Photon and [pi]0 Production in 197Au+197Au Collisions at [square Root]NN
Author: Ian Jeffrey Johnson
Publisher:
Published: 2002
Total Pages: 210
ISBN-13:
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Author: Ian Jeffrey Johnson
Publisher:
Published: 2002
Total Pages: 210
ISBN-13:
DOWNLOAD EBOOKAuthor: Ian Jeffrey Johnson
Publisher:
Published: 2002
Total Pages: 234
ISBN-13:
DOWNLOAD EBOOKAuthor:
Publisher:
Published: 2002
Total Pages: 96
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DOWNLOAD EBOOKInclusive transverse momentum spectra of photons and [pi]°s at mid-rapidity are studied as a function of collision centrality for 197Au+ 197Au collisions at √s{sub NN} = 130 GeV. Photon pair conversions have been reconstructed from charged tracks measured by the main Time Project Chamber of the STAR experiment at the RHIC heavy ion facility. The transverse momentum resolution of photons with this method is estimated to be [Delta]p{sub t}/p{sub t} = 2% at 0.125 GeV/c and 5% at 2.5 GeV/c. Photon spectra were measured up to a transverse momentum of 2.4 GeV/c between ± 0.5 units of rapidity. The dominant photon production mechanism, the [pi]° → [gamma][gamma] decay, was measured between 0.25-2.5 GeV/c and ± 1 units of rapidity. Spectra are reported for the top 11%, 11-34% and 34-85% centrality classes. It was observed that in mid-central and central collisions the relative contribution of the [pi]° → [gamma][gamma] decay to the inclusive photon spectrum decreases above a transverse momentum of 1.65 GeV/c. In central collisions the magnitude of the decrease from p{sub t} = 1.65 GeV/c to 2.4 GeV/c is 20%. It is unlikely that contributions from other [pi]° decay channels and other particle decays fully explain this decrease. The centrality dependence on the shapes of the [pi]° spectra was analyzed with Boltmann and Bose-Einstein functions. In the transverse momentum windows of the spectra, the extracted temperatures are near 0.295 GeV. These temperatures are substantially higher than those extracted from [pi]{sup {+-}} spectra in a lower range of transverse momentum. This is an indication that the shapes of the pion spectra deviate from purely exponential shapes.
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Publisher:
Published: 2002
Total Pages: 96
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DOWNLOAD EBOOKInclusive transverse momentum spectra of photons and ?0s at mid-rapidity are studied as a function of collision centrality for 197Au+ 197Au collisions at √sNN = 130 GeV. Photon pair conversions have been reconstructed from charged tracks measured by the main Time Project Chamber of the STAR experiment at the RHIC heavy ion facility. The transverse momentum resolution of photons with this method is estimated to be ?pt/pt = 2% at 0.125 GeV/c and 5% at 2.5 GeV/c. Photon spectra were measured up to a transverse momentum of 2.4 GeV/c between ± 0.5 units of rapidity. The dominant photon production mechanism, the ?0 → ?? decay, was measured between 0.25-2.5 GeV/c and ± 1 units of rapidity. Spectra are reported for the top 11%, 11-34% and 34-85% centrality classes. It was observed that in mid-central and central collisions the relative contribution of the ?0 → ?? decay to the inclusive photon spectrum decreases above a transverse momentum of 1.65 GeV/c. In central collisions the magnitude of the decrease from pt = 1.65 GeV/c to 2.4 GeV/c is 20%. It is unlikely that contributions from other ?0 decay channels and other particle decays fully explain this decrease. The centrality dependence on the shapes of the ?0 spectra was analyzed with Boltmann and Bose-Einstein functions. In the transverse momentum windows of the spectra, the extracted temperatures are near 0.295 GeV. These temperatures are substantially higher than those extracted from ?± spectra in a lower range of transverse momentum. This is an indication that the shapes of the pion spectra deviate from purely exponential shapes.
Author: Thomas Gordon Carter
Publisher:
Published: 1990
Total Pages: 524
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Published: 1994
Total Pages: 3
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DOWNLOAD EBOOKThe authors present preliminary results of a measurement of inclusive photon-charm production in {anti p}p collisions. Using data collected by the CDF experiment during the 1992--1993 Tevatron collider run, the authors have measured the inclusive photon-muon cross section, and estimated the decay-in-flight and punchthrough backgrounds. They compare the measured photon-muon cross section and photon E{sub T} spectrum to Pythia predictions for the charm Compton contribution.
Author: Charles A. Loomis
Publisher:
Published: 1992
Total Pages: 292
ISBN-13:
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