Journal Article

Measurement of charged-particle spectra in Pb+Pb collisions at √sNN = 2.76 TeV with the ATLAS detector at the LHC

Petteni, M., Walkowiak, W., Fiascaris, M., Cuhadar Donszelmann, T., Grancagnolo, F., Lucotte, A., Zanzi, D., Strom, D. M., Meyer, J-P., Wittig, T., Grohsjean, A., Hines, E., Hasegawa, S., Friedrich, C., Fabbri, L., Giunta, M., Aguilar-Saavedra, J. A., Carminati, L., Cantero, J., Hubaut, F., Hsu, S.-C., Pedro, R., Gregersen, K., Meyer, C., Hengler, C., Abolins, M., Mellado Garcia, B. R., Diaz, M. A., Dudarev, A., Oren, Y., Borissov, G., Kajomovitz, E., Garberson, F., Yang, Y., Beddall, A., De Lorenzi, F., Catmore, J. R., Calafiura, P., Gonzalez-Sevilla, S., Korn, A., Skinnari, L. A., Laplace, S., AbouZeid, O. S., Moser, H. G., Blanchard, J.-B., Kim, H., Schwindling, J., Hessey, N. P., Schaefer, D., Carter, J. R., Golubkov, D., Krüger, H., Blum, W., Butti, P., Oussoren, K. P., Gazis, E. N., Batley, J. R., Vokac, P., Hawkings, R. J., Lee, J. S. H., Ahlen, S. P., Becker, S., Hall, D., Stapnes, S., Levin, D., Yildirim, E., Barlow, N., Zoccoli, A., Schuh, N., Jia, J., Viehhauser, G. H. A., Cameron, D., Wildt, M. A., Veloso, F., Joshi, K. D., Dervan, P., Tashiro, T., Davidek, T., Debenedetti, C., Pizio, C., Korotkov, V. A., Liang, Z., Jon-And, K., Ozcan,

2015

Overview

A bstract Charged-particle spectra obtained in Pb+Pb interactions at s N N = 2.76 TeV and pp interactions at s N N = 2.76 TeV with the ATLAS detector at the LHC are presented, using data with integrated luminosities of 0.15 nb −1 and 4.2 pb −1 , respectively, in a wide transverse momentum (0 . 5 < p T < 150 GeV) and pseudorapidity (| η | < 2) range. For Pb+Pb collisions, the spectra are presented as a function of collision centrality, which is determined by the response of the forward calorimeters located on both sides of the interaction point. The nuclear modification factors R AA and R CP are presented in detail as a function of centrality, p T and η . They show a distinct p T -dependence with a pronounced minimum at about 7 GeV. Above 60 GeV, R AA is consistent with a plateau at a centrality-dependent value, within the uncertainties. The value is 0 . 55 ± 0 . 01(stat . ) ± 0 . 04(syst . ) in the most central collisions. The R AA distribution is consistent with flat | η | dependence over the whole transverse momentum range in all centrality classes.

• Publisher: Springer,Springer Berlin Heidelberg,Springer Berlin
• Subject: Classical and Quantum Gravitation / Elementary Particles / heavy ions / Heavy Ions; QCD; Nuclear and High Energy Physics / Heavy Ions; QCD; Nuclear and High Energy Physics; ATLAS; LHC / High Energy Physics - Experiment / NUCLEAR PHYSICS AND RADIATION PHYSICS / Physics / Physics and Astronomy / PHYSICS OF ELEMENTARY PARTICLES AND FIELDS / QCD / Quantum Field Theories / Quantum Field Theory / Quantum Physics / Regular Article - Experimental Physics / Relativity Theory / String Theory