Observation of direct photons in central 158A GeV Pb-208+Pb-208 collisions

Authors
Aggarwal, MM Agnihotri, A Ahammed, Z Angelis, ALS Antonenko, V Arefiev, V Astakhov, V Avdeitchikov, V Awes, TC Baba, PVKS Badyal, SK Barlag, C Bathe, S Batiounia, B Bernier, T Bhalla, KB Bhatia, VS Blume, C Bock, R Bohne, EM Borocz, Z Bucher, D Buijs, A Busching, H Carlen, L Chalyshev, V Chattopadhyay, S Cherbatchev, R Chujo, T Claussen, A Das, AC Decowski, MP Delagrange, H Djordjadze, V Donni, P Doubovik, I Dutt, S Majumdar, MRD El Chenawi, K Eliseev, S Enosawa, K Foka, P Fokin, S Ganti, MS Garpman, S Gavrishchuk, O Geurts, FJM Ghosh, TK Glasow, R Gupta, SK Guskov, B Gustafsson, HA Gutbrod, HH Higuchi, R Hrivnacova, I Ippolitov, M Kalechofsky, H Kamermans, R Kampert, KH Karadjev, K Karpio, K Kato, S Kees, S Klein-Bosing, C Knoche, S Kolb, BW Kosarev, I Koutcheryaev, I Krumpel, T Kugler, A Kulinich, P Kurata, M Kurita, K Kuzmin, N Langbein, I Lebedev, A Lee, YY Lohner, H Luquin, L Mahapatra, DP Manko, V Martin, M Martinez, G Maximov, A Mgebrichvili, G Miake, Y Mir, MF Mishra, GC Miyamoto, Y Mohanty, B Mora, MJ Morrison, D Mukhopadhyay, DS Naef, H Nandi, BK Nayak, SK Nayak, TK Neumaier, S Nianine, A Nikitine, V Nikolaev, S Nilsson, P Nishimura, S Nomokonov, P Nystrand, J Obenshain, FE Oskarsson, A Otterlund, I Pachr, M Pavliouk, S Peitzmann, T Petracek, V Pinganaud, W Plasil, F von Poblotzki, U Purschke, ML Rak, J Raniwala, R Raniwala, S Ramamurthy, VS Rao, NK Retiere, F Reygers, K Roland, G Rosselet, L Roufanov, I Roy, C Rubio, JM Sako, H Sambyal, SS Santo, R Sato, S Schlagheck, H Schmidt, HR Schutz, Y Shabratova, G Shah, TH Sibiriak, I Siemiarczuk, T Silvermyr, D Sinha, BC Slavine, N Soderstrom, K Solomey, N Good, G Sorensen, SP Stankus, P Stefanek, G Steinberg, P Stenlund, E Stuken, D Sumbera, M Svensson, T Trivedi, MD Tsvetkov, A Tykarski, L Urbahn, J von der Pijll, EC von Eijndhoven, N von Nieuwenhuizen, GJ Vinogradov, A Viyogi, YP Vodopianov, A Voros, S Wyslouch, B Yagi, K Yokota, Y Young, GR
Citation
Mm. Aggarwal et al., Observation of direct photons in central 158A GeV Pb-208+Pb-208 collisions, PHYS REV L, 85(17), 2000, pp. 3595-3599
Citations number
26
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Physics
Journal title
PHYSICAL REVIEW LETTERS
ISSN journal
0031-9007 → ACNP
Volume
85
Issue
17
Year of publication
2000
Pages
3595 - 3599
Database
ISI
SICI code
0031-9007(20001023)85:17<3595:OODPIC>2.0.ZU;2-7
Abstract
A measurement of direct photon production in Pb-208 + Pb-208 collisions at 158A GeV has been carried out in the CERN WA98 experiment. The invariant yi eld of direct photons in central collisions is extracted as a function of t ransverse momentum in the interval 0.5 < p(T) < 4 GeV/c. A significant dire ct photon signal, compared to statistical and systematical errors, is seen at p(T) > 1.5 GeV/c. The result constitutes the first observation of direct photons in ultrarelativistic heavy-ion collisions. It could be significant for diagnosis;of quark-gluon-plasma formation.