https://doi.org/10.1140/epja/i2018-12585-3
Regular Article - Experimental Physics
Backward single-pion production in the 
reaction with WASA-at-COSY
1
Division of Nuclear Physics, Department of Physics and Astronomy, Uppsala University, Box 516, 75120, Uppsala, Sweden
2
Department of Nuclear Physics, National Centre for Nuclear Research, ul. Hoza 69, 00-681, Warsaw, Poland
3
Institute of Physics, Jagiellonian University, prof. Stanisława Łojasiewicza 11, 30-348, Kraków, Poland
4
School of Physics and Astronomy, University of Edinburgh, James Clerk Maxwell Building, Peter Guthrie Tait Road, EH9 3FD, Edinburgh, UK
5
Institut für Kernphysik, Westfälische Wilhelms-Universität Münster, Wilhelm-Klemm-Str. 9, 48149, Münster, Germany
6
High Energy Physics Department, National Centre for Nuclear Research, ul. Hoza 69, 00-681, Warsaw, Poland
7
Budker Institute of Nuclear Physics of SB RAS, 11 akademika Lavrentieva prospect, 630090, Novosibirsk, Russia
8
Novosibirsk State University, 2 Pirogova Str., 630090, Novosibirsk, Russia
9
Peter Grünberg Institut, PGI-6 Elektronische Eigenschaften, Forschungszentrum Jülich, 52425, Jülich, Germany
10
Institut für Laser- und Plasmaphysik, Heinrich-Heine Universität Düsseldorf, Universitätsstr. 1, 40225, Düsseldorf, Germany
11
The Henryk Niewodniczański Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342, Kraków, Poland
12
Physikalisches Institut, Eberhard-Karls-Universität Tübingen, Auf der Morgenstelle 14, 72076, Tübingen, Germany
13
Kepler Center für Astro- und Teilchenphysik, Physikalisches Institut der Universität Tübingen, Auf der Morgenstelle 14, 72076, Tübingen, Germany
14
Institut für Kernphysik, Forschungszentrum Jülich, 52425, Jülich, Germany
15
Zentralinstitut für Engineering, Elektronik und Analytik, Forschungszentrum Jülich, 52425, Jülich, Germany
16
Physikalisches Institut, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erwin-Rommel-Str. 1, 91058, Erlangen, Germany
17
Institute for Theoretical and Experimental Physics named after A.I. Alikhanov of National Research Centre “Kurchatov Institute”, 25 Bolshaya Cheremushkinskaya, 117218, Moscow, Russia
18
II. Physikalisches Institut, Justus-Liebig-Universität Gießen, Heinrich-Buff-Ring 16, 35392, Giessen, Germany
19
Department of Physics, Indian Institute of Technology Indore, Khandwa Road, Simrol, 453552, Indore, Madhya Pradesh, India
20
High Energy Physics Division, Petersburg Nuclear Physics Institute named after B.P. Konstantinov of National Research Centre “Kurchatov Institute”, 1 mkr. Orlova roshcha, 188300, Gatchina, Leningradskaya Oblast, Russia
21
Veksler and Baldin Laboratory of High Energy Physics, Joint Institute for Nuclear Physics, 6 Joliot-Curie, 141980, Dubna, Russia
22
August Chełkowski Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007, Katowice, Poland
23
Department of Physics, Malaviya National Institute of Technology Jaipur, JLN Marg Jaipur, 302017, Rajasthan, India
24
JARA-FAME, Jülich Aachen Research Alliance, Forschungszentrum Jülich and RWTH Aachen, Jülich, Aachen, Germany
25
Institut für Experimentalphysik I, Ruhr-Universität Bochum, Universitätsstr. 150, 44780, Bochum, Germany
26
Department of Physics, Tomsk State University, 36 Lenina Avenue, 634050, Tomsk, Russia
27
High Energy Accelerator Research Organisation KEK, 305-0801, Tsukuba, Ibaraki, Japan
28
Astrophysics Division, National Centre for Nuclear Research, Box 447, 90-950, Łódź, Poland
29
Physics and Astronomy Department, UCL, Gower Street, WC1E 6BT, London, UK
* e-mail: n.hues02@uni-muenster.de
Received:
21
May
2018
Accepted:
13
August
2018
Published online:
17
September
2018
New data on the production of single neutral pions in the reaction are presented. For fifteen proton beam momenta between 
GeV/c and 
GeV/c, differential cross sections are determined over a large fraction of the backward hemisphere. Since the only previous systematic measurements of single-pion production at these energies were made in collinear kinematics, the present work constitutes a significant extension of the current knowledge on this reaction. Even this far above the production threshold, significant changes are found in the behaviour of the angular distributions over small intervals in beam momentum.
© SIF, Springer-Verlag GmbH Germany, part of Springer Nature, 2018
