in Si + Pb central collisions. A consistent thermal equilibration picture is established by comparing experimental data with the results of both hydrodynamic and cascade model calculations.
Download or read book Pion Interferometry in Sup 28Si Pb Central Collisions written by and published by . This book was released on 1994 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book HIGH Energy Pb Pb Collisions Viewed by Pion Interferometry Extras written by J. BOISSEVAIN and published by . This book was released on 1998 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book written by and published by . This book was released on 1979 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Pion Interferometry in 28Si Pb Central Collisions written by and published by . This book was released on 1994 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: Two-pion correlation functions have been studied using the E814 apparatus in 14.6 A·GeV/c 28Si + Pb central collisions. Results of the correlation functions for pions from the RQMD event generator are compared to the data and show that a source with RMS radius of 8.3 fm is compartable with the experimental data.
Download or read book Pion Interferometry of Ultra relativistic Hadronic Collisions written by and published by . This book was released on 1986 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Pion interferometry of ultra-relativistic hadronic collisions is described in the context of the inside-outside cascade model using a current ensemble method capable of describing an arbitrary distribution of pion sources with an arbitrary velocity distribution. The results are quite distinct from the usual Gaussian and Kopylov parameterizations. Extraction of the temperature parameter, effective source lifetime, and transverse size requires a full three-dimensional analysis of the correlation function in terms of the momentum difference. 7 refs., 4 figs.
Download or read book Two Particle Correlations at 40 80 and 158 AGeV Pb Au Collisions written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In this thesis, a centrality dependent study of tow-particle momentum correlations of like-sign pions (HBT interferometry) from Pb-Au collisions at beam energies of 40, 80 and 158 AGeV is presented. The three-dimensional correlation function C_2, depending on the relative momentum components of the particle pair, was parameterized using a three-dimensional Gaussian, modified to consider the final state Coulomb repulsion. The parameterization was done in the Cartesian out-side-long system as proposed by G. Bertsch and S. Pratt. A differential analysis of the HBT radius parameters as a function of the mean transverse pair momentum k_perp allowed to determine transverse geometrical source sizes of about 5.5 fm to 7 fm, increasing with energy and centrality. The mean transverse flow velocity v_perp was found to be of the order 0.5--0.6 c. For the freeze-out time tau_f values between 6 and 8 fm/c were obtained with a duration of particle emission compatible with zero. The beam energy dependence of the HBT radii provide evidence for a universal pion freeze-out condition. The analyzed data have been recorded with the CERES spectrometer at the Super Proton Synchrotron (SPS) accelerator at CERN.
Download or read book Kaon and Pion Interferometry Final Report written by and published by . This book was released on 1998 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: Both NA44 and EOS continue to publish high quality data on relativistic heavy ion collisions. The next leap in energy will be provided by BRAHMS at RHIC. Experiment NA44 has measured particle correlations of [pi]{sup {+-}}, K and protons and single particle distributions of [pi]{sup {+-}}, K{sup {+-}}, p, {anti p}, d and {anti d} for pA, SA and PbPb collisions at 450GeV/c, 200A·GeV and 158A·GeV for the p, S and Pb beams respectively. When the spectra are fitted to an exponential in m{sub T}, the inverse slopes increase as the system gets heavier and with increasing particle mass. For larger systems the baryon density at mid-rapidity increases implying more secondary collisions. These fuel a collective expansion and a boost in transverse momentum proportional to the mass as seen in the data. The EOS collaboration has continued to publish results from their large data set of heavy ion collisions at the BEVALAC. They plan to study the energy dependence of coalescence and flow by comparing results from NA44 and EOS.
Download or read book Physics Briefs written by and published by . This book was released on 1994 with total page 916 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Energy Dependence of Transverse Momentum Fluctuations in Pb Pb Collisions at the CERN Super Proton Synchrotron SPS at 20A to 158A GeV written by and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Results are presented on event-by-event fluctuations of transverse momenta p{sub T} in central Pb+Pb interactions at 20A, 30A, 40A, 80A, and 158A GeV. The analysis was performed for charged particles at forward center-of-mass rapidity (1.1
Download or read book High Energy Physics Index written by and published by . This book was released on 1990 with total page 716 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Two pion Correlation Measurements in 450 GeV c P A Collisions at the CERN SPS written by Akiyoshi Miyabayashi and published by . This book was released on 1995 with total page 105 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Recent Results from Hadronic Observables at the CERN SPS written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Some recent results on Pb+Pb collisions from NA44 and NA49 at the CERN SPS are reviewed and compared to collisions of lighter systems and lower energies. For central collisions: primordial protons show enhanced stopping for Pb+Pb relative to S+S at the same energy, but less stopping than heavy systems at lower energy; yields of negative hadrons, kaons and lambdas scale with the number of participants relative to S+S; and transverse momentum spectra show strong evidence for enhanced radial flow in the heaviest system. For intermediate impact parameters, significant quadrupole deformation of the transverse energy distribution is seen at mid-rapidity. Coulomb effects are seen for central collisions in the ratio of yields[pi][sup -]/[pi][sup+] and unlike-sign two particle correlations.
Download or read book Production in Pb Pb Collisions at 158 GeV c written by and published by . This book was released on 1997 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: Using the NA49 main TPC, the central production of (? + {bar?}) hyperons has been measured in CERN SPS Pb on Pb collisions at 158 GeV/c. The preliminary ({Xi} + {bar {Xi}})/ (? + {bar {Lambda}}) ratio, studied at 2.0
