https://doi.org/10.1140/epjc/s10052-018-6013-8
Regular Article - Experimental Physics
Neutral pion and
meson production in p–Pb collisions at
= 5.02 TeV
1
A.I. Alikhanyan National Science Laboratory (Yerevan Physics Institute) Foundation, Yerevan, Armenia
2
Benemérita Universidad Autónoma de Puebla, Puebla, Mexico
3
Bogolyubov Institute for Theoretical Physics, National Academy of Sciences of Ukraine, Kiev, Ukraine
4
Department of Physics and Centre for Astroparticle Physics and Space Science (CAPSS), Bose Institute, Kolkata, India
5
Budker Institute for Nuclear Physics, Novosibirsk, Russia
6
California Polytechnic State University, San Luis Obispo, CA, USA
7
Central China Normal University, Wuhan, China
8
Centre de Calcul de l’IN2P3, Villeurbanne, Lyon, France
9
Centro de Aplicaciones Tecnológicas y Desarrollo Nuclear (CEADEN), Havana, Cuba
10
Centro de Investigación y de Estudios Avanzados (CINVESTAV), Mexico City and Mérida, Mexico
11
Centro Fermi, Museo Storico della Fisica e Centro Studi e Ricerche “Enrico Fermi’, Rome, Italy
12
Chicago State University, Chicago, IL, USA
13
China Institute of Atomic Energy, Beijing, China
14
Chonbuk National University, Jeonju, Republic of Korea
15
Faculty of Mathematics, Physics and Informatics, Comenius University Bratislava, Bratislava, Slovakia
16
COMSATS Institute of Information Technology (CIIT), Islamabad, Pakistan
17
Creighton University, Omaha, NE, USA
18
Department of Physics, Aligarh Muslim University, Aligarh, India
19
Department of Physics, Ohio State University, Columbus, OH, USA
20
Department of Physics, Pusan National University, Pusan, Republic of Korea
21
Department of Physics, Sejong University, Seoul, Republic of Korea
22
Department of Physics, University of Oslo, Oslo, Norway
23
Department of Physics and Technology, University of Bergen, Bergen, Norway
24
Dipartimento di Fisica dell’Università ’La Sapienza’ and Sezione INFN, Rome, Italy
25
Dipartimento di Fisica dell’Università and Sezione INFN, Cagliari, Italy
26
Dipartimento di Fisica dell’Università and Sezione INFN, Trieste, Italy
27
Dipartimento di Fisica dell’Università and Sezione INFN, Turin, Italy
28
Dipartimento di Fisica e Astronomia dell’Università and Sezione INFN, Bologna, Italy
29
Dipartimento di Fisica e Astronomia dell’Università and Sezione INFN, Catania, Italy
30
Dipartimento di Fisica e Astronomia dell’Università and Sezione INFN, Padua, Italy
31
Dipartimento di Fisica ‘E.R. Caianiello’ dell’Università and Gruppo Collegato INFN, Salerno, Italy
32
Dipartimento DISAT del Politecnico and Sezione INFN, Turin, Italy
33
Dipartimento di Scienze e Innovazione Tecnologica dell’Università del Piemonte Orientale and INFN Sezione di Torino, Alessandria, Italy
34
Dipartimento Interateneo di Fisica ‘M. Merlin’ and Sezione INFN, Bari, Italy
35
European Organization for Nuclear Research (CERN), Geneva, Switzerland
36
Faculty of Engineering and Business Administration, Western Norway University of Applied Sciences, Bergen, Norway
37
Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University in Prague, Prague, Czech Republic
38
Faculty of Science, P.J. Šafárik University, Kosice, Slovakia
39
Frankfurt Institute for Advanced Studies, Johann Wolfgang Goethe-Universität Frankfurt, Frankfurt, Germany
40
Gangneung-Wonju National University, Gangneung, Republic of Korea
41
Department of Physics, Gauhati University, Guwahati, India
42
Helmholtz-Institut für Strahlen- und Kernphysik, Rheinische Friedrich-Wilhelms-Universität Bonn, Bonn, Germany
43
Helsinki Institute of Physics (HIP), Helsinki, Finland
44
Hiroshima University, Hiroshima, Japan
45
Hochschule Worms, Zentrum für Technologietransfer und Telekommunikation (ZTT), Worms, Germany
46
Horia Hulubei National Institute of Physics and Nuclear Engineering, Bucharest, Romania
47
Indian Institute of Technology Bombay (IIT), Mumbai, India
48
Indian Institute of Technology Indore, Indore, India
49
Indonesian Institute of Sciences, Jakarta, Indonesia
50
INFN, Laboratori Nazionali di Frascati, Frascati, Italy
51
INFN, Sezione di Bari, Bari, Italy
52
INFN, Sezione di Bologna, Bologna, Italy
53
INFN, Sezione di Cagliari, Cagliari, Italy
54
INFN, Sezione di Catania, Catania, Italy
55
INFN, Sezione di Padova, Padua, Italy
56
INFN, Sezione di Roma, Rome, Italy
57
INFN, Sezione di Torino, Turin, Italy
58
INFN, Sezione di Trieste, Trieste, Italy
59
Inha University, Incheon, Republic of Korea
60
Institut de Physique Nucléaire d’Orsay (IPNO), Institut National de Physique Nucléaire et de Physique des Particules (IN2P3/CNRS), Université de Paris-Sud, Université Paris-Saclay, Orsay, France
61
Institute for Nuclear Research, Academy of Sciences, Moscow, Russia
62
Institute for Subatomic Physics of Utrecht University, Utrecht, Netherlands
63
Institute for Theoretical and Experimental Physics, Moscow, Russia
64
Institute of Experimental Physics, Slovak Academy of Sciences, Kosice, Slovakia
65
Institute of Physics, Bhubaneswar, India
66
Institute of Physics of the Czech Academy of Sciences, Prague, Czech Republic
67
Institute of Space Science (ISS), Bucharest, Romania
68
Institut für Kernphysik, Johann Wolfgang Goethe-Universität Frankfurt, Frankfurt, Germany
69
Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, Mexico City, Mexico
70
Instituto de Física, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
71
Instituto de Física, Universidad Nacional Autónoma de México, Mexico City, Mexico
72
iThemba LABS, National Research Foundation, Somerset West, South Africa
73
Johann-Wolfgang-Goethe Universität Frankfurt Institut für Informatik, Fachbereich Informatik und Mathematik, Frankfurt, Germany
74
Joint Institute for Nuclear Research (JINR), Dubna, Russia
75
Konkuk University, Seoul, Republic of Korea
76
Korea Institute of Science and Technology Information, Daejeon, Republic of Korea
77
KTO Karatay University, Konya, Turkey
78
Laboratoire de Physique Subatomique et de Cosmologie, Université Grenoble-Alpes, CNRS-IN2P3, Grenoble, France
79
Lawrence Berkeley National Laboratory, Berkeley, CA, USA
80
Department of Physics, Division of Particle Physics, Lund University, Lund, Sweden
81
Nagasaki Institute of Applied Science, Nagasaki, Japan
82
Nara Women’s University (NWU), Nara, Japan
83
Department of Physics, School of Science, National and Kapodistrian University of Athens, Athens, Greece
84
National Centre for Nuclear Research, Warsaw, Poland
85
National Institute of Science Education and Research, HBNI, Jatni, India
86
National Nuclear Research Center, Baku, Azerbaijan
87
National Research Centre Kurchatov Institute, Moscow, Russia
88
Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
89
Nikhef, National institute for subatomic physics, Amsterdam, The Netherlands
90
NRC Kurchatov Institute IHEP, Protvino, Russia
91
Nuclear Physics Group, NRNU Moscow Engineering Physics Institute, Moscow, Russia
92
STFC Daresbury Laboratory, Daresbury, UK
93
Nuclear Physics Institute of the Czech Academy of Sciences, Řež u Prahy, Czech Republic
94
Oak Ridge National Laboratory, Oak Ridge, TN, USA
95
Petersburg Nuclear Physics Institute, Gatchina, Russia
96
Physics Department, Faculty of science, University of Zagreb, Zagreb, Croatia
97
Physics Department, Panjab University, Chandigarh, India
98
Physics Department, University of Jammu, Jammu, India
99
Physics Department, University of Rajasthan, Jaipur, India
100
Physikalisches Institut, Eberhard-Karls-Universität Tübingen, Tübingen, Germany
101
Physikalisches Institut, Ruprecht-Karls-Universität Heidelberg, Heidelberg, Germany
102
Physik Department, Technische Universität München, Munich, Germany
103
Research Division and ExtreMe Matter Institute EMMI, GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt, Germany
104
Rudjer Bošković Institute, Zagreb, Croatia
105
Russian Federal Nuclear Center (VNIIEF), Sarov, Russia
106
Saha Institute of Nuclear Physics, Kolkata, India
107
School of Physics and Astronomy, University of Birmingham, Birmingham, UK
108
Sección Física, Departamento de Ciencias, Pontificia Universidad Católica del Perú, Lima, Peru
109
Stefan Meyer Institut für Subatomare Physik (SMI), Vienna, Austria
110
SUBATECH, IMT Atlantique, Université de Nantes, CNRS-IN2P3, Nantes, France
111
Suranaree University of Technology, Nakhon Ratchasima, Thailand
112
Technical University of Košice, Kosice, Slovakia
113
Technische Universität München, Excellence Cluster ’Universe’, Munich, Germany
114
The Henryk Niewodniczanski Institute of Nuclear Physics, Polish Academy of Sciences, Cracow, Poland
115
The University of Texas at Austin, Austin, TX, USA
116
Universidad Autónoma de Sinaloa, Culiacán, Mexico
117
Universidade de São Paulo (USP), São Paulo, Brazil
118
Universidade Estadual de Campinas (UNICAMP), Campinas, Brazil
119
Universidade Federal do ABC, Santo Andre, Brazil
120
University College of Southeast Norway, Tonsberg, Norway
121
University of Cape Town, Cape Town, South Africa
122
University of Houston, Houston, TX, USA
123
University of Jyväskylä, Jyväskylä, Finland
124
University of Liverpool, Liverpool, UK
125
Faculty of Electrical Engineering, Mechanical Engineering and Naval Architecture, University of Split, Split, Croatia
126
University of Tennessee, Knoxville, TX, USA
127
University of the Witwatersrand, Johannesburg, South Africa
128
University of Tokyo, Tokyo, Japan
129
University of Tsukuba, Tsukuba, Japan
130
Université Clermont Auvergne, CNRS/IN2P3, LPC, Clermont-Ferrand, France
131
Université de Lyon, Université Lyon 1, CNRS/IN2P3, IPN-Lyon, Villeurbanne, Lyon, France
132
Université de Strasbourg, CNRS, IPHC UMR 7178, 67000, Strasbourg, France
133
IRFU, Department de Physique Nucléaire (DPhN), Université Paris-Saclay Centre dÉtudes de Saclay (CEA), Saclay, France
134
Università degli Studi di Pavia, Pavia, Italy
135
Università di Brescia, Brescia, Italy
136
V. Fock Institute for Physics, St. Petersburg State University, St. Petersburg, Russia
137
Variable Energy Cyclotron Centre, Kolkata, India
138
Warsaw University of Technology, Warsaw, Poland
139
Wayne State University, Detroit, MI, USA
140
Institut für Kernphysik, Westfälische Wilhelms-Universität Münster, Münster, Germany
141
Wigner Research Centre for Physics, Hungarian Academy of Sciences, Budapest, Hungary
142
Yale University, New Haven, CT, USA
143
Yonsei University, Seoul, Republic of Korea
144
CERN, 1211, Geneva 23, Switzerland
* e-mail: alice-publications@cern.ch
Received:
25
January
2018
Accepted:
21
June
2018
Published online:
6
August
2018
Neutral pion and meson invariant differential yields were measured in non-single diffractive p–Pb collisions at
= 5.02 TeV with the ALICE experiment at the CERN LHC. The analysis combines results from three complementary photon measurements, utilizing the PHOS and EMCal calorimeters and the Photon Conversion Method. The invariant differential yields of
and
meson inclusive production are measured near mid-rapidity in a broad transverse momentum range of
and
, respectively. The measured
ratio increases with
and saturates for
> 4
at
. A deviation from
scaling is observed for
2
. The measured
ratio is consistent with previous measurements from proton-nucleus and pp collisions over the full
range. The measured
ratio at high
also agrees within uncertainties with measurements from nucleus–nucleus collisions. The
and
yields in p–Pb relative to the scaled pp interpolated reference,
, are presented for
20
and
20
, respectively. The results are compared with theoretical model calculations. The values of
are consistent with unity for transverse momenta above 2
. These results support the interpretation that the suppressed yield of neutral mesons measured in Pb–Pb collisions at LHC energies is due to parton energy loss in the hot QCD medium.
© CERN for the benefit of the ALICE collaboration, 2018