Physics Letters B (Sep 2018)
Search for C violation in the decay η → π0e+e− with WASA-at-COSY
- P. Adlarson,
- W. Augustyniak,
- W. Bardan,
- M. Bashkanov,
- F.S. Bergmann,
- M. Berłowski,
- A. Bondar,
- M. Büscher,
- H. Calén,
- I. Ciepał,
- H. Clement,
- E. Czerwiński,
- K. Demmich,
- R. Engels,
- A. Erven,
- W. Erven,
- W. Eyrich,
- P. Fedorets,
- K. Föhl,
- K. Fransson,
- F. Goldenbaum,
- A. Goswami,
- K. Grigoryev,
- C.-O. Gullström,
- L. Heijkenskjöld,
- V. Hejny,
- N. Hüsken,
- L. Jarczyk,
- T. Johansson,
- B. Kamys,
- G. Kemmerling,
- G. Khatri,
- A. Khoukaz,
- A. Khreptak,
- D.A. Kirillov,
- S. Kistryn,
- H. Kleines,
- B. Kłos,
- W. Krzemień,
- P. Kulessa,
- A. Kupść,
- A. Kuzmin,
- K. Lalwani,
- D. Lersch,
- B. Lorentz,
- A. Magiera,
- R. Maier,
- P. Marciniewski,
- B. Mariański,
- H.-P. Morsch,
- P. Moskal,
- H. Ohm,
- W. Parol,
- E. Perez del Rio,
- N.M. Piskunov,
- D. Prasuhn,
- D. Pszczel,
- K. Pysz,
- A. Pyszniak,
- J. Ritman,
- A. Roy,
- Z. Rudy,
- O. Rundel,
- S. Sawant,
- S. Schadmand,
- I. Schätti-Ozerianska,
- T. Sefzick,
- V. Serdyuk,
- B. Shwartz,
- K. Sitterberg,
- T. Skorodko,
- M. Skurzok,
- J. Smyrski,
- V. Sopov,
- R. Stassen,
- J. Stepaniak,
- E. Stephan,
- G. Sterzenbach,
- H. Stockhorst,
- H. Ströher,
- A. Szczurek,
- A. Trzciński,
- M. Wolke,
- A. Wrońska,
- P. Wüstner,
- A. Yamamoto,
- J. Zabierowski,
- M.J. Zieliński,
- J. Złomańczuk,
- P. Żuprański,
- M. Żurek,
- A. Wirzba
Affiliations
- P. Adlarson
- Division of Nuclear Physics, Department of Physics and Astronomy, Uppsala University, Box 516, 75120 Uppsala, Sweden
- W. Augustyniak
- Department of Nuclear Physics, National Centre for Nuclear Research, ul. Hoza 69, 00-681, Warsaw, Poland
- W. Bardan
- Institute of Physics, Jagiellonian University, Prof. Stanisława Łojasiewicza 11, 30-348 Kraków, Poland
- M. Bashkanov
- School of Physics and Astronomy, University of Edinburgh, James Clerk Maxwell Building, Peter Guthrie Tait Road, Edinburgh EH9 3FD, United Kingdom of Great Britain and Northern Ireland
- F.S. Bergmann
- Institut für Kernphysik, Westfälische Wilhelms-Universität Münster, Wilhelm-Klemm-Str. 9, 48149 Münster, Germany; Corresponding author.
- M. Berłowski
- High Energy Physics Department, National Centre for Nuclear Research, ul. Hoza 69, 00-681, Warsaw, Poland
- A. Bondar
- Budker Institute of Nuclear Physics of SB RAS, 11 Akademika Lavrentieva prospect, Novosibirsk, 630090, Russia; Novosibirsk State University, 2 Pirogova Str., Novosibirsk, 630090, Russia
- M. Büscher
- Peter Grünberg Institut, PGI-6 Elektronische Eigenschaften, Forschungszentrum Jülich, 52425 Jülich, Germany; Institut für Laser- und Plasmaphysik, Heinrich-Heine Universität Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
- H. Calén
- Division of Nuclear Physics, Department of Physics and Astronomy, Uppsala University, Box 516, 75120 Uppsala, Sweden
- I. Ciepał
- The Henryk Niewodniczański Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342 Kraków, Poland
- H. Clement
- Physikalisches Institut, Eberhard-Karls-Universität Tübingen, Auf der Morgenstelle 14, 72076 Tübingen, Germany; Kepler Center für Astro- und Teilchenphysik, Physikalisches Institut der Universität Tübingen, Auf der Morgenstelle 14, 72076 Tübingen, Germany
- E. Czerwiński
- Institute of Physics, Jagiellonian University, Prof. Stanisława Łojasiewicza 11, 30-348 Kraków, Poland
- K. Demmich
- Institut für Kernphysik, Westfälische Wilhelms-Universität Münster, Wilhelm-Klemm-Str. 9, 48149 Münster, Germany
- R. Engels
- Institut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, Germany
- A. Erven
- Zentralinstitut für Engineering, Elektronik und Analytik, Forschungszentrum Jülich, 52425 Jülich, Germany
- W. Erven
- Zentralinstitut für Engineering, Elektronik und Analytik, Forschungszentrum Jülich, 52425 Jülich, Germany
- W. Eyrich
- Physikalisches Institut, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erwin-Rommel-Str. 1, 91058 Erlangen, Germany
- P. Fedorets
- Institut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, Germany; Institute for Theoretical and Experimental Physics named by A.I. Alikhanov of National Research Centre “Kurchatov Institute”, 25 Bolshaya Cheremushkinskaya, Moscow, 117218, Russia
- K. Föhl
- II. Physikalisches Institut, Justus-Liebig-Universität Gießen, Heinrich-Buff-Ring 16, 35392 Giessen, Germany
- K. Fransson
- Division of Nuclear Physics, Department of Physics and Astronomy, Uppsala University, Box 516, 75120 Uppsala, Sweden
- F. Goldenbaum
- Institut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, Germany
- A. Goswami
- Institut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, Germany; Department of Physics, Indian Institute of Technology Indore, Khandwa Road, Simrol, Indore – 453552, Madhya Pradesh, India
- K. Grigoryev
- Institut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, Germany; High Energy Physics Division, Petersburg Nuclear Physics Institute named by B.P. Konstantinov of National Research Centre “Kurchatov Institute”, 1 mkr. Orlova roshcha, Leningradskaya Oblast, Gatchina, 188300, Russia
- C.-O. Gullström
- Division of Nuclear Physics, Department of Physics and Astronomy, Uppsala University, Box 516, 75120 Uppsala, Sweden
- L. Heijkenskjöld
- Division of Nuclear Physics, Department of Physics and Astronomy, Uppsala University, Box 516, 75120 Uppsala, Sweden
- V. Hejny
- Institut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, Germany
- N. Hüsken
- Institut für Kernphysik, Westfälische Wilhelms-Universität Münster, Wilhelm-Klemm-Str. 9, 48149 Münster, Germany
- L. Jarczyk
- Institute of Physics, Jagiellonian University, Prof. Stanisława Łojasiewicza 11, 30-348 Kraków, Poland
- T. Johansson
- Division of Nuclear Physics, Department of Physics and Astronomy, Uppsala University, Box 516, 75120 Uppsala, Sweden
- B. Kamys
- Institute of Physics, Jagiellonian University, Prof. Stanisława Łojasiewicza 11, 30-348 Kraków, Poland
- G. Kemmerling
- Zentralinstitut für Engineering, Elektronik und Analytik, Forschungszentrum Jülich, 52425 Jülich, Germany
- G. Khatri
- Institute of Physics, Jagiellonian University, Prof. Stanisława Łojasiewicza 11, 30-348 Kraków, Poland
- A. Khoukaz
- Institut für Kernphysik, Westfälische Wilhelms-Universität Münster, Wilhelm-Klemm-Str. 9, 48149 Münster, Germany
- A. Khreptak
- Institute of Physics, Jagiellonian University, Prof. Stanisława Łojasiewicza 11, 30-348 Kraków, Poland
- D.A. Kirillov
- Veksler and Baldin Laboratory of High Energy Physics, Joint Institute for Nuclear Physics, 6 Joliot-Curie, Dubna, 141980, Russia
- S. Kistryn
- Institute of Physics, Jagiellonian University, Prof. Stanisława Łojasiewicza 11, 30-348 Kraków, Poland
- H. Kleines
- Zentralinstitut für Engineering, Elektronik und Analytik, Forschungszentrum Jülich, 52425 Jülich, Germany
- B. Kłos
- August Chełkowski Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007, Katowice, Poland
- W. Krzemień
- High Energy Physics Department, National Centre for Nuclear Research, ul. Hoza 69, 00-681, Warsaw, Poland
- P. Kulessa
- The Henryk Niewodniczański Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342 Kraków, Poland
- A. Kupść
- Division of Nuclear Physics, Department of Physics and Astronomy, Uppsala University, Box 516, 75120 Uppsala, Sweden; High Energy Physics Department, National Centre for Nuclear Research, ul. Hoza 69, 00-681, Warsaw, Poland
- A. Kuzmin
- Budker Institute of Nuclear Physics of SB RAS, 11 Akademika Lavrentieva prospect, Novosibirsk, 630090, Russia; Novosibirsk State University, 2 Pirogova Str., Novosibirsk, 630090, Russia
- K. Lalwani
- Department of Physics, Malaviya National Institute of Technology Jaipur, JLN Marg Jaipur – 302017, Rajasthan, India
- D. Lersch
- Institut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, Germany
- B. Lorentz
- Institut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, Germany
- A. Magiera
- Institute of Physics, Jagiellonian University, Prof. Stanisława Łojasiewicza 11, 30-348 Kraków, Poland
- R. Maier
- Institut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, Germany; JARA–FAME, Jülich Aachen Research Alliance, Forschungszentrum Jülich, 52425 Jülich, and RWTH Aachen, 52056 Aachen, Germany
- P. Marciniewski
- Division of Nuclear Physics, Department of Physics and Astronomy, Uppsala University, Box 516, 75120 Uppsala, Sweden
- B. Mariański
- Department of Nuclear Physics, National Centre for Nuclear Research, ul. Hoza 69, 00-681, Warsaw, Poland
- H.-P. Morsch
- Department of Nuclear Physics, National Centre for Nuclear Research, ul. Hoza 69, 00-681, Warsaw, Poland
- P. Moskal
- Institute of Physics, Jagiellonian University, Prof. Stanisława Łojasiewicza 11, 30-348 Kraków, Poland
- H. Ohm
- Institut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, Germany
- W. Parol
- The Henryk Niewodniczański Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342 Kraków, Poland
- E. Perez del Rio
- Physikalisches Institut, Eberhard-Karls-Universität Tübingen, Auf der Morgenstelle 14, 72076 Tübingen, Germany; Kepler Center für Astro- und Teilchenphysik, Physikalisches Institut der Universität Tübingen, Auf der Morgenstelle 14, 72076 Tübingen, Germany
- N.M. Piskunov
- Veksler and Baldin Laboratory of High Energy Physics, Joint Institute for Nuclear Physics, 6 Joliot-Curie, Dubna, 141980, Russia
- D. Prasuhn
- Institut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, Germany
- D. Pszczel
- Division of Nuclear Physics, Department of Physics and Astronomy, Uppsala University, Box 516, 75120 Uppsala, Sweden; High Energy Physics Department, National Centre for Nuclear Research, ul. Hoza 69, 00-681, Warsaw, Poland
- K. Pysz
- The Henryk Niewodniczański Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342 Kraków, Poland
- A. Pyszniak
- Division of Nuclear Physics, Department of Physics and Astronomy, Uppsala University, Box 516, 75120 Uppsala, Sweden; Institute of Physics, Jagiellonian University, Prof. Stanisława Łojasiewicza 11, 30-348 Kraków, Poland
- J. Ritman
- Institut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, Germany; JARA–FAME, Jülich Aachen Research Alliance, Forschungszentrum Jülich, 52425 Jülich, and RWTH Aachen, 52056 Aachen, Germany; Institut für Experimentalphysik I, Ruhr-Universität Bochum, Universitätsstr. 150, 44780 Bochum, Germany
- A. Roy
- Department of Physics, Indian Institute of Technology Indore, Khandwa Road, Simrol, Indore – 453552, Madhya Pradesh, India
- Z. Rudy
- Institute of Physics, Jagiellonian University, Prof. Stanisława Łojasiewicza 11, 30-348 Kraków, Poland
- O. Rundel
- Institute of Physics, Jagiellonian University, Prof. Stanisława Łojasiewicza 11, 30-348 Kraków, Poland
- S. Sawant
- Department of Physics, Indian Institute of Technology Bombay, Powai, Mumbai – 400076, Maharashtra, India
- S. Schadmand
- Institut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, Germany
- I. Schätti-Ozerianska
- Institute of Physics, Jagiellonian University, Prof. Stanisława Łojasiewicza 11, 30-348 Kraków, Poland
- T. Sefzick
- Institut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, Germany
- V. Serdyuk
- Institut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, Germany
- B. Shwartz
- Budker Institute of Nuclear Physics of SB RAS, 11 Akademika Lavrentieva prospect, Novosibirsk, 630090, Russia; Novosibirsk State University, 2 Pirogova Str., Novosibirsk, 630090, Russia
- K. Sitterberg
- Institut für Kernphysik, Westfälische Wilhelms-Universität Münster, Wilhelm-Klemm-Str. 9, 48149 Münster, Germany
- T. Skorodko
- Physikalisches Institut, Eberhard-Karls-Universität Tübingen, Auf der Morgenstelle 14, 72076 Tübingen, Germany; Kepler Center für Astro- und Teilchenphysik, Physikalisches Institut der Universität Tübingen, Auf der Morgenstelle 14, 72076 Tübingen, Germany; Department of Physics, Tomsk State University, 36 Lenina Avenue, Tomsk, 634050, Russia
- M. Skurzok
- Institute of Physics, Jagiellonian University, Prof. Stanisława Łojasiewicza 11, 30-348 Kraków, Poland
- J. Smyrski
- Institute of Physics, Jagiellonian University, Prof. Stanisława Łojasiewicza 11, 30-348 Kraków, Poland
- V. Sopov
- Institute for Theoretical and Experimental Physics named by A.I. Alikhanov of National Research Centre “Kurchatov Institute”, 25 Bolshaya Cheremushkinskaya, Moscow, 117218, Russia
- R. Stassen
- Institut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, Germany
- J. Stepaniak
- High Energy Physics Department, National Centre for Nuclear Research, ul. Hoza 69, 00-681, Warsaw, Poland
- E. Stephan
- August Chełkowski Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007, Katowice, Poland
- G. Sterzenbach
- Institut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, Germany
- H. Stockhorst
- Institut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, Germany
- H. Ströher
- Institut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, Germany; JARA–FAME, Jülich Aachen Research Alliance, Forschungszentrum Jülich, 52425 Jülich, and RWTH Aachen, 52056 Aachen, Germany
- A. Szczurek
- The Henryk Niewodniczański Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342 Kraków, Poland
- A. Trzciński
- Department of Nuclear Physics, National Centre for Nuclear Research, ul. Hoza 69, 00-681, Warsaw, Poland
- M. Wolke
- Division of Nuclear Physics, Department of Physics and Astronomy, Uppsala University, Box 516, 75120 Uppsala, Sweden
- A. Wrońska
- Institute of Physics, Jagiellonian University, Prof. Stanisława Łojasiewicza 11, 30-348 Kraków, Poland
- P. Wüstner
- Zentralinstitut für Engineering, Elektronik und Analytik, Forschungszentrum Jülich, 52425 Jülich, Germany
- A. Yamamoto
- High Energy Accelerator Research Organisation KEK, Tsukuba, Ibaraki 305-0801, Japan
- J. Zabierowski
- Astrophysics Division, National Centre for Nuclear Research, Box 447, 90-950 Łódź, Poland
- M.J. Zieliński
- Institute of Physics, Jagiellonian University, Prof. Stanisława Łojasiewicza 11, 30-348 Kraków, Poland
- J. Złomańczuk
- Division of Nuclear Physics, Department of Physics and Astronomy, Uppsala University, Box 516, 75120 Uppsala, Sweden
- P. Żuprański
- Department of Nuclear Physics, National Centre for Nuclear Research, ul. Hoza 69, 00-681, Warsaw, Poland
- M. Żurek
- Institut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, Germany
- A. Wirzba
- Institut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, Germany; Institute for Advanced Simulation and Jülich Center for Hadron Physics, Forschungszentrum Jülich, 52425, Germany
- Journal volume & issue
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Vol. 784
pp. 378 – 384
Abstract
We report on the search for the rare decay η→π0e+e− which is of interest to study C violation in the electromagnetic interaction which would indicate contributions from physics beyond the Standard Model, since the allowed decay via a two-photon intermediate state is strongly suppressed. The experiment has been performed using the WASA-at-COSY installation, located at the COSY accelerator of the Forschungszentrum Jülich, Germany. In total 3×107 events of the reaction pd→3Heη have been recorded at an excess energy of Q=59.8MeV. Based on this data set the C parity violating decay η→π0γ⁎→π0e+e− via a single-photon intermediate state has been searched for, resulting in new upper limits of Γ(η→π0e+e−)/Γ(η→π+π−π0)<3.28×10−5 and Γ(η→π0e+e−)/Γ(η→all)<7.5×10−6 (CL=90%), respectively.
