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122 results on '"M. O. Distler"'

1. The influence of Fermi motion on the comparison of the polarization transfer to a proton in elastic e→p and quasi-elastic e→A scattering

Author

T. Brecelj, F. Schulz, U. Müller, A. Tyukin, Michaela Thiel, Concettina Sfienti, Anselm Esser, D. G. Middleton, J. Beričič, Guy Ron, Hartmuth Arenhövel, Ronald Gilman, J. Pochodzalla, Harald Merkel, M. Olivenboim, S. Strauch, B. S. Schlimme, M. Mihovilovič, R. Böhm, D. Izraeli, Israel Mardor, S. Širca, S. Štajner, Ivica Friščić, A. Weber, L. Debenjak, J. Lichtenstadt, I. Yaron, E. Piasetzky, M. Schoth, Patrick Achenbach, M. O. Distler, I. Korover, Adi Ashkenazi, S.J. Paul, D. Bosnar, T. Kolar, and Eliahu Cohen

Subjects
Physics, Elastic scattering, Nuclear and High Energy Physics, 010308 nuclear & particles physics, Scattering, Initial momentum, Nuclear Theory, Kinematics, Polarization (waves), 01 natural sciences, 7. Clean energy, Transverse plane, 0103 physical sciences, Physics::Accelerator Physics, Atomic physics, Nuclear Experiment, 010306 general physics, Microtron, Fermi Gamma-ray Space Telescope
Abstract

A comparison between polarization-transfer to a bound proton in quasi-free kinematics by the A ( e → , e ′ p → ) knockout reaction and that in elastic scattering off a free proton can provide information on the characteristics of the bound proton. In the past the reported measurements have been compared to those of a free proton with zero initial momentum. We introduce, for the first time, expressions for the polarization-transfer components when the proton is initially in motion and compare them to the 2H data measured at the Mainz Microtron (MAMI). We show the ratios of the transverse ( P x ) and longitudinal ( P z ) components of the polarization transfer in H 2 ( e → , e ′ p → ) n , to those of elastic scattering off a “moving proton”, assuming the proton's initial (Fermi-motion) momentum equals the negative missing momentum in the measured reaction. We found that the correction due to the proton motion is up to 20% at high missing momentum. However the effect on the double ratio ( P x / P z ) A ( P x / P z ) H 1 is largely canceled out, as shown for both 2H and 12C data. This implies that the difference between the resting- and the moving-proton kinematics is not the primary cause for the deviations between quasi-elastic and elastic scattering reported previously.

Published
2019

2. Operation and characterization of a windowless gas jet target in high-intensity electron beams

Author

A. G. Denig, M. Christmann, A. Khoukaz, H. Schürg, J. Marekovič, J. Müller, Luca Doria, U. Müller, M. Littich, M. Biroth, P. Herrmann, C. Vidal, J. Schlaadt, J. Kelsey, Anselm Esser, P. Klag, P. Gülker, M. Hoek, R. Spreckels, Concettina Sfienti, S. Grieser, D. Markus, Ethan Cline, T. Petrovič, C. Szyszka, S. Aulenbacher, P. Eckert, S. Širca, Ross Milner, Ivica Friščić, Yi-Nan Wang, J. Rausch, Michaela Thiel, J. Geimer, S. Lunkenheimer, S. Vestrick, T. Kolar, Markus Ball, Y. Stöttinger, P. Brand, B. S. Schlimme, M. Mauch, Michael Kohl, M. Mihovilovič, M. O. Distler, D. Bonaventura, L. Leßmann, Magix Collaborations, S. Kegel, S. Gagneur, S. Stengel, J. Pochodzalla, Harald Merkel, M. Lauß, D. Bosnar, Jan C. Bernauer, Patrick Achenbach, and S. Caiazza

Subjects
Nuclear and High Energy Physics, Physics - Instrumentation and Detectors, Nuclear engineering, chemistry.chemical_element, FOS: Physical sciences, Electron, 01 natural sciences, law.invention, Xenon, law, 0103 physical sciences, Nuclear Experiment (nucl-ex), 010306 general physics, Instrumentation, Nuclear Experiment, Helium, Physics, Jet (fluid), Argon, 010308 nuclear & particles physics, Particle accelerator, Instrumentation and Detectors (physics.ins-det), chemistry, Physics::Accelerator Physics, Electron scattering, Beam (structure)
Abstract

A cryogenic supersonic gas jet target was developed for the MAGIX experiment at the high-intensity electron accelerator MESA. It will be operated as an internal, windowless target in the energy-recovering recirculation arc of the accelerator with different target gases, e.g., hydrogen, deuterium , helium, oxygen, argon, or xenon. Detailed studies have been carried out at the existing A1 multi-spectrometer facility at the electron accelerator MAMI. This paper focuses on the developed handling procedures and diagnostic tools, and on the performance of the gas jet target under beam conditions. Considering the special features of this type of target, it proves to be well suited for a new generation of high-precision electron scattering experiments at high-intensity electron accelerators .

Published
2021

3. 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

4. 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

5. 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

6. Polarization transfer to bound protons measured by quasi-elastic electron scattering on $^{12}$C

Author

S. Strauch, T. Kolar, Eli Piasetzky, Concettina Sfienti, T. Brecelj, J. Lichtenstadt, I. Yaron, S.J. Paul, Simon Širca, Adi Ashkenazi, Carlotta Giusti, M. Mihovilovic, S. Štajner, M. Schoth, Anselm Esser, I. Korover, B. S. Schlimme, F. Schulz, Guy Ron, Michaela Thiel, P. Achenbach, D. Izraeli, M. O. Distler, E.O. Cohen, U. Müller, R. Böhm, Israel Mardor, Ronald Gilman, Harald Merkel, Adrian Weber, and M. Olivenboim

Subjects
Physics, Proton, 010308 nuclear & particles physics, Nuclear Theory, FOS: Physical sciences, Polarization (waves), 01 natural sciences, Transverse plane, 0103 physical sciences, Atomic physics, Nuclear Experiment (nucl-ex), 010306 general physics, Nuclear Experiment, Electron scattering
Abstract

We report the measurements of the transverse ($P'x$) and longitudinal ($P'z$) components of the polarization transfer to a bound proton in carbon via the quasi-free $^{12}{\rm C}(\vec e,e'\vec p)$ reaction, over a wide range of missing momenta. We determine these polarization-transfers separately for protons knocked out from the $s$- and $p$-shells. The electron-beam polarization was measured to determine the individual components with systematic uncertainties which allow a detailed comparison with theoretical calculations.

Published
2020

7. Measurement of the Generalized Polarizabilities of the Proton at Intermediate $Q^2$

Author

J. Beričič, Y. Kohl, A. Blomberg, Patrick Achenbach, L. Nungesser, Jan C. Bernauer, Simon Širca, F. Schulz, A. Tyukin, M. Benali, M. O. Distler, Nikos Sparveris, D. G. Middleton, Concettina Sfienti, Damir Bosnar, L. Debenjak, Michael Paolone, M. Mihovilovic, A. C. Weber, L. Correa, M. Schoth, B. S. Schlimme, E. J. Downie, M. Weinriefer, H. Fonvieille, Anselm Esser, U. Müller, Harald Merkel, Ivica Friščić, Michaela Thiel, S. Kegel, J. Pochodzalla, S. Štajner, Mihael Makek, S. Sánchez Majos, C. Ayerbe Gayoso, A. G. Denig, R. Böhm, Laboratoire de Physique de Clermont (LPC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA), and A1

Subjects
MAINZ-A1, Proton, Nuclear Theory, [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], higher-order, Hadronic Physics and QCD, FOS: Physical sciences, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], momentum transfer dependence, 01 natural sciences, electron p: scattering, Nuclear Theory (nucl-th), Cross section (physics), High Energy Physics - Phenomenology (hep-ph), Polarizability, 0103 physical sciences, Calibration, p: structure function, Nuclear Experiment (nucl-ex), 010306 general physics, Microtron, Nuclear Experiment, Physics, 010308 nuclear & particles physics, Compton scattering, Observable, cross section: measured, calibration, Computational physics, High Energy Physics - Phenomenology, [PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph], p: polarizability, +electron+p+photon%22">electron p --> electron p photon, Nucleon, experimental results
Abstract

Background: Generalized polarizabilities (GPs) are important observables to describe the nucleon structure, and measurements of these observables are still scarce. Purpose: This paper presents details of a virtual Compton scattering (VCS) experiment, performed at the A1 setup at the Mainz Microtron by studying the $e p \to e p \gamma$ reaction. The article focuses on selected aspects of the analysis. Method: The experiment extracted the $P_{LL} -P_{TT} / \epsilon$ and $P_{LT}$ structure functions, as well as the electric and magnetic GPs of the proton, at three new values of the four-momentum transfer squared $Q^2$: 0.10, 0.20 and 0.45 GeV$^2$. Results: We emphasize the importance of the calibration of experimental parameters. The behavior of the measured $e p \to e p \gamma$ cross section is presented and compared to the theory. A detailed investigation of the polarizability fits reveals part of their complexity, in connection with the higher-order terms of the low-energy expansion. Conclusions: The presented aspects are elements which contribute to minimize the systematic uncertainties and improve the precision of the physics results., Comment: 16 pages, 15 figures, Version 4, regular article to appear in Phys.Rev.C, more final version of some figures

Published
2020
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8. Measurements of the electron-helicity asymmetry in the quasi-elastic A(e→,e′p) process

Author

Concettina Sfienti, D. Bosnar, Anselm Esser, I. Korover, Guy Ron, P. Klag, T. Kolar, M. Hoek, M. Heilig, Adi Ashkenazi, A. Tyukin, T. Brecelj, Patrick Achenbach, M. Schoth, Michaela Thiel, D. Izraeli, F. Schulz, M. Mihovilovič, R. Spreckels, S. Strauch, R. Böhm, Israel Mardor, J. Beričič, J. Müller, U. Müller, S. Kegel, A. Weber, J. Pochodzalla, D. G. Middleton, Carlotta Giusti, M. Olivenboim, Y. Stöttinger, B. S. Schlimme, E. Piasetzky, Hartmuth Arenhövel, E. Cline, S.J. Paul, M. O. Distler, S. Širca, Ivica Friščić, S. Štajner, Ronald Gilman, J. Lichtenstadt, Eliahu Cohen, I. Yaron, and Harald Merkel

Subjects
Physics, Nuclear and High Energy Physics, Missing energy, Proton, 010308 nuclear & particles physics, Scattering, Antisymmetric relation, media_common.quotation_subject, Electron, 01 natural sciences, Helicity, Asymmetry, 3. Good health, Momentum, 0103 physical sciences, Atomic physics, 010306 general physics, media_common
Abstract

We present measurements of the electron helicity asymmetry in quasi-elastic proton knockout from 2H and 12C nuclei by polarized electrons. This asymmetry depends on the fifth structure function, is antisymmetric with respect to the scattering plane, and vanishes in the absence of final-state interactions, and thus it provides a sensitive tool for their study. Our kinematics cover the full range in off-coplanarity angle ϕ p q , with a polar angle θ p q coverage up to about 8°. The missing energy resolution enabled us to determine the asymmetries for knock-out resulting in different states of the residual 11B system. We find that the helicity asymmetry for p-shell knockout from 12C depends on the final state of the residual system and is relatively large (up to ≈0.16), especially at low missing momentum. It is considerably smaller (up to ≈0.01) for s-shell knockout from both 12C and 2H. The data for 2H are in very good agreement with theoretical calculations, while the predictions for 12C exhibit differences with respect to the data.

Published
2022

9. Polarization-transfer measurement to a large-virtuality bound proton in the deuteron

Author

J. Lichtenstadt, I. Yaron, Anselm Esser, Guy Ron, A. Weber, J. Pochodzalla, J. Beričič, A. Tyukin, M. Schoth, R. Böhm, F. Schulz, Hartmuth Arenhövel, E. Piasetzky, B. S. Schlimme, P. Achenbach, Damir Bosnar, L. Debenjak, M. Mihovilovic, Concettina Sfienti, U. Müller, D. G. Middleton, Ronald Gilman, Harald Merkel, S. Strauch, D. Izraeli, S. Širca, Ivica Friščić, Michaela Thiel, M. O. Distler, E.O. Cohen, and I. Korover

Subjects
Physics, Nuclear and High Energy Physics, Proton, 010308 nuclear & particles physics, Nuclear Theory, FOS: Physical sciences, Polarization (waves), 01 natural sciences, NATURAL SCIENCES. Physics, lcsh:QC1-999, Nuclear physics, PRIRODNE ZNANOSTI. Fizika, Deuterium, 0103 physical sciences, d(e, e’p), Electron-scattering, Physics::Accelerator Physics, Nuclear Experiment (nucl-ex), 010306 general physics, Nuclear Experiment, d(e,e'p), Electron scattering, Nuclear density, lcsh:Physics
Abstract

Possible differences between free and bound protons may be observed in the ratio of polarization-transfer components, $P'_x/P'_z$. We report the measurement of $P'_x/P'_z$, in the $^2\textrm{H}(\vec{e},e^{\prime}\vec{p})n$ reaction at low and high missing momenta. Observed increasing deviation of $P'_x/P'_z$ from that of a free proton as a function of the virtuality, similar to that observed in \hefour, indicates that the effect in nuclei is due to the virtuality of the knock-out proton and not due to the average nuclear density. The measured differences from calculations assuming free-proton form factors ($\sim10\%$), may indicate in-medium modifications., 4 figures

Published
2017

10. Quasi-elastic polarization-transfer measurements on the deuteron in anti-parallel kinematics

Author

I. Korover, Concettina Sfienti, B. S. Schlimme, E. Cline, E. Piasetzky, Eliahu Cohen, A. Weber, M. Heilig, Anselm Esser, M. O. Distler, J. Müller, T. Kolar, M. Schoth, Guy Ron, S. Širca, Ivica Friščić, D. Bosnar, F. Schulz, J. Lichtenstadt, U. Müller, I. Yaron, T. Brecelj, S. Strauch, S. Štajner, Michaela Thiel, R. Böhm, Israel Mardor, Ronald Gilman, J. Beričič, Adi Ashkenazi, Harald Merkel, L. Debenjak, M. Mihovilovič, S.J. Paul, S. Kegel, J. Pochodzalla, M. Olivenboim, P. Klag, Y. Kohl, D. G. Middleton, A. Tyukin, D. Izraeli, Patrick Achenbach, and Hartmuth Arenhövel

Subjects
Physics, Nuclear and High Energy Physics, 010308 nuclear & particles physics, Nuclear Theory, FOS: Physical sciences, Kinematics, Polarization (waves), 01 natural sciences, lcsh:QC1-999, NATURAL SCIENCES. Physics, PRIRODNE ZNANOSTI. Fizika, Parallel kinematics, Nuclear physics, Deuterium, 0103 physical sciences, ddc:530, Nuclear Experiment (nucl-ex), 010306 general physics, Nucleon, Nuclear Experiment, GeneralLiterature_REFERENCE(e.g.,dictionaries,encyclopedias,glossaries), Microtron, lcsh:Physics, polarization-transfer, deuteron, anti-parallel kinematics
Abstract

We present measurements of the polarization-transfer components in the H2(e→,e′p→) reaction, covering a previously unexplored kinematic region with large positive (anti-parallel) missing momentum, pmiss, up to 220MeV/c, and Q2=0.65 (GeV/c)2. These measurements, performed at the Mainz Microtron (MAMI), were motivated by theoretical calculations which predict small final-state interaction (FSI) effects in these kinematics, making them favorable for searching for medium modifications of bound nucleons in nuclei. We find in this kinematic region that the measured polarization-transfer components Px and Pz and their ratio agree with the theoretical calculations, which use free-proton form factors. Using this, we establish upper limits on possible medium effects that modify the bound proton's form factor ratio GE/GM at the level of a few percent. We also compare the measured polarization-transfer components and their ratio for $^{2}$H to those of a free (moving) proton. We find that the universal behavior of $^{2}$H, $^{4}$He and $^{12}$C in the double ratio (Px/Pz)A(Px/Pz)H1 is maintained in the positive missing-momentum region.

Published
2019

11. Virtual Compton Scattering measurements in the nucleon resonance region

Author

Anselm Esser, B. Pasquini, Josef Pochodzalla, Harald Merkel, Adrian Weber, H. Atac, J. Beričič, M. Schoth, R. Böhm, F. Schulz, H. Fonvieille, S. Schlimme, M. Benali, Patrick Achenbach, Nikolaos Sparveris, S. Širca, Concettina Sfienti, Ivica Friščić, D. Flay, A. Polychronopoulou, Michael Paolone, L. Correa, M. Mihovilovič, M. O. Distler, U. Müller, A. Blomberg, Zein-Eddine Meziani, Y. Kohl, Laboratoire de Physique de Clermont (LPC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Clermont Auvergne (UCA)-Centre National de la Recherche Scientifique (CNRS), and Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA)

Subjects
Physics, Nuclear and High Energy Physics, Proton, 010308 nuclear & particles physics, Momentum transfer, Compton scattering, FOS: Physical sciences, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Resonance (particle physics), Nuclear physics, Amplitude, Pion, 0103 physical sciences, Quadrupole, High Energy Physics::Experiment, Nuclear Experiment (nucl-ex), 010306 general physics, Nucleon, Nuclear Experiment
Abstract

We report on new measurements of the electric Generalized Polarizability (GP) of the proton $ \alpha_{E}$αE in a kinematic region where a puzzling dependence on momentum transfer has been observed, and we have found that $ \alpha_E = (5.3 \pm 0.6_{stat} \pm 1.3_{sys}) 10^{-4}$αE=(5.3±0.6stat±1.3sys)10-4 fm3 at $ Q^{2}=0.20$Q2=0.20 (GeV/c)2. The new measurements, when considered along with the rest of the world data, suggest that $ \alpha_E$αE can be described by either a local plateau or by an enhancement in the region $ Q^2=0.20$Q2=0.20 (GeV/c)2 to 0.33 (GeV/c)2. The experiment also provides the first measurement of the Coulomb quadrupole amplitude in the $ N \rightarrow \Delta$N→Δ transition through the exploration of the $ p(e,e'p)\gamma$p(e,ep)γ reaction. The new measurement gives $ CMR = (-4.4 \pm 0.8_{stat} \pm 0.6_{sys})\%$CMR=(-4.4±0.8stat±0.6sys)% at $ Q^2=0.20$Q2=0.20 (GeV/c)2 and is consistent with the results from the pion electroproduction world data. It has been obtained using a completely different extraction method, and therefore represents a strong validation test of the world data model uncertainties.

Published
2019
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12. Measurements of the induced polarization in the quasi-elastic A(e,e′p→) process in non-coplanar kinematics

Author

Concettina Sfienti, M. Heilig, S. Strauch, M. Hoek, T. Brecelj, Ronald Gilman, T. Kolar, J. Müller, Harald Merkel, S. Širca, Patrick Achenbach, Ivica Friščić, U. Müller, D. Izraeli, S. Kegel, J. Pochodzalla, R. Spreckels, Anselm Esser, Michaela Thiel, L. Debenjak, J. Beričič, D. G. Middleton, J. Lichtenstadt, Guy Ron, D. Bosnar, Adi Ashkenazi, I. Yaron, M. Olivenboim, S. Štajner, M. Schoth, I. Korover, A. Weber, Hartmuth Arenhövel, Carlotta Giusti, B. S. Schlimme, E. Cline, F. Schulz, M. O. Distler, M. Mihovilovič, Eliahu Cohen, E. Piasetzky, R. Böhm, Israel Mardor, S.J. Paul, P. Klag, Y. Kohl, and A. Tyukin

Subjects
Physics, Nuclear and High Energy Physics, 010308 nuclear & particles physics, Plane (geometry), Scattering, Shell (structure), 7. Clean energy, 01 natural sciences, Induced polarization, p-process, Momentum, Transverse plane, Deuterium, 0103 physical sciences, Atomic physics, 010306 general physics
Abstract

We report measurements of the induced polarization P → of protons knocked out from 2H and 12C via the A ( e , e ′ p → ) reaction. We have studied the dependence of P → on two kinematic variables: the missing momentum p miss and the “off-coplanarity” angle ϕ p q between the scattering and reaction planes. For the full 360° range in ϕ p q , both the normal ( P y ) and, for the first time, the transverse ( P x ) components of the induced polarization were measured with respect to the coordinate system associated with the scattering plane. P x vanishes in coplanar kinematics, however in non-coplanar kinematics, it is on the same scale as P y . We find that the dependence on ϕ p q is sine-like for P x and cosine-like for P y . For carbon, the magnitude of the induced polarization is especially large when protons are knocked out from the p 3 / 2 shell at very small p miss . For the deuteron, the induced polarization is near zero at small | p miss | , and its magnitude increases with | p miss | . For both nuclei such behavior is reproduced qualitatively by theoretical results, driven largely by the spin-orbit part of the final-state interactions. However, for both nuclei, sizeable discrepancies exist between experiment and theory.

Published
2020

13. Comparison of recoil polarization in the C12(e→,e′p→) process for protons extracted from s and p shells

Author

M. Olivenboim, T. Kolar, R. Böhm, Israel Mardor, Michaela Thiel, M. Mihovilovič, J. Müller, M. Hoek, M. O. Distler, Concettina Sfienti, U. Müller, D. Bosnar, J. Lichtenstadt, I. Yaron, I. Korover, S. Širca, E. Piasetzky, Eliahu Cohen, Patrick Achenbach, Carlotta Giusti, B. S. Schlimme, S. Strauch, E. Cline, R. Spreckels, Y. Kohl, Anselm Esser, Guy Ron, A. Weber, T. Brecelj, D. Izraeli, S.J. Paul, Ronald Gilman, Harald Merkel, S. Štajner, S. Kegel, and J. Pochodzalla

Subjects
Physics, Nuclear and High Energy Physics, Proton, 010308 nuclear & particles physics, Initial momentum, Nuclear Theory, Impulse (physics), Polarization (waves), 01 natural sciences, p-process, Recoil, 0103 physical sciences, Atomic physics, Nuclear Experiment, 010306 general physics
Abstract

We present the first measurements of the double ratio of the polarization-transfer components ( P x ′ / P z ′ ) p / ( P x ′ / P z ′ ) s for knock-out protons from the s and p shells in C 12 measured by the C 12 ( e → , e ′ p → ) reaction in quasi-elastic kinematics. The data are compared to theoretical predictions in the relativistic distorted-wave impulse approximation. Our results show that the differences between s- and p-shell protons, observed when compared at the same initial momentum (missing momentum), largely disappear when the comparison is done at the same proton virtuality. We observe no difference in medium modifications between protons from the s and p shells with the same virtuality in spite of the large differences in the respective nuclear densities.

Published
2020

14. Ground-state binding energy of HΛ4 from high-resolution decay-pion spectroscopy

Author

Y. Takahashi, Concettina Sfienti, M. O. Distler, Masashi Kaneta, J. Beričič, S. Bleser, Harald Merkel, U. Müller, Simon Širca, M. Mihovilovic, Patrick Achenbach, M. Steinen, R. Böhm, L. G. Tang, W. Kusaka, Ivica Friščić, S. Aulenbacher, Yu Fujii, Damir Bosnar, Michaela Thiel, S. Kegel, J. Pochodzalla, Anselm Esser, A. Sanchez Lorente, Y. Kohl, H. Fonvieille, A. Weber, A. Tyukin, M. Schoth, Hiroki Kanda, F. Schulz, Kyo Tsukada, Toshiyuki Gogami, L. Correa, B. S. Schlimme, Sho Nagao, Amur Margaryan, Satoshi Nakamura, and Manami Fujita

Subjects
Physics, Nuclear and High Energy Physics, Spectrometer, 010308 nuclear & particles physics, Binding energy, 01 natural sciences, Nuclear physics, Pion, 0103 physical sciences, Symmetry breaking, 010306 general physics, Spectroscopy, Ground state, Microtron, Order of magnitude
Abstract

A systematic study on the Λ ground state binding energy of hyperhydrogen H Λ 4 measured at the Mainz Microtron MAMI is presented. The energy was deduced from the spectroscopy of mono-energetic pions from the two-body decays of hyperfragments, which were produced and stopped in a 9Be target. First data, taken in the year 2012 with a high resolution magnetic spectrometer, demonstrated an almost one order of magnitude higher precision than emulsion data, while being limited by systematic uncertainties. In 2014 an extended measurement campaign was performed with improved control over systematic effects, increasing the yield of hypernuclei and confirming the observation with two independent spectrometers and two targets of different thicknesses. The analysis of these data is in agreement with the previously published value for the H Λ 4 binding energy as well as with a consistent re-analysis of the 2012 data. When compared to the He Λ 4 binding energy from emulsion data, a large charge symmetry breaking effect in the A = 4 hypernuclear system is confirmed.

Published
2016

15. Components of polarization-transfer to a bound proton in a deuteron measured by quasi-elastic electron scattering

Author

Concettina Sfienti, S. Širca, Damir Bosnar, Ivica Friščić, A. Tyukin, E. Piasetzky, Michaela Thiel, U. Müller, Adi Ashkenazi, J. Pochodzalla, D. Izraeli, Patrick Achenbach, A. Weber, Hartmuth Arenhövel, J. Lichtenstadt, I. Yaron, B. S. Schlimme, R. Böhm, I. Korover, D. G. Middleton, Israel Mardor, S. Štajner, Anselm Esser, Guy Ron, M. Mihovilovič, M. O. Distler, E.O. Cohen, M. Olivenboim, J. Beričič, F. Schulz, S. Strauch, Ronald Gilman, Harald Merkel, and M. Schoth

Subjects
Physics, Nuclear reaction, Nuclear and High Energy Physics, Proton, 010308 nuclear & particles physics, Scattering, Hadron, Nuclear Theory, FOS: Physical sciences, Electron, Polarization (waves), 7. Clean energy, 01 natural sciences, lcsh:QC1-999, Deuterium, 0103 physical sciences, polarization-transfer, deutron, Atomic physics, Nuclear Experiment (nucl-ex), 010306 general physics, Nucleon, Nuclear Experiment, lcsh:Physics
Abstract

We report the first measurements of the transverse (Px and Py) and longitudinal (Pz) components of the polarization transfer to a bound proton in the deuteron via the H2(e→,e′p→) reaction, over a wide range of missing momentum. A precise determination of the electron beam polarization reduces the systematic uncertainties on the individual components to a level that enables a detailed comparison to a state-of-the-art calculation of the deuteron using free-proton electromagnetic form factors. We observe very good agreement between the measured and the calculated Px/Pz ratios, but deviations of the individual components. Our results cannot be explained by medium modified electromagnetic form factors. They point to an incomplete description of the nuclear reaction mechanism in the calculation.

Published
2018

16. First Measurement of the $Q^2$ Dependence of the Beam-Normal Single Spin Asymmetry for Elastic Scattering off Carbon

Author

P. Herrmann, Concettina Sfienti, S. Širca, K. Aulenbacher, M. Dehn, B. S. Schlimme, Ivica Friščić, F. E. Maas, J. Müller, J. Beričič, D. Bosnar, S. Štajner, M. Hoek, B. Spruck, U. Müller, Michaela Thiel, Kent Paschke, H. Fonvieille, A. Weber, S. Baunack, S. Kegel, M. O. Distler, J. Pochodzalla, T. Kolar, M. Mihovilovic, V. Tioukine, H. J. Kreidel, Y. Kohl, C. Palatchi, Mikhail Gorchtein, Anselm Esser, A. Tyukin, L. Correa, Patrick Achenbach, M. Schoth, Harald Merkel, S. Heidrich, F. Schulz, F. Nillius, Laboratoire de Physique de Clermont (LPC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Clermont Auvergne (UCA)-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS), and Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)

Subjects
carbon: target, electron: polarized beam, media_common.quotation_subject, General Physics and Astronomy, Electron, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], momentum transfer dependence, 01 natural sciences, Asymmetry, Mainz Linac, 0103 physical sciences, gallium: arsenic, polarization: transverse, elektronsko raspršenje, 010306 general physics, Nuclear Experiment, Spin-½, media_common, Physics, Elastic scattering, form factor: ratio, form factor: charge, exchange: two-photon, 010308 nuclear & particles physics, nucleus: target, izmjena dva fotona, electron nucleus: elastic scattering, Charge (physics), amplitude analysis, NATURAL SCIENCES. Physics, PRIRODNE ZNANOSTI. Fizika, spin: asymmetry: measured, Elektronsko raspršenje, izmjena dva fotona, Amplitude, Cover (topology), High Energy Physics::Experiment, Atomic physics, radiation: laser, Beam (structure), photoelectron, experimental results
Abstract

We report on the first Q^{2}-dependent measurement of the beam-normal single spin asymmetry A_{n} in the elastic scattering of 570 MeV vertically polarized electrons off ^{12}C. We cover the Q^{2} range between 0.02 and 0.05 GeV^{2}/c^{2} and determine A_{n} at four different Q^{2} values. The experimental results are compared to a theoretical calculation that relates A_{n} to the imaginary part of the two-photon exchange amplitude. The result emphasizes that the Q^{2} behavior of A_{n} given by the ratio of the Compton to charge form factors cannot be treated independently of the target nucleus.

Published
2018

17. Measurement of polarization-transfer to bound protons in carbon and its virtuality dependence

Author

I. Korover, M. O. Distler, E.O. Cohen, Michaela Thiel, M. Olivenboim, M. Schoth, T. Kolar, U. Müller, Concettina Sfienti, Patrick Achenbach, S. Širca, S. Strauch, B. S. Schlimme, R. Böhm, Israel Mardor, M. Mihovilovič, D. Izraeli, T. Brecelj, J. Lichtenstadt, I. Yaron, E. Piasetzky, A. Weber, S. Štajner, Anselm Esser, Guy Ron, Ronald Gilman, Harald Merkel, and Adi Ashkenazi

Subjects
Physics, Nuclear and High Energy Physics, Proton, 010308 nuclear & particles physics, Nuclear Theory, FOS: Physical sciences, Electron, Polarization (waves), 01 natural sciences, lcsh:QC1-999, Transverse plane, 0103 physical sciences, Physics::Accelerator Physics, Nuclear Experiment (nucl-ex), Atomic physics, 010306 general physics, Nuclear Experiment, Microtron, lcsh:Physics, Nuclear density
Abstract

We measured the ratio Px/Pz of the transverse to longitudinal components of polarization transferred from electrons to bound protons in C12 by the C12(e→,e′p→) process at the Mainz Microtron (MAMI). We observed consistent deviations from unity of this ratio normalized to the free-proton ratio, (Px/Pz)C12/(Px/Pz)H1, for both s- and p-shell knocked out protons, even though they are embedded in averaged local densities that differ by about a factor of two. The dependence of the double ratio on proton virtuality is similar to the one for knocked out protons from H2 and He4, suggesting a universal behavior. It further implies no dependence on average local nuclear density.

Published
2017

18. Beam helicity asymmetries in $K^{+} \Lambda$ K + Λ electroproduction off the proton at low Q2

Author

C. Rappold, D. Bosnar, Masashi Kaneta, S. Sánchez Majos, T. R. Saito, C. Ayerbe Gayoso, L. Debenjak, M. Schoth, Hiroki Kanda, Patrick Achenbach, U. Müller, Joerg Reinhold, Ivica Friščić, L. G. Tang, Kyo Tsukada, Michaela Thiel, Simon Širca, D. Skoupil, O. Borodina, S. N. Nakamura, J. Pochodzalla, Osamu Hashimoto, A. Sanchez Lorente, P. Bydžovský, F. Schulz, Concettina Sfienti, Anselm Esser, Y. Fujii, M. O. Distler, Amur Margaryan, B. S. Schlimme, V. Bozkurt, Sho Nagao, Toshiyuki Gogami, R. Böhm, E. Kim, S. Hirose, M. Gómez Rodríguez, and Harald Merkel

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Meson, 010308 nuclear & particles physics, Nuclear Theory, Hadron, Elementary particle, Lambda baryon, 01 natural sciences, Helicity, Baryon, 0103 physical sciences, Nuclear Experiment, 010306 general physics, Nucleon, Lepton
Abstract

Beam helicity asymmetries in the $\overrightarrow{e}p \rightarrow e' K^{+} \Lambda $ reaction have been measured at unprecedentedly low four-momentum transfers $\langle Q^{2} \rangle = 0.05$ (GeV/c)2. At the Mainz Microtron (MAMI), the experiment was performed with a longitudinally polarized beam and an out-of-plane detection of the scattered electron. This experiment probed the associated helicity-dependent structure function ${\rm d} \sigma_{LT'}/{\rm d} \Omega_K^{c.m.}$ , which is sensitive to the details of resonances of the proton. The results were compared to models for kaon electroproduction using effective Lagrangians. The MAMI data is not supporting the Kaon-Maid isobar model, which uses strong longitudinal couplings of the virtual photon to nucleon resonances and predicts a strong peaking of the structure function at forward angles and low $Q^{2}$ . The data is also in disagreement with a Regge-plus-resonance model that predicts the incorrect sign of the structure function. The combination of the MAMI results wih data taken at higher four-momentum transfers measured at Jefferson Lab indicates a smooth transition in $Q^{2}$ without significant changes of the interference pattern in the electroproduction process.

Published
2017

19. Feasibility study for the measurement of πN transition distribution amplitudes at P¯ANDA in p¯p→J/ψπ0

Author

Tristan Weber, Michaela Thiel, T. Wasem, J. Schwiening, M. Kube, R. Schmitz, D. Lehmann, A. Trzcinski, A. Amoroso, A.A. Efremov, Alexander Olshevskiy, R. Klasen, Herbert Koch, M. Maggiora, A. Dbeyssi, Dipanwita Dutta, F. E. Maas, A. Chlopik, E. Etzelmüller, P. Wintz, V. Lucherini, P. Schakel, P. De Remigis, Krzysztof Swientek, G.S. Shabratova, H. Deppe, Angelo Rivetti, Riccardo Introzzi, K. Dutta, P. Wieczorek, V. M. Datar, W. Lauth, E. A. Strokovsky, L. Busso, M. Hoek, F. Balestra, G. Maniscalco, D. Khaneft, R. Schnell, S. Vejdani, N. G. Minaev, V. Chernetsky, B. Seitz, U. Thoma, K. K. Seth, Mario Bragadireanu, Amiran Tomaradze, B. Fröhlich, S. Pflüger, Valentino Rigato, Franco Bradamante, I. A. Kuyanov, E. Gutz, V. M. Abazov, D. P. Watts, Lennart Isaksson, M. Albrecht, V. Arefiev, T. Schröder, B. Singh, G. Sonika, A. Fechtchenko, C. Rosenbaum, L. Schmitt, Bernd Voss, B. Hetz, S. Sanchez, Magnus Wolke, S.A. Zaporozhets, A. Filippi, S. Coli, Bhavin Patel, A. Khoukaz, Markus Ball, A. Pitka, Krisztian Peters, B. Ramstein, K. Khosonthongkee, M. Pfaffinger, Torbjörn Bäck, D. Veretennikov, J. Pütz, R.A. Salmin, P. Balanutsa, B. J. Liu, A. Hayrapetyan, Chinorat Kobdaj, R. W. Novotny, P. Genova, W. Kühn, P. F. Dalpiaz, S. Belostotski, Ulrich Wiedner, A.S. Vodopianov, Yu.N. Rogov, Wojciech Krzemien, M. Wojciechowski, T. Erlen, Giuseppe Giraudo, B. Zwieglinski, H. Smit, E. Prencipe, J. Jaworowski, R.A. Kunne, S. Lusso, A.G. Fedunov, P. Musiol, C. Schnier, Yan Liang, H. Ohm, Paolo Montagna, A. Karavdina, G. Mazza, N. K. Walford, G. Boca, Boris Batyunya, M. Zyzak, V. Varentsov, M. Kuhlmann, M. Zühlsdorf, V. V. Tokmenin, G. Sterzenbach, M. Tiemens, Stanisław Kistryn, A. Kumar, Alessandro Bressan, F. Lisowski, Paul Alois Buhler, V. Carassiti, D. Prasuhn, M. Zambrana, R. Dzhygadlo, J. Lühning, M.K. Suleimanov, O. Noll, P. Salabura, M. Patsyuk, Christian Schmidt, Johann Zmeskal, M. Barnyakov, A. A. Piskun, F. Feldbauer, Susanna Costanza, Zbigniew Rudy, V. E. Blinov, F. De Mori, Alexander D. Vasiliev, V. Metag, C. Sfienti, Utpal Roy, E. Perevalova, M. Cardinali, R. Birsa, R. Teshev, Aleksandra Wrońska, Egle Tomasi-Gustafsson, F. Uhlig, K. Pysz, T. Sefzick, M. Steinen, V.B. Chandratre, M. Krebs, Matthias Richter, J. P. Wessels, W. Schäfer, M. Fritsch, M. Korjik, J. Rieke, Andreas Lehrach, M. Kavatsyuk, A. Kulkarni, R. F. Parodi, R. Karabowicz, A. Sanchez-Lorente, T.A. Pocheptsov, Valery Dormenev, A. Magiera, H. Flemming, Vassili Kachanov, K. Kalita, W. Erni, P. Poznański, T. Holtmann, O. Miklukho, J. Pychy, S. Bleser, Yu. Yu. Lobanov, Zhiqing Liu, T. Quagli, D. Branford, O. Corell, Konstantin Beloborodov, Dirk Grunwald, Jize Zhao, R. Böhm, L. Capozza, L. Ferrero, A. K. Hergemöller, T. Held, Mario Greco, A. Wilms, Alessandro Drago, I. Augustin, Mathias Fink, A. E. Yakutin, N. Belikov, D. I. Glazier, Sergey Nazarenko, D. Kang, A. Boukharov, M. Kesselkaul, V. Abramov, A. N. Skachkova, S. Bukreeva, U. Thöring, Hans-Georg Zaunick, A. Ryazantsev, S. Marcello, C. Guaraldo, V. Pothodi Chackara, K. Makonyi, A.I. Zinchenko, S. Ryzhikov, S. Orfanitski, Edward Lisowski, K. A. Martin, Ajit Kumar Mohanty, L. Lavezzi, Kirill M. Semenov-Tian-Shansky, S.A. Kononov, L. Gruber, Grzegorz Filo, M. Domagala, L. Cao, V. Di Pietro, S. Grieser, B. Ketzer, S. Schlimme, Marten Ole Schmidt, Alberto Rotondi, M. Michel, C. Schwarz, S. I. Manaenkov, E. A. Kravchenko, R. Beck, A. Gillitzer, Krzysztof Korcyl, B. Slowinski, G. Kesik, Felice Iazzi, U. Müller, D. Calvo, B. Krusche, C. Wang, M. Steinke, A. Gerhardt, V. L. Malyshev, I. Marishev, E. Widmann, Gianangelo Bracco, Harald Kleines, N. I. Zhuravlev, A. Lehmann, D. Nicmorus Marinescu, Patrick Achenbach, A. Apostolou, D. Walther, Johann Marton, C. Sowa, T. Saito, R. Dosdall, Ayut Limphirat, A. Belias, Dan Pantea, A. Täschner, A. Mustafa, D. Marchand, P. Kulessa, M. Galuska, C. Ugur, W. Ikegami Andersson, M. Savrie, C. Hammann, J. C. van der Weele, D. Wölbing, G.B. Pontecorvo, Vivekanand Jha, Hasko Stenzel, D. Przyborowski, P. Drexler, Antoni Szczurek, Tord Johansson, A. Gerasimov, T. Triffterer, A. Britting, S. Ahmed, Mihai Caprini, W. Eyrich, A. Kozela, V. Grishin, O. Malyshev, U. Kurilla, Yupeng Yan, H. Sohlbach, S. Leiber, P. Strzempek, X. Y. Shen, V. V. Mochalov, M. I. Martínez, U. Lynen, I. Lehmann, M. Bai, A. A. Zhdanov, M. Preston, M. Urban, M. Mikirtychyants, I. K. Keshk, Andrea Lavagno, Grzegorz Korcyl, H. Ahmadi, J. Biernat, A. Lai, M. Traxler, Richard Wheadon, M. Pelizäus, A. Cotta Ramusino, D. Rodríguez Piñeiro, Markus Büscher, R. Kliemt, M. M. Macri, V. Kormilitsin, A. Yu. Barnyakov, Z. Li, Ivan Kisel, Arpit Parmar, Tomasz Fiutowski, C. Schmidt, C. Morales Morales, J. Płażek, Michael Düren, Z. J. Sun, H. Loehner, M. Pugach, P. Fedorets, K. Suzuki, A. P. Onuchin, E. Fioravanti, Andrea Bianconi, B. Ma, Yu.M. Mel'nik, M. Deiseroth, F. H. Heinsius, D. G. Ireland, J. S. Lange, Anne-Laure Martin, B. Wohlfahrt, H. Xu, J. Van de Wiele, P. N. Deepak, D. A. Morozov, N. Hüsken, Livio Bianchi, Günter Kemmerling, S. Löchner, B. Galnander, Jifeng Hu, N. B. Skachkov, G. D. Alexeev, T. Ullrich, I. Zimmermann, B. J. Roy, E.K. Koshurnikov, D. Steinschaden, M. Michałek, Bruce Yabsley, M. N. Wagner, S. Wronka, Smbat Grigoryan, Paola Gianotti, Andrey V. Izotov, T. Kuske, S. C. Li, A. G. Zorin, A. Davidenko, M. Lindemulder, V. Astakhov, Andreas Herten, V.I. Lobanov, V.Kh. Dodokhov, Oleg V. Missevitch, Y. Wang, C. Hahn, A. Pyszniak, M.G. Sapozhnikov, L. V. Malinina, Andrey Uzunian, Andrei Fedorov, H. Orth, A. Ehret, Alastair J. Wilson, L. V. Nogach, R. Nellen, Hans Calén, I. Garzia, A.F. Makarov, Harphool Kumawat, S. I. Serednyakov, A. Galoyan, Paweł Moskal, Karin Schönning, W. Czyzycki, J. G. Messchendorp, A. Riccardi, M. Kümmel, A. Sokolov, Maria Krawczyk, Ting Xiao, S. Godre, A. G. Denig, Marek Idzik, M. O. Distler, Frank Goldenbaum, P. Srisawad, G. Kozlov, K. Biguenko, P.J.J. Lemmens, S. Spataro, M. Yu. Barabanov, S. Maldaner, A. Zambanini, Ajay Kumar Rai, I. Shein, M. Böhm, M. Rossbach, A. Demekhin, Yury Tikhonov, A. A. Derevschikov, C. Fritzsch, M. Babai, J. S. Díaz, V. K. Rodionov, A. E. Blinov, A. Cebulla, S. Reiter, A. Samartsev, Bartosz Mindur, V. N. Goryachev, H. B. Liu, B. Kopf, E. Atomssa, C. Wendel, Sean A Dobbs, J. Pochodzalla, Yu.I. Davydov, Genady Gavrilov, Andrew Levin, M.P. Bussa, G. Rosner, S. Jasper, Ankhi Roy, J. Olave, A. Bersani, Bo Cederwall, K. Götzen, B. Kamys, P. Wüstner, Piotr Lebiedowicz, D. Bettoni, A. Dolgolenko, P.-E. Tegnér, Mariana Nanova, D. Melnychuk, V. Akishina, P. A. Semenov, V. Balanutsa, P. Mahlberg, H. Leithoff, Victor Bobrovnikov, M. Papenbrock, L. Fava, R. Valente, R. Veenstra, C. Motzko, K.-T. Brinkmann, F. Nerling, V. Uzhinsky, Harald Merkel, M. Destefanis, D. Lin, Y.M. Goncharenko, M. C. Mora Espí, N. Divani Veis, Pawel Marciniewski, Mohammed Al-Turany, Q. Hu, Andrzej Kupsc, M. Steinacher, Tobias Stockmanns, J. Ritman, S. Diehl, V. Serdyuk, Jerzy Smyrski, A. Gromliuk, M. Mignone, M. Moritz, S. Sosio, S. Schadmand, G. Schepers, S. Poslavskiy, and Joachim Pettersson

Subjects
Quantum chromodynamics, Physics, Particle physics, Luminosity (scattering theory), Annihilation, Meson, 010308 nuclear & particles physics, 7. Clean energy, 01 natural sciences, Particle identification, Nuclear physics, Factorization, Antiproton, 0103 physical sciences, High Energy Physics::Experiment, 010306 general physics, Bar (unit)
Abstract

The exclusive charmonium production process in (P) over barp annihilation with an associated pi 0 meson (p) over barp -> J/psi pi(0) is studied in the framework of QCD collinear factorization. The feasibility of measuring this reaction through the J/psi -> e(+) e(-) decay channel with the AntiProton ANnihilation at DArmstadt ((P) over bar ANDA) experiment is investigated. Simulations on signal reconstruction efficiency as well as the background rejection from various sources including the (P) over barp -> pi(+)pi(-)pi(0) and (p) over barp -> J/psi pi(0)pi(0) reactions are performed with PANDAROOT, the simulation and analysis software framework of the (P) over bar ANDA experiment. It is shown that the measurement can be done at (P) over bar ANDA with significant constraining power under the assumption of an integrated luminosity attainable in four to five months of data taking at the maximum design luminosity.

Published
2017

20. Vertical Beam Polarization at MAMI

Author

P. Herrmann, B. S. Schlimme, T. Kolar, Concettina Sfienti, J. Beričič, K. Aulenbacher, L. Correa, Damir Bosnar, A. Tyukin, M. Dehn, M. Hoek, F. E. Maas, M. Mihovilovic, V. Tioukine, Patrick Achenbach, B. Spruck, S. Baunack, D. Bender, F. Schulz, Harald Merkel, H. J. Kreidel, J. Müller, M. O. Distler, U. Müller, F. Nillius, S. Kegel, J. Pochodzalla, S. Štajner, Michaela Thiel, S. Širca, Ivica Friščić, M. Schoth, Y. Kohl, B. Gutheil, H. Fonvieille, A. Weber, A. Nuck, Anselm Esser, Laboratoire de Physique de Clermont (LPC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Clermont Auvergne (UCA)-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique de Clermont ( LPC ), and Institut National de Physique Nucléaire et de Physique des Particules du CNRS ( IN2P3 ) -Université Clermont Auvergne ( UCA ) -Centre National de la Recherche Scientifique ( CNRS )

Subjects
Accelerator Physics (physics.acc-ph), Nuclear and High Energy Physics, Physics - Instrumentation and Detectors, Photon, media_common.quotation_subject, Vertical polarization, [PHYS.PHYS.PHYS-ACC-PH]Physics [physics]/Physics [physics]/Accelerator Physics [physics.acc-ph], FOS: Physical sciences, Electron accelerator, Electron, Mott polarimeter, 01 natural sciences, Asymmetry, law.invention, Optics, Møller polarimeter, law, 0103 physical sciences, Compton polarimeter, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], [ PHYS.PHYS.PHYS-ACC-PH ] Physics [physics]/Physics [physics]/Accelerator Physics [physics.acc-ph], Born approximation, 010306 general physics, Nuclear Experiment, [ PHYS.PHYS.PHYS-INS-DET ] Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], Instrumentation, media_common, Physics, Wien filter, 010308 nuclear & particles physics, business.industry, Particle accelerator, Polarimeter, Instrumentation and Detectors (physics.ins-det), Polarization (waves), Physics - Accelerator Physics, business
Abstract

For the first time a vertically polarized electron beam has been used for physics experiments at MAMI in the energy range between 180 and 855 MeV. The beam-normal single-spin asymmetry $A_{\mathrm{n}}$, which is a direct probe of higher-order photon exchange beyond the first Born approximation, has been measured in the reaction $^{12}\mathrm C(\vec e,e')^{12}\mathrm C$. Vertical polarization orientation was necessary to measure this asymmetry with the existing experimental setup. In this paper we describe the procedure to orient the electron polarization vector vertically, and the concept of determining both its magnitude and orientation with the available setup. A sophisticated method has been developed to overcome the lack of a polarimeter setup sensitive to the vertical polarization component.

Published
2017

21. First measurement of proton's charge form factor at very low $Q^2$ with initial state radiation

Author

Michaela Thiel, M. O. Distler, J. Beričič, M. Mihovilovič, Concettina Sfienti, Jan C. Bernauer, L. Nungesser, S. Širca, Ivica Friščić, A. G. Denig, T. Beranek, D. G. Middleton, J. Pochodzalla, P. Achenbach, R. Böhm, F. Schulz, A. Tyukin, Damir Bosnar, K. A. Griffioen, M. I. Ferretti Bondy, Marc Vanderhaeghen, Y. Kohl, M. Cardinali, M. Rohrbeck, L. Debenjak, M. Schoth, L. Correa, M. Hoek, B. S. Schlimme, M. Weinriefer, U. Müller, S. Sánchez Majos, S. Kegel, S. Štajner, H. Fonvieille, A. Weber, Anselm Esser, J.M. Friedrich, Harald Merkel, Laboratoire de Physique de Clermont (LPC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Clermont Auvergne (UCA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique de Clermont ( LPC ), and Institut National de Physique Nucléaire et de Physique des Particules du CNRS ( IN2P3 ) -Université Clermont Auvergne ( UCA ) -Centre National de la Recherche Scientifique ( CNRS )

Subjects
experimental methods, Proton, elastic scattering, 01 natural sciences, High Energy Physics - Experiment, Lamb shift, High Energy Physics - Experiment (hep-ex), Initial state radiation, Form factor, Radiative corrections, Radiative transfer, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], [ PHYS.NEXP ] Physics [physics]/Nuclear Experiment [nucl-ex], Nuclear Experiment (nucl-ex), Nuclear Experiment, Microtron, Elastic scattering, Physics, Form factor (quantum field theory), beam: current, lcsh:QC1-999, 3. Good health, PRIRODNE ZNANOSTI. Fizika, Nuclear and High Energy Physics, FOS: Physical sciences, Bethe-Heitler, 25.30.Bf, Radiation, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Nuclear physics, electron p: scattering, Mainz Linac, [ PHYS.HEXP ] Physics [physics]/High Energy Physics - Experiment [hep-ex], 12.20.-m, 0103 physical sciences, radiation: initial-state interaction, 010306 general physics, numerical calculations, form factor: charge, 41.60.-m, 010308 nuclear & particles physics, Scattering, p: charge, NATURAL SCIENCES. Physics, microtron, spectrometer, lcsh:Physics, experimental results
Abstract

We report on a new experimental method based on initial-state radiation (ISR) in e-p scattering, in which the radiative tail of the elastic e-p peak contains information on the proton charge form factor ($G_E^p$) at extremely small $Q^2$. The ISR technique was validated in a dedicated experiment using the spectrometers of the A1-Collaboration at the Mainz Microtron (MAMI). This provided first measurements of $G_E^p$ for $0.001\leq Q^2\leq 0.004 (GeV/c)^2$., Comment: 6 pages, 3 figures

Published
2017

22. A short-orbit spectrometer for low-energy pion detection in electroproduction experiments at MAMI

Author

D. Baumann, R. Böhm, M. O. Distler, U. Müller, M. Ding, Ivica Friščić, M. Wendel, Harald Merkel, Th. Walcher, and Damir Bosnar

Subjects
Nuclear and High Energy Physics, Physics - Instrumentation and Detectors, Aperture, Physics::Instrumentation and Detectors, FOS: Physical sciences, Scintillator, Kinetic energy, 01 natural sciences, law.invention, Nuclear physics, Telescope, Pion, law, 0103 physical sciences, Nuclear Experiment (nucl-ex), 010306 general physics, Nuclear Experiment, Instrumentation, Microtron, Physics, low-energy pion detection, Spectrometer, 010308 nuclear & particles physics, Detector, Instrumentation and Detectors (physics.ins-det), 3. Good health, Physics::Accelerator Physics
Abstract

A new Short-Orbit Spectrometer (SOS) has been constructed and installed within the experimental facility of the A1 collaboration at Mainz Microtron (MAMI), with the goal to detect low-energy pions. It is equipped with a Browne-Buechner magnet and a detector system consisting of two helium-ethane based drift chambers and a scintillator telescope made of five layers. The detector system allows detection of pions in the momentum range of 50 - 147 MeV/c, which corresponds to 8.7 - 63 MeV kinetic energy. The spectrometer can be placed at a distance range of 54 - 66 cm from the target center. Two collimators are available for the measurements, one having 1.8 msr aperture and the other having 7 msr aperture. The Short-Orbit Spectrometer has been successfully calibrated and used in coincidence measurements together with the standard magnetic spectrometers of the A1 collaboration., Comment: 10 pages, 14 figures

Published
2017
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23. Measurement of the p(e,e′π+)n reaction close to threshold and at low Q2

Author

D. Baumann, Anselm Esser, Patrick Achenbach, B. S. Schlimme, Th. Walcher, S. Širca, Ivica Friščić, U. Müller, C. Ayerbe Gayoso, Damir Bosnar, Michaela Thiel, M. Mihovilovič, M. Schoth, L. Debenjak, F. Schulz, D. G. Middleton, M. O. Distler, J. Pochodzalla, R. Böhm, A. G. Denig, Harald Merkel, Concettina Sfienti, and M. Ding

Subjects
Particle physics, Nuclear and High Energy Physics, media_common.quotation_subject, Kinematics, Interference (wave propagation), 01 natural sciences, Asymmetry, Nuclear physics, Cross section (physics), Low-energy pions, Pion, 0103 physical sciences, Invariant mass, 010306 general physics, Nuclear Experiment, media_common, Physics, Spectrometer, 010308 nuclear & particles physics, lcsh:QC1-999, NATURAL SCIENCES. Physics, PRIRODNE ZNANOSTI. Fizika, Electroproduction experiments, Transverse plane, Short-orbit spectrometer, lcsh:Physics
Abstract

The cross section of the $p(e,e'\pi^+)n$ reaction has been measured for five kinematic settings at an invariant mass of $W = 1094$ MeV and for a four-momentum transfer of $Q^2 = 0.078$ (GeV/$c$)$^2$. The measurement has been performed at MAMI using a new short-orbit spectrometer (SOS) of the A1 collaboration, intended for detection of low-energy pions. The transverse and longitudinal cross section terms were separated using the Rosenbluth method and the transverse-longitudinal interference term has been determined from the left-right asymmetry. The experimental cross section terms are compared with the calculations of three models: DMT2001, MAID2007 and $\chi$MAID. The results show that we do not yet understand the dynamics of the fundamental pion., Comment: version accepted for publishing

Published
2017

24. Beam-Recoil Polarization Measurement of π0 Electroproduction on the Proton in the Region of the Roper Resonance

Author

J. Müller, U. Müller, L. Correa, S. Kegel, J. Pochodzalla, B. S. Schlimme, Patrick Achenbach, Concettina Sfienti, S. Štajner, Anselm Esser, T. Beranek, M. Mihovilovič, Jan C. Bernauer, L. Tiator, I. Yaron, M. Schoth, R. Böhm, H. Fonvieille, A. Weber, F. Schulz, A. G. Denig, D. Bosnar, M. O. Distler, Y. Kohl, Michaela Thiel, L. Nungesser, S. Širca, Ivica Friščić, J. Beričič, A. Tyukin, J.M. Friedrich, Harald Merkel, Laboratoire de Physique de Clermont (LPC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Clermont Auvergne (UCA)-Centre National de la Recherche Scientifique (CNRS), and Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)

Subjects
Quark, Roper resonance, Meson, pseudoscalar meson: production, [PHYS.PHYS.PHYS-ACC-PH]Physics [physics]/Physics [physics]/Accelerator Physics [physics.acc-ph], Nuclear Theory, General Physics and Astronomy, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Nuclear physics, Recoil, 0103 physical sciences, p: recoil, Invariant mass, electron: beam, Proton emission, numerical calculations, 010306 general physics, Nuclear Experiment, Monte Carlo, hydrogen: target, Physics, polarization, N(1440), 010308 nuclear & particles physics, beam: current, helicity, Amplitude, kinematics, differential cross section, pi0: electroproduction, Beam-Recoil Polarization Measurement, Nucleon
Abstract

The helicity-dependent recoil proton polarizations P_{x}^{'} and P_{z}^{'} as well as the helicity-independent component P_{y} have been measured in the p(e[over →],e^{'}p[over →])π^{0} reaction at four-momentum transfer Q^{2}≃0.1 GeV^{2}, center-of-mass proton emission angle θ_{p}^{*}≃90°, and invariant mass W≃1440 MeV. This first precise measurement of double-polarization observables in the energy domain of the Roper resonance P_{11}(1440) by exploiting recoil polarimetry has allowed for the extraction of its scalar electroexcitation amplitude at an unprecedentedly low value of Q^{2}, establishing a powerful instrument for probing the interplay of quark and meson degrees of freedom in the nucleon.

Published
2017

25. Recent Studies of Hypernuclei Formation with Electron Beams at MAMI

Author

Alicia Sanchez Lorente, O. Borodina, Osamu Hashimoto, Concettina Sfienti, F. Schulz, B. Sören Schlimme, Simon Širca, C. Rappold, L. Debenjak, T. R. Saito, M. Schoth, Michaela Thiel, Hiroki Kanda, Kyo Tsukada, U. Müller, Salvador Sánchez Majos, Josef Pochodzalla, Liguang Tang, Harald Merkel, R. Böhm, Damir Bosnar, Carlos Ayerbe Gayoso, S. Hirose, M. O. Distler, E. Kim, Patrick Achenbach, Joerg Reinhold, Ivica Friščić, Junichiro Kusaka, Toshiyuki Gogami, V. Bozkurt, Sho Nagao, Masashi Kaneta, Anselm Esser, Mar Gómez Rodríguez, Satoshi Nakamura, Y. Fujii, and Amur Margaryan

Subjects
Physics, Particle physics, Spectrometer, Nuclear Theory, Electron, Strangeness, Atomic and Molecular Physics, and Optics, Momentum, Nuclear physics, Hypernuclei, MAMI, KAOS, Mesonic weak decay, Cathode ray, High Energy Physics::Experiment, Monochromatic color, Nuclear Experiment, Spectroscopy, Microtron
Abstract

At the Mainz Microtron MAMI exploratory experiments on the spectroscopy of mesonic weak decays (MWD) of electroproduced Λ-hypernuclei were performed. A unique setup was realized to use the broad momentum-band kaon spectrometer Kaos at zero degree angle with respect to the high-intensity electron beam direction to tag strangeness producing processes. A sample of order 103 MWD from a beryllium target was collected by the coincidence technique with the high-resolution multi-spectrometer facility of the A1 Collaboration. It is conjectured that this sample contains monochromatic two-body decays from stopped hyperfragment decays as well as a wide momentum distribution of quasi-free produced Λ- and Σ-hyperon decays and three-body decays from hyperfragments. Stopped hyperfragments will be identified as monochromatic peaks in the π − momentum spectrum from which their masses can be extracted with a precision of 50 keV/c 2.

Published
2013

26. Overview of the electromagnetic production of strange mesons at MAMI

Author

A. Sanchez Lorente, L. G. Tang, Anselm Esser, B. S. Schlimme, Sho Nagao, C. Rappold, S. Hirose, Concettina Sfienti, O. Borodina, T.R. Saito, M. Schoth, Hiroki Kanda, Osamu Hashimoto, Toshiyuki Gogami, M. Gómez Rodríguez, S. Sánchez Majos, U. Müller, C. Ayerbe Gayoso, V. Bozkurt, L. Debenjak, Ivica Friščić, M. O. Distler, Harald Merkel, Y. Fujii, Amur Margaryan, Michaela Thiel, Josef Pochodzalla, P. Bydžovský, Satoshi Nakamura, E. Kim, Simon Širca, R. Böhm, F. Schulz, Kyo Tsukada, Masashi Kaneta, Patrick Achenbach, Damir Bosnar, and Joerg Reinhold

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Photon, Meson, Hadron, Strangeness, Lambda baryon, Helicity, Sigma baryon, Nuclear physics, strangeness reactions, kaon electro-production, missing mass spectroscopy, structure functions, Nuclear Experiment, Microtron
Abstract

The Mainz Microtron MAMI provides a continuous-wave unpolarized or spin-polarized electron beam with energies up to 1.6 GeV and high degrees of polarization. Electro-production of strange mesons is performed in the multi-spectrometer facility with the Kaos spectrometer for kaon detection and a high-resolution spectrometer for electron detection in plane or out of plane. Differential cross section measurements of exclusive p ( e , e ′ K + ) Λ , Σ 0 reactions at low four-momentum transfers in the nucleonʼs third resonance region have been done, followed by a measurement of the beam helicity asymmetry for p ( e → , e ′ K + ) Λ . These studies are important for the understanding of the effective coupling of photons to the hadrons and their resonances and electromagnetic form factors entering different effective Lagrangian models for photo- and electro-production of strangeness. The polarized structure function, extracted from the beam helicity asymmetry, shows an especially high sensitivity to model parameters.

Published
2013

27. Differential cross section measurement of the 12C(e,e’pp)10Beg.s. reaction

Author

J. Pochodzalla, R. Böhm, C. Ayerbe Gayoso, Carlotta Giusti, U. Müller, Carlo Barbieri, M. O. Distler, A. G. Denig, Patrick Achenbach, Ivica Friščić, Damir Bosnar, Mihael Makek, Th. Walcher, S. Sanches Majos, Jan C. Bernauer, M. Schwamb, B. S. Schlimme, Harald Merkel, and L. Nungesser

Subjects
Nuclear reaction, Physics, Nuclear and High Energy Physics, 010308 nuclear & particles physics, Hadron, Nuclear Theory, Electron scattering, nucleon-nucleon correlations, 12C, 01 natural sciences, Nuclear physics, Cross section (physics), Excited state, 0103 physical sciences, Nuclear cross section, Atomic physics, 010306 general physics, Ground state, Nucleon, Nuclear Experiment, Microtron
Abstract

The differential cross section was measured for the 12C(e, e’pp)10Be g.s. reaction at energy and momentum transfers of 163MeV and 198MeV/c, respectively. The measurement was performed at the Mainz Microtron by using two high-resolution magnetic spectrometers of the A1 Collaboration and a newly developed silicon detector telescope. The overall resolution of the detector system was sufficient to distinguish the ground state from the first excited state in 10Be. We chose a super-parallel geometry that minimizes the effect of two-body currents and emphasizes the effect of nucleon-nucleon correlations. The obtained differential cross section is compared to the theoretical results of the Pavia reaction code in which different processes leading to two-nucleon knockout are accounted for microscopically. The comparison shows a strong sensitivity to nuclear- structure input and the measured cross section is seen to be dominated by the interplay between long- and short-range nucleon-nucleon correlations. Microscopic calculations based on the ab initio self-consistent Green’s function method give a reasonable description of the experimental cross section.

Published
2016

28. Silicon Detector Telescope for proton detection in electron scattering reactions at MAMI

Author

R. Böhm, U. Müller, Ivica Friščić, M. Gómez Rodríguez de la Paz, J. Pochodzalla, Michael Seimetz, A. G. Denig, L. Nungesser, M. O. Distler, M. Weinriefer, S. Sánchez Majos, B. S. Schlimme, C. Ayerbe Gayoso, J.M. Friedrich, M. Potokar, D. Baumann, Damir Bosnar, Luca Doria, Mihael Makek, Th. Walcher, Patrick Achenbach, M. Ding, Simon Širca, Jan C. Bernauer, and Harald Merkel

Subjects
Nuclear and High Energy Physics, Silicon, Physics::Instrumentation and Detectors, chemistry.chemical_element, Scintillator, 01 natural sciences, law.invention, Nuclear physics, Telescope, Optics, law, 0103 physical sciences, silicon detector, digital signal processing, electron scattering, Nuclear Experiment, 010306 general physics, Instrumentation, Microtron, Physics, Range (particle radiation), Spectrometer, 010308 nuclear & particles physics, business.industry, Detector, Solid angle, chemistry, Physics::Accelerator Physics, business
Abstract

A new Silicon Detector Telescope has been constructed and installed within the experimental facility of the A1 collaboration at Mainz Microtron, with the goal to detect low-energy protons. It consists of seven silicon layers for energy and angle measurement and a plastic scintillator for triggering purposes. The detector subtends a solid angle up to 88 msr, depending on the distance from the target and covers the proton kinetic energy range of 25–41 MeV with the mean energy resolution σ E = 0.47 MeV , operating at 500 kHz. Digital signal processing methods applied for energy reconstruction have been important for keeping the acceptable energy resolution at high counting rates. The Silicon Detector Telescope has been successfully used in double and triple coincidence measurements along with the magnetic spectrometers of the A1 collaboration.

Published
2012

29. Strange hadronic physics in electroproduction experiments at the Mainz Microtron

Author

B. S. Schlimme, Sho Nagao, O. Borodina, D. Bosnar, R. Böhm, L. Debenjak, Simon Širca, A. Sanchez Lorente, M. Schoth, V. Bozkurt, Toshiyuki Gogami, Joerg Reinhold, S. Sánchez Majos, M. Gómez Rodríguez, L. G. Tang, C. Ayerbe Gayoso, U. Müller, Eunji Kim, T.R. Saito, P. Bydžovský, Concettina Sfienti, Osamu Hashimoto, P. Achenbach, Anselm Esser, J. Pochodzalla, Michaela Thiel, Y. Fujii, Amur Margaryan, C. Rappold, Ivica Friščić, Satoshi Nakamura, Harald Merkel, M. O. Distler, S. Hirose, F. Schulz, and Kyo Tsukada

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Spectrometer, Nuclear Theory, Hadron, Strangeness reactions, Kaon electroproduction, Missing mass spectroscopy, Hypernuclei, Decay-pion spectroscopy, Strangeness, Nuclear physics, Cross section (physics), Effective lagrangian, Nuclear Experiment, Spectroscopy, Microtron, Beam (structure)
Abstract

Present and future research into the electroproduction of strangeness plays an important role at Mainz Microtron MAMI. With the Kaos spectrometer for kaon detection operated in the multi-spectrometer facility first cross section measurements of the exclusive p ( e , e ′ K + ) Λ , Σ 0 reactions at low-momentum transfers have been performed. These measurements have clearly discriminated between effective Lagrangian models for photo- and electroproduction of strangeness. Recently, the Kaos spectrometer was upgraded to a double-arm spectrometer for the measurement of elementary cross sections at very forward scattering angles and for the missing mass spectroscopy of hypernuclear states. In parallel, pioneering experiments on decay-pion spectroscopy of electroproduced hypernuclei were carried out at MAMI. Future experiments will on the one side address the cross section of the elementary process with polarized beam and on the other side continue the hypernuclear spectroscopy with different light nuclear targets.

Published
2012

30. Decay Pion Spectroscopy of Electro-Produced Hypernuclei

Author

C. Ayerbe Gayoso, L. G. Tang, A. Sanchez Lorente, Anselm Esser, C. Rappold, Osamu Hashimoto, Damir Bosnar, Simon Širca, T.R. Saito, E. Kim, U. Müller, Concettina Sfienti, L. Debenjak, Toshiyuki Gogami, R. Böhm, Kyo Tsukada, Ivica Friščić, Patrick Achenbach, Joerg Reinhold, B. S. Schlimme, Sho Nagao, F. Schulz, M. Schoth, J. Pochodzalla, Mario E. Gómez, Satoshi Nakamura, Y. Fujii, Amur Margaryan, V. Bozkurt, M. O. Distler, Harald Merkel, S. Hirose, and O. Borodina

Subjects
Physics, Particle physics, Meson, Spectrometer, Physics::Instrumentation and Detectors, Nuclear Theory, Strangeness, Hypernucleus, Atomic and Molecular Physics, and Optics, Particle identification, Nuclear physics, Particle decay, Pion, High Energy Physics::Experiment, hypernuclei electroproduction, pion decay, Nuclear Experiment, Spectroscopy
Abstract

The investigation of light hypernuclei is quite important for understanding the basic YN interaction and the mechanism of hypernuclear structure. We started the commissioning of the decay pion spectroscopy of light hypernuclei at MAMI-C in 2011. In order to realize the K+ tagging efficiently, some detectors on KAOS spectrometer were upgraded or newly installed. The existing and well-studied spectrometers, SpekA, SpekC were used as pion spectrometers. The analysis is ongoing to estimate the detectors performance and develop the spectrometers for future experiments with higher beam intensity. The preliminary results of the particle identification are presented in this article.

Published
2012

31. Experimental studies of few-body systems at MAMI

Author

M. O. Distler

Subjects
Physics, Proton, Nuclear Theory, Momentum transfer, Electric form factor, General Physics and Astronomy, Few-body systems, Nuclear physics, Deuterium, General Materials Science, Neutron, Physical and Theoretical Chemistry, Atomic physics, Nuclear Experiment, Microtron, Spin-½
Abstract

Few-body experiments at the Mainz Microtron were focused on a number of selected topics. Double-polarization experiments to determine the neutron electric form factor Gen have been performed using both deuterium and polarized helium-3 targets. The structure of 3He has been studied in the reactions 3H e e(ee,e′n) and 3H e e(ee,e′p) with large (transversal) missing momenta and in quasi-elastic electron scattering. Electromagnetically induced two-nucleon knockout has been investigated in order to study the role of correlated nucleon-nucleon motion in the nucleus. Measurements of the (e,e′pn) reaction on 3He and 16O were performed for the first time. A triple-polarization experiment of type 3H e e(ee,e′ep)d has been performed, where, in addition, the spin of the knocked out proton is analyzed. This measurement provides information on the spin-dependent momentum distribution of proton-deuteron clusters in the 3He nucleus. Hence, by tagging the outgoing deuteron spin-polarized 3He might also serve as an effective polarized proton target for electron scattering experiments. Moreover, in inclusive 3,4He(e,e′) measurements at low momentum transfer, the effect of 3-body-forces has been studied.

Published
2011

32. Strange hadrons – strangeness in strongly interacting particles

Author

R. Böhm, L. Nungesser, U. Müller, M. Weinriefer, M. Potokar, Patrick Achenbach, Jan C. Bernauer, Mihael Makek, M. Gómez Rodríguez, B. S. Schlimme, Th. Walcher, M. O. Distler, Harald Merkel, L. Debenjak, Simon Širca, Damir Bosnar, M. Bösz, C. J. Yoon, T. R. Saito, S. Sánchez Majos, C. Ayerbe Gayoso, P. Jennewein, K. Grießinger, Anselm Esser, J. Pochodzalla, and Ivica Friščić

Subjects
Quark, Physics, Strange quark, Particle physics, Meson, High Energy Physics::Phenomenology, Nuclear Theory, General Physics and Astronomy, Strangeness production, Strangeness, Bottom quark, Nuclear physics, Strange matter, Quark star, Physics::Accelerator Physics, High Energy Physics::Experiment, General Materials Science, Physical and Theoretical Chemistry, Nuclear Experiment
Abstract

In 2007 the Mainz Microtron MAMI has been upgraded to 1.5 GeV electron beam energy, crossing the energy threshold for open strangeness production. The strangeness quantum number, as carried by the strange quark, provides valuable information on the contribution of individual quark flavours to hadronic processes. Theoretically, the strange quark with its rest energy of order 150 MeV is particularly interesting because it can neither be treated as a massless nor as a heavy quark. Experimentally, an instrument of central importance for the charged kaon electro-production off the proton or light nuclei at MAMI is the magnetic spectrometer Kaos that was installed recently and is now routinely operated by the A1 collaboration.

Published
2011

33. Particle tracking in kaon electroproduction with cathode-charge sampling in multi-wire proportional chambers

Author

M. Bösz, L. Nungesser, Harald Merkel, U. Müller, Mihael Makek, Simon Širca, R. Böhm, Anselm Esser, S. Sánchez Majos, C. Ayerbe Gayoso, Damir Bosnar, M. Potokar, M. O. Distler, Patrick Achenbach, L. Debenjak, M. Gómez Rodríguez de la Paz, J. Pochodzalla, Ivica Friščić, B. S. Schlimme, M. Weinriefer, and Jan C. Bernauer

Subjects
Physics, Nuclear and High Energy Physics, Range (particle radiation), Physics - Instrumentation and Detectors, Spectrometer, Physics::Instrumentation and Detectors, FOS: Physical sciences, Charge density, Instrumentation and Detectors (physics.ins-det), Electron, Tracking (particle physics), Charged particle, Particle detector, Nuclear physics, Cathode ray, Nuclear Experiment (nucl-ex), tracking and position-sensitive detectors, multi-wire proporational chambers, Nuclear Experiment, Instrumentation
Abstract

Wire chambers are routinely operated as tracking detectors in magnetic spectrometers at high-intensity continuous electron beams. Especially in experiments studying reactions with small cross-sections the reaction yield is limited by the background rate in the chambers. One way to determine the track of a charged particle through a multi-wire proportional chamber (MWPC) is the measurement of the charge distribution induced on its cathodes. In practical applications of this read-out method, the algorithm to relate the measured charge distribution to the avalanche position is an important factor for the achievable position resolution and for the track reconstruction efficiency. An algorithm was developed for operating two large-sized MWPCs in a strong background environment with multiple-particle tracks. Resulting efficiencies were determined as a function of the electron beam current and on the signal amplitudes. Because of the different energy-losses of pions, kaons, and protons in the momentum range of the spectrometer the efficiencies depend also on the particle species.

Published
2011

34. The RMS charge radius of the proton and Zemach moments

Author

M. O. Distler, Thomas Walcher, and Jan C. Bernauer

Subjects
Physics, Nuclear and High Energy Physics, Nuclear Theory, Proton, Electric form factor, FOS: Physical sciences, Charge density, Radius, Lamb shift, Nuclear Theory (nucl-th), Charge radius, Quantum electrodynamics, Moment (physics), Physics::Atomic Physics, Nuclear Experiment (nucl-ex), Atomic physics, Nuclear Experiment, Exotic atom
Abstract

On the basis of recent precise measurements of the electric form factor of the proton, the Zemach moments, needed as input parameters for the determination of the proton rms radius from the measurement of the Lamb shift in muonic hydrogen, are calculated. It turns out that the new moments give an uncertainty as large as the presently stated error of the recent Lamb shift measurement of Pohl et al.. De Rujula's idea of a large Zemach moment in order to reconcile the five standard deviation discrepancy between the muonic Lamb shift determination and the result of electronic experiments is shown to be in clear contradiction with experiment. Alternative explanations are touched upon., Comment: 6 pages, 4 figures, final version includes discussion of systematic and numerical errors

Published
2011

35. First measurements of Λ and hyperons in elementary electroproduction at MAMI

Author

Ch. Rappold, Harald Merkel, D. Nakajima, Simon Širca, O. Borodina, R. Böhm, M. Potokar, B. Göküzüm, S. Bianchin, U. Müller, M. O. Distler, Jan C. Bernauer, Shigeo Minami, Patrick Achenbach, B. S. Schlimme, Damir Bosnar, J. Pochodzalla, Eunji Kim, V. Bozkurt, B. Özel-Tashenov, M. Weinriefer, H. Fonvieille, Achim Denig, K. Grießinger, Anselm Esser, L. Debenjak, F. E. Maas, Ivica Friščić, L. Nungesser, Mihael Makek, S. Sánchez Majos, C. Ayerbe Gayoso, and T.R. Saito

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Spectrometer, Field (physics), 010308 nuclear & particles physics, Nuclear Theory, Hyperon, Strangeness, 01 natural sciences, Nuclear physics, Momentum, 0103 physical sciences, Mass spectrum, High Energy Physics::Experiment, Nuclear Experiment, 010306 general physics, Spectroscopy
Abstract

Since 2008 the magnetic spectrometer Kaos , dedicated to the detection of charged kaons, is operating at the 1.5 GeV electron beam of MAMI at the Institut fur Kernphysik in Mainz, Germany. The strangeness programme performed in 2008–9 is addressing some important issues in the field of elementary kaon photoelectro-production reactions. The identification of Λ and Σ 0 hyperons in the missing mass spectra from kaon production off a liquid hydrogen target demonstrates the capability of the extended facility to perform strangeness electro-production spectroscopy at low momentum transfers Q 2 0.5 ( GeV / c ) 2 . Systematic uncertainties in the cross-section extraction from the data are discussed.

Published
2010

36. A highly polarized target for the electron beam at MAMI

Author

D. Kiselev, Ernst W. Otten, S. Karpuk, M. O. Distler, Werner Heil, J. Krimmer, and Zahir Salhi

Subjects
Physics, Nuclear and High Energy Physics, business.industry, Polarization (waves), Polarized target, Optical pumping, Nuclear physics, Optics, Metastability, Cathode ray, Neutron, Nuclear Experiment, business, Instrumentation, Microtron, Electron scattering
Abstract

Polarized He 3 from metastability exchange optical pumping (MEOP) is used as an effective polarized neutron target for electron scattering experiments at the MAinz MIcrotron (MAMI). With the present setup an initial polarization of up to 72% has been obtained at the experimental area. A novel calibration technique will be presented which allows the determination of the absolute polarization within a relative uncertainty of 3%.

Published
2009

37. Noise and radiation damage in silicon photomultipliers exposed to electromagnetic and hadronic radiation

Author

B. S. Schlimme, L. Nungesser, R. Böhm, U. Müller, C. J. Yoon, Th. Walcher, M. O. Distler, M. Gomez Rodroiguez De La Paz, Jan C. Bernauer, Patrick Achenbach, M. Weinriefer, S. Sánchez Majos, C. Ayerbe Gayoso, J. Pochodzalla, and Harald Merkel

Subjects
Physics, Nuclear and High Energy Physics, Photomultiplier, Physics::Instrumentation and Detectors, business.industry, Radiation, Particle detector, Optics, Silicon photomultiplier, Electron beam processing, Radiation damage, Nuclear Experiment, business, Instrumentation, Microtron, Noise (radio)
Abstract

For the electron arm tracking system in the KAOS spectrometer at the Mainz Microtron MAMI a detector based on 2 m long scintillating fibres read out by silicon photomultipliers (SiPM) is planned. Because of the detector's close proximity to the intense electron beam a study of noise and radiation damage in SiPM has been performed. A sample of devices was exposed directly to a 14 MeV electron beam and to a mixed radiation field in the experimental area. First noticeable effects are a large increase in the dark count rate and a severe loss of the gain uniformity.

Published
2009

38. Experiments on few-nucleon systems at MAMI

Author

M. O. Distler

Subjects
Physics, Particle physics, Proton, Nuclear Theory, Electric form factor, Order (ring theory), Type (model theory), Atomic and Molecular Physics, and Optics, Nuclear physics, Neutron, Nuclear Experiment, Nucleon, Electron scattering, Spin-½
Abstract

The experimental effort at the Mainz Microtron with respect to few-body physics is focused on a number of selected topics. The structure of 3He has been studied in the reactions \(^3\vec{{\rm H}}{\rm e}(\vec{e},e{\prime}n)\) and \(^3\vec{{\rm H}}{\rm e}(\vec{e},e{\prime}p)\) with large (transversal) missing momenta and in quasi-elastic electron scattering. Experiments to determine the neutron electric form factor Gen have been performed – a measurement at a four-momentum transfer Q2 ∼ 1.5(GeV/c)2 took place in July 2007. Electromagnetically induced two-nucleon knockout has been investigated in order to study the role of correlated nucleon-nucleon motion in the nucleus. Measurements of the (e,e′ pn) reaction on 3He and 16O were performed for the first time. A triple-polarization experiment of type \(^3\vec{{\rm H}}{\rm e}(\vec{e},e{\prime}\vec{p})d\) has been performed in August 2007, where, in addition, the spin of the knocked-out proton is analyzed. This measurement provides information on the spin-dependent momentum distribution of proton-deuteron clusters in the 3He nucleus. By using this deuteron-tagging method spin-polarized 3He might also serve as an effective polarized proton target for electron scattering experiments.

Published
2008

39. Measurement of propagation time dispersion in a scintillator

Author

L. Nungesser, M. Weinriefer, M. O. Distler, R. Böhm, U. Müller, Jan C. Bernauer, J.M. Friedrich, Patrick Achenbach, Th. Walcher, S. Sánchez Majos, C. Ayerbe Gayoso, S. Schlimme, Luca Doria, Harald Merkel, and J. Pochodzalla

Subjects
Physics, Nuclear and High Energy Physics, Propagation time, Photomultiplier, Photon, Physics::Instrumentation and Detectors, business.industry, Monte Carlo method, FOS: Physical sciences, Scintillator, Optics, Path length, Distortion, Dispersion (optics), Nuclear Experiment (nucl-ex), business, Nuclear Experiment, Instrumentation
Abstract

One contribution to the time resolution of a scintillation detector is the signal time spread due to path length variations of the detected photons from a point source. In an experimental study a rectangular scintillator was excited by means of a fast pulsed ultraviolet laser at different positions along its longitudinal axis. Timing measurements with a photomultiplier tube in a detection plane displaced from the scintillator end face showed a correlation between signal time and tube position indicating only a small distortion of photon angles during transmission. The data is in good agreement with a Monte Carlo simulation used to compute the average photon angle with respect to the detection plane and the average propagation time. Limitations on timing performance that arise from propagation time dispersion are expected for long and thin scintillators used in future particle identification systems., Comment: Submitted to Nucl. Instr. and Meth. in Phys. Res. A

Published
2007

40. Determination of quadrupole strengths in the γ∗p→Δ(1232) transition at Q2=0.20(GeV/c)2

Author

J.M. Friedrich, C. Ayerbe Gayoso, D. Baumann, Th. Walcher, M. O. Distler, Luca Doria, D. S. Dale, M. Potokar, M. Ding, M. Weis, L. Nungesser, Harald Merkel, U. Müller, Tancredi Botto, R. Neuhausen, A. Karabarbounis, R. Böhm, Patrick Achenbach, A. Christopoulou, Nikolaos Sparveris, I. Nakagawa, S. Stiliaris, A. Piegsa, Costas N. Papanicolas, Jan C. Bernauer, S. Stave, Damir Bosnar, Michael Seimetz, Aron M. Bernstein, J. Pochodzalla, Simon Širca, and Mihael Makek

Subjects
Nuclear physics, Physics, Nuclear and High Energy Physics, Dipole, Amplitude, Quark model, Hadron, Quadrupole, Coulomb, Constituent quark, High Energy Physics::Experiment, Nuclear Experiment, Microtron
Abstract

We report new precise p ( e → , e ′ p ) π 0 measurements at the peak of the Δ + ( 1232 ) resonance at Q 2 = 0.20 ( GeV / c ) 2 performed at the Mainz Microtron (MAMI). The new data are sensitive to both the electric (E2) and the Coulomb (C2) quadrupole amplitudes of the γ ∗ N → Δ transition. They yield precise quadrupole to dipole amplitude ratios: CMR = ( − 5.09 ± 0.28 stat + sys ± 0.30 model ) % and EMR = ( − 1.96 ± 0.68 stat + sys ± 0.41 model ) % for M 1 + 3 / 2 = ( 39.57 ± 0.75 stat + sys ± 0.40 model ) ( 10 −3 / m π + ) . The new results are in disagreement with Constituent Quark Model predictions and in qualitative agreement with models that account for mesonic contributions, including recent Lattice calculations. They thus give further credence to the conjecture of deformation in hadronic systems favoring the attribution of the origin of deformation to the dominance of mesonic effects.

Published
2007

41. High-Resolution Decay-Pion Spectroscopy of $_\Lambda ^4\text{H}$ Hypernuclei

Author

Y. Fujii, Amur Margaryan, Lin-Ya Tang, Manami Fujita, L. Correa, U. Müller, Masashi Kaneta, Simon Širca, B. S. Schlimme, C. Sfienti, P. Achenbach, S. Aulenbacher, Sho Nagao, M. Mihovilovic, M. Steinen, W. Kusaka, R. Böhm, Ivica Friščić, F. Schulz, J. Beričič, M. Schoth, Hiroki Kanda, Michaela Thiel, A. Tyukin, Toshiyuki Gogami, Kyo Tsukada, H. Fonvieille, A. Weber, S. N. Nakamura, M. O. Distler, Y. Takahashi, Anselm Esser, Harald Merkel, D. Bosnar, S. Bleser, S. Kegel, J. Pochodzalla, A. Sanchez Lorente, Y. Kohl, Laboratoire de Physique de Clermont (LPC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Clermont Auvergne (UCA)-Centre National de la Recherche Scientifique (CNRS), and Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)

Subjects
Lambda: hypernucleus, Binding energy, Nuclear Theory, momentum spectrum, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Lambda, 01 natural sciences, tagged beam, Nuclear physics, Mainz Linac, Pion, 0103 physical sciences, Lambda: binding energy, Nuclear emulsion, 010306 general physics, Spectroscopy, Nuclear Experiment, Microtron, spectrometer calibration, Physics, Spectrometer, bias and uncertainty in peak fitting, 010308 nuclear & particles physics, Resolution (electron density), pi: decay, magnetic spectrometer, hypernuclear mass spectroscopy, microtron, mesonic weak decay, nuclear emulsion
Abstract

International audience; The first observation of \({}_{\Lambda }^{4}\text{H}\) fragments by means of decay-pion spectroscopy with a high resolution magnetic spectrometer was achieved in 2012 at the Mainz Microtron MAMI. The extracted Λ binding energy was consistent with older nuclear emulsion data, but almost one order of magnitude higher in precision, while being limited by systematic uncertainties. This paper gives details on the kaon tagging at 0° forward angle which was indispensable for the success of the experiment. In addition, a re-analysis of the data collected in 2012 is presented, including an improved a posteriori spectrometer calibration and a more robust fitting of the decay-pion peak in the momentum spectrum.

Published
2015

42. Observation ofHΛ4Hyperhydrogen by Decay-Pion Spectroscopy in Electron Scattering

Author

Concettina Sfienti, K. Yoshida, Patrick Achenbach, S. Sánchez Majos, Ivica Friščić, C. Ayerbe Gayoso, Osamu Hashimoto, Masashi Kaneta, C. Rappold, M. Mihovilovic, T. R. Saito, D. Bosnar, Michaela Thiel, M. Schoth, F. Schulz, L. Debenjak, Hiroki Kanda, U. Müller, S. N. Nakamura, Junichiro Kusaka, Kyo Tsukada, M. O. Distler, A. Sanchez Lorente, Y. Kohl, Simon Širca, L. G. Tang, E. Kim, Y. Fujii, Amur Margaryan, R. Böhm, B. S. Schlimme, V. Bozkurt, Sho Nagao, Harald Merkel, Toshiyuki Gogami, S. Hirose, Joerg Reinhold, A. Weber, O. Borodina, Anselm Esser, and J. Pochodzalla

Subjects
Physics, Particle physics, Spectrometer, Nuclear Theory, General Physics and Astronomy, chemistry.chemical_element, Hypernucleus, Nuclear physics, Pion, chemistry, High Energy Physics::Experiment, Beryllium, Nuclear Experiment, Spectroscopy, Microtron, Electron scattering
Abstract

At the Mainz Microtron MAMI, the first high-resolution pion spectroscopy from decays of strange systems was performed by electron scattering off a ^9B

Published
2015

43. Experimental investigations of the hypernucleus $_Λ^4$H

Author

Patrick Achenbach, F. Schulz, Ivica Friščić, Masashi Kaneta, A. Sanchez Lorente, Kyo Tsukada, D. Bosnar, R. Böhm, Y. Fujii, Y. Kohl, Amur Margaryan, S. Bleser, L. G. Tang, Michaela Thiel, Simon Širca, M. Schoth, Hiroki Kanda, M. Steinen, Concettina Sfienti, W. Kusaka, M. Mihovilovic, J. Beričič, S. Aulenbacher, L. Correa, U. Müller, Manami Fujita, B. S. Schlimme, Sho Nagao, Toshiyuki Gogami, S. N. Nakamura, M. O. Distler, S. Kegel, J. Pochodzalla, Anselm Esser, Y. Takahashi, Harald Merkel, H. Fonvieille, A. Weber, A. Tyukin, Laboratoire de Physique de Clermont (LPC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Clermont Auvergne (UCA)-Centre National de la Recherche Scientifique (CNRS), A1, Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique Corpusculaire - Clermont-Ferrand (LPC), and Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Lambda: hypernucleus, QC1-999, Nuclear Theory, Astrophysics, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, tagged beam, Particle identification, pi, 010305 fluids & plasmas, Nuclear physics, Momentum, Mainz Linac, Pion, Coincident, beryllium: target, 0103 physical sciences, Calibration, 010306 general physics, Nuclear Experiment, Microtron, Physics, Spectrometer, pi: decay, resolution, suppression, Hypernucleus, magnetic spectrometer, microtron, hydrogen, momentum: calibration, background: random, High Energy Physics::Experiment, luminosity: high, particle identification
Abstract

International audience; Negatively charged pions from two-body decays of stopped _Lambda^4H hypernuclei were studied in 2012 at the Mainz Microtron MAMI, Germany. The momenta of the decay-pions were measured with unprecedented precision by using high-resolution magnetic spectrometers. A challenge of the experiment was the tagging of kaons from associated K^+∧ production off a Be target at very forward angles. In the year 2014, this experiment was continued with a better control of the systematic uncertainties, with better suppression of coincident and random background, improved particle identification, and with higher luminosities. Another key point of the progress was the improvement in the absolute momentum calibration of the magnetic spectrometers.

Published
2015

44. Observation of (_Λ^4)H Hyperhydrogen by Decay-Pion Spectroscopy in Electron Scattering

Author

A, Esser, S, Nagao, F, Schulz, P, Achenbach, C, Ayerbe Gayoso, R, Böhm, O, Borodina, D, Bosnar, V, Bozkurt, L, Debenjak, M O, Distler, I, Friščić, Y, Fujii, T, Gogami, O, Hashimoto, S, Hirose, H, Kanda, M, Kaneta, E, Kim, Y, Kohl, J, Kusaka, A, Margaryan, H, Merkel, M, Mihovilovič, U, Müller, S N, Nakamura, J, Pochodzalla, C, Rappold, J, Reinhold, T R, Saito, A, Sanchez Lorente, S, Sánchez Majos, B S, Schlimme, M, Schoth, C, Sfienti, S, Širca, L, Tang, M, Thiel, K, Tsukada, A, Weber, and K, Yoshida

Subjects
Nuclear Theory, Electron Scattering, Hypernuclei, MAMI, KAOS, Decay-Pion Spectroscopy, High Energy Physics::Experiment, Nuclear Experiment
Abstract

At the Mainz Microtron MAMI, the first high-resolution pion spectroscopy from decays of strange systems was performed by electron scattering off a (^9)Be target in order to study the Λ binding energy of light hypernuclei. Positively charged kaons were detected by a short-orbit spectrometer with a broad momentum acceptance at 0° forward angles with respect to the beam, efficiently tagging the production of strangeness in the target nucleus. Coincidentally, negatively charged decay pions were detected by two independent high-resolution spectrometers. About 10^3 pionic weak decays of hyperfragments and hyperons were observed. The pion momentum distribution shows a monochromatic peak at p_π ≈ 133 MeV/c, corresponding to the unique signature for the two-body decay of hyperhydrogen (_Λ^4)H→(^4)H+π^-, stopped inside the target. Its Λ binding energy was determined to be B_Λ = 2.12 ± 0.01 (stat) ± 0.09 (syst) MeV with respect to the (^3)H + Λ mass.

Published
2015

45. Measurement of the beam-recoil polarization in low-energy virtual Compton scattering from the proton

Author

S. Sánchez Majos, J.M. Friedrich, C. Ayerbe Gayoso, J. Beričič, J. Pochodzalla, R. Van de Vyver, A. Van Overloop, L. Nungesser, M. Benali, Simon Širca, Damir Bosnar, D. Baumann, X. Defaÿ, H. Fonvieille, Thomas Walcher, Luca Doria, Barbara Pasquini, L. Correa, M. Potokar, R. Böhm, O. Postavaru, G. Laveissière, I. K. Bensafa, P. Janssens, M. Mihovilovic, J. Marroncle, B. S. Schlimme, P. Achenbach, M. Weinriefer, M. O. Distler, G. Tamas, Harald Merkel, Michael Seimetz, L. Van Hoorebeke, U. Müller, Mihael Makek, M. Ding, N. d'Hose, Dirk Ryckbosch, and Jan C. Bernauer

Subjects
Nuclear and High Energy Physics, FORM-FACTORS, FOS: Physical sciences, MAMI, High Energy Physics - Experiment, Nuclear physics, 3-SPECTROMETER SETUP, High Energy Physics - Experiment (hep-ex), Recoil, Nuclear Experiment (nucl-ex), Nuclear Experiment, NUCLEON, Microtron, Physics, Spectrometer, Compton scattering, Polarimeter, Polarization (waves), NATURAL SCIENCES. Physics, PRIRODNE ZNANOSTI. Fizika, Physics and Astronomy, POLARIMETER, GENERALIZED POLARIZABILITIES, Cathode ray, High Energy Physics::Experiment, Nucleon
Abstract

Double-polarization observables in the reaction (e) over right arrow ep -> e'(p) over right arrow'gamma have been measured at Q(2) = 0.33 (GeV/c)(2). The experiment was performed at the spectrometer setup of the A1 Collaboration using the 855 MeV polarized electron beam provided by the Mainz Microtron (MAMI) and a recoil proton polarimeter. From the double-polarization observables the structure function P-LT(perpendicular to) is extracted for the first time, with the value (-15.4 +/- 3.3((stat.)-2.4) (+1.5) (syst.)) GeV-2, using the low-energy theorem for virtual Compton scattering. This structure function provides a hitherto unmeasured linear combination of the generalized polarizabilities of the proton.

Published
2015

46. 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

47. Monte Carlo simulation of virtual Compton scattering below pion threshold

Author

Ch. Hyde-Wright, Marc Vanderhaeghen, J.M. Friedrich, D. Marchand, P.Y. Bertin, N. Degrande, Harald Merkel, David Lhuillier, R. Van de Vyver, R. Di Salvo, J. Roche, P. Janssens, M. O. Distler, G. Tamas, J. Van de Wiele, I. K. Bensafa, H. Fonvieille, Luca Doria, S. Kerhoas, N. d'Hose, Th. Walcher, L. Van Hoorebeke, S. Jaminion, G. Laveissière, Laboratoire de Physique Corpusculaire - Clermont-Ferrand (LPC), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Département d'Astrophysique, de physique des Particules, de physique Nucléaire et de l'Instrumentation Associée (DAPNIA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institut de Physique Nucléaire d'Orsay (IPNO), 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), VCS, and 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)

Subjects
Physics, Nuclear and High Energy Physics, Photon, 010308 nuclear & particles physics, Monte Carlo method, Compton scattering, Solid angle, Probability and statistics, 01 natural sciences, High Energy Physics - Experiment, Nuclear physics, Pion, Physics - Data Analysis, Statistics and Probability, [PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph], 0103 physical sciences, Nuclear Experiment, 010306 general physics, Instrumentation, [PHYS.PHYS.PHYS-DATA-AN]Physics [physics]/Physics [physics]/Data Analysis, Statistics and Probability [physics.data-an]
Abstract

This paper describes the Monte Carlo simulation developed specifically for the VCS experiments below pion threshold that have been performed at MAMI and JLab. This simulation generates events according to the (Bethe-Heitler + Born) cross section behaviour and takes into account all relevant resolution-deteriorating effects. It determines the `effective' solid angle for the various experimental settings which are used for the precise determination of photon electroproduction absolute cross section., Comment: 24 pages, 6 figures, to be published in Nuclear Instruments and Methods in Physics Research, A One author added

Published
2006

48. Final State Interaction Effects in 3He(e ,e'p)

Author

Ernst-Wilhelm Otten, R. Skibiński, Werner Heil, P. Merle, Michael Seimetz, Ingo Sick, Hiroyuki Kamada, Simon Širca, R. Böhm, M. Weis, Ch. Normand, M. Kohl, A. Nogga, J. Bermuth, M. Potokar, Th. Walcher, H. Schmieden, W. Glöckle, M. Hauger, J.M. Friedrich, Jörg Schmiedeskamp, R. Neuhausen, M. O. Distler, Harald Merkel, J. Jourdan, Jacek Golak, Glen A. Warren, H. Wöhrle, A. Klein, D. Baumann, M. Zeier, M. Ding, Daniela Rohe, P. Bartsch, Th. Pospischil, C. Carasco, D. Bosnar, K. W. Krygier, G. Testa, U. Müller, Henryk Witała, and P. Jennewein

Subjects
Physics, Nuclear and High Energy Physics, Current (mathematics), 3He-structure, 010308 nuclear & particles physics, Operator (physics), Continuum (design consultancy), Momentum transfer, Kinematics, State (functional analysis), 01 natural sciences, Exact solutions in general relativity, Quantum mechanics, Quantum electrodynamics, 0103 physical sciences, Final-state interaction, Polarized electron scattering, 010306 general physics, Ground state
Abstract

Asymmetries in quasi-elastic 3 He ( e → , e ′ p ) have been measured at a momentum transfer of 0.67 (GeV/ c ) 2 and are compared to a calculation which takes into account relativistic kinematics in the final state and a relativistic one-body current operator. With an exact solution of the Faddeev equation for the 3 He -ground state and an approximate treatment of final state interactions in the continuum good agreement is found with the experimental data.

Published
2003

49. Performance of a compact detector package for the out-of-plane spectrometer system

Author

Nilanga Liyanage, Ricardo Alarcon, S. Dolfini, J. R. Comfort, S. Kowalski, J. Zhao, Shalev Gilad, C. Vellidis, S. Sobczynski, K. Joo, P. Bourgeois, K. A. Dow, J. Kirkpatrick, R. S. Hicks, T. McIlvain, A. Dooley, Costas N. Papanicolas, D. S. Dale, S. Georgakopoulos, C. Mertz, C. Tschalaer, S. B. Soong, I. Nakagawa, Jian-Ping Chen, E. Six, R. A. Miskimen, M. Farkhondeh, D. J. Margaziotis, J. R. Calarco, G. A. Peterson, W. Turchinetz, C. Kunz, Nikolaos Sparveris, M. O. Distler, D. R. Tieger, N. I. Kaloskamis, A. Hotta, Glen A. Warren, D. Jordan, J. Shaw, A. J. Sarty, Ross Milner, S. Stiliaris, F. Casagrande, T. Zwart, Tancredi Botto, M. Pavan, Aron M. Bernstein, Z.-L. Zhou, Joseph B. Mandeville, S. E. Williamson, Tadaaki Tamae, X. Jiang, M. Holtrop, S. Širca, W. Boeglin, Larry Weinstein, William Bertozzi, G. Tsentalovich, A. F. Ramirez, G. W. Dodson, Yutaro Sato, S. Stave, A. Karabarbounis, R. Beck, M. B. Epstein, A. Young, and D. Rowntree

Subjects
Physics, Nuclear physics, Nuclear and High Energy Physics, Pion, Spectrometer, Detector, Compton scattering, Electron, Nuclear Experiment, Instrumentation, Electron scattering, Linear particle accelerator, Particle identification
Abstract

We report on the design and performance of compact detector packages currently installed in the four magnetic out-of-plane spectrometers for electron scattering experiments at the MIT-Bates Linear Accelerator Center. The detector packages have been designed to meet the mechanical requirements arising from out-of-plane particle detection. They offer good trajectory and momentum reconstruction, particle identification and time-of-flight measurements for electrons, pions, protons, and deuterons with large momentum bites and in broad kinematical ranges and high luminosities. The detectors have so far been used with great success in out-of-plane measurements of 12 C ( e → , e ′ p ) , 2 H ( e → , e ′ p ) , virtual Compton scattering below pion threshold and in studies of the N → Δ transition in both exclusive reaction channels 1 H ( e → , e ′ p ) π 0 and 1 H ( e → , e ′ π + )n .

Published
2002

50. The horizontal drift chambers for the focal plane proton-polarimeter of the 3-spectrometer setup at MAMI

Author

A. Kozlov, Glen A. Warren, P. Bartsch, J. Sanner, D. Baumann, M. Ding, Ronald Ransome, G. Rosner, K. W. Krygier, Michael Seimetz, Ingo Sick, S. Grözinger, Klemen Bohinc, M. Kahrau, Achim Richter, M. Weis, D. Elsner, O. Strähle, R. Geiges, Justin I. McIntyre, R. Neuhausen, F. Klein, N. Clawiter, U. Müller, I. Ewald, X. Q. Wu, P. König, S. Derber, Th. Walcher, A. Wagner, J.M. Friedrich, M. Hamdorf, P. Jennewein, R. Böhm, S. Hedicke, Th. Pospischil, S. Malov, A. Süle, P. Merle, M. Potokar, E. A. J. M. Offermann, A. Liesenfeld, H. Schmieden, Harald Merkel, J. Jourdan, H. Kramer, J. Lac, and M. O. Distler

Subjects
Physics, Nuclear and High Energy Physics, Argon, Proton, Spectrometer, Physics::Instrumentation and Detectors, business.industry, chemistry.chemical_element, Polarimeter, Cardinal point, Optics, chemistry, business, Instrumentation, Image resolution
Abstract

Large-area horizontal drift chambers have been built for use in a proton polarimeter. A gas mixture of 20% argon and 80% ethane is used. The left–right assignment is achieved by measuring the difference of the signals induced on neighboring potential wires. A spatial resolution of 300 μm is achieved.

Published
2002

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