Search for C violation in the decay η → π0e+e− with WASA-at-COSY
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 experime...
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| Format: | Article |
| Language: | English |
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Elsevier
2018-09-01
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| Series: | Physics Letters B |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S0370269318305550 |
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Article |
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DOAJ |
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English |
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DOAJ |
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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 |
| spellingShingle |
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 Search for C violation in the decay η → π0e+e− with WASA-at-COSY Physics Letters B |
| author_facet |
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 |
| author_sort |
P. Adlarson |
| title |
Search for C violation in the decay η → π0e+e− with WASA-at-COSY |
| title_short |
Search for C violation in the decay η → π0e+e− with WASA-at-COSY |
| title_full |
Search for C violation in the decay η → π0e+e− with WASA-at-COSY |
| title_fullStr |
Search for C violation in the decay η → π0e+e− with WASA-at-COSY |
| title_full_unstemmed |
Search for C violation in the decay η → π0e+e− with WASA-at-COSY |
| title_sort |
search for c violation in the decay η → π0e+e− with wasa-at-cosy |
| publisher |
Elsevier |
| series |
Physics Letters B |
| issn |
0370-2693 |
| publishDate |
2018-09-01 |
| description |
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. |
| url |
http://www.sciencedirect.com/science/article/pii/S0370269318305550 |
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doaj-64a7159d2cec47a4b81c286162cb640a2020-11-25T00:43:11ZengElsevierPhysics Letters B0370-26932018-09-01784378384Search for C violation in the decay η → π0e+e− with WASA-at-COSYP. Adlarson0W. Augustyniak1W. Bardan2M. Bashkanov3F.S. Bergmann4M. Berłowski5A. Bondar6M. Büscher7H. Calén8I. Ciepał9H. Clement10E. Czerwiński11K. Demmich12R. Engels13A. Erven14W. Erven15W. Eyrich16P. Fedorets17K. Föhl18K. Fransson19F. Goldenbaum20A. Goswami21K. Grigoryev22C.-O. Gullström23L. Heijkenskjöld24V. Hejny25N. Hüsken26L. Jarczyk27T. Johansson28B. Kamys29G. Kemmerling30G. Khatri31A. Khoukaz32A. Khreptak33D.A. Kirillov34S. Kistryn35H. Kleines36B. Kłos37W. Krzemień38P. Kulessa39A. Kupść40A. Kuzmin41K. Lalwani42D. Lersch43B. Lorentz44A. Magiera45R. Maier46P. Marciniewski47B. Mariański48H.-P. Morsch49P. Moskal50H. Ohm51W. Parol52E. Perez del Rio53N.M. Piskunov54D. Prasuhn55D. Pszczel56K. Pysz57A. Pyszniak58J. Ritman59A. Roy60Z. Rudy61O. Rundel62S. Sawant63S. Schadmand64I. Schätti-Ozerianska65T. Sefzick66V. Serdyuk67B. Shwartz68K. Sitterberg69T. Skorodko70M. Skurzok71J. Smyrski72V. Sopov73R. Stassen74J. Stepaniak75E. Stephan76G. Sterzenbach77H. Stockhorst78H. Ströher79A. Szczurek80A. Trzciński81M. Wolke82A. Wrońska83P. Wüstner84A. Yamamoto85J. Zabierowski86M.J. Zieliński87J. Złomańczuk88P. Żuprański89M. Żurek90A. Wirzba91Division of Nuclear Physics, Department of Physics and Astronomy, Uppsala University, Box 516, 75120 Uppsala, SwedenDepartment of Nuclear Physics, National Centre for Nuclear Research, ul. Hoza 69, 00-681, Warsaw, PolandInstitute of Physics, Jagiellonian University, Prof. Stanisława Łojasiewicza 11, 30-348 Kraków, PolandSchool 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 IrelandInstitut für Kernphysik, Westfälische Wilhelms-Universität Münster, Wilhelm-Klemm-Str. 9, 48149 Münster, Germany; Corresponding author.High Energy Physics Department, National Centre for Nuclear Research, ul. Hoza 69, 00-681, Warsaw, PolandBudker Institute of Nuclear Physics of SB RAS, 11 Akademika Lavrentieva prospect, Novosibirsk, 630090, Russia; Novosibirsk State University, 2 Pirogova Str., Novosibirsk, 630090, RussiaPeter Grünberg Institut, PGI-6 Elektronische Eigenschaften, Forschungszentrum Jülich, 52425 Jülich, Germany; Institut für Laser- und Plasmaphysik, Heinrich-Heine Universität Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, GermanyDivision of Nuclear Physics, Department of Physics and Astronomy, Uppsala University, Box 516, 75120 Uppsala, SwedenThe Henryk Niewodniczański Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342 Kraków, PolandPhysikalisches 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, GermanyInstitute of Physics, Jagiellonian University, Prof. Stanisława Łojasiewicza 11, 30-348 Kraków, PolandInstitut für Kernphysik, Westfälische Wilhelms-Universität Münster, Wilhelm-Klemm-Str. 9, 48149 Münster, GermanyInstitut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, GermanyZentralinstitut für Engineering, Elektronik und Analytik, Forschungszentrum Jülich, 52425 Jülich, GermanyZentralinstitut für Engineering, Elektronik und Analytik, Forschungszentrum Jülich, 52425 Jülich, GermanyPhysikalisches Institut, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erwin-Rommel-Str. 1, 91058 Erlangen, GermanyInstitut 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, RussiaII. Physikalisches Institut, Justus-Liebig-Universität Gießen, Heinrich-Buff-Ring 16, 35392 Giessen, GermanyDivision of Nuclear Physics, Department of Physics and Astronomy, Uppsala University, Box 516, 75120 Uppsala, SwedenInstitut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, GermanyInstitut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, Germany; Department of Physics, Indian Institute of Technology Indore, Khandwa Road, Simrol, Indore – 453552, Madhya Pradesh, IndiaInstitut 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, RussiaDivision of Nuclear Physics, Department of Physics and Astronomy, Uppsala University, Box 516, 75120 Uppsala, SwedenDivision of Nuclear Physics, Department of Physics and Astronomy, Uppsala University, Box 516, 75120 Uppsala, SwedenInstitut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, GermanyInstitut für Kernphysik, Westfälische Wilhelms-Universität Münster, Wilhelm-Klemm-Str. 9, 48149 Münster, GermanyInstitute of Physics, Jagiellonian University, Prof. Stanisława Łojasiewicza 11, 30-348 Kraków, PolandDivision of Nuclear Physics, Department of Physics and Astronomy, Uppsala University, Box 516, 75120 Uppsala, SwedenInstitute of Physics, Jagiellonian University, Prof. Stanisława Łojasiewicza 11, 30-348 Kraków, PolandZentralinstitut für Engineering, Elektronik und Analytik, Forschungszentrum Jülich, 52425 Jülich, GermanyInstitute of Physics, Jagiellonian University, Prof. Stanisława Łojasiewicza 11, 30-348 Kraków, PolandInstitut für Kernphysik, Westfälische Wilhelms-Universität Münster, Wilhelm-Klemm-Str. 9, 48149 Münster, GermanyInstitute of Physics, Jagiellonian University, Prof. Stanisława Łojasiewicza 11, 30-348 Kraków, PolandVeksler and Baldin Laboratory of High Energy Physics, Joint Institute for Nuclear Physics, 6 Joliot-Curie, Dubna, 141980, RussiaInstitute of Physics, Jagiellonian University, Prof. Stanisława Łojasiewicza 11, 30-348 Kraków, PolandZentralinstitut für Engineering, Elektronik und Analytik, Forschungszentrum Jülich, 52425 Jülich, GermanyAugust Chełkowski Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007, Katowice, PolandHigh Energy Physics Department, National Centre for Nuclear Research, ul. Hoza 69, 00-681, Warsaw, PolandThe Henryk Niewodniczański Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342 Kraków, PolandDivision 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, PolandBudker Institute of Nuclear Physics of SB RAS, 11 Akademika Lavrentieva prospect, Novosibirsk, 630090, Russia; Novosibirsk State University, 2 Pirogova Str., Novosibirsk, 630090, RussiaDepartment of Physics, Malaviya National Institute of Technology Jaipur, JLN Marg Jaipur – 302017, Rajasthan, IndiaInstitut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, GermanyInstitut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, GermanyInstitute of Physics, Jagiellonian University, Prof. Stanisława Łojasiewicza 11, 30-348 Kraków, PolandInstitut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, Germany; JARA–FAME, Jülich Aachen Research Alliance, Forschungszentrum Jülich, 52425 Jülich, and RWTH Aachen, 52056 Aachen, GermanyDivision of Nuclear Physics, Department of Physics and Astronomy, Uppsala University, Box 516, 75120 Uppsala, SwedenDepartment of Nuclear Physics, National Centre for Nuclear Research, ul. Hoza 69, 00-681, Warsaw, PolandDepartment of Nuclear Physics, National Centre for Nuclear Research, ul. Hoza 69, 00-681, Warsaw, PolandInstitute of Physics, Jagiellonian University, Prof. Stanisława Łojasiewicza 11, 30-348 Kraków, PolandInstitut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, GermanyThe Henryk Niewodniczański Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342 Kraków, PolandPhysikalisches 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, GermanyVeksler and Baldin Laboratory of High Energy Physics, Joint Institute for Nuclear Physics, 6 Joliot-Curie, Dubna, 141980, RussiaInstitut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, GermanyDivision 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, PolandThe Henryk Niewodniczański Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342 Kraków, PolandDivision 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, PolandInstitut 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, GermanyDepartment of Physics, Indian Institute of Technology Indore, Khandwa Road, Simrol, Indore – 453552, Madhya Pradesh, IndiaInstitute of Physics, Jagiellonian University, Prof. Stanisława Łojasiewicza 11, 30-348 Kraków, PolandInstitute of Physics, Jagiellonian University, Prof. Stanisława Łojasiewicza 11, 30-348 Kraków, PolandDepartment of Physics, Indian Institute of Technology Bombay, Powai, Mumbai – 400076, Maharashtra, IndiaInstitut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, GermanyInstitute of Physics, Jagiellonian University, Prof. Stanisława Łojasiewicza 11, 30-348 Kraków, PolandInstitut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, GermanyInstitut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, GermanyBudker Institute of Nuclear Physics of SB RAS, 11 Akademika Lavrentieva prospect, Novosibirsk, 630090, Russia; Novosibirsk State University, 2 Pirogova Str., Novosibirsk, 630090, RussiaInstitut für Kernphysik, Westfälische Wilhelms-Universität Münster, Wilhelm-Klemm-Str. 9, 48149 Münster, GermanyPhysikalisches 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, RussiaInstitute of Physics, Jagiellonian University, Prof. Stanisława Łojasiewicza 11, 30-348 Kraków, PolandInstitute of Physics, Jagiellonian University, Prof. Stanisława Łojasiewicza 11, 30-348 Kraków, PolandInstitute for Theoretical and Experimental Physics named by A.I. Alikhanov of National Research Centre “Kurchatov Institute”, 25 Bolshaya Cheremushkinskaya, Moscow, 117218, RussiaInstitut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, GermanyHigh Energy Physics Department, National Centre for Nuclear Research, ul. Hoza 69, 00-681, Warsaw, PolandAugust Chełkowski Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007, Katowice, PolandInstitut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, GermanyInstitut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, GermanyInstitut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, Germany; JARA–FAME, Jülich Aachen Research Alliance, Forschungszentrum Jülich, 52425 Jülich, and RWTH Aachen, 52056 Aachen, GermanyThe Henryk Niewodniczański Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342 Kraków, PolandDepartment of Nuclear Physics, National Centre for Nuclear Research, ul. Hoza 69, 00-681, Warsaw, PolandDivision of Nuclear Physics, Department of Physics and Astronomy, Uppsala University, Box 516, 75120 Uppsala, SwedenInstitute of Physics, Jagiellonian University, Prof. Stanisława Łojasiewicza 11, 30-348 Kraków, PolandZentralinstitut für Engineering, Elektronik und Analytik, Forschungszentrum Jülich, 52425 Jülich, GermanyHigh Energy Accelerator Research Organisation KEK, Tsukuba, Ibaraki 305-0801, JapanAstrophysics Division, National Centre for Nuclear Research, Box 447, 90-950 Łódź, PolandInstitute of Physics, Jagiellonian University, Prof. Stanisława Łojasiewicza 11, 30-348 Kraków, PolandDivision of Nuclear Physics, Department of Physics and Astronomy, Uppsala University, Box 516, 75120 Uppsala, SwedenDepartment of Nuclear Physics, National Centre for Nuclear Research, ul. Hoza 69, 00-681, Warsaw, PolandInstitut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, GermanyInstitut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, Germany; Institute for Advanced Simulation and Jülich Center for Hadron Physics, Forschungszentrum Jülich, 52425, GermanyWe 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.http://www.sciencedirect.com/science/article/pii/S0370269318305550 |