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1. Scalar isoscalar mesons and the scalar glueball from radiative $J/\psi$ decays

Author

U. Thoma, I. Denisenko, Eberhard Klempt, and A. V. Sarantsev

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Meson, Octet, 010308 nuclear & particles physics, Glueball, Isoscalar, Scalar (mathematics), High Energy Physics::Phenomenology, Nuclear Theory, 01 natural sciences, lcsh:QC1-999, High Energy Physics - Phenomenology, Amplitude, 0103 physical sciences, Radiative transfer, High Energy Physics::Experiment, Singlet state, 010306 general physics, Nuclear Experiment, lcsh:Physics
Abstract

A coupled-channel analysis of BESIII data on radiative $J/\psi$ decays into $\pi\pi$, $K\bar K$, $\eta\eta$ and $\omega\phi$ has been performed. The partial-wave amplitude is constrained by a large number of further data. The analysis finds ten isoscalar scalar mesons. Their masses, widths and decay modes are determined. The scalar mesons are interpreted as mainly SU(3)-singlet and mainly octet states. Octet isoscalar scalar states are observed with significant yields only in the 1500-2100\,MeV mass region. Singlet scalar mesons are produced over a wide mass range but their yield peaks in the same mass region. The peak is interpreted as scalar glueball. Its mass and width are determined to $M=1865$\er25$^{+10}_{-30}$ {\rm MeV} and $\Gamma= 370$\er$50^{+30}_{-20}$ {\rm MeV}, its yield in radiative $J/\psi$ decays to ($5.8\pm 1.0)\,10^{-3}$., Comment: 11 pages, 4 figures

Published
2021

2. The potential of $\varLambda $ and $\varXi ^-$ studies with PANDA at FAIR

Author

M. Sachs, I. K. Keshk, Xi-Guang Cao, M. Traxler, Yan Liang, G. Mazza, C. Fritzsch, T. Holtmann, S. Godre, A. N. Skachkova, Edward Lisowski, E. Rosenthal, S. Yogesh, Y. K. Sun, H. Pace, D. A. Morozov, H. Deppe, J. Pütz, A. G. Denig, S. Ryzhikov, Hans-Georg Zaunick, Dirk Grunwald, A. Kantsyrev, Paolo Mengucci, Christoph Herold, P. Eugenio, Grzegorz Filo, A. Boukharov, M. Kesselkaul, Concettina Sfienti, A. Kulkarni, M. Lattery, J. Frech, A. Hayrapetyan, W. Zhu, A. A. Piskun, Zbigniew Rudy, V. E. Blinov, S. Spataro, Jens Hartmann, S. Schlimme, D. Branford, C. Schwarz, Michaela Thiel, G. Golovanov, T. Wasem, J. Schwiening, P. Wieczorek, E. Pyata, Ch. Hammann, D. Lehmann, Chinorat Kobdaj, V. Moiseev, P. Balanutsa, B. J. Liu, S. Bodenschatz, F. E. Maas, N. Wongprachanukul, Lorenzo Scalise, M. Hoek, A. K. Saxena, M. Virius, M. Steinke, N. Rathod, A.A. Efremov, A. Samartsev, I. Shein, Alexander Olshevskiy, Herbert Koch, V. Panjushkin, K. Nowakowski, S. Belostotski, S. Bukreeva, Ulrich Wiedner, U. Thöring, A.S. Vodopianov, J. Kellers, L. Robison, Ting Xiao, V. Crede, Egle Tomasi-Gustafsson, R. Karabowicz, P. Srisawad, F. Feldbauer, J. Reher, D. Kazlou, M. Yu. Barabanov, W. Kühn, M. Steinen, P. Wintz, D. Wölbing, A. Dbeyssi, M. Kunze, C. Hargens, A. Pitka, A. Lehmann, I. Augustin, Mathias Fink, P. Terlecki, A. E. Yakutin, Magnus Wolke, I. Kisel, V. Varentsov, U. Thoma, Nicola Bianchi, D. Bettoni, Antoni Szczurek, Dan Pantea, M. Slunecka, D. I. Glazier, H. H. Leithoff, Genady Gavrilov, P. Jiang, T. Simantathammakul, Felice Iazzi, E. Widmann, D. G. Ireland, C. Motzko, K.-T. Brinkmann, M. Schmidt, Johann Marton, J. Tao, W. Eyrich, M. Straube, Krzysztof Swientek, B. Krusche, N. K. Walford, S. Vejdani, G. Perez Andrade, Richard Wheadon, N. Kratochwil, H. Li, L. Jokhovets, S.G. Pivovarov, W. Ikegami Andersson, S. Grieser, A. Gerhardt, H. Qi, W. Lauth, S. Diehl, R. Beck, Krzysztof Korcyl, Angelo Rivetti, K. Makonyi, Yupeng Yan, P. P. Natali, G. Kesik, K. N. Basant, I. Lehmann, A. V. Stavinskiy, W. Esmail, M. Preston, A. Gillitzer, D. Calvo, Ayut Limphirat, A. Demekhin, J. Müllers, M. Pelizäus, Andrew Levin, Gianangelo Bracco, N. Quin, D. Lersch, V. Chernetsky, M. Domagala, N. Minaev, A. Balashoff, U. Müller, N. Hüsken, V. Abramov, Torbjörn Bäck, A. Ali, S. Pflüger, C. Yu, G. Boca, R. Klasen, N. Kristi, J. Zmeskal, T. Nasawad, A. Dolgolenko, A. Belousov, B. Wohlfahrt, H. Xu, R. Dosdall, E. Maslova, Gianni Barucca, M.P. Bussa, B. Seitz, J. S. Díaz, G. Hunter, M. Volf, V.Kh. Dodokhov, Piotr Lebiedowicz, A. Scholl, Grzegorz Korcyl, H. Loehner, Mohammed Al-Turany, Andrzej Kupsc, R. W. Novotny, L. Montalto, A. E. Blinov, J. Kannika, Andrey Uzunian, R. Lalik, P. N. Deepak, P.-E. Tegnér, E. Antokhin, A. Gerasimov, P. De Remigis, X. Zhou, Petr Gallus, P. Orsich, I. Prochazka, Valentino Rigato, S. Maldaner, M. Himmelreich, V. M. Abazov, J. Płażek, Kazem Azizi, James Ritman, S. Wolff, Andrea Bianconi, Nicola Paone, W. Nalti, S. Kegel, I. A. Kuyanov, M. Steinacher, A. Chlopik, V. Lucherini, A. Belias, K. K. Seth, Mario Bragadireanu, C. J. Schmidt, V. Freudenreich, A. Ehret, G. V. Fedotov, J. Li, A. Galoyan, G. Neue, P. Schakel, M. Wojciechowski, B. Kopf, C. Liu, P. Gianotti, X. Ma, R. Kappert, Oleg V. Missevitch, J. Pereira-de-Lira, X. Zhang, D. Melnychuk, Paweł Moskal, I. Köseoglu, Bo Cederwall, K. Götzen, M. Finger, M. Marcisovsky, A. Derevschikov, V. Goryachev, V. Jary, R. Kunne, Y. Zhou, G. Reicherz, C. Schnier, J. G. Messchendorp, M. Michałek, T. Erlen, D. Miehling, G. D. Alexeev, Hasko Stenzel, A. Fechtchenko, L. Schmitt, J. Rieger, M. Zyzak, Michael Papenbrock, F. Schupp, Sean A Dobbs, J. Pochodzalla, S. Chernichenko, S. Shimanski, A. Mustafa, K. Dutta, M. Kümmel, S. Bökelmann, S. Sun, Bruce Yabsley, I. Zimmermann, E.K. Koshurnikov, B. Zwieglinski, O. Malyshev, H. Flemming, O. Korchak, U. Kurilla, F. Nerling, M. Pugach, Claude Amsler, G. Huang, A. Akram, L. Sohl, B. J. Roy, S. Wronka, Andrey V. Izotov, Vaclav Vrba, A. Malige, M. Kuhlmann, E. Prencipe, R. Böhm, R. Schubert, Matthias Richter, M. Krebs, L. Nogach, Frank Goldenbaum, B. Ramstein, X. Y. Shen, Paul Alois Buhler, S. I. Manaenkov, A. Aycock, M. Küßner, A. Khoukaz, E. Luschevskaya, K. Khosonthongkee, C. Wenzel, M. Pfaffinger, J. Lühning, P. Poznański, Fabrizio Daví, S. Koch, O. Corell, M. Kavatsyuk, Bernd Voss, B. Hetz, Daniele Rinaldi, J. Regina, L. Capozza, J. Novy, V. Ferapontov, A. Kozela, D. Y. Kirin, U. Lynen, T. Johansson, S. Orfanitski, M. Tomasek, A. Derichs, Andrea Lavagno, Krisztian Peters, A. Ryazantsev, Daniel Duda, Valery Dormenev, M. Peskova, X. A. Xiong, O. Noll, M. Rossbach, M. Fritsch, N. I. Zhuravlev, Tomasz Fiutowski, S. Zimmermann, Y. Melnik, V. A. Matveev, A. Täschner, P. Salabura, S.A. Kononov, T. Triffterer, J. S. Lange, K. Pysz, K. Kalita, W. Erni, Ajay Kumar Rai, D. P. Watts, Lennart Isaksson, Utpal N. Roy, M. Strickert, M. Böhm, M. Albrecht, Y. Bettner, Boris Batyunya, A. Hamdi, J. Hofmann, Jize Zhao, R. Dzhygadlo, T. Held, V. V. Tokmenin, K. Manasatitpong, Andrei Fedorov, H. Orth, Hans Calén, M. Urban, G. Zhao, F. Lisowski, Witold Przygoda, D. Prasuhn, M. Zambrana, W. Schäfer, S. Bleser, A. K. Hergemöller, M. Pesek, Y. A. Tikhonov, A. Filippi, M. Peter, Volker Metag, M. Moritz, A. Kripko, J. Tarasiuk, S. Schadmand, G. Schepers, S. Poslavskiy, Andreas Martin Heinz, Anne-Laure Martin, L. Brück, Antonin Kveton, V. Mochalov, D. Steinschaden, M. Bölting, N. Er, Ch. Schmidt, Mikhail Korzhik, V. Astakhov, Konstantin Beloborodov, H. Denizli, T. Saito, R. Hagdorn, Pawel Marciniewski, D. Veretennikov, C. Morales Morales, Harphool Kumawat, Karin Schönning, Marek Idzik, M. O. Distler, A. Golubev, E. Ladygina, G. Kozlov, Tobias Stockmanns, C. Hahn, N. Cao, T. Sefzick, Giovanni Lancioni, V. Serdyuk, B. Ketzer, Jerzy Smyrski, D. Bonaventura, P. Wüstner, Yu. Yu. Lobanov, V. Pothodi Chackara, Mariana Nanova, B. Salisbury, E. A. Kravchenko, L. Tomasek, D. Bumrungkoh, Patrick Achenbach, W. Alkakhi, V. Uzhinsky, Y. Goncharenko, Harald Merkel, A. Atac, D. Rodríguez Piñeiro, A. Verkheev, P. Fedorets, S. Nakhoul, F. H. Heinsius, Q. Hu, N. B. Skachkov, S. Pongampai, R. Schmitz, E. A. Strokovsky, Zhiyong Liu, H. Peng, V. Arefiev, K. Föhl, D. Liu, P. Semenov, V. Rodin, Keval Gandhi, P. Kulessa, O. Miklukho, A. Vasiliev, P. Brand, A. A. Zhdanov, R. Kliemt, P. Grasemann, A. Yu. Barnyakov, Z. Li, A. Meschanin, Michael Düren, S. Ahmed, Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), PANDA, Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), BAİBÜ, Fen Edebiyat Fakültesi, Fizik Bölümü, Denizli, Haluk, and 0-Belirlenecek

Subjects
+Antixi+Xi%22">anti-p p --> Antixi Xi, Hadron, hyperon: pair production, correction: efficiency, 01 natural sciences, 13.30.-a, symmetry: CP, High Energy Physics - Experiment, Subatomär fysik, benchmark, Subatomic Physics, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], Electromagnetic Form-Factors, Nuclear Experiment, Spin-½, Physics, Antihyperon Production, Hyperon, PANDA, strong interaction, Observable, hyperon: production, 13.88.+, +Antilambda+Lambda%22">anti-p p --> Antilambda Lambda, Production (computer science), Low-Energy, Nuclear and High Energy Physics, Particle physics, Cp-Violation, +Lambda+pi%22">Xi- --> Lambda pi, Bar (music), spin: correlation, Strong interaction, Hyperons, nonperturbative, 13.60.R, hyperon: decay, 0103 physical sciences, anti-p p: scattering, ddc:530, anti-p: beam, 010306 general physics, polarization, 010308 nuclear & particles physics, background, High Energy Physics::Phenomenology, antihyperon, [No Keywords], Exchange, 13.75.-n, Decay, hyperon: ground state, Antiproton, High Energy Physics::Experiment
Abstract

The antiproton experiment PANDA at FAIR is designed to bring hadron physics to a new level in terms of scope, precision and accuracy. In this work, its unique capability for studies of hyperons is outlined. We discuss ground-state hyperons as diagnostic tools to study non-perturbative aspects of the strong interaction, and fundamental symmetries. New simulation studies have been carried out for two benchmark hyperon-antihyperon production channels: $\bar{p}p \to \bar{\Lambda}\Lambda$ and $\bar{p}p \to \bar{\Xi}^+\Xi^-$. The results, presented in detail in this paper, show that hyperon-antihyperon pairs from these reactions can be exclusively reconstructed with high efficiency and very low background contamination. In addition, the polarisation and spin correlations have been studied, exploiting the weak, self-analysing decay of hyperons and antihyperons. Two independent approaches to the finite efficiency have been applied and evaluated: one standard multidimensional efficiency correction approach, and one efficiency independent approach. The applicability of the latter was thoroughly evaluated for all channels, beam momenta and observables. The standard method yields good results in all cases, and shows that spin observables can be studied with high precision and accuracy already in the first phase of data taking with PANDA., Comment: 26 pages, 16 figures. Changes: Revised title and abstract and corrections/clarifications in the text according to suggestions by journal referees

Published
2021

3. Study of excited $$arvec{arXi }$$ baryons with the $$overline{ ext{ P }}$$ANDA detector

Author

Egle Tomasi-Gustafsson, R. Karabowicz, A. Kripko, M. Domagala, U. Müller, Pawel Marciniewski, D. Veretennikov, Xuan Zhang, Y. A. Tikhonov, A. Hamdi, J. Hofmann, A. Filippi, A. Golubev, Tobias Stockmanns, V. Abramov, C. Hahn, A. Belias, K. Nowakowski, V. Serdyuk, M. Pelizä, Z. Tavukoglu, B. Ketzer, Jerzy Smyrski, J. Pütz, O. Malyshev, U. Kurilla, Konstantin Beloborodov, V. Chauhan, R. W. Novotny, A. Kantsyrev, P. Balanutsa, B. J. Liu, D. G. Ireland, Petr Gallus, G. D. Alexeev, D. Bonaventura, A. V. Stavinskiy, C. Motzko, K.-T. Brinkmann, H. Denizli, V. Crede, I. Zimmermann, E.K. Koshurnikov, Jize Zhao, R. Dzhygadlo, Kazem Azizi, A. Chlopik, Fabrizio Daví, V. Ferapontov, D. Y. Kirin, P. Wüstner, M. Fritsch, N. I. Zhuravlev, D. Rodríguez Piñeiro, Dan Pantea, A. Täschner, W. Eyrich, T. Held, W. Esmail, T. Triffterer, V. V. Tokmenin, K. Manasatitpong, W. Kühn, A. Khoukaz, A. Ali, Alexander Olshevskiy, S. Koch, J. Rieger, R. Hagdorn, S. Godre, V. Lucherini, T. Erlen, Herbert Koch, Y. K. Sun, Mariana Nanova, A. Verkheev, M. Marcisovsky, P. Fedorets, Yan Liang, Claude Amsler, M. Slunecka, S. Nakhoul, J. Müllers, Krisztian Peters, J. Oppotsch, A. Malige, N. Hüsken, B. Salisbury, G. Huang, S. Sun, F. Nerling, A. A. Piskun, F. H. Heinsius, G. Mazza, S. I. Manaenkov, O. Noll, A. T. Olgun, E. Antokhin, A. Gerasimov, S. Spataro, P. Salabura, D. Bumrungkoh, Q. Hu, Kamal K. Seth, D. P. Watts, S. Shimanski, V. Uzhinsky, M. Krebs, S. Bodenschatz, Karin Schönning, C. Yu, G. Perez-Andrade, G. Boca, Krzysztof Swientek, V. E. Blinov, P. De Remigis, C. J. Schmidt, Paolo Mengucci, Christoph Herold, F. Lisowski, E. A. Strokovsky, N. B. Skachkov, Y. Goncharenko, Harald Merkel, Lennart Isaksson, S. Maldaner, S. Pongampai, F. Khalid, W. Lauth, F. Feldbauer, G. Reicherz, Volker Metag, C. Mannweiler, M. Moritz, L. Montalto, Piotr Lebiedowicz, D. Prasuhn, A. Scholl, Michaela Thiel, R. Schmitz, S. Pflüger, J. Kannika, M. Albrecht, M. Volf, V.Kh. Dodokhov, P. Poznański, Marek Idzik, M. O. Distler, I. Shein, T. Wasem, J. Schwiening, T. Sefzick, Giovanni Lancioni, J. Tarasiuk, E. Ladygina, Hans-Georg Zaunick, A. E. Blinov, N. Wongprachanukul, W. Schäfer, S. Schadmand, G. Schepers, Yu. Yu. Lobanov, I. Augustin, Mathias Fink, D. Lehmann, P. Terlecki, P. Eugenio, Concettina Sfienti, S. Poslavskiy, M. Virius, S. Schlimme, C. Schwarz, Andreas Martin Heinz, Andrey Uzunian, B. Zwieglinski, M. Lattery, A. E. Yakutin, P.-E. Tegnér, H. Peng, J. Pereira-de-Lira, Ting Xiao, A.A. Efremov, James Ritman, L. Brück, Antonin Kveton, V. Mochalov, V. M. Abazov, S. Wolff, E. A. Kravchenko, E. Prencipe, F. E. Maas, R. Beck, Krzysztof Korcyl, Lorenzo Scalise, Gianangelo Bracco, L. Tomasek, Patrick Achenbach, A. Derevschikov, E. Vishnevsky, D. Melnychuk, M. Firlej, P. Srisawad, A. Dbeyssi, J. Petersen, I. Köseoglu, D. Miehling, M. Bölting, J. Regina, P. Wintz, J. Reher, W. Alkakhi, H. H. Leithoff, S. Bleser, S. Kegel, N. Er, S. Pankonin, Antoni Szczurek, D. Kazlou, M. Yu. Barabanov, Dirk Grunwald, L. Capozza, L. Linzen, D. Liu, V. Freudenreich, A. Ehret, C. Liu, Yupeng Yan, P. Gianotti, R. Dosdall, Ch. Schmidt, M. Steinen, Y. Zhou, A. Demekhin, A. Galoyan, M. Preston, Zhengtai Liu, T. Holtmann, Paweł Moskal, Mikhail Korzhik, A. Boukharov, D. Klostermann, S. Orfanitski, E. Pyata, P. P. Natali, G. Golovanov, M. Pesek, Ch. Hammann, C. Schnier, J. G. Messchendorp, P. Semenov, V. Rodin, Valentino Rigato, B. Kopf, Keval Gandhi, Daniel Duda, Andrea Bianconi, D. I. Glazier, A. Gillitzer, A. Akram, H. Flemming, M. Kümmel, M. Steinke, I. A. Kuyanov, N. Rathod, D. Calvo, D. Wölbing, R. Böhm, Ali Yilmaz, F. Schupp, Sean A Dobbs, J. Pochodzalla, U. Lynen, S. Chernichenko, B. Krusche, Felice Iazzi, Richard Wheadon, X. Y. Shen, L. Jokhovets, S.G. Pivovarov, R. Kappert, A. Lehmann, Ayut Limphirat, P. Kulessa, I. Lehmann, Andrea Lavagno, N. Kristi, T. Nasawad, A. Dolgolenko, M. Peskova, J. Płażek, Tomasz Fiutowski, L. Nogach, G. V. Fedotov, E. Luschevskaya, E. Maslova, R. Lalik, K. Khosonthongkee, C. Wenzel, M. Pfaffinger, Grzegorz Korcyl, O. Miklukho, A. N. Skachkova, Edward Lisowski, V. Jary, M. Kavatsyuk, M. Himmelreich, H. Deppe, A. G. Denig, A. Vasiliev, A. Derichs, J. Frech, A. Hayrapetyan, W. Zhu, Chinorat Kobdaj, P. Brand, E. Rosenthal, S. Belostotski, Ulrich Wiedner, A.S. Vodopianov, J. Kellers, U. Keskin, U. Thoma, R. Kliemt, A. Yu. Barnyakov, Bo Cederwall, K. Götzen, A. Meschanin, Michael Düren, Johann Marton, V. Chernetsky, Gianni Barucca, H. Loehner, Vaclav Vrba, M. Sachs, I. K. Keshk, Xi-Guang Cao, M. Traxler, S. Diehl, Andrew Levin, M.P. Bussa, S. Yerlikaya, Nicola Paone, A. Samartsev, P. Jiang, A. Fechtchenko, L. Schmitt, Michael Papenbrock, Bernd Voss, B. Hetz, Daniele Rinaldi, V. Moiseev, Magnus Wolke, V. Varentsov, M. Schmidt, N. Minaev, A. Balashoff, Mohammed Al-Turany, Andrzej Kupsc, P. Orsich, M. Steinacher, M. Finger, V. Panjushkin, H. Xu, M. Michałek, S. Bökelmann, S. Wronka, Andrey V. Izotov, M. Bukharova, G. Neue, R. Schubert, M. Tomasek, D. A. Morozov, S. Zimmermann, J. Grochowski, P. Wieczorek, S. Ryzhikov, M. Hoek, A. Gerhardt, H. Qi, Jens Hartmann, B. Seitz, S. Bukreeva, X. Zhou, G. Kesik, I. Prochazka, Mario Bragadireanu, K. Pysz, S. Coen, O. Korchak, K. Kalita, M. Küßner, O. Corell, T. Johansson, A. Ryazantsev, Y. Melnik, V. A. Matveev, S.A. Kononov, H. Orth, Hans Calén, M. Urban, G. Zhao, Witold Przygoda, T. Simantathammakul, J. Moron, J. Li, Oleg V. Missevitch, Frank Goldenbaum, Ajay Kumar Rai, M. Strickert, M. Böhm, Grzegorz Filo, M. Kunze, W. Ikegami Andersson, R. Klasen, S. Vestrick, Paul Alois Buhler, J. Lühning, J. Novy, Valery Dormenev, Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay

Subjects
Nuclear and High Energy Physics, hyperon: particle source, Hadron, Type (model theory), [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, decay modes, Combinatorics, Tree (descriptive set theory), excited state: spectrum, 0103 physical sciences, ddc:530, structure, 010306 general physics, Nuclear Experiment, Physics, 010308 nuclear & particles physics, baryon: excited state, Spectrum (functional analysis), Hyperon, anti-p, Baryon, statistics, efficiency, Excited state, Production (computer science), acceptance
Abstract

The European physical journal / A 57(4), 149 (2021). doi:10.1140/epja/s10050-021-00444-5, Published by Springer, Heidelberg

Published
2021

4. PANDA Phase One: PANDA collaboration

Author

R. Klasen, S. Vestrick, Grzegorz Filo, S. Diehl, M. Kunze, W. Ikegami Andersson, A. V. Stavinskiy, Yupeng Yan, Felice Iazzi, D. Rodríguez Piñeiro, J. Müllers, Andrew Levin, Paul Alois Buhler, J. Lühning, J. Novy, Valery Dormenev, James Ritman, Piotr Lebiedowicz, L. Montalto, M. Küßner, A. Scholl, Frank Goldenbaum, Ali Yilmaz, Yan Liang, W. Esmail, M.P. Bussa, A. Ali, L. Jokhovets, S.G. Pivovarov, D. Bonaventura, A. Verkheev, S. Rimjaem, M. Preston, A. T. Olgun, Konstantin Beloborodov, P. Fedorets, A. Hamdi, M. Volf, S. Yerlikaya, S. Nakhoul, J. Kannika, O. Corell, A. Vasiliev, G. Mazza, E. Antokhin, A. Gerasimov, Egle Tomasi-Gustafsson, J. Hofmann, R. Karabowicz, V.Kh. Dodokhov, A. E. Blinov, P.-E. Tegnér, Andrey Uzunian, S. Wolff, M. Steinen, L. Linzen, Y. Zhou, F. H. Heinsius, Zhengtai Liu, P. De Remigis, C. J. Schmidt, I. Lehmann, H. Denizli, H. Deppe, Ajay Kumar Rai, T. Johansson, T. Holtmann, A. G. Denig, V. Panjushkin, J. Frech, A. Hayrapetyan, W. Zhu, L. Nogach, E. Vishnevsky, D. Melnychuk, Q. Hu, I. Köseoglu, Andrea Bianconi, J. Pereira-de-Lira, A. Derevschikov, A. Belias, O. Malyshev, D. Miehling, Nicola Paone, K. Pysz, A. Ryazantsev, D. I. Glazier, G. Reicherz, R. Hagdorn, M. Strickert, M. Böhm, Chinorat Kobdaj, P. Brand, Vladimir Blinov, P. Wüstner, X. Y. Shen, Paolo Mengucci, Christoph Herold, M. Pelizäus, G. V. Fedotov, T. Nasawad, A. Dolgolenko, N. B. Skachkov, S. Pongampai, S. Coen, Y. Melnik, V. A. Matveev, U. Kurilla, V. Jary, B. Zwieglinski, F. Khalid, A. Gillitzer, D. Calvo, Andreas Martin Heinz, M. Kavatsyuk, Mariana Nanova, S. Belostotski, K. Nowakowski, Claude Amsler, T. Erlen, K. Kalita, M. Domagala, A. Derichs, Ulrich Wiedner, E. Prencipe, L. Brück, R. Schmitz, Antonin Kveton, V. Mochalov, A.S. Vodopianov, J. Kellers, J. Rieger, G. Huang, N. Wongprachanukul, Bo Cederwall, K. Götzen, A. N. Skachkova, Edward Lisowski, J. Pütz, U. Müller, C. Motzko, K.-T. Brinkmann, S.A. Kononov, Dirk Grunwald, G. Neue, U. Thoma, R. Lalik, A. Kantsyrev, S. Sun, M. Virius, B. Salisbury, J. Oppotsch, Jize Zhao, R. Dzhygadlo, T. Held, F. Nerling, G. D. Alexeev, M. Bölting, A. Boukharov, G. Golovanov, I. Zimmermann, N. Er, A. Malige, S. Godre, Ting Xiao, M. Wojciechowski, Ch. Schmidt, T. Simantathammakul, B. Seitz, P. Balanutsa, B. J. Liu, V. Crede, M. Krebs, E. Rosenthal, Y. K. Sun, D. G. Ireland, W. Kühn, V. Abramov, Z. Tavukoglu, Mikhail Korzhik, A. Kripko, S. Spataro, D. Bumrungkoh, V. M. Abazov, R. Schubert, H. Flemming, Vaclav Vrba, S. I. Manaenkov, S. Kegel, A. Lehmann, U. Keskin, Hans-Georg Zaunick, R. Kliemt, V. Uzhinsky, Karin Schönning, X. Zhou, R. Böhm, S. Maldaner, J. Moron, D. P. Watts, E.K. Koshurnikov, M. Slunecka, P. Poznański, M. Firlej, P. Srisawad, A. Yu. Barnyakov, D. Kazlou, M. Yu. Barabanov, J. Płażek, V. Chauhan, R. W. Novotny, S. Schlimme, C. Schwarz, Y. Goncharenko, Lennart Isaksson, P. Eugenio, Kamal K. Seth, Concettina Sfienti, Harald Merkel, H. Xu, A. Meschanin, Marek Idzik, Mario Bragadireanu, Kazem Azizi, M. Lattery, C. Yu, G. Perez-Andrade, G. Boca, C. Liu, A. Chlopik, Johann Marton, Jens Hartmann, A. Samartsev, M. O. Distler, Dan Pantea, W. Eyrich, P. Gianotti, J. Li, E. Ladygina, Michael Düren, M. Albrecht, M. Tomasek, J. Regina, Michaela Thiel, I. Shein, L. Capozza, V. Chernetsky, Y. A. Tikhonov, Oleg V. Missevitch, V. Lucherini, Lorenzo Scalise, Fabrizio Daví, J. Petersen, F. E. Maas, A. Filippi, Gianni Barucca, T. Wasem, J. Reher, J. Schwiening, P. Wintz, O. Korchak, M. Marcisovsky, Volker Metag, S. Zimmermann, N. Hüsken, S. Pankonin, P. Jiang, Antoni Szczurek, C. Schnier, H. Orth, S. Bukreeva, H. Loehner, S. Orfanitski, D. Lehmann, C. Mannweiler, V. Ferapontov, D. Y. Kirin, M. Moritz, C. Hahn, D. A. Morozov, J. Grochowski, A. A. Piskun, Hans Calén, Christoph Hanhart, S. Bodenschatz, J. Tarasiuk, Christian S. Fischer, M. Urban, G. Zhao, T. Sefzick, A. Demekhin, P. Wieczorek, Giovanni Lancioni, Daniel Duda, M. Hoek, A. Akram, S. Ryzhikov, Yu. Yu. Lobanov, E. A. Strokovsky, A. Galoyan, F. Feldbauer, S. Shimanski, A.A. Efremov, Paweł Moskal, H. Peng, G. Kesik, S. Schadmand, B. Kopf, G. Schepers, B. Krusche, J. G. Messchendorp, V. V. Tokmenin, K. Manasatitpong, A. Dbeyssi, M. Fritsch, Witold Przygoda, S. Poslavskiy, Valentino Rigato, A. Khoukaz, M. Kümmel, D. Klostermann, S. Koch, E. A. Kravchenko, M. Sachs, Ayut Limphirat, L. Tomasek, I. K. Keshk, D. Liu, P. P. Natali, A. Gerhardt, H. Qi, I. A. Kuyanov, Patrick Achenbach, Alexander Olshevskiy, W. Alkakhi, N. Kristi, H. H. Leithoff, N. I. Zhuravlev, P. Semenov, V. Rodin, Keval Gandhi, E. Maslova, Xi-Guang Cao, M. Traxler, Herbert Koch, A. Täschner, Grzegorz Korcyl, Krisztian Peters, P. Kulessa, Sinead M. Ryan, F. Schupp, Sean A Dobbs, J. Pochodzalla, M. Himmelreich, S. Chernichenko, O. Noll, T. Triffterer, F. Lisowski, P. Salabura, Krzysztof Swientek, Pawel Marciniewski, D. Veretennikov, W. Lauth, Xuan Zhang, I. Prochazka, D. Prasuhn, Johann Haidenbauer, S. Pflüger, W. Schäfer, A. Golubev, Tobias Stockmanns, S. Bleser, V. Serdyuk, M. Michałek, B. Ketzer, Jerzy Smyrski, S. Bökelmann, V. Freudenreich, A. Ehret, S. Wronka, R. Kappert, Andrey V. Izotov, M. Bukharova, E. Luschevskaya, K. Khosonthongkee, C. Wenzel, M. Pfaffinger, E. Pyata, Ch. Hammann, M. Steinke, A. Fechtchenko, L. Schmitt, Michael Papenbrock, N. Rathod, D. Wölbing, Richard Wheadon, U. Lynen, Andrea Lavagno, M.F.M. Lutz, Bernd Voss, B. Hetz, Daniele Rinaldi, Tomasz Fiutowski, V. Moiseev, Magnus Wolke, V. Varentsov, M. Schmidt, N. Minaev, A. Balashoff, Mohammed Al-Turany, Andrzej Kupsc, P. Orsich, M. Steinacher, M. Finger, I. Augustin, Mathias Fink, P. Terlecki, A. E. Yakutin, R. Beck, Krzysztof Korcyl, Gianangelo Bracco, R. Dosdall, and O. Miklukho

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Luminosity (scattering theory), 010308 nuclear & particles physics, Physics::Instrumentation and Detectors, Physics beyond the Standard Model, Hadron, Detector, Strong interaction, 01 natural sciences, Antiproton, 0103 physical sciences, Facility for Antiproton and Ion Research, 010306 general physics, Nuclear Experiment, Storage ring
Abstract

The Facility for Antiproton and Ion Research (FAIR) in Darmstadt, Germany, provides unique possibilities for a new generation of hadron-, nuclear- and atomic physics experiments. The future antiProton ANnihilations at DArmstadt (PANDA or $$\overline{\mathrm{P}}$$ P ¯ ANDA) experiment at FAIR will offer a broad physics programme, covering different aspects of the strong interaction. Understanding the latter in the non-perturbative regime remains one of the greatest challenges in contemporary physics. The antiproton–nucleon interaction studied with PANDA provides crucial tests in this area. Furthermore, the high-intensity, low-energy domain of PANDA allows for searches for physics beyond the Standard Model, e.g. through high precision symmetry tests. This paper takes into account a staged approach for the detector setup and for the delivered luminosity from the accelerator. The available detector setup at the time of the delivery of the first antiproton beams in the HESR storage ring is referred to as the Phase One setup. The physics programme that is achievable during Phase One is outlined in this paper.

Published
2021

5. Observation of the pη′ Cusp in the New Precise Beam Asymmetry Σ Data for γp→pη

Author

Cbelsa, F. Afzal, L Richter, S. Ciupka, U-G Meißner, V. Metag, W. Meyer, M. Grüner, K. Koop, T. Seifen, Lilian Witthauer, H. Kalinowsky, Matthew Lang, D. Piontek, N. Stausberg, M. Urban, I. V. Lopatin, A. V. Sarantsev, T. C. Jude, Frank Frommberger, M. Becker, B. Mitlasóczki, H. Schmieden, M. Dieterle, V. Sokhoyan, H. van Pee, D. E. Bayadilov, P. Klassen, K. Spieker, K. Nikonov, B. Krusche, A. B. Gridnev, Mariana Nanova, B. Salisbury, Wolfgang Hillert, J. Hannappel, C. Sowa, J. Hoff, E. Gutz, Ch. Honisch, J. Schultes, H. Dutz, G. Urff, Ch. Schmidt, Y. Wunderlich, Ulrich Wiedner, Frank Klein, V. Crede, U. Thoma, D. Elsner, S. Friedrich, A. Wilson, R. W. Novotny, Ph. Hoffmeister, A. Thiel, V. Novinskiy, P. Mahlberg, A. V. Anisovich, Francesco Messi, I. Keshelashvili, Ch. Wendel, F. Kalischewski, K.-T. Brinkmann, T. Triffterer, P. Kroenert, G. Reicherz, D. Walther, Jörg H. Müller, Jens Hartmann, D. Rönchen, T. Rostomyan, M. Gottschall, E. Blanke, D. Schaab, R. Beck, Ch. Hammann, A. Winnebeck, J. Müllers, Eberhard Klempt, and V. A. Nikonov

Subjects
Physics, Photon, Meson, media_common.quotation_subject, Partial wave analysis, Nuclear Theory, Solid angle, General Physics and Astronomy, Observable, Polarization (waves), 01 natural sciences, Asymmetry, Nuclear physics, 0103 physical sciences, Physics::Accelerator Physics, Nuclear Experiment, 010306 general physics, Nucleon, media_common
Abstract

Data on the beam asymmetry Σ in the photoproduction of η mesons off protons are reported for tagged photon energies from 1130 to 1790 MeV (mass range from W=1748 MeV to W=2045 MeV). The data cover the full solid angle that allows for a precise moment analysis. For the first time, a strong cusp effect in a polarization observable has been observed that is an effect of a branch-point singularity at the pη^{'} threshold [E_{γ}=1447 MeV (W=1896 MeV)]. The latest BnGa partial wave analysis includes the new beam asymmetry data and yields a strong indication for the N(1895)1/2^{-} nucleon resonance, demonstrating the importance of including all singularities for a correct determination of partial waves and resonance parameters.

Published
2020

6. New data on γ→p→→ηp with polarized photons and protons and their implications for N⁎ → Nη decays

Author

J. Müller, J. Hartmann, M. Grüner, F. Afzal, A.V. Anisovich, B. Bantes, D. Bayadilov, R. Beck, M. Becker, Y. Beloglazov, A. Berlin, M. Bichow, S. Böse, K.-T. Brinkmann, T. Challand, V. Crede, F. Dietz, M. Dieterle, P. Drexler, H. Dutz, H. Eberhardt, D. Elsner, R. Ewald, K. Fornet-Ponse, S. Friedrich, F. Frommberger, C. Funke, M. Gottschall, A. Gridnev, S. Goertz, E. Gutz, C. Hammann, V. Hannen, J. Hannappel, J. Herick, W. Hillert, P. Hoffmeister, C. Honisch, O. Jahn, T. Jude, I. Jaegle, A. Käser, D. Kaiser, H. Kalinowsky, F. Kalischewski, S. Kammer, I. Keshelashvili, P. Klassen, V. Kleber, F. Klein, E. Klempt, K. Koop, B. Krusche, M. Kube, M. Lang, I. Lopatin, Y. Maghrbi, P. Mahlberg, K. Makonyi, F. Messi, V. Metag, W. Meyer, J. Müllers, M. Nanova, V. Nikonov, D. Novinski, R. Novotny, D. Piontek, G. Reicherz, C. Rosenbaum, T. Rostomyan, B. Roth, A. Sarantsev, C. Schmidt, H. Schmieden, R. Schmitz, T. Seifen, V. Sokhoyan, A. Thiel, U. Thoma, M. Urban, H. van Pee, D. Walther, C. Wendel, U. Wiedner, A. Wilson, A. Winnebeck, and L. Witthauer

Subjects
Nuclear Theory, High Energy Physics::Experiment, Nuclear Experiment, lcsh:Physics, lcsh:QC1-999
Abstract

The polarization observables T,E,P,H, and G in photoproduction of η mesons off protons are measured for photon energies from threshold to W=2400 MeV (T), 2280 MeV (E), 1620 MeV (P,H), or 1820 MeV (G), covering nearly the full solid angle. The data are compared to predictions from the SAID, MAID, JüBo, and BnGa partial-wave analyses. A refit within the BnGa approach including further data yields precise branching ratios for the Nη decay of nucleon resonances. A Nη-branching ratio of 0.33±0.04 for N(1650)1/2− is found, which reduces the large and controversially discussed Nη-branching ratio difference of the two lowest mass JP=1/2−-resonances significantly. Keywords: Baryon spectroscopy, Meson photoproduction, Polarization observables

Published
2020

7. Observation of the p η ′ Cusp in the New Precise Beam Asymmetry Σ Data for γ p → p η

Author

F, Afzal, Y, Wunderlich, A V, Anisovich, D, Bayadilov, R, Beck, M, Becker, E, Blanke, K-Th, Brinkmann, S, Ciupka, V, Crede, M, Dieterle, H, Dutz, D, Elsner, S, Friedrich, F, Frommberger, A, Gridnev, M, Gottschall, M, Grüner, E, Gutz, C, Hammann, J, Hannappel, J, Hartmann, W, Hillert, J, Hoff, P, Hoffmeister, C, Honisch, T, Jude, H, Kalinowsky, F, Kalischewski, I, Keshelashvili, P, Klassen, F, Klein, E, Klempt, K, Koop, P, Kroenert, B, Krusche, M, Lang, I, Lopatin, P, Mahlberg, U-G, Meißner, F, Messi, V, Metag, W, Meyer, B, Mitlasóczki, J, Müller, J, Müllers, M, Nanova, K, Nikonov, V, Nikonov, V, Novinskiy, R, Novotny, D, Piontek, G, Reicherz, L, Richter, D, Rönchen, T, Rostomyan, B, Salisbury, A, Sarantsev, D, Schaab, C, Schmidt, H, Schmieden, J, Schultes, T, Seifen, V, Sokhoyan, C, Sowa, K, Spieker, N, Stausberg, A, Thiel, U, Thoma, T, Triffterer, M, Urban, G, Urff, H, van Pee, D, Walther, Ch, Wendel, U, Wiedner, A, Wilson, A, Winnebeck, and L, Witthauer

Subjects
Nuclear Theory, Physics::Accelerator Physics, ddc:530, Nuclear Experiment
Abstract

Data on the beam asymmetry Σ in the photoproduction of η mesons off protons are reported for tagged photon energies from 1130 to 1790 MeV (mass range from W=1748 MeV to W=2045 MeV). The data cover the full solid angle that allows for a precise moment analysis. For the first time, a strong cusp effect in a polarization observable has been observed that is an effect of a branch-point singularity at the pη^{'} threshold [E_{γ}=1447 MeV (W=1896 MeV)]. The latest BnGa partial wave analysis includes the new beam asymmetry data and yields a strong indication for the N(1895)1/2^{-} nucleon resonance, demonstrating the importance of including all singularities for a correct determination of partial waves and resonance parameters.

Published
2020

8. Proton-η′ interactions at threshold

Author

Michael Dugger, Barry Ritchie, A. V. Sarantsev, A. V. Anisovich, Volker D. Burkert, U. Thoma, V. A. Nikonov, and Eberhard Klempt

Subjects
Physics, Nuclear and High Energy Physics, Range (particle radiation), Meson, Proton, 010308 nuclear & particles physics, media_common.quotation_subject, Partial wave analysis, Nuclear Theory, Scattering length, 01 natural sciences, Asymmetry, Resonance (particle physics), lcsh:QC1-999, Scattering amplitude, 0103 physical sciences, Atomic physics, Nuclear Experiment, 010306 general physics, lcsh:Physics, media_common
Abstract

Recent data on photoproduction of η′ mesons off protons have been included in the data base for the Bonn–Gatchina partial wave analysis. The real and imaginary parts of the S-wave η′p→η′p scattering amplitude in the threshold region were fit to yield the η′p scattering length and the interaction range. This new analysis found |aη′p|=(0.403±0.015±0.060) fm and a phase ϕ=(87±2)∘, while the range parameter is not well-constrained. The striking behavior of the GRAAL data on the beam asymmetry in the threshold region suggests that a narrow proton-η′ resonance might exist. However, the scattering length was found to be relatively insensitive to the possible existence of this narrow resonance.

Published
2018

9. Hyperon I: Partial-wave amplitudes for K-p scattering

Author

V. A. Nikonov, A. V. Anisovich, M. A. Matveev, A. V. Sarantsev, U. Thoma, and Eberhard Klempt

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, 010308 nuclear & particles physics, Scattering, Hadron, Hyperon, FOS: Physical sciences, Resonance, Lambda, digestive system, 01 natural sciences, digestive system diseases, Amplitude, Hadron spectroscopy, 0103 physical sciences, Nuclear Experiment (nucl-ex), Nuclear Experiment, 010306 general physics, Legendre polynomials
Abstract

Early data on $K^-$ induced reactions off protons are collected and used in a coupled-channel partial wave analysis (PWA). Data which had been published in the form of Legendre coefficients are included in the PWA. In a {\it primary} fit using 3* and 4* resonances only, we observe some significant discrepancies with the data. In a systematic search for new $\Lambda$ and $\Sigma$ hyperon resonances, additional candidates are found. The significance of the known and of the additional resonances is evaluated. Seventeen resonances listed with 1* or 2* and one resonance listed with 3* in the Review of Particle Properties cannot be confirmed, five new hyperons are suggested. The partial-wave amplitudes deduced in this analysis are compared to those from other analyses., Comment: 28 pages, 27 figures, 9 Tables

Published
2019

10. Hyperon II: Properties of excited hyperons

Author

V. A. Nikonov, A. V. Sarantsev, M. A. Matveev, A. V. Anisovich, U. Thoma, and Eberhard Klempt

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Quark model, Hadron, Hyperon, FOS: Physical sciences, Lambda, Omega, Excited state, Mass spectrum, High Energy Physics::Experiment, Singlet state, Nuclear Experiment (nucl-ex), Nuclear Experiment
Abstract

We report properties of $\Lambda$ and $\Sigma$ hyperon resonances formed in $K^-$ induced reactions. Special emphasis is laid on the analysis of the three-body final states $2\pi^0\Lambda$ and $2\pi^0\Sigma$ and of the quasi-two-body final states $\pi\Lambda(1520)$, $\bar K\Delta(1232)$, $\pi\Sigma(1385)$, $\bar K^*N$, and $\omega\Lambda$. We give pole positions of $\Lambda$ and $\Sigma$ hyperon resonances and transition residues from the $K^-p$ initial to various final states as well as Breit-Wigner masses and widths and decay branching ratios. Twenty resonances and "bumps" reported in the Review of Particle Physics are not required in our fits, evidence for five new resonances is reported. The observed mass spectrum is compared to the spectrum calculated in the Bonn quark model. Three spin doublets, six $\Lambda$ hyperons, are tentatively assigned to the SU(3) singlet system., Comment: 18 pages, 10 Figures, 3 Tables

Published
2019

11. Technical design report for the $\overline{{\rm{P}}}\mathrm{ANDA}$ Barrel DIRC detector

Author

B Singh, W Erni, B Krusche, M Steinacher, N Walford, B Liu, H Liu, Z Liu, X Shen, C Wang, J Zhao, M Albrecht, T Erlen, F Feldbauer, M Fink, M Fritsch, J Haase, F H Heinsius, T Held, T Holtmann, I Keshk, H Koch, B Kopf, M Kuhlmann, M Kümmel, S Leiber, M Mikirtychyants, P Musiol, A Mustafa, M Pelizäus, A Pitka, J Pychy, M Richter, C Schnier, T Schröder, C Sowa, M Steinke, T Triffterer, U Wiedner, M Ball, R Beck, C Hammann, B Ketzer, M Kube, P Mahlberg, M Rossbach, C Schmidt, R Schmitz, U Thoma, M Urban, D Walther, C Wendel, A Wilson, A Bianconi, M Bragadireanu, D Pantea, B Patel, W Czyzycki, M Domagala, G Filo, J Jaworowski, M Krawczyk, E Lisowski, F Lisowski, M Michałek, P Poznański, J Płażek, K Korcyl, A Kozela, P Kulessa, P Lebiedowicz, K Pysz, W Schäfer, A Szczurek, T Fiutowski, M Idzik, B Mindur, K Swientek, J Biernat, B Kamys, S Kistryn, G Korcyl, W Krzemien, A Magiera, P Moskal, A Pyszniak, Z Rudy, P Salabura, J Smyrski, P Strzempek, A Wronska, I Augustin, R Böhm, I Lehmann, D Nicmorus Marinescu, L Schmitt, V Varentsov, A Ali, M Al-Turany, A Belias, H Deppe, N Divani Veis, R Dzhygadlo, H Flemming, A Gerhardt, K Götzen, A Gromliuk, L Gruber, R Hohler, G Kalicy, R Karabowicz, R Kliemt, M Krebs, U Kurilla, D Lehmann, S Löchner, J Lühning, U Lynen, F Nerling, H Orth, M Patsyuk, K Peters, T Saito, G Schepers, C J Schmidt, C Schwarz, J Schwiening, A Täschner, M Traxler, C Ugur, B Voss, P Wieczorek, A Wilms, M Zühlsdorf, V Abazov, G Alexeev, V A Arefiev, V Astakhov, M Yu Barabanov, B V Batyunya, Y Davydov, V Kh Dodokhov, A Efremov, A Fechtchenko, A G Fedunov, A Galoyan, S Grigoryan, E K Koshurnikov, Y Yu Lobanov, V I Lobanov, A F Makarov, L V Malinina, V Malyshev, A G Olshevskiy, E Perevalova, A A Piskun, T Pocheptsov, G Pontecorvo, V Rodionov, Y Rogov, R Salmin, A Samartsev, M G Sapozhnikov, G Shabratova, N B Skachkov, A N Skachkova, E A Strokovsky, M Suleimanov, R Teshev, V Tokmenin, V Uzhinsky, A Vodopianov, S A Zaporozhets, N I Zhuravlev, A Zinchenko, D Branford, D Glazier, D Watts, M Böhm, A Britting, W Eyrich, A Lehmann, M Pfaffinger, F Uhlig, S Dobbs, K Seth, A Tomaradze, T Xiao, D Bettoni, V Carassiti, A Cotta Ramusino, P Dalpiaz, A Drago, E Fioravanti, I Garzia, M Savrie, V Akishina, S Gorbunov, I Kisel, G Kozlov, M Pugach, M Zyzak, P Gianotti, C Guaraldo, V Lucherini, A Bersani, G Bracco, M Macri, R F Parodi, K Biguenko, K T Brinkmann, V Di Pietro, S Diehl, V Dormenev, M Düren, E Etzelmüller, K Föhl, M Galuska, E Gutz, C Hahn, A Hayrapetyan, M Kesselkaul, K Kreutzfeldt, W Kühn, T Kuske, J S Lange, Y Liang, V Metag, M Moritz, M Nanova, R Novotny, T Quagli, S Reiter, A Riccardi, J Rieke, C Rosenbaum, M Schmidt, R Schnell, H Stenzel, U Thöring, M N Wagner, T Wasem, B Wohlfahrt, H G Zaunick, E Tomasi-Gustafsson, D Ireland, G Rosner, B Seitz, P N Deepak, A Kulkarni, A Apostolou, M Babai, M Kavatsyuk, P J Lemmens, M Lindemulder, H Loehner, J Messchendorp, P Schakel, H Smit, M Tiemens, J C van der Weele, R Veenstra, S Vejdani, K Dutta, K Kalita, A Kumar, A Roy, H Sohlbach, M Bai, L Bianchi, M Büscher, L Cao, A Cebulla, R Dosdall, A Erven, V Fracassi, A Gillitzer, F Goldenbaum, D Grunwald, A Herten, Q Hu, L Jokhovets, G Kemmerling, H Kleines, A Lai, A Lehrach, R Nellen, H Ohm, S Orfanitski, D Prasuhn, E Prencipe, J Pütz, J Ritman, E Rosenthal, S Schadmand, T Sefzick, V Serdyuk, G Sterzenbach, T Stockmanns, P Wintz, P Wüstner, H Xu, S Li, Z Li, Z Sun, V Rigato, L Isaksson, P Achenbach, A Aycock, O Corell, A Denig, M Distler, M Hoek, A Karavdina, W Lauth, H Merkel, U Müller, J Pochodzalla, S Sanchez, S Schlimme, C Sfienti, M Thiel, H Ahmadi, null S Ahmed, S Bleser, L Capozza, M Cardinali, A Dbeyssi, M Deiseroth, A Ehret, B Fröhlich, D Kang, D Khaneft, R Klasen, H H Leithoff, D Lin, F Maas, S Maldaner, M Martínez, M Michel, M C Mora Espí, C Morales Morales, C Motzko, O Noll, S Pflüger, D Rodríguez Piñeiro, A Sanchez-Lorente, M Steinen, R Valente, M Zambrana, I Zimmermann, A Fedorov, M Korjik, O Missevitch, A Balashoff, A Boukharov, O Malyshev, I Marishev, P Balanutsa, V Balanutsa, V Chernetsky, A Demekhin, A Dolgolenko, P Fedorets, A Gerasimov, V Goryachev, V Chandratre, V Datar, D Dutta, V Jha, H Kumawat, A K Mohanty, A Parmar, A K Rai, B Roy, G Sonika, C Fritzsch, S Grieser, A K Hergemöller, B Hetz, N Hüsken, A Khoukaz, J P Wessels, K Khosonthongkee, C Kobdaj, A Limphirat, P Srisawad, Y Yan, E Antokhin, A Yu Barnyakov, M Barnyakov, K Beloborodov, V E Blinov, V S Bobrovnikov, I A Kuyanov, K Martin, A P Onuchin, S Pivovarov, E Pyata, S Serednyakov, A Sokolov, Y Tikhonov, A E Blinov, S Kononov, E A Kravchenko, E Atomssa, R Kunne, D Marchand, B Ramstein, J van de Wiele, Y Wang, G Boca, S Costanza, P Genova, P Montagna, A Rotondi, M Bodlak, M Finger, A Nikolovova, M Pesek, M Peskova, M Pfeffer, I Prochazka, M Slunecka, P Gallus, V Jary, J Novy, M Tomasek, M Virius, V Vrba, V Abramov, N Belikov, S Bukreeva, A Davidenko, A Derevschikov, Y Goncharenko, V Grishin, V Kachanov, V Kormilitsin, A Levin, Y Melnik, N Minaev, V Mochalov, D Morozov, L Nogach, S Poslavskiy, A Ryazantsev, S Ryzhikov, P Semenov, I Shein, A Uzunian, A Vasiliev, A Yakutin, U Roy, B Yabsley, S Belostotski, G Gavrilov, A Izotov, S Manaenkov, O Miklukho, D Veretennikov, A Zhdanov, K Makonyi, M Preston, P E Tegner, D Wölbing, T Bäck, B Cederwall, S Godre, F Balestra, F Iazzi, R Introzzi, A Lavagno, J Olave, A Amoroso, M P Bussa, L Busso, M Destefanis, L Fava, L Ferrero, M Greco, J Hu, L Lavezzi, M Maggiora, G Maniscalco, S Marcello, S Sosio, S Spataro, D Calvo, S Coli, P De Remigis, A Filippi, G Giraudo, S Lusso, G Mazza, M Mignone, A Rivetti, R Wheadon, R Birsa, F Bradamante, A Bressan, A Martin, H Calen, W Ikegami Andersson, T Johansson, A Kupsc, P Marciniewski, M Papenbrock, J Pettersson, K Schönning, M Wolke, B Galnander, J Diaz, V Pothodi Chackara, A Chlopik, G Kesik, D Melnychuk, B Slowinski, A Trzcinski, M Wojciechowski, S Wronka, B Zwieglinski, P Bühler, J Marton, D Steinschaden, K Suzuki, E Widmann, S Zimmermann, and J Zmeskal

Subjects
Physics, Nuclear and High Energy Physics, Range (particle radiation), Large Hadron Collider, Physics::Instrumentation and Detectors, 010308 nuclear & particles physics, Hadron, Detector, Barrel (horology), 7. Clean energy, 01 natural sciences, Ring-imaging Cherenkov detector, Particle identification, Charged particle, Nuclear physics, 0103 physical sciences, High Energy Physics::Experiment, ddc:530, 010306 general physics, Nuclear Experiment
Abstract

The $\overline{{\rm{P}}}\mathrm{ANDA}$ (anti-Proton ANnihiliation at DArmstadt) experiment will be one of the four flagship experiments at the new international accelerator complex FAIR (Facility for Antiproton and Ion Research) in Darmstadt, Germany. $\overline{{\rm{P}}}\mathrm{ANDA}$ will address fundamental questions of hadron physics and quantum chromodynamics using high-intensity cooled antiproton beams with momenta between 1.5 and 15 GeV/c and a design luminosity of up to 2 × 1032 cm−2 s−1. Excellent particle identification (PID) is crucial to the success of the $\overline{{\rm{P}}}\mathrm{ANDA}$ physics program. Hadronic PID in the barrel region of the target spectrometer will be performed by a fast and compact Cherenkov counter using the detection of internally reflected Cherenkov light (DIRC) technology. It is designed to cover the polar angle range from 22° to 140° and will provide at least 3 standard deviations (s.d.) π/K separation up to 3.5 GeV/c, matching the expected upper limit of the final state kaon momentum distribution from simulation. This documents describes the technical design and the expected performance of the $\overline{{\rm{P}}}\mathrm{ANDA}$ Barrel DIRC detector. The design is based on the successful BaBar DIRC with several key improvements. The performance and system cost were optimized in detailed detector simulations and validated with full system prototypes using particle beams at GSI and CERN. The final design meets or exceeds the PID goal of clean π/K separation with at least 3 s.d. over the entire phase space of charged kaons in the Barrel DIRC.

Published
2019

12. Study of doubly strange systems using stored antiprotons

Author

B. Singh, W. Erni, B. Krusche, M. Steinacher, N. Walford, B. Liu, H. Liu, Z. Liu, X. Shen, C. Wang, J. Zhao, M. Albrecht, T. Erlen, M. Fink, F. Heinsius, T. Held, T. Holtmann, S. Jasper, I. Keshk, H. Koch, B. Kopf, M. Kuhlmann, M. Kümmel, S. Leiber, M. Mikirtychyants, P. Musiol, A. Mustafa, M. Pelizäus, J. Pychy, M. Richter, C. Schnier, T. Schröder, C. Sowa, M. Steinke, T. Triffterer, U. Wiedner, M. Ball, R. Beck, C. Hammann, B. Ketzer, M. Kube, P. Mahlberg, M. Rossbach, C. Schmidt, R. Schmitz, U. Thoma, M. Urban, D. Walther, C. Wendel, A. Wilson, A. Bianconi, M. Bragadireanu, M. Caprini, D. Pantea, B. Patel, W. Czyzycki, M. Domagala, G. Filo, J. Jaworowski, M. Krawczyk, E. Lisowski, F. Lisowski, M. Michałek, P. Poznański, J. Płażek, K. Korcyl, A. Kozela, P. Kulessa, P. Lebiedowicz, K. Pysz, W. Schäfer, A. Szczurek, T. Fiutowski, M. Idzik, B. Mindur, D. Przyborowski, K. Swientek, J. Biernat, B. Kamys, S. Kistryn, G. Korcyl, W. Krzemien, A. Magiera, P. Moskal, A. Psyzniak, Z. Rudy, P. Salabura, J. Smyrski, P. Strzempek, A. Wronska, I. Augustin, R. Böhm, I. Lehmann, D. Nicmorus Marinescu, L. Schmitt, V. Varentsov, M. Al-Turany, A. Belias, H. Deppe, R. Dzhygadlo, A. Ehret, H. Flemming, A. Gerhardt, K. Götzen, A. Gromliuk, L. Gruber, R. Karabowicz, R. Kliemt, M. Krebs, U. Kurilla, D. Lehmann, S. Löchner, J. Lühning, U. Lynen, H. Orth, M. Patsyuk, K. Peters, T. Saito, G. Schepers, C.J. Schmidt, C. Schwarz, J. Schwiening, A. Täschner, M. Traxler, C. Ugur, B. Voss, P. Wieczorek, A. Wilms, M. Zühlsdorf, V.M. Abazov, G. Alexeev, A. Arefiev, V.I. Astakhov, M.Yu. Barabanov, B.V. Batyunya, Yu.I. Davydov, V.Kh. Dodokhov, A.A. Efremov, A. Fechtchenko, A.G. Fedunov, A. Galoyan, S. Grigoryan, E.K. Koshurnikov, V.I. Lobanov, Y.Yu. Lobanov, A.F. Makarov, L.V. Malinina, V.L. Malyshev, A. Olshevskiy, E. Perevalova, A.A. Piskun, T. Pocheptsov, G. Pontecorvo, V. Rodionov, Y. Rogov, R. Salmin, A. Samartsev, M.G. Sapozhnikov, G. Shabratova, N.B. Skachkov, A.N. Skachkova, E.A. Strokovsky, M. Suleimanov, R. Teshev, V. Tokmenin, V. Uzhinsky, A. Vodopyanov, S.A. Zaporozhets, N.I. Zhuravlev, A.G. Zorin, D. Branford, D. Glazier, D. Watts, M. Böhm, A. Britting, W. Eyrich, A. Lehmann, M. Pfaffinger, F. Uhlig, S. Dobbs, K. Seth, A. Tomaradze, T. Xiao, D. Bettoni, V. Carassiti, A. Cotta Ramusino, P. Dalpiaz, A. Drago, E. Fioravanti, I. Garzia, M. Savriè, V. Akishina, I. Kisel, G. Kozlov, M. Pugach, M. Zyzak, P. Gianotti, C. Guaraldo, V. Lucherini, A. Bersani, G. Bracco, M. Macri, R.F. Parodi, K. Biguenko, K. Brinkmann, V. Di Pietro, S. Diehl, V. Dormenev, P. Drexler, M. Düren, E. Etzelmüller, M. Galuska, E. Gutz, C. Hahn, A. Hayrapetyan, M. Kesselkaul, W. Kühn, T. Kuske, J.S. Lange, Y. Liang, V. Metag, M. Nanova, S. Nazarenko, R. Novotny, T. Quagli, S. Reiter, J. Rieke, C. Rosenbaum, M. Schmidt, R. Schnell, H. Stenzel, U. Thöring, M. Ullrich, M.N. Wagner, T. Wasem, B. Wohlfarth, H. Zaunick, D. Ireland, G. Rosner, B. Seitz, P.N. Deepak, A. Kulkarni, A. Apostolou, M. Babai, M. Kavatsyuk, P. Lemmens, M. Lindemulder, H. Loehner, J. Messchendorp, P. Schakel, H. Smit, M. Tiemens, J.C. van der Weele, R. Veenstra, S. Vejdani, K. Dutta, K. Kalita, A. Kumar, A. Roy, H. Sohlbach, M. Bai, L. Bianchi, M. Büscher, L. Cao, A. Cebulla, R. Dosdall, A. Gillitzer, F. Goldenbaum, D. Grunwald, A. Herten, Q. Hu, G. Kemmerling, H. Kleines, A. Lehrach, R. Nellen, H. Ohm, S. Orfanitski, D. Prasuhn, E. Prencipe, J. Pütz, J. Ritman, S. Schadmand, T. Sefzick, V. Serdyuk, G. Sterzenbach, T. Stockmanns, P. Wintz, P. Wüstner, H. Xu, A. Zambanini, S. Li, Z. Li, Z. Sun, V. Rigato, L. Isaksson, P. Achenbach, O. Corell, A. Denig, M. Distler, M. Hoek, A. Karavdina, W. Lauth, H. Merkel, U. Müller, J. Pochodzalla, S. Schlimme, C. Sfienti, M. Thiel, H. Ahmadi, S. Ahmed, S. Bleser, L. Capozza, M. Cardinali, A. Dbeyssi, M. Deiseroth, F. Feldbauer, M. Fritsch, B. Fröhlich, P. Jasinski, D. Kang, D. Khaneft, R. Klasen, H.H. Leithoff, D. Lin, F. Maas, S. Maldaner, M. Martìnez Rojo, M. Marta, M. Michel, M.C. Mora Espì, C. Morales Morales, C. Motzko, F. Nerling, O. Noll, S. Pflüger, A. Pitka, D. Rodríguez Piñeiro, A. Sanchez Lorente, M. Steinen, R. Valente, T. Weber, M. Zambrana, I. Zimmermann, A. Fedorov, M. Korjik, O. Missevitch, A. Boukharov, O. Malyshev, I. Marishev, P. Balanutsa, V. Balanutsa, V. Chernetsky, A. Demekhin, A. Dolgolenko, P. Fedorets, A. Gerasimov, V. Goryachev, V. Chandratre, V. Datar, D. Dutta, V. Jha, H. Kumawat, A.K. Mohanty, A. Parmar, B. Roy, G. Sonika, C. Fritzsch, S. Grieser, A.K. Hergemöller, B. Hetz, N. Hüsken, A. Khoukaz, J.P. Wessels, K. Khosonthongkee, C. Kobdaj, A. Limphirat, P. Srisawad, Y. Yan, M. Barnyakov, A.Yu. Barnyakov, K. Beloborodov, A.E. Blinov, V.E. Blinov, V.S. Bobrovnikov, S. Kononov, E.A. Kravchenko, I.A. Kuyanov, K. Martin, A.P. Onuchin, S. Serednyakov, A. Sokolov, Y. Tikhonov, E. Atomssa, R. Kunne, D. Marchand, B. Ramstein, J. Van de Wiele, Y. Wang, G. Boca, S. Costanza, P. Genova, P. Montagna, A. Rotondi, V. Abramov, N. Belikov, S. Bukreeva, A. Davidenko, A. Derevschikov, Y. Goncharenko, V. Grishin, V. Kachanov, V. Kormilitsin, A. Levin, Y. Melnik, N. Minaev, V. Mochalov, D. Morozov, L. Nogach, S. Poslavskiy, A. Ryazantsev, S. Ryzhikov, P. Semenov, I. Shein, A. Uzunian, A. Vasiliev, A. Yakutin, E. Tomasi-Gustafsson, U. Roy, B. Yabsley, S. Belostotski, G. Gavrilov, A. Izotov, S. Manaenkov, O. Miklukho, D. Veretennikov, A. Zhdanov, K. Makonyi, M. Preston, P. Tegner, D. Wölbing, T. Bäck, B. Cederwall, A.K. Rai, S. Godre, D. Calvo, S. Coli, P. De Remigis, A. Filippi, G. Giraudo, S. Lusso, G. Mazza, M. Mignone, A. Rivetti, R. Wheadon, F. Balestra, F. Iazzi, R. Introzzi, A. Lavagno, J. Olave, A. Amoroso, M.P. Bussa, L. Busso, F. De Mori, M. Destefanis, L. Fava, L. Ferrero, M. Greco, J. Hu, L. Lavezzi, M. Maggiora, G. Maniscalco, S. Marcello, S. Sosio, S. Spataro, R. Birsa, F. Bradamante, A. Bressan, A. Martin, H. Calen, W. Ikegami Andersson, T. Johansson, A. Kupsc, P. Marciniewski, M. Papenbrock, J. Pettersson, K. Schönning, M. Wolke, B. Galnander, J. Diaz, V. Pothodi Chackara, A. Chlopik, G. Kesik, D. Melnychuk, B. Slowinski, A. Trzcinski, M. Wojciechowski, S. Wronka, B. Zwieglinski, P. Bühler, J. Marton, D. Steinschaden, K. Suzuki, E. Widmann, J. Zmeskal, Jürgen Gerl, Ivan Kojouharov, Jasmina Kojouharova, and Research unit Nuclear & Hadron Physics

Subjects
Particle physics, Nuclear and High Energy Physics, COLLISIONS, Strong interaction, Nuclear Theory, hyperatoms, Antiprotons, Hyperatoms, Hypernuclei, Strangeness, EXCHANGE CURRENTS, 01 natural sciences, Partícules (Física nuclear), NO, Nuclear physics, Subatomär fysik, Hypemuclei, strangeness, DECUPLET BARYONS, ELECTRIC QUADRUPOLE-MOMENTS, 0103 physical sciences, Subatomic Physics, 010306 general physics, Nuclear Experiment, Physics, hypernuclei, NUCLEI, 010308 nuclear & particles physics, Hyperon, Transport theory, DOUBLE-LAMBDA-HYPERNUCLEI, MODEL, OMEGA, Antiproton, Physics::Accelerator Physics, Heavy ion, High Energy Physics::Experiment, antiprotons, INTERMEDIATE ENERGIES, EMULSION
Abstract

Bound nuclear systems with two units of strangeness are still poorly known despite their importance for many strong interaction phenomena. Stored antiprotons beams in the GeV range represent an unparalleled factory for various hyperon-antihyperon pairs. Their outstanding large production probability in antiproton collisions will open the floodgates for a series of new studies of systems which contain two or even more units of strangeness at the PANDA experiment at FAIR. For the first time, high resolution gamma-spectroscopy of doubly strange Lambda Lambda-hypernuclei will be performed, thus complementing measurements of ground state decays of Lambda Lambda-hypernuclei at J-PARC or possible decays of particle unstable hypernuclei in heavy ion reactions. High resolution spectroscopy of multistrange Xi(-) -atoms will be feasible and even the production of Omega(-) -atoms will be within reach. The latter might open the door to the vertical bar S vertical bar = 3 world in strangeness nuclear physics, by the study of the hadronic Omega(-) -nucleus interaction. For the first time it will be possible to study the behavior of Xi(+) in nuclear systems under well controlled conditions. (C) 2016 Elsevier B.V. All rights reserved.

Published
2016

13. N⁎ decays to Nω from new data on γp→ωp

Author

H. Schmieden, A. V. Sarantsev, U. Thoma, V. Crede, A. V. Anisovich, H. Eberhardt, A. Wilson, Eberhard Klempt, V. A. Nikonov, and I. Denisenko

Subjects
Physics, Nuclear and High Energy Physics, Photon, 010308 nuclear & particles physics, media_common.quotation_subject, Partial wave analysis, Polarization (waves), 7. Clean energy, 01 natural sciences, Asymmetry, Helicity, lcsh:QC1-999, Nuclear physics, Pion, 0103 physical sciences, Spin density, 010306 general physics, Nuclear Experiment, Beam (structure), lcsh:Physics, media_common
Abstract

Data on the reaction γ p → ω p with ω → π 0 γ , taken with unpolarized or polarized beams in combination with an unpolarized or polarized proton-target, were analyzed within the Bonn–Gatchina (BnGa) partial wave analysis. Differential cross sections, several spin density matrix elements, the beam asymmetry Σ, the normalized helicity difference E, and the correlation G between linear photon and longitudinal target polarization were included in a large data base on pion and photo-induced reactions. The data on ω photoproduction are used to determine twelve N ⁎ → N ω branching ratios; most of these are determined for the first time.

Published
2016
Full Text
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14. Resonances in QCD

Author

Stephen Lars Olsen, A. Gillitzer, Michael R. Pennington, Nora Brambilla, J. Ritman, Takashi Nakano, Volker Metag, E. Prencipe, Diego Bettoni, Christian B. Lang, Sebastian Neubert, M.F.M. Lutz, V. Crede, Alessandro Pilloni, Wolfram Weise, Wolfgang Gradl, Stephan Paul, U. Thoma, U. Uwer, Marco Pappagallo, Juan Nieves, Sinead M. Ryan, Jens Sören Lange, S.I. Eidelman, Marc Pelizäus, and Makoto Oka

Subjects
Physics, Quark, Quantum chromodynamics, Nuclear and High Energy Physics, Strange quark, Particle physics, Meson, 010308 nuclear & particles physics, High Energy Physics::Lattice, Nuclear Theory, High Energy Physics::Phenomenology, Hadron, 01 natural sciences, Charm quark, Baryon, High Energy Physics - Phenomenology, 0103 physical sciences, Hadrons, Mini review, QCD, Resonances, ddc:530, High Energy Physics::Experiment, Charm (quantum number), Nuclear Experiment, 010306 general physics
Abstract

We report on the EMMI Rapid Reaction Task Force meeting 'Resonances in QCD', which took place at GSI October 12-14, 2015. A group of 26 people met to discuss the physics of resonances in QCD. The aim of the meeting was defined by the following three key questions: What is needed to understand the physics of resonances in QCD? Where does QCD lead us to expect resonances with exotic quantum numbers? What experimental efforts are required to arrive at a coherent picture? For light mesons and baryons only those with ${\it up}$, ${\it down}$ and ${\it strange}$ quark content were considered. For heavy-light and heavy-heavy meson systems, those with ${\it charm}$ quarks were the focus. This document summarizes the discussions by the participants, which in turn led to the coherent conclusions we present here., Comment: 20 pages, 1 figure, report on the EMMI Rapid Reaction Task Force meeting '{\it Resonances in QCD}', which took place at GSI October 12-14, 2015

Published
2016

15. The $\eta^{\prime}$ η -carbon potential at low meson momenta

Author

D. Elsner, K. Koop, Frank Frommberger, V. Metag, Ph. Hoffmeister, J. Müller, B. Krusche, E. Gutz, D. Kaiser, K.-T. Brinkmann, T. Triffterer, C. Sowa, J. Müllers, A. Wilson, S. Friedrich, T. Seifen, Matthew Lang, J. Hannappel, B. Bantes, Francesco Messi, Ulrich Wiedner, E. Ya. Paryev, U. Thoma, D. Walther, Jens Hartmann, F. Afzal, Ch. Hammann, Reinhard Beck, P. Drexler, V. Crede, Ch. Honisch, Y. Wunderlich, D. Piontek, Ch. Schmidt, Hans-Georg Zaunick, H. Eberhardt, T. C. Jude, M. Becker, Ch. Funke, Ch. Wendel, D. Werthmüller, Wolfgang Hillert, M. Grüner, I. Keshelashvili, T. Rostomyan, Lilian Witthauer, M. Gottschall, S. Böse, K. Makonyi, M. Urban, V. Sokhoyan, H. van Pee, Friedrich Klein, K. Spieker, D. Schaab, R. Schmitz, A. Thiel, F. Kalischewski, H. Schmieden, D. E. Bayadilov, and Mariana Nanova

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Meson, 010308 nuclear & particles physics, Hadron, Carbon-12, Elementary particle, 01 natural sciences, Baryon, 0103 physical sciences, High Energy Physics::Experiment, Production (computer science), Nuclear Experiment, 010306 general physics, Nucleon, Boson
Abstract

The production of $\eta^{\prime}$ mesons in coincidence with forward-going protons has been studied in photon-induced reactions on 12C and on a liquid hydrogen (LH2) target for incoming photon energies of 1.3-2.6 GeV at the electron accelerator ELSA. The $\eta^{\prime}$ mesons have been identified via the $\eta^{\prime} \rightarrow \pi^{0} \pi^{0}\eta \rightarrow 6 \gamma$ decay registered with the CBELSA/TAPS detector system. Coincident protons have been identified in the MiniTAPS BaF2 array at polar angles of $2^{\circ} \le \theta_{p} \le 11^{\circ}$ . Under these kinematic constraints the $\eta^{\prime}$ mesons are produced with relatively low kinetic energy ( $\approx 150$ MeV) since the coincident protons take over most of the momentum of the incident-photon beam. For the C-target this allows the determination of the real part of the $\eta^{\prime}$ -carbon potential at low meson momenta by comparing with collision model calculations of the $\eta^{\prime}$ kinetic energy distribution and excitation function. Fitting the latter data for $\eta^{\prime}$ mesons going backwards in the center-of-mass system yields a potential depth of $V = -(44 \pm 16(stat) \pm 15(syst))$ MeV, consistent with earlier determinations of the potential depth in inclusive measurements for average $\eta^{\prime}$ momenta of $\approx 1.1$ GeV/c. Within the experimental uncertainties, there is no indication of a momentum dependence of the $\eta^{\prime}$ -carbon potential. The LH2 data, taken as a reference to check the data analysis and the model calculations, provide differential and integral cross sections in good agreement with previous results for $\eta^{\prime}$ photoproduction off the free proton.

Published
2018

16. Photoproduction of $ \eta{^\prime}$ -mesons off the deuteron

Author

S. Lugert, D. Walther, S. Hoeffgen, D. Trnka, I. Jaegle, M. Ostrick, Eberhard Klempt, A. V. Anisovich, Matthew Lang, U. Thoma, Kanzo Nakayama, T. Szczepanek, D. Menze, V. Metag, J. Junkersfeld, Fei Huang, V. Kleber, Wolfgang Hillert, V. Crede, H. Loehner, H. van Pee, Yu. A. Beloglazov, A. V. Sarantsev, T. Mertens, D. V. Novinski, S. Kammer, J. C. S. Bacelar, R. Gregor, R. Castelijns, V. A. Nikonov, M. Kotulla, C. Funke, L. Tiator, R. Ewald, O. Bartholomy, D. Elsner, Lalit Mohan Pant, R. Varma, Friedrich Klein, H. Dutz, Ch. Wendel, B. Krusche, Ch. Schmidt, R. W. Novotny, A. Suele, V. V. Sumachev, J. G. Messchendorp, S. Shende, B. Schoch, A. Fix, H. Kalinowsky, V. Sokhoyan, I. V. Lopatin, H. Schmieden, D. E. Bayadilov, A. B. Gridnev, Mariana Nanova, R. Beck, S. Schadmand, Ankhi Roy, E. Gutz, B. Bantes, Frank Frommberger, Frank Klein, and M. Pfeiffer

Subjects
Physics, Nuclear and High Energy Physics, Photon, Proton, Meson, Nuclear Theory, Particle accelerator, law.invention, Nuclear physics, Recoil, Deuterium, law, Neutron, High Energy Physics::Experiment, Nucleon, Nuclear Experiment
Abstract

Quasi-free photoproduction of $ \eta{^\prime}$ -mesons off nucleons bound in the deuteron has been measured with the combined Crystal Barrel - TAPS detector. The experiment was done at a tagged photon beam of the ELSA electron accelerator in Bonn for incident photon energies from the production threshold up to 2.5GeV. The $ \eta{^\prime}$ -mesons have been detected in coincidence with recoil protons and recoil neutrons. The quasi-free proton data are in good agreement with the results for free protons, indicating that nuclear effects have no significant impact. The coincidence with recoil neutrons provides the first data for the $ \gamma$ n $ \rightarrow$ n $ \eta{^\prime}$ reaction. In addition, also first estimates for coherent $ \eta{^\prime}$ -production off the deuteron have been obtained. In agreement with model predictions, the total cross-section for this channel is found to be very small, at most at the level of a few nb. The data are compared to model calculations taking into account contributions from nucleon resonances and t -channel exchanges

Published
2018

17. Photoproduction of η -mesons off nuclei for Eγ ⩽ 2.2 GeV

Author

Lalit Mohan Pant, B. Bantes, M. Pfeiffer, D. Menze, R. Ewald, S. Hoeffgen, Ankhi Roy, Ch. Wendel, V. V. Sumachev, H. Kalinowsky, Matthew Lang, A. Ehmanns, R. Varma, D. Elsner, I. Jaegle, S. Kammer, R. Castelijns, H. Dutz, S. Shende, V. Sokhoyan, S. Lugert, D. Trnka, B. Krusche, R. W. Novotny, Ph. Hoffmeister, K. Essig, J. Langheinrich, T. Szczepanek, A. Suele, O. Bartholomy, S. Schadmand, Ulrich Mosel, R. Gregor, Yu. A. Beloglazov, M. Konrad, R. W. Gothe, Eberhard Klempt, J. C. S. Bacelar, M. Kotulla, C.-H. Weinheimer, B. Schoch, C. Morales, M. Ostrick, I. Fabry, Michael Fuchs, R. Beck, E. Gutz, J. Lotz, V. Metag, V. Crede, Ch. Schmidt, Frank Klein, Friedrich Klein, V. Kleber, H. Schmieden, I. V. Lopatin, D. E. Bayadilov, A. B. Gridnev, Mariana Nanova, H. van Pee, D. V. Novinski, J. G. Messchendorp, K. Fornet-Ponse, D. Walther, C. Funke, I. Horn, A. Radkov, T. Mertens, U. Thoma, P. Muehlich, J. Junkersfeld, and H. Loehner

Subjects
Mass number, Physics, Nuclear and High Energy Physics, Meson, Nuclear Theory, Nuclear matter, Resonance (particle physics), Nuclear physics, Pion, Production (computer science), High Energy Physics::Experiment, Absorption (logic), Nucleon, Nuclear Experiment
Abstract

Photoproduction of $\eta$ mesons off $^{12}$C, $^{40}$Ca, $^{93}$Nb, and $^{nat}$Pb nuclei has been measured with a tagged photon beam with energies between 0.6 and 2.2 GeV. The experiment was performed at the Bonn ELSA accelerator with the combined setup of the Crystal Barrel and TAPS calorimeters. It aimed at the in-medium properties of the S$_{11}$(1535) nucleon resonance and the study of the absorption properties of nuclear matter for $\eta$ mesons. Careful consideration was given to contributions from $\eta\pi$ final states and secondary production mechanisms of $\eta$-mesons e.g. from inelastic $\pi N$ reactions of intermediate pions. The analysis of the mass number scaling shows that the nuclear absorption cross section $\sigma_{N\eta}$ for $\eta$ mesons is constant over a wide range of the $\eta$ momentum. The comparison of the excitation functions to data off the deuteron and to calculations in the framework of a BUU-model show no unexplained in-medium modifications of the S$_{11}$(1535)., Comment: Accepted for publication in Eur. Phys. J. A

Published
2018

18. N* resonances from K $\Lambda$ Λ amplitudes in sliced bins in energy

Author

D. G. Ireland, Volker D. Burkert, Eberhard Klempt, J. Stahov, R. Omerović, V. A. Nikonov, Alfred Švarc, M. Hadžimehmedović, U. Thoma, A. V. Sarantsev, and A. V. Anisovich

Subjects
Physics, Nuclear and High Energy Physics, 010308 nuclear & particles physics, Hadron, Quantum number, 7. Clean energy, 01 natural sciences, Riemann hypothesis, symbols.namesake, Amplitude, 0103 physical sciences, symbols, Invariant mass, Nuclear Experiment, 010306 general physics, Nucleon, Multipole expansion, Energy (signal processing), Mathematical physics
Abstract

The two reactions $\gamma p\to K^+\Lambda$ and $\pi^-p\to K^0\Lambda$ are analyzed to determine the leading photoproduction multipoles and the pion-induced partial wave amplitudes in slices of the invariant mass. The multipoles and the partial-wave amplitudes are simultaneously fitted in a multichannel Laurent+Pietarinen model (L+P model), which determines the poles in the complex energy plane on the second Riemann sheet close to the physical axes. The results from the L+P fit are compared with the results of an energy-dependent fit based on the Bonn-Gatchina (BnGa) approach. The study confirms the existence of several poles due to nucleon resonances in the region at about 1.9\,GeV with quantum numbers $J^P = 1/2^+$, $3/2^+, 1/2^-, 3/2^-, 5/2^-$., Comment: 18 pages, 12 figures

Published
2017

19. Measurement of double polarisation asymmetries in ω -photoproduction

Author

Frank Frommberger, V. Metag, F. Diez, M. Bichow, Ch. Hammann, T. Seifen, I. Jaegle, F. Kalischewski, D. Elsner, M. Kube, V. Crede, P. Drexler, A. Winnebeck, K. Fornet-Ponse, H. Schmieden, J. Müller, R. W. Novotny, B. Bantes, D. Walther, Ph. Hoffmeister, D. E. Bayadilov, K. Koop, U. Thoma, A. B. Gridnev, Mariana Nanova, S. Böse, A. Wilson, Yasser Maghrbi, H. Kalinowsky, Eberhard Klempt, H. Dutz, J. Hannappel, S. Runkel, H. Eberhardt, R. Ewald, Ulrich Wiedner, W. Meyer, St. Schaepe, V. A. Nikonov, T. Rostomyan, I. Keshelashvili, R. Schmitz, B. Krusche, Ch. Honisch, M. Grüner, Ch. Schmidt, A. Thiel, S. Friedrich, G. Reicherz, M. Gottschall, Friedrich Klein, Ch. Wendel, V. V. Sumachev, Wolfgang Hillert, R. Beck, Jens Hartmann, E. Gutz, S. Kammer, Th. Challand, Ch. Funke, K. Makonyi, Matthew Lang, K.-Th. Brinkmann, D. Kaiser, S. Reeve, H. van Pee, V. Kleber, D. Piontek, I. V. Lopatin, T. C. Jude, Yu. A. Beloglazov, A. V. Sarantsev, A. V. Anisovich, M. Urban, and V. Sokhoyan

Subjects
Physics, Nuclear and High Energy Physics, Photon, Meson, Partial wave analysis, Meson production, Resonance, Photon energy, Helicity, Omega, lcsh:QC1-999, Light mesons (SCB0), Nuclear physics, Baryon, Polarisation in interactions and scattering, Light mesons (SCB0), Nuclear Experiment, lcsh:Physics
Abstract

The first measurements of the beam-target-helicity-asymmetries $E$ and $G$ in the photoproduction of $\omega$-mesons off protons at the CBELSA/TAPS experiment are reported. $E$ ($G$) was measured using circularly (linearly) polarised photons and a longitudinally polarised target. $E$ was measured over the photon energy range from close to threshold ($E_\gamma = 1108$~MeV) to $E_\gamma = 2300$~MeV and $G$ at a single energy interval of $1108 < E_\gamma, Comment: 6 pages, 6 figures

Published
2015
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20. The polarization observables T , P , and H and their impact onγp→pπ0multipoles

Author

Ph. Thämer, Reinhard Beck, M. Grüner, V. Hannen, Matthew Lang, J. Herick, B. Roth, Ch. Honisch, Ch. Schmidt, K. Makonyi, K.-Th. Brinkmann, S. Reeve, H. van Pee, Eberhard Klempt, D. V. Novinski, Yu. A. Beloglazov, D. Elsner, M. Becker, Ch. Wendel, V. Crede, A. V. Sarantsev, S. Friedrich, W. Meyer, V. Metag, F. Kalischewski, Francesco Messi, R. W. Novotny, B. Krusche, Ph. Hoffmeister, St. Goertz, Lilian Witthauer, A. Käser, V. A. Nikonov, D. Piontek, I. V. Lopatin, A. V. Anisovich, J. Hannappel, P. Klassen, T. C. Jude, M. Urban, M. Dieterle, Ulrich Wiedner, V. Sokhoyan, A. Thiel, U. Thoma, Ch. Funke, Wolfgang Hillert, M. Bichow, H. Schmieden, D. E. Bayadilov, A. B. Gridnev, Mariana Nanova, K. Fornet-Ponse, S. Böse, Ch. Hammann, H. Kalinowsky, D. Walther, A. Winnebeck, A. Wilson, T. Seifen, Frank Frommberger, M. Kube, K. Koop, G. Reicherz, Friedrich Klein, R. Schmitz, O. Jahn, J. Müller, Ch. Rosenbaum, H. Dutz, H. Eberhardt, E. Gutz, I. Keshelashvili, St. Runkel, A. Berlin, T. Rostomyan, D. Kaiser, M. Gottschall, and Jens Hartmann

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Photon, Linear polarization, media_common.quotation_subject, Partial wave analysis, Electron, Polarization (waves), Asymmetry, Nuclear physics, Nuclear Experiment, Nucleon, Multipole expansion, media_common
Abstract

Data on the polarization observables T, P, and H for the reaction gamma p -> p pi(0) are reported. Compared to earlier data from other experiments, our data are more precise and extend the covered range in energy and angle substantially. The results were extracted from azimuthal asymmetries measured using a transversely polarized target and linearly polarized photons. The data were taken at the Bonn electron stretcher accelerator ELSA with the CBELSA/TAPS detector. Within the Bonn-Gatchina partial wave analysis, the new polarization data lead to a significant narrowing of the error band for the multipoles for neutral-pion photoproduction. (C) 2015 The Authors. Published by Elsevier B.V.

Published
2015

21. Neutron helicity amplitudes

Author

N. Compton, A. V. Sarantsev, Friedrich Klein, A. V. Anisovich, E. Klempt, K. Hicks, V. A. Nikonov, Volker D. Burkert, U. Thoma, and A. M. Sandorfi

Subjects
Physics, Particle physics, 010308 nuclear & particles physics, Partial wave analysis, Nuclear Theory, Lambda, 01 natural sciences, Helicity, Pentaquark, Nuclear physics, Excited state, 0103 physical sciences, Content (measure theory), High Energy Physics::Experiment, Neutron, Nuclear Experiment, 010306 general physics, Nucleon
Abstract

The helicity amplitudes for the photoproduction of nucleon resonances excited from neutrons are determined in the Bonn-Gatchina coupled-channel partial wave analysis. Upper limits for the decay fraction of the pentaquark candidate $N(1685)\ensuremath{\rightarrow}{K}^{0}\mathrm{\ensuremath{\Lambda}}$ are given. The electric and magnetic couplings at the pole positions are also tabulated, and these are used to suggest candidates for possible multiplets with quark-spin-1/2 and -3/2 content.

Published
2017

22. Scrutinizing the evidence for N(1685)

Author

Volker D. Burkert, U. Thoma, A. V. Anisovich, A. V. Sarantsev, V. A. Nikonov, and Eberhard Klempt

Subjects
Physics, Particle physics, 010308 nuclear & particles physics, 0103 physical sciences, Parity (physics), Observable, Nuclear Experiment, 010306 general physics, 01 natural sciences
Abstract

The helicity-dependent observable $E$ for the reaction $\ensuremath{\gamma}d\ensuremath{\rightarrow}\ensuremath{\eta}n(p)$ with a spectator proton was recently measured by the A2 Collaboration at MAMI in Mainz. The data were interpreted as further evidence for a narrow resonance with spin and parity ${J}^{P}=1/{2}^{+}$ $({P}_{11}$ wave). However, a full partial-wave analysis without any narrow resonance leads to an excellent description of the data. Imposing a narrow resonance with the properties suggested by the A2 Collaboration leads to a significant deterioration of the fit quality: there is no need for a narrow resonance.

Published
2017

23. Photoproduction of eta mesons from the neutron: cross sections and double polarization observable E

Author

Ch. Hammann, V. Metag, A. Winnebeck, M. Grüner, Wolfgang Hillert, T. Seifen, J. Müllers, T. Rostomyan, A. V. Anisovich, M. Gottschall, Frank Klein, K. Koop, Friedrich, M. Bichow, D. Elsner, B. Bantes, Jörg H. Müller, D. Piontek, M. Dieterle, Frank Frommberger, I. V. Lopatin, Jens Hartmann, V. Crede, R. Beck, Alastair J. Wilson, T. C. Jude, Ph. Hoffmeister, Suvadeep Bose, V. A. Nikonov, A. V. Sarantsev, E. Gutzınst, Ch. Honisch, Ch. Schmidt, B. Krusche, N. K. Walford, V. Kleber, Lilian Witthauer, D. Hammann, A. Käser, P. Klassen, K. Makonyi, Matthew Lang, H. van Pee, F. Kalischewski, D. Kaiser, S. Kammer, H. Schmieden, D. E. Bayadilov, H. Dutz, A. B. Gridnev, Mariana Nanova, Th. Challand, Ch. Funke, H. Kalinowsky, P. Mahlberg, H. Eberhardt, J. Hannappel, Goertz, Ch. Wendel, D. Werthmüller, U. Thoma, K. Fornet-Ponse, W. Meyer, M. Urban, V. Sokhoyan, K. Spieker, G. Reicherz, I. Keshelashvili, R. Ewald, A. Thiel, F. Afzal, D. Walther, and K.-T. Brinkmann

Subjects
Excitation function, Physics, Nuclear and High Energy Physics, Meson, 010308 nuclear & particles physics, media_common.quotation_subject, Nuclear Theory, FOS: Physical sciences, Observable, Polarization (waves), 01 natural sciences, Helicity, Asymmetry, Nuclear physics, Deuterium, 0103 physical sciences, ddc:530, High Energy Physics::Experiment, Neutron, Nuclear Experiment (nucl-ex), 010306 general physics, Nuclear Experiment, media_common
Abstract

Photoproduction of $\eta$ mesons from neutrons} \abstract{Results from measurements of the photoproduction of $\eta$ mesons from quasifree protons and neutrons are summarized. The experiments were performed with the CBELSA/TAPS detector at the electron accelerator ELSA in Bonn using the $\eta\to3\pi^{0}\to6\gamma$ decay. A liquid deuterium target was used for the measurement of total cross sections and angular distributions. The results confirm earlier measurements from Bonn and the MAMI facility in Mainz about the existence of a narrow structure in the excitation function of $\gamma n\rightarrow n\eta$. The current angular distributions show a forward-backward asymmetry, which was previously not seen, but was predicted by model calculations including an additional narrow $P_{11}$ state. Furthermore, data obtained with a longitudinally polarized, deuterated butanol target and a circularly polarized photon beam were analyzed to determine the double polarization observable $E$. Both data sets together were also used to extract the helicity dependent cross sections $\sigma_{1/2}$ and $\sigma_{3/2}$. The narrow structure in the excitation function of $\gamma n\rightarrow n\eta$ appears associated with the helicity-1/2 component of the reaction.

Published
2017
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24. Measurement of polarisation observables inKs0Σ+photoproduction off the proton

Author

Volker Metag, H. Dutz, S. Schadmand, T. Mertens, T. C. Jude, Matthew Lang, H. Schmieden, R. Ewald, D. E. Bayadilov, K. Fornet-Ponse, A. B. Gridnev, Mariana Nanova, D. Walther, A. Suele, V. Sokhoyan, Friedrich Klein, J. G. Messchendorp, V. Kleber, T. Szczepanek, M. Ostrick, Herbert Löhner, A. Roy, I. Jaegle, K.-T. Brinkmann, I. V. Lopatin, Ch. Schmidt, R. Varma, V. Crede, E. Gutz, D. Trnka, O. Jahn, R. Beck, Wolfgang Hillert, Lalit Mohan Pant, B. Bantes, S. Kammer, Ch. Funke, D. Elsner, Yu. A. Beloglazov, A. V. Sarantsev, V. A. Nikonov, R. W. Novotny, A. V. Anisovich, Ph. Hoffmeister, B. Schoch, D. Menze, Eberhard Klempt, J. Hannappel, Ch. Wendel, V. V. Sumachev, U. Thoma, J. Junkersfeld, S. Shende, H. Kalinowsky, D. V. Novinski, H. van Pee, B. Krusche, O. Bartholomy, Frank Klein, and Frank Frommberger

Subjects
Physics, Nuclear physics, Nuclear and High Energy Physics, Photon, Proton, Partial wave analysis, Hyperon, Bremsstrahlung, Photon energy, Nuclear Experiment, Nucleon, 7. Clean energy, Sigma baryon
Abstract

The reaction γ p → K S 0 Σ + is studied in the photon energy range from threshold. Linearly polarised photon beams from coherent bremsstrahlung enabled the first measurement of photon beam asymmetries in this reaction up to E γ = 1650 MeV . In addition, the recoil hyperon polarisation was determined through the asymmetry in the weak decay Σ + → p π 0 up to E γ = 2250 MeV . The data are compared to partial wave analyses, and the possible impact on the interpretation of a recently observed prominent structure in the cross section near the K ⁎ thresholds is discussed.

Published
2014

25. Experimental constraints on the ω–nucleus real potential

Author

D. Elsner, Frank Frommberger, Ph. Hoffmeister, Matthew Lang, V. Kleber, R. Schmitz, T. Seifen, Yu. A. Beloglazov, Wolfgang Hillert, Jens Hartmann, D. Piontek, I. V. Lopatin, T. Rostomyan, V. Metag, A. Wilson, B. Krusche, J. Hannappel, M. Gottschall, R. Ewald, K. Makonyi, H. Schmieden, D. E. Bayadilov, D. Kaiser, I. Jaegle, U. Wiedner, K.-T. Brinkmann, H. van Pee, A. Thiel, E. Gutz, Yasser Maghrbi, A. B. Gridnev, Mariana Nanova, D. Walther, U. Thoma, M. Grüner, Ch. Honisch, Ch. Hammann, Ch. Schmidt, J. Müller, K. Fornet-Ponse, Friedemann Zenke, V. Crede, S. Friedrich, P. Drexler, S. Kammer, A. Winnebeck, Steffen Schaepe, F. Dietz, H. Eberhardt, Ch. Wendel, Th. Challand, Ch. Funke, Janus Weil, I. Keshelashvili, D. Hammann, Satoru Hirenzaki, T. Odenthal, T. Dahlke, Hideko Nagahiro, Friedrich Klein, B. Bantes, S. Böse, H. Kalinowsky, and R. Beck

Subjects
Physics, education.field_of_study, Nuclear and High Energy Physics, Meson, Hadron, Population, Nuclear Theory, Carbon-12, Elementary particle, lcsh:QC1-999, Pion, Bound state, Atomic physics, Nucleon, education, Nuclear Experiment, lcsh:Physics
Abstract

In a search for $\omega$ mesic states, the production of $\omega$-mesons in coincidence with forward going protons has been studied in photon induced reactions on $^{12}$C for incident photon energies of 1250 - 3100 MeV. The $\pi^0 \gamma$ pairs from decays of bound or quasi-free $\omega$-mesons have been measured with the CBELSA/TAPS detector system in coincidence with protons registered in the MiniTAPS forward array. Structures in the total energy distribution of the $\pi^0 \gamma$ pairs, which would indicate the population and decay of bound $\omega~^{11}$B states, are not observed. The $\pi^0 \gamma$ cross section of 0.3 nb/MeV/sr observed in the bound state energy regime between -100 and 0 MeV may be accounted for by yield leaking into the bound state regime because of the large in-medium width of the $\omega$-meson. A comparison of the measured total energy distribution with calculations suggests the real part $V_0$ of the $\omega~^{11}$B potential to be small and only weakly attractive with $V_0(\rho=\rho_0) = -15\pm$ 35(stat) $\pm$20(syst) MeV in contrast to some theoretical predictions of attractive potentials with a depth of 100 - 150 MeV., Comment: 13 pages, 8 figures

Published
2014
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26. Determination of the eta '-nucleus optical potential

Author

Ch. Hammann, Friedemann Zenke, Ch. Honisch, Ch. Schmidt, R. Ewald, P. Drexler, A. Winnebeck, Yasser Maghrbi, E. Ya. Paryev, J. Müller, R. Beck, H. Eberhardt, Jens Hartmann, S. Friedrich, T. Seifen, I. Keshelashvili, Friedrich Klein, D. Walther, U. Thoma, A. Thiel, T. Dahlke, H. Schmieden, Matthew Lang, D. E. Bayadilov, A. B. Gridnev, Mariana Nanova, V. Metag, V. Kleber, Ch. Wendel, I. Jaegle, Eberhard Klempt, K.-T. Brinkmann, Wolfgang Hillert, D. Kaiser, J. Hannappel, Yu. A. Beloglazov, D. Piontek, D. Elsner, I. V. Lopatin, Ph. Hoffmeister, S. Böse, B. Krusche, H. Kalinowsky, S. Kammer, F. Dietz, Th. Challand, Ch. Funke, U. Wiedner, K. Fornet-Ponse, T. Odenthal, D. Hammann, K. Makonyi, H. van Pee, Steffen Schaepe, A. Wilson, Frank Frommberger, M. Grüner, V. Crede, M. Gottschall, E. Gutz, B. Bantes, and R. Schmitz

Subjects
Physics, Excitation function, Nuclear and High Energy Physics, Photon, Meson, 010308 nuclear & particles physics, Hadron, Nuclear Theory, Elementary particle, Electron, Nuclear matter, 01 natural sciences, 0103 physical sciences, Bound state, High Energy Physics::Experiment, Atomic physics, 010306 general physics, Nuclear Experiment
Abstract

The excitation function and momentum distribution of $\eta^\prime$ mesons have been measured in photon induced reactions on $^{12}{}$C in the energy range of 1250-2600 MeV. The experiment was performed with tagged photon beams from the ELSA electron accelerator using the Crystal Barrel and TAPS detectors. The data are compared to model calculations to extract information on the sign and magnitude of the real part of the $\eta^\prime$-nucleus potential. Within the model, the comparison indicates an attractive potential of -($37 \pm 10(stat)\pm10(syst)$) MeV depth at normal nuclear matter density. Since the modulus of this depth is larger than the modulus of the imaginary part of the $\eta^\prime$-nucleus potential of -($10\pm2.5$) MeV, determined by transparency ratio measurements, a search for resolved $\eta^\prime$-bound states appears promising., Comment: 13 pages, 6 figures

Published
2013

27. The impact of new polarization data from Bonn, Mainz and Jefferson Laboratory on $\gamma p \rightarrow \pi N$ multipoles

Author

Eberhard Klempt, A. V. Anisovich, V. L. Kashevarov, Y. Wunderlich, Jens Hartmann, A. V. Sarantsev, U. Thoma, I. I. Strakovsky, M. Ostrick, L. Tiator, Ulf-G. Meißner, R. Beck, Ron L. Workman, V. A. Nikonov, A. Thiel, M. Gottschall, D. Rönchen, and Michael Döring

Subjects
Physics, Scattering cross-section, Nuclear and High Energy Physics, Particle physics, 010308 nuclear & particles physics, media_common.quotation_subject, Hadron, Polarization (waves), 01 natural sciences, Asymmetry, Nuclear physics, 0103 physical sciences, Nuclear Experiment, 010306 general physics, Multipole expansion, Nuclear theory, media_common
Abstract

New data on pion-photoproduction off the proton have been included in the partial-wave analyses Bonn-Gatchina and SAID and in the dynamical coupled-channel approach Julich-Bonn. All reproduce the recent new data well: the double-polarization data for E, G, H, P and T in $\gamma p\rightarrow \pi^{0}p$ from ELSA, the beam asymmetry $ \Sigma$ for $\gamma p\rightarrow \pi^{0}p$ and $ \pi^{+}n$ from Jefferson Laboratory, and the precise new differential cross section and beam asymmetry data $\Sigma$ for $\gamma p\rightarrow \pi^{0}p$ from MAMI. The new fit results for the multipoles are compared with predictions not taking into account the new data. The mutual agreement is improved considerably but still far from being perfect.

Published
2016

28. Momentum dependence of the imaginary part of the $\omega$- and $\eta^\prime$-nucleus optical potential

Author

K. Makonyi, J. Hannappel, Ch. Funke, B. Krusche, H. van Pee, Ulrich Wiedner, Volker Metag, H. Eberhardt, T. Seifen, R. Schmitz, F. Kalischewski, Matthew Lang, T. Triffterer, Y. Wunderlich, E. Gutz, I. Keshelashvili, V. Crede, C. Sowa, Lilian Witthauer, D. Schaab, K. Koop, Friedrich Klein, Suvadeep Bose, F. Afzal, Reinhard Beck, D. Elsner, Ph. Hoffmeister, H. Schmieden, D. E. Bayadilov, D. Kaiser, M. Urban, Mariana Nanova, Ch. Wendel, Wolfgang Hillert, Frank Frommberger, M. Gottschall, V. Sokhoyan, U. Thoma, D. Werthmüller, M. Grüner, B. Bantes, Alastair J. Wilson, T. C. Jude, Jens Hartmann, Matthew L. Becker, D. Piontek, H. G. Zaunick, K. Spieker, D. Walther, J. Müller, A. Thiel, Ch. Hammann, P. Drexler, J. Müllers, Ch. Honisch, Ch. Schmidt, S. Friedrich, Francesco Messi, K.-T. Brinkmann, and T. Rostomyan

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Photon, Meson, 010308 nuclear & particles physics, High Energy Physics::Phenomenology, Nuclear Theory, 01 natural sciences, Omega, Momentum, 0103 physical sciences, Bound state, Production (computer science), ddc:530, High Energy Physics::Experiment, Absorption (logic), 010306 general physics, Nuclear Experiment, Glauber
Abstract

The photoproduction of $\omega$ and $\eta^\prime$ mesons off carbon and niobium nuclei has been measured as a function of the meson momentum for incident photon energies of 1.2-2.9 GeV at the electron accelerator ELSA. The mesons have been identified via the $\omega \rightarrow \pi^0 \gamma \rightarrow 3 \gamma$ and $\eta^\prime\rightarrow \pi^0 \pi^0\eta \rightarrow 6 \gamma$ decays, respectively, registered with the CBELSA/TAPS detector system. From the measured meson momentum distributions the momentum dependence of the transparency ratio has been determined for both mesons. Within a Glauber analysis the in-medium $\omega$ and $\eta^\prime$ widths and the corresponding absorption cross sections have been deduced as a function of the meson momentum. The results are compared to recent theoretical predictions for the in-medium $\omega$ width and $\eta^\prime$-N absorption cross sections. The energy dependence of the imaginary part of the $\omega$- and $\eta^\prime$-nucleus optical potential has been extracted. The finer binning of the present data compared to the existing data allows a more reliable extrapolation towards the production threshold. The modulus of the imaginary part of the $\eta^\prime$ nucleus potential is found to be about three times smaller than recently determined values of the real part of the $\eta^\prime$-nucleus potential, which makes the $\eta^\prime$ meson a suitable candidate for the search for meson-nucleus bound states. For the $\omega$ meson, the modulus of the imaginary part near threshold is comparable to the modulus of the real part of the potential. As a consequence, only broad structures can be expected which makes the observation of $\omega$ mesic states very difficult experimentally., Comment: 10 pages, 8 figures

Published
2016

29. Double-polarization observable G in neutral-pion photoproduction off the proton

Author

U. Thoma, V. Crede, F. Afzal, Reinhard Beck, D. Elsner, P. Klassen, H. Dutz, K.-T. Brinkmann, S. Kammer, S. Runkel, H. Eberhardt, D. Walther, I. Keshelashvili, Ch. Honisch, Ch. Hammann, K. Fornet-Ponse, Ch. Schmidt, Ch. Funke, B. Krusche, Ch. Wendel, M. Grüner, E. Gutz, Jens Hartmann, S. Böse, A. Winnebeck, G. Reicherz, A. V. Anisovich, P. Mahlberg, H. Kalinowsky, K. Spieker, M. Bichow, Friedrich Klein, S. Friedrich, J. Müllers, Eberhard Klempt, Volker Metag, A. V. Sarantsev, Matthew Lang, W. Meyer, St. Goertz, M. Urban, Frank Frommberger, D. Kaiser, M. Dieterle, V. A. Nikonov, F. Kalischewski, B. Bantes, V. Sokhoyan, K. Koop, R. Ewald, H. Schmieden, D. E. Bayadilov, A. Thiel, A. B. Gridnev, Mariana Nanova, M. Kube, M. Gottschall, Wolfgang Hillert, J. Hannappel, Ph. Hoffmeister, V. Kleber, T. Seifen, Alastair J. Wilson, T. C. Jude, D. Piontek, I. V. Lopatin, Lilian Witthauer, D. Hammann, K. Makonyi, S. Reeve, H. van Pee, and J. Müller

Subjects
Physics, Nuclear and High Energy Physics, Photon, Proton, 010308 nuclear & particles physics, Nuclear Theory, Bremsstrahlung, Diamond, FOS: Physical sciences, Observable, Photon energy, engineering.material, Polarization (waves), 01 natural sciences, Nuclear physics, Pion, 0103 physical sciences, engineering, ddc:530, Nuclear Experiment (nucl-ex), 010306 general physics, Nuclear Experiment
Abstract

This paper reports on a measurement of the double-polarization observable G in $\pi^0$ photoproduction off the proton using the CBELSA/TAPS experiment at the ELSA accelerator in Bonn. The observable G is determined from reactions of linearly-polarized photons with longitudinally-polarized protons. The polarized photons are produced by bremsstrahlung off a properly oriented diamond radiator. A frozen spin butanol target provides the polarized protons. The data cover the photon energy range from 617 to 1325 MeV and a wide angular range. The experimental results for G are compared to predictions by the Bonn-Gatchina (BnGa), J\"ulich-Bonn (J\"uBo), MAID and SAID partial wave analyses. Implications of the new data for the pion photoproduction multipoles are discussed.

Published
2016
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30. Determination of the real part of the η ′ -Nb optical potential

Author

J. Müllers, Y. Wunderlich, Matthew Lang, J. Hannappel, Alastair J. Wilson, T. C. Jude, M. Becker, Ulrich Wiedner, U. Thoma, R. Schmitz, T. Triffterer, E. Gutz, D. Elsner, V. Crede, V. Metag, Ph. Hoffmeister, Suvadeep Bose, Christian Schmidt, A. Thiel, K. Spieker, B. Krusche, Friedrich Klein, Ch. Hammann, T. Rostomyan, K.-T. Brinkmann, Wolfgang Hillert, D. Walther, K. Koop, M. Urban, D. Schaab, E. Ya. Paryev, D. Piontek, Jörg H. Müller, Jens Hartmann, F. Afzal, H. Schmieden, D. E. Bayadilov, Mariana Nanova, K. Makonyi, H. van Pee, Hans-Georg Zaunick, S. Friedrich, Lilian Witthauer, Francesco Messi, Ch. Honisch, F. Kalischewski, Reinhard Beck, Frank Frommberger, Ch. Wendel, C. Sowa, D. Werthmüller, M. Grüner, I. Keshelashvili, and T. Seifen

Subjects
Excitation function, Physics, Meson, 010308 nuclear & particles physics, Nuclear Theory, Bremsstrahlung, Particle accelerator, Nuclear matter, 01 natural sciences, law.invention, Nuclear physics, Momentum, law, Excited state, 0103 physical sciences, Bound state, High Energy Physics::Experiment, ddc:530, Atomic physics, 010306 general physics, Nuclear Experiment
Abstract

The excitation function and momentum distribution of {\eta}' mesons have been measured in photoproduction off 93^Nb in the energy range of 1.2-2.9 GeV. The experiment has been performed with the combined Crystal Barrel and MiniTAPS detector system, using tagged photon beams from the ELSA electron accelerator. Information on the sign and magnitude of the real part of the {\eta}'-Nb potential has been extracted from a comparison of the data with model calculations. An attractive potential of -(41 \pm 10(stat) \pm 15(syst)) MeV depth at normal nuclear matter density is deduced within model uncertainties. This value is consistent with the potential depth of -(37 \pm 10(stat) \pm 10(syst)) MeV obtained in an earlier measurement for a light nucleus (carbon). This relatively shallow {\eta}'-nucleus potential will make the search for {\eta}'-nucleus bound states more difficult., Comment: 9 pages, 6 figures

Published
2016

31. Evidence for a negative-parity spin-doublet of nucleon resonances at 1.88 GeV

Author

Eberhard Klempt, H. Schmieden, A. V. Sarantsev, V. A. Nikonov, A. V. Anisovich, and U. Thoma

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Chiral symmetry, Degenerate energy levels, FOS: Physical sciences, Parity (physics), High Energy Physics - Experiment, Nuclear physics, High Energy Physics - Experiment (hep-ex), Pion, Nuclear Experiment (nucl-ex), Nuclear Experiment, Nucleon, Excitation
Abstract

Evidence is reported for two nucleon resonances with spin-parity $J^P=1/2^-$ and $J^P=3/2^-$ at a mass just below 1.9\,GeV. The evidence is derived from a coupled-channel analysis of a large number of pion and photo-produced reactions. The two resonances are nearly degenerate in mass with two resonances of the same spin but positive parity. Such parity doublets are predicted in models claiming restoration of chiral symmetry in high-mass excitations of the nucleon. Further examples of spin parity doublets are found in addition. Alternatively, the spin doublet can be interpreted as member of the 56-plet expected in the third excitation band of the nucleon. Implications for the problem of the {\it missing resonances} are discussed., 10 pages, 3 figures, 4 tables, minor revision

Published
2012

32. Transparency ratio in γA→η′A′ and the in-medium η′ width

Author

B. Krusche, I. Horn, V. Metag, A. Radkov, S. Lugert, O. Bartholomy, D. Menze, Angels Ramos, Eberhard Klempt, S. Höffgen, K.-T. Brinkmann, T. Szczepanek, Ch. Wendel, I. Jaegle, A. Süle, V. V. Sumachev, J. Junkersfeld, K. Essig, C. Morales, M. Fuchs, H. Dutz, Frank Klein, Yu. A. Beloglazov, A. Ehmanns, E. Gutz, Ch. Funke, M. Konrad, Lalit Mohan Pant, M. Ostrick, H. Kalinowsky, M. Pfeiffer, Friedrich Klein, K. Makonyi, R. Ewald, I. V. Lopatin, T. Mertens, Herbert Löhner, H. van Pee, V. Crede, B. Kopf, D. Trnka, J. Langheinrich, J. G. Messchendorp, D. Elsner, U. Thoma, Ankhi Roy, R. W. Novotny, J. Lotz, D. Walther, Ph. Hoffmeister, B. Schoch, Ch. Schmidt, Eulogi Oset, H. Schmieden, D. E. Bayadilov, A. B. Gridnev, Mariana Nanova, I. Fabry, S. Schadmand, R. Gregor, and R. Varma

Subjects
Physics, Nuclear and High Energy Physics, Photon, Proton, Meson, 010308 nuclear & particles physics, Scattering, Nuclear Theory, Niobium, chemistry.chemical_element, Rest frame, 7. Clean energy, 01 natural sciences, Momentum, Nuclear physics, Cross section (physics), chemistry, 0103 physical sciences, High Energy Physics::Experiment, Atomic physics, Nuclear Experiment, 010306 general physics
Abstract

The photoproduction of η ′ -mesons off different nuclei has been measured with the CBELSA/TAPS detector system for incident photon energies between 1500–2200 MeV. The transparency ratio has been deduced and compared to theoretical calculations describing the propagation of η ′ -mesons in nuclei. The comparison indicates a width of the η ′ -meson of the order of Γ = 15 – 25 MeV at ρ = ρ 0 for an average momentum p η ′ = 1050 MeV / c , at which the η ′ -meson is produced in the nuclear rest frame. The inelastic η ′ N cross section is estimated to be 3–10 mb. Parameterizing the photoproduction cross section of η ′ -mesons by σ ( A ) = σ 0 A α , a value of α = 0.84 ± 0.03 has been deduced.

Published
2012

33. A Large GEM-TPC Prototype Detector for anda

Author

F. Cusanno, R. Arora, J. Kunkel, M. Kiš, P. Müllner, Kunio Suzuki, J. Hehner, R. Schmitz, Y. Leifels, D. Soyk, D. Walther, I. Konorov, J. Voss, R. H. Munzer, Christian Schmidt, C. Hs, N. Herrmann, Johann Zmeskal, V. Kleipa, S. Dørheim, S. Neubert, S. Schwab, Harvey A. Risch, N. Kurz, M. Vandenbroucke, H. Angerer, U. Thoma, R. Beck, Klaus Peters, Laura Fabbietti, M. Ball, Sebastian Uhl, J. Frühauf, Matthew Lang, F.V. Böhmer, Bernd Voss, Soumen Paul, Alexander Winnebeck, J.-C. Chen, J. Fröppner, M. Berger, D. Kaiser, J. Weinert, and B. Ketzer

Subjects
Physics, Luminosity (scattering theory), Time projection chamber, GEM, Spectrometer, Physics::Instrumentation and Detectors, PANDA, Detector, Physics and Astronomy(all), Micro-pattern gas detectors, Particle Tracking, Nuclear physics, Phase space, Gas electron multiplier, Physics::Accelerator Physics, TPC, Nuclear Experiment, Beam (structure), Storage ring, FAIR
Abstract

The PANDA spectrometer will be a state of the art universal detector for strong interaction studies at the High-Energy Storage Ring (HESR) in the future international Facility for Anti-proton and Ion Research (FAIR) at GSI, Darmstadt. The detector is designed to take advantage of the extraordinary physics potential which will be available utilizing high intensity, phase space cooled anti-proton beams. This facility will provide a cooled anti-proton beam−2with momenta of 1.5-15 GeV/c, a maximal luminosity of 2×1032cms−1 that translates into 2×107 pp annihilations per second. A GEM based Time Projection Chamber (TPC) was one of the central tracker candidates for the PANDA experiment. To check the feasibility of such a detector system, a large prototype GEM-TPC was built and tested inside the FOPI Spectrometer at GSI. A set of three Gas Electron Multiplier (GEM) foils were used as amplification stage instead of Multi Wire Proportional Chambers. In this report, the design, construction, characterization of the prototype-detector system will be discussed in detail along with the results of recent beam tests.

Published
2012
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34. Photoproduction of meson pairs: First measurement of the polarization observable Is

Author

Matthew Lang, T. Mertens, Herbert Löhner, A. Suele, Michael Fuchs, V. Crede, D. Piontek, D. Walther, M. Pfeiffer, I. V. Lopatin, A. Thiel, V. Metag, Ch. Schmidt, H. Dutz, V. Sokhoyan, J. G. Messchendorp, M. Kotulla, J. C. S. Bacelar, Friedrich Klein, R. Beck, I. Jaegle, Winston Roberts, M. Ostrick, R. Gregor, R. Ewald, R. Castelijns, S. Schadmand, Ch. Weinheimer, H. Schmieden, R. Varma, D. E. Bayadilov, A. B. Gridnev, Mariana Nanova, D. Trnka, D. Elsner, T. Szczepanek, V. Kleber, R. W. Novotny, Ph. Hoffmeister, S. Kammer, B. Schoch, Ch. Funke, Lalit Mohan Pant, S. Lugert, Wolfgang Hillert, Eberhard Klempt, Ankhi Roy, V. A. Nikonov, D. Menze, I. Horn, A. V. Anisovich, Ch. Wendel, B. Bantes, V. V. Sumachev, Yu. A. Beloglazov, A. V. Sarantsev, H. Kalinowsky, B. Krusche, E. Gutz, D. V. Novinski, S. Shende, U. Thoma, H. van Pee, O. Bartholomy, J. Junkersfeld, Frank Frommberger, and Frank Klein

Subjects
Physics, Nuclear and High Energy Physics, Photon, Meson, Proton, Linear polarization, media_common.quotation_subject, Partial wave analysis, FOS: Physical sciences, Observable, Polarization (waves), Asymmetry, Nuclear physics, High Energy Physics::Experiment, Nuclear Experiment (nucl-ex), Nuclear Experiment, media_common
Abstract

The polarization observable I^s, a feature exclusive to the acoplanar kinematics of multi-meson final states produced via linearly polarized photons, has been measured for the first time. Results for the reaction g p -> p pi0 eta are presented for incoming photon energies between 970 MeV and 1650 MeV along with the beam asymmetry I^c. The comparably large asymmetries demonstrate a high sensitivity of I^s to the dynamics of the reaction. Fits using Bonn-Gatchina partial wave analysis demonstrate that the new polarization observables carry significant information on the contributing partial waves., 11 pages, 6 figures, v2 to appear in Phys. Lett. B

Published
2010

35. Photoproduction of multi-meson final states −- recent results from the Crystal-Barrel/TAPS experiment at ELSA

Author

Belsa and U. Thoma

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Meson, media_common.quotation_subject, Partial wave analysis, Astronomy and Astrophysics, Observable, Asymmetry, Crystal, Nuclear physics, Baryon, Phase space, Nuclear Experiment, Instrumentation, Beam (structure), media_common
Abstract

Multi-meson final states such as γp → pπ0π0 and γp → p π0η have been investigated with the Crystal-Barrel/TAPS experiment at ELSA. Baryon cascades via Δπ and Δη and also via higher mass baryon resonances are clearly observed. Based on this data and on data from other reactions a partial wave analysis has been performed from which partial decay widths of various N* and Δ* states into the different pπ0π0 and pπ0η decay channels have been determined, leading partly to unexpected results. In addition, polarisation observables have been investigated. The beam asymmetry ∑ has been determined for both reactions and double polarisation data using a longitudinally polarised target and a circularly or linearly polarised photon beam has been taken. Given the angular coverage of the Crystal-Barrel/TAPS experiment this data covers almost the full angular range and phase space. This data will provide new and important information for the partial wave analyses and bring us one step closer towards a complete experiment.

Published
2009

36. Photoproduction of $ \eta$ -mesons off neutrons from a deuteron target

Author

B. Krusche, A. V. Sarantsev, V. A. Nikonov, Eberhard Klempt, A. V. Anisovich, U. Thoma, and I. Jaegle

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Meson, Partial wave analysis, Nuclear Theory, Helicity, High Energy Physics - Phenomenology, Formalism (philosophy of mathematics), Amplitude, Deuterium, High Energy Physics::Experiment, Neutron, Nuclear Experiment
Abstract

A formalism is developed for the partial wave analysis of data on meson photoproduction off deuterons and applied to photoproduction of $\eta$ and $\pi^0$ mesons. Different interpretations of a dip-bump structure of the $\eta$ photoproduction cross section in the 1670 MeV region are presented and discussed. Helicity amplitudes for two low-mass $S_{11}$ states are determined., Comment: 11 pages, 13 figures

Published
2009

37. Data on Is and Ic in γ→p→pπ0π0 reveal cascade decays of N(1900) via N(1520)π

Author

V. Sokhoyan, E. Gutz, H. van Pee, A.V. Anisovich, J.C.S. Bacelar, B. Bantes, O. Bartholomy, D. Bayadilov, R. Beck, Y. Beloglazov, R. Castelijns, V. Crede, H. Dutz, D. Elsner, R. Ewald, F. Frommberger, M. Fuchs, Ch. Funke, R. Gregor, A. Gridnev, W. Hillert, Ph. Hoffmeister, I. Horn, I. Jaegle, J. Junkersfeld, H. Kalinowsky, S. Kammer, V. Kleber, Frank Klein, Friedrich Klein, E. Klempt, M. Kotulla, B. Krusche, M. Lang, H. Löhner, I. Lopatin, S. Lugert, T. Mertens, J.G. Messchendorp, V. Metag, M. Nanova, V.A. Nikonov, D. Novinski, R. Novotny, M. Ostrick, L. Pant, M. Pfeiffer, D. Piontek, A. Roy, A.V. Sarantsev, Ch. Schmidt, H. Schmieden, S. Shende, A. Süle, V.V. Sumachev, T. Szczepanek, A. Thiel, U. Thoma, D. Trnka, R. Varma, D. Walther, Ch. Wendel, and A. Wilson

Subjects
Polarization observables, Nuclear Theory, Baryon spectroscopy, Double meson photoproduction, High Energy Physics::Experiment, Nuclear Experiment, lcsh:Physics, lcsh:QC1-999
Abstract

Photoproduction of two neutral pions off the proton is studied using linearly polarized photons, and the polarization observables Is and Ic are measured for the first time. These two observables are unique to multi-meson final states; they characterize correlations between the linear photon polarization and the direction of outgoing single particles in photoproduction of three-body final states. The Is and Ic distributions suggest that, in the 1.8 to 2.0 GeV mass region, the N(1520)3/2−π intermediate state is reached with reaction dynamics consistent with a dominant JP=3/2+ wave. These data are included in the Bonn–Gatchina (BnGa) partial wave analysis which is based on a large variety of data; the analysis confirms a significant contribution from the reaction chain γp→N(1900)3/2+→N(1520)3/2−π0→pπ0π0. Keywords: Baryon spectroscopy, Double meson photoproduction, Polarization observables

Published
2015

38. Interference phenomena in the JP = 1/2− wave in η photoproduction

Author

B. Krusche, Eberhard Klempt, A. V. Sarantsev, V. A. Nikonov, A. V. Anisovich, U. Thoma, and D. Werthmüller

Subjects
Excitation function, Physics, Nuclear and High Energy Physics, Meson, Partial wave analysis, Nuclear Theory, Resonance, Scattering amplitude, Nuclear physics, Neutron, Atomic physics, Nuclear Experiment, Nucleon, Crystal Ball
Abstract

The recent precise experimental results for the photoproduction of η-mesons off the neutron measured with the Crystal Ball/TAPS calorimeter at the MAMI accelerator have been investigated in detail in the framework of the Bonn-Gatchina coupled-channel model. The main result is that the narrow structure observed in the excitation function of γη → nη can be reproduced fully with a particular interference pattern in the J P = 1/2− partial wave. Introduction of the narrow resonance N(1685) with the properties reported in earlier publications deteriorates the quality of the fit.

Published
2015

39. Three-Body Nature ofN*andΔ*Resonances from Sequential Decay Chains

Author

Frank Klein, V. Sokhoyan, A. Wilson, E. Gutz, M. Pfeiffer, S. Shende, J. Junkersfeld, J. G. Messchendorp, R. Beck, D. V. Novinski, Ch. Schmidt, M. Kotulla, D. Walther, V. A. Nikonov, R. Castelijns, Matthew Lang, Wolfgang Hillert, A. Thiel, A. V. Anisovich, I. Horn, S. Lugert, H. Kalinowsky, Cbelsa, U. Thoma, Eberhard Klempt, B. Bantes, V. Kleber, D. Elsner, Volker Metag, H. van Pee, R. Gregor, R. Varma, T. Mertens, Friedrich Klein, Herbert Löhner, R. W. Novotny, Yu. A. Beloglazov, B. Krusche, A. Roy, A. V. Sarantsev, Ph. Hoffmeister, O. Bartholomy, L. M. Pant, H. Dutz, S. Kammer, Bernard Metsch, Frank Frommberger, D. Piontek, Ch. Wendel, Ch. Funke, I. V. Lopatin, V. V. Sumachev, H. Schmieden, V. Crede, D. E. Bayadilov, A. B. Gridnev, Mariana Nanova, A. Süle, I. Jaegle, M. Ostrick, D. Trnka, J. C. S. Bacelar, R. Ewald, T. Szczepanek, and M. Fuchs

Subjects
Physics, Partial wave analysis, Nuclear Theory, General Physics and Astronomy, Dalitz plot, Delta baryon, Particle decay, Pion, Isobar, High Energy Physics::Experiment, Decay chain, Atomic physics, Nuclear Experiment, Nucleon
Abstract

The N pi(0)pi(0) decays of positive-parity N* and Delta* resonances at about 2 GeV are studied at ELSA by photoproduction of two neutral pions off protons. The data reveal clear evidence for several intermediate resonances: Delta(1232), N(1520)3/2(-), and N(1680)5/2(+), with spin parities J(P) = 3/2(+), 3/2(-), and 5/2(+). The partial wave analysis (within the Bonn-Gatchina approach) identifies N(1440)1/2(+) and the N(pi pi)s (wave) (abbreviated as N sigma here) as further isobars and assigns the final states to the formation of nucleon and Delta resonances and to nonresonant contributions. We observe the know Delta(1232)pi decays of Delta(1910)1/2(+), Delta(1920)3/2(+), Delta(1905)5/2(+), Delta(1950)7/2(+), and of the corresponding spin-parity series in the nucleon sector, N(1880)1/2(+), N(1900)3/2(+), N(2000)5/2(+), and N(1990)7/2(+). For the nucleon resonances, these decay modes are reported here for the first time. Further new decay modes proceed via N(1440)1/2(pi)(+), N(1520)3/2(pi)(-) , N(1680)5/2(pi)(+), and N sigma. The latter decay modes are observed in the decay of N* resonances and at most weakly in Delta(*) decays. It is argued that these decay modes provide evidence for a 3-quark nature of N* resonances rather than a quark-diquark structure.

Published
2015

40. Photoproduction of omega mesons off protons and neutrons

Author

A. Süle, S. Höffgren, O. Bartholomy, M. Kotulla, Ankhi Roy, M. Konrad, Friedrich Klein, M. Ostrick, S. Schadmand, Matthew Lang, H. Dutz, M. Pfeiffer, J. C. S. Bacelar, V. Kleber, S. Shende, J. Junkersfeld, H. Schmieden, D. E. Bayadilov, V. Crede, H. Kalinowsky, R. Ewald, A. B. Gridnev, Mariana Nanova, I. Jaegle, A. V. Anisovich, Ch. Schmidt, T. Szczepanek, D. Menze, H. van Pee, S. Kammer, Frank Klein, R. Varma, F. Dietz, A. Wilson, I. V. Lopatin, T. Mertens, Herbert Löhner, U. Thoma, V. Shklyar, Ch. Wendel, Lalit Mohan Pant, Frank Frommberger, C. Funke, R. Beck, D. Walter, V. V. Sumachev, J. G. Messchendorp, R. W. Gothe, R. Castelijns, R. Gregor, D. Trnka, E. Gutz, V. Metag, B. Bantes, T. Rostomyan, V. A. Nikonov, I. Horn, S. Lugert, Eberhard Klempt, Y. A. Belogazov, D. Elsner, R. W. Novotny, Ph. Hoffmeister, B. Schoch, Wolfgang Hillert, B. Krusche, D. V. Novinski, and Research unit Nuclear & Hadron Physics

Subjects
Nuclear reaction, Physics, TAPS, Nuclear and High Energy Physics, Proton, Meson, Astrophysics::High Energy Astrophysical Phenomena, Hadron, Nuclear Theory, WIDTH, Photon energy, DEUTERON, Nuclear physics, Deuterium, NUCLEAR MEDIUM, Neutron, High Energy Physics::Experiment, PHI-PHOTOPRODUCTION, SPECTROMETER, Atomic physics, Nucleon, Nuclear Experiment, MATTER
Abstract

Omega photoproduction off hydrogen and deuterium has been studied with the tagged photon beam of the ELSA accelerator in Bonn for photon energies up to 2.0 GeV. The omega meson has been identified via the omega -> pi(0) gamma -> gamma gamma gamma decay mode, using the combined setup of the Crystal Barrel/TAPS detector systems. Both inclusive and exclusive analyses have been carried out. Differential and total cross-sections have been derived for omega mesons produced off free protons and off protons and neutrons bound in deuterium. The cross-section for the production off the bound neutron is found to be a factor of a parts per thousand 1.3 larger than the one off the bound proton in the incident beam energy region 1.2 GeV

Published
2015

41. Experimental access to Transition Distribution Amplitudes with the P̄ANDA experiment at FAIR

Author

M. C. Mora Espí, Pawel Marciniewski, K. Makonyi, Yupeng Yan, S. Wronka, D. Pietreanu, Shaji Kumar, N. Belikov, D. I. Glazier, A. Gillitzer, K. Khanchai, Ajay Kumar Rai, M. Steinen, D. Calvo, Yury Tikhonov, A. A. Derevschikov, T. A. Pocheptsov, R.A. Salmin, P. Balanutsa, B. J. Liu, P. N. Deepak, A. E. Blinov, S. Lange, S. Ryzhikov, G. Kalicy, Arpit Parmar, P. Musiol, G. D. Alexeev, D. P. Watts, Lennart Isaksson, Tobias Stockmanns, E. Gutz, P. F. Dalpiaz, Zhi Liu, D. Marchand, S. Grieser, A. Gerhardt, D. Kangh, L. Fava, A. A. Festchenko, Harphool Kumawat, I. Zimmermann, M. Albrecht, B. Krusche, A. Sanchez Lorente, E. A. Strokovsky, M. A. Pasyuk, J. Ritman, P. C. Vinodkumar, T. Quagli, M.G. Sapozhnikov, Ashok Kumar, Herbert Koch, V. I. Astakhov, V. Serdyuk, K. M. von Würtemberg, D. Münchow, Hans-Georg Zaunick, S. Marcello, M. Ullrich, A. Mustafa, Paola Gianotti, T. Kuske, Michaela Thiel, Kamal K. Seth, S. Schlimme, C. Schwarz, M. Savrie, B. Ketzer, Jerzy Smyrski, E. Etzelmüller, A. G. Fedunov, H. Sohlbach, K. Malgorzata, Victor Bobrovnikov, R.Sh. Teshev, L. Ayut, V.M. Abazov, B. Spruck, B. Kamys, D. Mülhheim, Krzysztof Swientek, S. Schadmand, M. V. Korzihik, Zbigniew Rudy, Matei Eugen Vasile, T. Wasem, J. Schwiening, D. Lehmann, M. Patsyuk, Karin Schönning, W. Czyzycki, M. Zühlsdorf, V. N. Goryachev, A. G. Zorin, A. Davidenko, W. Lauth, B. Fröhlich, A. Amoroso, V. Lucherini, P. Schakel, Grzegorz Korcyl, G.A. Mustafaev, Smbat Grigoryan, Ajit Kumar Mohanty, Grzegorz Filo, R. Veenstra, P. Wüstner, J. Marton, Boris Batyunya, L. Ferrero, A. N. Skachkova, Edward Lisowski, I. Garzia, D. Bremer, T. Eissner, D. Lin, Y.M. Goncharenko, Soumen Paul, A.A. Efremov, Dipanwita Dutta, Alberto Rotondi, M. Michel, B. Slowinski, A. Arefiev, Philip Woods, I. Augustin, Yan Liang, A. Karavdina, M. Greco, P. Rosier, Antoni Szczurek, N. Saito, K. Föhl, T. Schröder, B. Singh, Mariana Nanova, Andreas Herten, Oleg V. Missevitch, S.A. Zaporozhets, K.-T. Brinkmann, Sukanta Dash, A. Filippi, A. Trzcinski, Marek Idzik, M. O. Distler, J. Schumann, C. Sowa, I. Konorov, J. C. van der Weele, Mathias Fink, A. E. Yakutin, B. Kopf, E. Atomssa, A. Pitka, R. Karabowicz, H. H. Leithoff, Angelo Rivetti, S. Pornrad, S. Diehl, M. Maggiora, B. Kröck, R. Duchat, O. Levitskaya, Gianluigi Boca, Krzysztof Korcyl, Gianangelo Bracco, Harald Kleines, F. Nerling, L. Caldeira Balkeståhl, S. Coli, E. Perevalova, T. Gessler, Klaus Peters, A. Magiera, Vassili Kachanov, M. Hawryluk, S. Ong, R. Varma, X. Shen, T. Czyzewski, M. Domagala, S. Godre, M. Zyzak, J. Pettersson, F. Uhlig, F. De Mori, P.J.J. Lemmens, Alexander D. Vasiliev, Mohammed Al-Turany, Q. Hu, Andrzej Kupsc, R. Schmitz, P. Mahlberg, P. De Remigis, C. Schnier, S. Lusso, R. Dosdall, L. Zotti, J. Van de Wiele, A. Britting, S. Fissum, Zhigang Li, Jozef Zlomanczuk, Amiran Tomaradze, S. Spataro, U. Müller, R. Valente, V. Uzhinsky, Giulio Stancari, G. S. Shabratova, I. Keshelashvili, S. Jowzaee, Harald Merkel, C. Guaraldo, S. Li, Christian Schmidt, M. Steinacher, V. Kozlov, Yu.N. Rogov, A. Bianconi, T. Held, V. Datar, Andrei Fedorov, H. Orth, T. Weber, A. Kozela, Piotr Salabura, M. Destefanis, Andrea Lavagno, M. Kuhlmann, B. Ma, J. Pychy, Piotr Lebiedowicz, L. Capozza, Dominik Kwiatkowski, Andrew Levin, A. Wilms, Germán Mazza, Matthias Richter, Wojciech Krzemien, Sean A Dobbs, J. Pochodzalla, I. Shein, H. Ohm, Paolo Montagna, Paul Alois Buhler, Y. Naryshkin, Hans Calén, A. Apostolou, S. Orfanitski, V. Grishin, A. Kashchuk, V. Kormilitsin, Tomasz Fiutowski, M. Mingnore, M. Krebs, A. Dolgolenko, E. Fioravanti, P.-E. Tegnér, A. Chlopik, A. Gromliuk, Andreas Lehrach, I. Georgadze, B. Czech, B. Zwieglinski, Kurt Hansen, W. Schäfer, C. Motzko, R. Kunne, P. Genova, J. Lühning, A. Psyzniak, S. Bianco, H. Smit, Nicola Bianchi, Felice Iazzi, J. Rieke, M. Fritsch, R. Dzhygadlo, O. Corell, E. Pace, S. I. Manaenkov, V. Chandratre, S. Sosio, A. Olshevskiy, T. Johansson, S. Sanchez, Concettina Sfienti, R. F. Parodi, D. Walther, T. Saito, E. Köhler, Zhi Sun, Markus Büscher, P. Kulessa, Magnus Wolke, I. Kisel, V. Tokmenin, Alexander Vodopyanov, J.H. Zhao, C. Wang, M. Kube, M. Kavatsyuk, T. Hennino, Johann Zmeskal, V. Varentsov, C. Morales Morales, S. Esch, R. Kliemt, G. Schepers, S. Poslavskiy, Alessandro Drago, Dan Pantea, M. Imre, W. Eyrich, D. Melnychuk, M.P. Bussa, Dirk Grunwald, I. Lehmann, D. Rodríguez Piñeiro, Kjell Fransson, A. P. Onuchin, Valery Dormenev, M. Rossbach, F. E. Maas, Giuseppe Giraudo, M. Pelizäus, D. P. Mohanta, H. Deppe, C. Rosenbaum, M. Cardinali, A. G. Denig, A. Boukharov, V. Abramov, A. Hayrapetyan, K. Pysz, Vladimir Blinov, A. K. Hergemöller, A. Ryazantsev, K. Kalita, P. Wintz, Raghunath Sahoo, V. Akishina, P. A. Semenov, V. Balanutsa, Mikael Lundin, M. M. Macri, Anne-Laure Martin, A. Karmokov, U. Cahit, A. Demekhin, G. Rosner, W. Erni, S. Plueger, S. Leiber, Michael Werner, L. Schmitt, S. Costanza, Bent Schröder, R. Arora, D. Deermann, M. Leyhe, S.A. Kononov, S. Belostotski, Ulrich Wiedner, Maria Krawczyk, L. V. Malinina, M. Tiemens, Yu.M. Mel'nik, Ch. Schmidt, O. Merle, U. Thoma, M. Babai, A. Semenov, R. Maier, Ankhi Roy, Michael Düren, L. V. Nogach, E. Widmann, A. Zhadanov, Valentino Rigato, Stanisław Kistryn, P. Fedorets, K. Suzuki, D. A. Morozov, Franco Bradamante, Torbjörn Bäck, L. Busso, C. Le Galliard, Bhavin Patel, Alessandro Bressan, K. Chinorat, M. Wojciechowski, A. Lehmann, A.F. Makarov, A. Galoyan, P. Wieczorek, T. Holtmann, Bernd Voss, Aleksandra Wrońska, J. S. Díaz, M. Hoek, D. Veretennikov, F. H. Heinsius, P. Brandys, F. Balestra, H. Flemming, F. Lisowski, H. Younis, Paweł Moskal, G. Maniscalco, P. Jasinski, V. K. Rodionov, J. G. Messchendorp, R. Schnell, O. Miklukho, D. Prasuhn, M. Zambrana, M. Kümmel, L. Cao, I. Marishev, A. Bersani, Bo Cederwall, K. Götzen, L. Lavezzi, S. Vejdani, N. G. Minaev, Herbert Löhner, V. Metag, R. W. Novotny, E. Tomasi-Gustafsson, N. B. Skachkov, A. Cebulla, Bartosz Mindur, V. Chernetsky, B. Seitz, Daniel M. Kaplan, E. K. Koshurnikov, B. Ramstein, A. Kulkarni, B. J. Roy, T. Sefzick, D. Khaneft, D. Branford, A. A. Piskun, Reinhard Beck, S. Bleser, Yu. Yu. Lobanov, R. Siudak, V. I. Lobanov, E. A. Kravchenko, S. Bukreeva, A. Samartsev, U. Thöring, F. Feldbauer, Ting Xiao, Patrick Achenbach, Hongwei Liu, Johannes Peter Wessels, D. Bettoni, Yu.I. Davydov, V. I. Dormenev, Genady Gavrilov, Ch. Wendel, M. Yu. Barabanov, Kirill M. Semenov-Tian-Shansky, R. Birsa, T. Bel, Günter Kemmerling, A. Khoukaz, V. Carassiti, B. Galnander, Jifeng Hu, M. Bragadireanu, I. A. Kuyanov, Bruce Yabsley, Andrey V. Izotov, O. Noll, J. Kunkel, A. Dbeyssi, K. Suvorov, Vivekanand Jha, Wolfgang Kuhn, Hasko Stenzel, O. Malyshev, A. A. Sokolov, U. Kurilla, G. Kuhl, D. Kaiser, P. Strzempek, A. Goerres, J. Biernat, D. G. Ireland, H. Xu, M. K. Suleimanov, G. Sterzenbach, E. Prencipe, A. Ortiz, N. I. Zhuravlev, A. Täschner, A. Gerasimov, T. Triffterer, M. Deiseroth, A. Wilson, Marek Palka, M. Lindemulder, A. Y. Barnyakov, V.Kh. Dodokhov, D. Nicmorus, Andrey Uzunian, A. Ehret, R. Nellen, Ch. Hammann, M. Steinke, V. L. Malyshev, P. Drexler, Richard Wheadon, A. Cotta Ramusino, P. Sarin, Riccardo Introzzi, H. Clement, I. Kulakov, M. Zuehlsdorf, M. Galuska, S. Kliczewski, G.B. Pontecorvo, D. Przyborowski, Mihai Caprini, V. V. Mochalov, M. Jadhav, M. Mikirtychyants, M. Traxler, Frank Goldenbaum, Research unit Nuclear & Hadron Physics, The PANDA Collaboration, Null, Singh, B. P, Erni, W., Keshelashvili, I., Krusche, B., Steinacher, M., Liu, B., Liu, H., Liu, Z., Shen, X., Wang, C., Zhao, J., Albrecht, M., Fink, M., Heinsius, F. H., Held, T., Holtmann, T., Koch, H., Kopf, B., Kümmel, M., Kuhl, G., Kuhlmann, M., Leyhe, M., Mikirtychyants, M., Musiol, P., Mustafa, A., Pelizäus, M., Pychy, J., Richter, M., Schnier, C., Schröder, T., Sowa, C., Steinke, M., Triffterer, T., Wiedner, U., Beck, R., Hammann, C., Kaiser, D., Ketzer, B., Kube, M., Mahlberg, P., Rossbach, M., Schmidt, C., Schmitz, R., Thoma, U., Walther, D., Wendel, C., Wilson, A., Bianconi, A., Bragadireanu, M., Caprini, M., Pantea, D., Pietreanu, D., Vasile, M. E., Patel, B., Kaplan, D., Brandys, P., Czyzewski, T., Czyzycki, W., Domagala, M., Hawryluk, M., Filo, G., Krawczyk, M., Kwiatkowski, D., Lisowski, E., Lisowski, F., Fiutowski, T., Idzik, M., Mindur, B., Przyborowski, D., Swientek, K., Czech, B., Kliczewski, S., Korcyl, K., Kozela, A., Kulessa, P., Lebiedowicz, P., Malgorzata, K., Pysz, K., Schäfer, W., Siudak, R., Szczurek, A., Biernat, J., Jowzaee, S., Kamys, B., Kistryn, S., Korcyl, G., Krzemien, W., Magiera, A., Moskal, P., Palka, M., Psyzniak, A., Rudy, Z., Salabura, P., Smyrski, J., Strzempek, P., Wrońska, A., Augustin, I., Lehmann, I., Nicmorus, D., Schepers, G., Schmitt, L., Al Turany, M., Cahit, U., Capozza, L., Dbeyssi, A., Deppe, H., Dzhygadlo, R., Ehret, A., Flemming, H., Gerhardt, A., Götzen, K., Karabowicz, R., Kliemt, R., Kunkel, J., Kurilla, U., Lehmann, D., Lühning, J., Maas, F., Morales Morales, C., Mora Espí, M. C., Nerling, F., Orth, H., Peters, K., Rodríguez Piñeiro, D., Saito, N., Saito, T., Sánchez Lorente, A., Schmidt, C. J., Schwarz, C., Schwiening, J., Traxler, M., Valente, R., Voss, B., Wieczorek, P., Wilms, A., Zühlsdorf, M., Abazov, V. M., Alexeev, G., Arefiev, A., Astakhov, V. I., Barabanov, M. Y. u., Batyunya, B. V., Davydov, Y. u. I., Dodokhov, V. K. h., Efremov, A. A., Fedunov, A. G., Festchenko, A. A., Galoyan, A. S., Grigoryan, S., Karmokov, A., Koshurnikov, E. K., Lobanov, V. I., Lobanov, Y. u. Y. u., Makarov, A. F., Malinina, L. V., Malyshev, V. L., Mustafaev, G. A., Olshevskiy, A., Pasyuk, M. A., Perevalova, E. A., Piskun, A. A., Pocheptsov, T. A., Pontecorvo, G., Rodionov, V. K., Rogov, Y. u. N., Salmin, R. A., Samartsev, A. G., Sapozhnikov, M. G., Shabratova, G. S., Skachkov, N. B., Skachkova, A. N., Strokovsky, E. A., Suleimanov, M. K., Teshev, R. S. h., Tokmenin, V. V., Uzhinsky, V. V., Vodopyanov, A. S., Zaporozhets, S. A., Zhuravlev, N. I., Zorin, A. G., Branford, D., Glazier, D., Watts, D., Woods, P., Britting, A., Eyrich, W., Lehmann, A., Uhlig, F., Dobbs, S., Seth, K., Tomaradze, A., Xiao, T., Bettoni, D., Carassiti, V., Cotta Ramusino, A., Dalpiaz, P., Drago, A., Fioravanti, E., Garzia, I., Savriè, M., Stancari, G., Akishina, V., Kisel, I., Kulakov, I., Zyzak, M., Arora, R., Bel, T., Gromliuk, A., Kalicy, G., Krebs, M., Patsyuk, M., Zuehlsdorf, M., Bianchi, N., Gianotti, P., Guaraldo, C., Lucherini, V., Pace, E., Bersani, A., Bracco, G., Macri, M., Parodi, R. F., Bianco, S., Bremer, D., Brinkmann, K. T., Diehl, S., Dormenev, V., Drexler, P., Düren, M., Eissner, T., Etzelmüller, E., Föhl, K., Galuska, M., Gessler, T., Gutz, E., Hayrapetyan, A., Hu, J., Kröck, B., Kühn, W., Kuske, T., Lange, S., Liang, Y., Merle, O., Metag, V., Mülhheim, D., Münchow, D., Nanova, M., Novotny, R., Pitka, A., Quagli, T., Rieke, J., Rosenbaum, C., Schnell, R., Spruck, B., Stenzel, H., Thöring, U., Ullrich, M., Wasem, T., Werner, M., Zaunick, H. G., Ireland, D., Rosner, G., Seitz, B., Deepak, P. N., Kulkarni, A. V., Apostolou, A., Babai, M., Kavatsyuk, M., Lemmens, P., Lindemulder, M., Löhner, H., Messchendorp, J., Schakel, P., Smit, H., van der Weele, J. C., Tiemens, M., Veenstra, R., Vejdani, S., Kalita, K., Mohanta, D. P., Kumar, A., Roy, A., Sahoo, R., Sohlbach, H., Büscher, M., Cao, L., Cebulla, A., Deermann, D., Dosdall, R., Esch, S., Georgadze, I., Gillitzer, A., Goerres, A., Goldenbaum, F., Grunwald, D., Herten, A., Hu, Q., Kemmerling, G., Kleines, H., Kozlov, V., Lehrach, A., Leiber, S., Maier, R., Nellen, R., Ohm, H., Orfanitski, S., Prasuhn, D., Prencipe, E., Ritman, J., Schadmand, S., Schumann, J., Sefzick, T., Serdyuk, V., Sterzenbach, G., Stockmanns, T., Wintz, P., Wüstner, P., Xu, H., Li, S., Li, Z., Sun, Z., Rigato, V., Fissum, S., Hansen, K., Isaksson, L., Lundin, M., Schröder, B., Achenbach, P., Bleser, S., Cardinali, M., Corell, O., Deiseroth, M., Denig, A., Distler, M., Feldbauer, F., Fritsch, M., Jasinski, P., Hoek, M., Kangh, D., Karavdina, A., Lauth, W., Leithoff, H., Merkel, H., Michel, M., Motzko, C., Müller, U., Noll, O., Plueger, S., Pochodzalla, J., Sanchez, S., Schlimme, S., Sfienti, C., Steinen, M., Thiel, M., Weber, T., Zambrana, M., Dormenev, V. I., Fedorov, A. A., Korzihik, M. V., Missevitch, O. V., Balanutsa, P., Balanutsa, V., Chernetsky, V., Demekhin, A., Dolgolenko, A., Fedorets, P., Gerasimov, A., Goryachev, V., Varentsov, V., Boukharov, A., Malyshev, O., Marishev, I., Semenov, A., Konorov, I., Paul, S., Grieser, S., Hergemöller, A. K., Khoukaz, A., Köhler, E., Täschner, A., Wessels, J., Dash, S., Jadhav, M., Kumar, S., Sarin, P., Varma, R., Chandratre, V. B., Datar, V., Dutta, D., Jha, V., Kumawat, H., Mohanty, A. K., Roy, B., Yan, Y., Chinorat, K., Khanchai, K., Ayut, L., Pornrad, S., Barnyakov, A. Y., Blinov, A. E., Blinov, V. E., Bobrovnikov, V. S., Kononov, S. A., Kravchenko, E. A., Kuyanov, I. A., Onuchin, A. P., Sokolov, A. A., Tikhonov, Y. A., Atomssa, E., Hennino, T., Imre, M., Kunne, R., Le Galliard, C., Ma, B., Marchand, D., Ong, S., Ramstein, B., Rosier, P., Tomasi Gustafsson, E., Van de Wiele, J., Boca, G., Costanza, S., Genova, P., Lavezzi, L., Montagna, P., Rotondi, A., Abramov, V., Belikov, N., Bukreeva, S., Davidenko, A., Derevschikov, A., Goncharenko, Y., Grishin, V., Kachanov, V., Kormilitsin, V., Melnik, Y., Levin, A., Minaev, N., Mochalov, V., Morozov, D., Nogach, L., Poslavskiy, S., Ryazantsev, A., Ryzhikov, S., Semenov, P., Shein, I., Uzunian, A., Vasiliev, A., Yakutin, A., Yabsley, B., Bäck, T., Cederwall, B., Makónyi, K., Tegnér, P. E., von Würtemberg, K. M., Belostotski, S., Gavrilov, G., Izotov, A., Kashchuk, A., Levitskaya, O., Manaenkov, S., Miklukho, O., Naryshkin, Y., Suvorov, K., Veretennikov, D., Zhadanov, A., Rai, A. K., Godre, S. S., Duchat, R., Amoroso, A., Bussa, M. P., Busso, L., De Mori, F., Destefanis, M., Fava, L., Ferrero, L., Greco, M., Maggiora, M., Maniscalco, G., Marcello, S., Sosio, S., Spataro, S., Zotti, L., Calvo, D., Coli, S., De Remigis, P., Filippi, A., Giraudo, G., Lusso, S., Mazza, G., Mingnore, M., Rivetti, A., Wheadon, R., Balestra, F., Iazzi, F., Introzzi, R., Lavagno, A., Younis, H., Birsa, Renato, Bradamante, Franco, Bressan, Andrea, Martin, Anna, Clement, H., Gålnander, B., Caldeira Balkeståhl, L., Calén, H., Fransson, K., Johansson, T., Kupsc, A., Marciniewski, P., Pettersson, J., Schönning, K., Wolke, M., Zlomanczuk, J., Díaz, J., Ortiz, A., Vinodkumar, P. C., Parmar, A., Chlopik, A., Melnychuk, D., Slowinski, B., Trzcinski, A., Wojciechowski, M., Wronka, S., Zwieglinski, B., Bühler, P., Marton, J., Suzuki, K., Widmann, E., Zmeskal, J., Fröhlich, B., Khaneft, D., Lin, D., Zimmermann, I., and Semenov Tian Shansky, K.

Subjects
Particle physics, (P)Over-Baranda, Nuclear and High Energy Physics, Electroproduction, Hadron, Annihilation, FOS: Physical sciences, 7. Clean energy, 01 natural sciences, Particle identification, Nucleon, NO, Nuclear physics, High Energy Physics - Experiment (hep-ex), High Energy Physics - Phenomenology (hep-ph), Factorization, 0103 physical sciences, Fysik, Invariant mass, ddc:530, Meson Production, Monte-Carlo, Nuclear Experiment (nucl-ex), 010306 general physics, Nuclear Experiment, Physics, Quantum chromodynamics, 010308 nuclear & particles physics, Perturbative QCD, Qcd, Physical Sciences, Exclusive Processes, High Energy Physics::Experiment, Pi(0), Cross-Sections, Energy (signal processing)
Abstract

Baryon-to-meson Transition Distribution Amplitudes (TDAs) encoding valuable new information on hadron structure appear as building blocks in the collinear factorized description for several types of hard exclusive reactions. In this paper, we address the possibility of accessing nucleon-to-pion ($��N$) TDAs from $\bar{p}p \to e^+e^- ��^0$ reaction with the future PANDA detector at the FAIR facility. At high center of mass energy and high invariant mass squared of the lepton pair $q^2$, the amplitude of the signal channel $\bar{p}p \to e^+e^- ��^0$ admits a QCD factorized description in terms of $��N$ TDAs and nucleon Distribution Amplitudes (DAs) in the forward and backward kinematic regimes. Assuming the validity of this factorized description, we perform feasibility studies for measuring $\bar{p}p \to e^+e^- ��^0$ with the PANDA detector. Detailed simulations on signal reconstruction efficiency as well as on rejection of the most severe background channel, i.e. $\bar{p}p \to ��^+��^- ��^0$ were performed for the center of mass energy squared $s = 5$ GeV$^2$ and $s = 10$ GeV$^2$, in the kinematic regions $3.0 < q^2 < 4.3$ GeV$^2$ and $5 < q^2 < 9$ GeV$^2$, respectively, with a neutral pion scattered in the forward or backward cone $| \cos��_{��^0}| > 0.5 $ in the proton-antiproton center of mass frame. Results of the simulation show that the particle identification capabilities of the PANDA detector will allow to achieve a background rejection factor of $5\cdot 10^7$ ($1\cdot 10^7$) at low (high) $q^2$ for $s=5$ GeV$^2$, and of $1\cdot 10^8$ ($6\cdot 10^6$) at low (high) $q^2$ for $s=10$ GeV$^2$, while keeping the signal reconstruction efficiency at around $40\%$. At both energies, a clean lepton signal can be reconstructed with the expected statistics corresponding to $2$ fb$^{-1}$ of integrated luminosity. (.../...), 19 pages, 7 figures (some multiple), 2 tables (each double), preprint of an article for epj - v2

Published
2015

42. Phase motion of baryon resonances

Author

U. Thoma, A. V. Anisovich, V. A. Nikonov, A. V. Sarantsev, and Eberhard Klempt

Subjects
Novel technique, Physics, Nuclear and High Energy Physics, Nuclear Theory, Hadron, Phase (waves), Motion (geometry), Baryon, Nuclear physics, Amplitude, Quantum electrodynamics, Nuclear fusion, High Energy Physics::Experiment, Nuclear Experiment
Abstract

A novel technique to probe the resonant structure of a partial-wave amplitude is proposed and applied to data on photoproduction of baryon resonances.

Published
2006

43. Decays of baryon resonances into ΛK+, ΣK+ and Σ+K0

Author

A. V. Sarantsev, A. V. Anisovich, U. Thoma, Eberhard Klempt, and V. A. Nikonov

Subjects
Baryon, Physics, Nuclear and High Energy Physics, Particle physics, Recoil, Nuclear Theory, Sigma, High Energy Physics::Experiment, Nuclear Experiment, Lambda, Beam (structure)
Abstract

Cross sections, beam asymmetries, and recoil polarisations for the reactions gamma p to K^+ Lambda ; gamma to K^+ Sigma^0, and gamma p to K^0 Sigma^+ have been measured by the SAPHIR, CLAS, and LEPS collaborations with high statistics and good angular coverage for centre-of-mass energies between 1.6 and 2.3 GeV. The combined analysis of these data with data from pi and eta photoproduction reveals evidence for new baryon resonances in this energy region. A new P_{11} state with mass 1840 MeV and width 140 MeV was observed contributing to most of the fitted reactions. The data demand the presence of two D_{13} states at 1870 and 2170 MeV.

Published
2005

44. Study of antiproton annihilation on neutrons into ωπ−π0

Author

M. Suffert, T. Case, H. Kalinowsky, V. Crede, K.M. Crowe, F. Meyer-Wildhagen, R. Landua, C. Regenfus, D. Jamnik, D. Engelhardt, R. Ouared, U. Kurilla, S. Wallis-Plachner, R. P. Haddock, N.P. Hessey, C.A. Baker, C.J. Batty, P. Blüm, K. Peters, Eberhard Klempt, M. A. Faessler, C. A. Meyer, A. V. Sarantsev, M. Benayoun, J. Kisiel, U. Wiedner, Bruce Barnett, D. Walther, U. Thoma, I. Uman, U. Strohbusch, A. V. Anisovich, H. Matthäy, Herbert Koch, Michael Doser, K. Wittmack, J. Reinnarth, K. Braune, P. Kammel, B. Pick, W. Dünnweber, Claude Amsler, F. H. Heinsius, J.S. Suh, Marcel Kunze, Pàl Hidas, and M. Ratajczak

Subjects
Physics, Nuclear physics, Crystal, Nuclear and High Energy Physics, Particle physics, Annihilation, Large Hadron Collider, Deuterium, Antiproton, Partial wave analysis, Neutron, Nuclear Experiment, Spectroscopy
Abstract

Data are presented on antiproton neutron annihilation at rest into ωπ − π 0 taken with the Crystal Barrel detector at LEAR (CERN) using a liquid deuterium target. The partial wave analysis shows evidence for at least two ωπ vector resonances above the ρ (770) ground-state. Possible evidence for a third ρ ′ state with a mass around 1180 MeV is discussed. The results are compared to model dependent predictions concerning the nature of the ρ ′ states.

Published
2004

45. Annihilation at rest of antiprotons and protons into neutral particles

Author

M. Suffert, C.J. Batty, A. V. Anisovich, V. Crede, U. Thoma, H. Kalinowsky, N.P. Hessey, J.S. Suh, C.A. Baker, C. A. Meyer, M. Heinzelmann, W. Dünnweber, Michael Doser, F. H. Heinsius, D. Jamnik, R. Landua, S. Wallis-Plachner, D. Engelhardt, M. Benayoun, M. A. Faessler, Marcel Kunze, Herbert Koch, Kenneth M. Crowe, K. Wittmack, B. Pick, S. Spanier, K. Peters, D. Walther, B. S. Zou, Claude Amsler, J. Kisiel, U. Strohbusch, U. Wiedner, U. Kurilla, K. Braune, Pàl Hidas, I. Uman, A. V. Sarantsev, P. Kammel, B.M. Barnett, W. Popkov, L. Montanet, R. P. Haddock, P. Blüm, D.V. Bugg, J. Reinnarth, T. Case, H. Matthäy, M. Ratajczak, W. Roethel, Eberhard Klempt, R. Ouared, F. Meyer-Wildhagen, and C. Regenfus

Subjects
Rest (physics), Physics, Nuclear and High Energy Physics, Annihilation, Meson, 010308 nuclear & particles physics, Branching fraction, 01 natural sciences, 7. Clean energy, Nuclear physics, Crystal, Antiproton, 0103 physical sciences, High Energy Physics::Experiment, Atomic physics, Nuclear Experiment, 010306 general physics, Liquid hydrogen, Bar (unit)
Abstract

Annihilation of antiprotons and protons at rest into neutral particles has been studied with the Crystal Barrel detector at LEAR. Annihilation frequencies are determined for final states containing π 0 , η , η ′ and ω mesons using a liquid and a room temperature, 12 bar, gaseous hydrogen target. Including annihilation frequencies for production of neutral kaons from other experiments, the identified reactions for annihilation in liquid hydrogen add up to a branching fraction of (3.56±0.28)% per annihilation compared to the frequency of (3.50±0.30)% with which we observe the all-neutral decay modes inclusively. Since the exclusive final states are normalized to the Crystal Barrel measurement of the π 0 π 0 branching ratio, the latter result is strongly supported by this present study.

Published
2003

46. Spectroscopy of baryon resonances

Author

Reinhard Beck and U. Thoma

Subjects
Physics, Photon, 010308 nuclear & particles physics, QC1-999, Partial wave analysis, Nuclear Theory, Resonance, Electron, 01 natural sciences, Helicity, Baryon, Nuclear physics, 0103 physical sciences, Neutron, Atomic physics, Nuclear Experiment, 010306 general physics, Excitation
Abstract

Within project A.1 of the SFB/TR16 “Subnuclear Structure of Matter”, a large amount of data on photoproduction reactions has been accumulated at the Bonn Electron Stretcher Accelerator ELSA with the CBELSA/TAPS detector and was analysed in detail. In particular, data have been taken with unpolarized or with linearly or circularly polarized photons and with unpolarized or with longitudinally or transversely polarized protons. Photoproduction off neutrons was studied to determine the helicity amplitudes for the excitation of resonances off neutrons. In a partial wave analysis of the data, new resonances have been found and the properties of new and of known resonances have been determined, including the measurement of partial widths of so far unmeasured decay modes.

Published
2017

47. N(1520)3/2−Helicity Amplitudes from an Energy-Independent Multipole Analysis Based on New Polarization Data on Photoproduction of Neutral Pions

Author

Ph. Thämer, Ch. Honisch, Ch. Schmidt, J. Hannappel, A. V. Anisovich, V. A. Nikonov, A. V. Sarantsev, H. Schmieden, Alastair J. Wilson, T. C. Jude, Ulrich Wiedner, D. E. Bayadilov, Lilian Witthauer, A. B. Gridnev, Mariana Nanova, M. Kube, A. Thiel, A. Käser, U. Thoma, K. Makonyi, Francesco Messi, K.-Th. Brinkmann, M. Grüner, Ch. Hammann, Matthew Lang, K. Fornet-Ponse, H. van Pee, K. Koop, M. Becker, Yu. A. Beloglazov, S. Böse, H. Kalinowsky, G. Reicherz, A. Berlin, E. Gutz, D. V. Novinski, Friedrich Klein, F. Kalischewski, A. Winnebeck, P. Klassen, M. Urban, T. Rostomyan, M. Gottschall, D. Elsner, D. Walther, V. Sokhoyan, W. Meyer, V. Metag, T. Seifen, R. W. Novotny, Ph. Hoffmeister, Ch. Funke, B. Krusche, Friedrich, Eberhard Klempt, B. Roth, M. Bichow, Reinhard Beck, Wolfgang Hillert, M. Dieterle, Y. Wunderlich, Ch. Wendel, Frank Frommberger, D. Piontek, I. V. Lopatin, H. Dutz, H. Eberhardt, V. Crede, I. Keshelashvili, Jörg H. Müller, Jens Hartmann, D. Kaiser, R. Schmitz, C. Rosenbaum, O. Jahn, V. Hannen, and J. Herick

Subjects
Physics, 010308 nuclear & particles physics, Linear polarization, Partial wave analysis, General Physics and Astronomy, Electron, Polarization (waves), 01 natural sciences, Helicity, Nuclear physics, Amplitude, Pion, 0103 physical sciences, Nuclear Experiment, 010306 general physics, Multipole expansion
Abstract

New data on the polarization observables T, P, and H for the reaction γp→pπ0 are reported. The results are extracted from azimuthal asymmetries when a transversely polarized butanol target and a linearly polarized photon beam are used. The data were taken at the Bonn electron stretcher accelerator ELSA using the CBELSA/TAPS detector. These and earlier data are used to perform a truncated energy-independent partial wave analysis in sliced-energy bins. This energy-independent analysis is compared to the results from energy-dependent partial wave analyses.

Published
2014

48. High statistics study of the reaction γp → pπ0 η

Author

E. Gutz, A. Süle, B. Bantes, S. Lugert, D. Elsner, R. Castelijns, R. W. Novotny, H. Schmieden, Ph. Hoffmeister, Eberhard Klempt, Frank Klein, B. Krusche, D. E. Bayadilov, A. B. Gridnev, O. Bartholomy, R. Gregor, M. Kotulla, Yu. A. Beloglazov, A. Wilson, J. C. S. Bacelar, A. V. Sarantsev, M. Ostrick, D. Trnka, Matthew Lang, T. Szczepanek, Ankhi Roy, A. V. Anisovich, Lalit Mohan Pant, Frank Frommberger, R. Varma, U. Thoma, M. Fuchs, V. Crede, D. Novinsky, V. Sokhoyan, J. Junkersfeld, V. Kleber, R. Beck, H. Dutz, Wolfgang Hillert, V. A. Nikonov, S. Shende, M. Pfeiffer, Ch. Wendel, S. Kammer, V. V. Sumachev, Ch. Funke, M. Nanova, I. Jaegle, R. Ewald, A. Thiel, I. Horn, H. van Pee, H. Kalinowsky, D. Walther, T. Mertens, Herbert Löhner, V. Metag, J. G. Messchendorp, D. Piontek, Ch. Schmidt, I. V. Lopatin, and Friedrich Klein

Subjects
Physics, Nuclear and High Energy Physics, Photon, Meson, 010308 nuclear & particles physics, Partial wave analysis, Nuclear Theory, Hadron, Dalitz plot, Electron, 01 natural sciences, Nuclear physics, 0103 physical sciences, Isobar, Nuclear Experiment, 010306 general physics, Nucleon
Abstract

Photoproduction off protons of the pπ 0 η three-body final state was studied with the Crystal Barrel/TAPS detector, at the electron stretcher accelerator ELSA in Bonn, for incident energies from the π 0 η production threshold up to 2.5 GeV. Differential cross sections and the total cross sections are presented. The use of linearly polarized photons gives access to the polarization observables Σ, I s , and I c , the latter two characterize beam asymmetries in case of three-body final states. Δ(1232)η, N(1535)1/2− π, and pa 0(980) are the dominant isobars contributing to the reaction. The partial wave analysis confirms the existence of some nucleon and Δ resonances, for which so far only fair evidence was reported. A large number of decay modes of known nucleon and Δ resonances is presented. It is shown that detailed investigations of decay branching ratios may provide a key to unravelling the structure of nucleon and Δ resonances.

Published
2014

49. First Measurement of the Helicity Asymmetry forγp→pπ0in the Resonance Region

Author

R. W. Novotny, Ph. Hoffmeister, K. Makonyi, A. V. Anisovich, K.-Th. Brinkmann, K. Fornet-Ponse, H. van Pee, K. Koop, Frank Klein, M. Urban, V. Crede, Matthew Lang, Friedrich, A. Wilson, V. Sokhoyan, Yasser Maghrbi, H. Dutz, R. Schmitz, R. Ewald, D. Piontek, R. Beck, W. Meyer, G. Reicherz, H. Schmieden, D. E. Bayadilov, H. Eberhardt, I. V. Lopatin, T. Seifen, H. Kalinowsky, A. B. Gridnev, Mariana Nanova, J. Hannappel, D. Kaiser, I. Jaegle, J. Mueller, Ulrich Wiedner, U. Thoma, M. Gruener, Frank Frommberger, Jens Hartmann, Wolfgang Hillert, V. Metag, M. Gottschall, T. Rostomyan, E. Gutz, I. Keshelashvili, M. Bichow, A. V. Sarantsev, D. Walther, B. Bantes, S. Boese, V. A. Nikonov, A. Thiel, Eberhard Klempt, Ch. Hammann, A. Winnebeck, M. Kube, Ch. Honisch, Ch. Schmidt, S. Kammer, F. Dietz, Th. Challand, Ch. Funke, B. Krusche, Ch. Wendel, Schaepe, and D. Elsner

Subjects
Physics, Photon, 010308 nuclear & particles physics, media_common.quotation_subject, Nuclear Theory, Solid angle, General Physics and Astronomy, Resonance, 01 natural sciences, Asymmetry, Helicity, Nuclear physics, Cross section (physics), Amplitude, Pion, 0103 physical sciences, Nuclear Experiment, 010306 general physics, media_common
Abstract

The first measurement of the helicity dependence of the photoproduction cross section of single neutral pions off protons is reported for photon energies from 600 to 2300 MeV, covering nearly the full solid angle. The data are compared to predictions from the SAID, MAID, and BnGa partial wave analyses. Strikingly large differences between data and predictions are observed, which are traced to differences in the helicity amplitudes of well-known and established resonances. Precise values for the helicity amplitudes of several resonances are reported.

Published
2014

50. Rescattering effects in $\phi$ photoproduction

Author

U. Thoma and A.V. Anisovich

Subjects
Physics, Particle physics, Physics and Astronomy (miscellaneous), Meson, High Energy Physics::Phenomenology, Nuclear Theory, Scalar (mathematics), Strangeness, Lambda, High Energy Physics::Experiment, Nuclear Experiment, Nucleon, Wave function, Engineering (miscellaneous)
Abstract

We calculate the contribution from rescattering of \(\mbox{K}^+\mbox{K}^-\) pairs produced by photoproduction of \(\Lambda(1520)\mbox{K}^+\) to the photoproduction of \(\phi\) mesons. The photoproduction of \(\phi\) mesons is presently a hot topic due to the possibility that an intrinsic hidden strangeness contribution in the nucleon flavor wave function may be revealed in this process, and due to the possibility that the structure of scalar mesons could be accessible experimentally via \(S-P\) interference in the \(\mbox{K}^+\mbox{K}^-\) system. We show that rescattering makes an important contribution to \(\phi\) photoproduction which could – if neglected – mislead the interpretation of the forthcoming high precision data.

Published
2001

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