Search

Your search keyword '"Ch, Schmidt"' showing total 205 results
Start Over Author "Ch, Schmidt"
205 results on '"Ch, Schmidt"'

1. Measurement of double polarisation asymmetries in ω-photoproduction

Author

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

Subjects
Meson production, Polarisation in interactions and scattering, Light mesons (SCB0), Physics, QC1-999
Abstract

The first measurements of the beam-target-helicity-asymmetries E and G in the photoproduction of ω-mesons off protons at the CBELSA/TAPS experiment are reported. E (G) was measured using circularly (linearly) polarised photons and a longitudinally polarised target. E was measured over the photon energy range from close to threshold (Eγ=1108 MeV) to Eγ=2300 MeV and G at a single energy interval of 1108

Published
2015
Full Text
View/download PDF

2. The polarization observables T, P, and H and their impact on γp→pπ0 multipoles

Author

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

Subjects
Baryon spectroscopy, Meson photoproduction, Polarization observables, Multipoles, Physics, QC1-999
Abstract

Data on the polarization observables T, P, and H for the reaction γp→pπ0 are reported. Compared to earlier data from other experiments, our data are more precise and extend the covered range in energy and angle substantially. The results were extracted from azimuthal asymmetries measured using a transversely polarized target and linearly polarized photons. The data were taken at the Bonn electron stretcher accelerator ELSA with the CBELSA/TAPS detector. Within the Bonn-Gatchina partial wave analysis, the new polarization data lead to a significant narrowing of the error band for the multipoles for neutral-pion photoproduction.

Published
2015
Full Text
View/download PDF

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

Author

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

Subjects
Physics, QC1-999
Abstract

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

Published
2015
Full Text
View/download PDF

4. Experimental constraints on the ω–nucleus real potential

Author

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

Subjects
Physics, QC1-999
Abstract

In a search for ω mesic states, the production of ω-mesons in coincidence with forward going protons has been studied in photon induced reactions on 12C for incident photon energies of 1250–3100 MeV. The π0γ pairs from decays of bound or quasi-free ω-mesons have been measured with the CBELSA/TAPS detector system in coincidence with protons registered in the MiniTAPS forward array. Structures in the total energy distribution of the π0γ pairs, which would indicate the population and decay of bound ω 11B states, are not observed. The π0γ cross section of 0.3 nb MeV−1 sr−1 observed in the bound state energy regime between −100 and 0 MeV may be accounted for by yield leaking into the bound state regime because of the large in-medium width of the ω-meson. A comparison of the measured total energy distribution with calculations suggests the real part V0 of the ω 11B potential to be small and only weakly attractive with V0(ρ=ρ0)=−15±35(stat)±20(syst) MeV in contrast to some theoretical predictions of attractive potentials with a depth of 100–150 MeV.

Published
2014
Full Text
View/download PDF

5. Observation of a structure in the $$M_{p\eta }$$ invariant mass distribution near 1700 $$\hbox {MeV}/\hbox {c}^2$$ in the $$\gamma \mathbf {p \rightarrow p \pi ^0 \eta } $$ reaction

Author

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

Subjects
Nuclear and High Energy Physics
Published
2021

6. An optimization of protocol for mixed chimerism induction in mice model.

Author

B Machaliński, M Walczak, Ch Schmidt, V Dziedziejko, M Hałasa, E Pius, K Grymuła, and M Baśkiewicz-Masiuk

Subjects
Cytology, QH573-671
Abstract

Studies on mixed chimerism are currently focused primarily on obtaining less toxic conditioning protocols. With these issues in mind, we have undertaken the attempt to optimize the procedure of mixed chimerism induction in mice. In order to reduce toxicity, we used decreasing doses of total body irradiation (TBI) together with combination of blocking antibodies. We also tried to eliminate immunosuppression (cyclophosphamide - CP) treatment after bone marrow transplantation. B6.SJL-PtprcaPep3b mice were injected with 20-30 x 106 bone marrow cells from Balb C mice. Mice were treated with TBI (3 - 1.5 - 0 Gy) on "-1" day of the experiment and blocking antibodies against CD40L ("0", and "4" days) and additionally anti-CD8 ("-2" day) and/or anti-NK1.1 ("-3" day). Mice in certain groups also received CP (175 mg/kg) on "2" day. Presence of mixed chimerism was assessed in peripheral blood cells by flow cytometry on the 1st, 2nd, 3rd, 4th, 6th and 8th weeks of the experiment by detecting of CD45.1 (characteristic for B6.SJL-PtprcaPep3b strain) and CD45.2 (characteristic for Balb C strain) antigens expression. We also analyzed the percentage of peripheral blood CD8 T-cells (CD3e/CD8a) and NK cells (Ly-49D/NK1.1). We found that reduction of TBI dose and elimination of CP decrease the rate of mixed chimerism formation. The highest percentage of donor cells was obtained in the group of animals treated with 3 Gy of TBI, CP and combination of anti-CD40L, anti-CD8, and anti-NK1.1 antibodies. The 3 Gy TBI was necessary to induce stable mixed chimerism, but it could be obtained without the CP use. The percentage of CD3e/CD8a and Ly-49D/NK1.1 cells was significantly lower in the groups of mice treated by corresponding antibodies. Moreover, we observed the lowest number of peripheral blood Ly-49D/NK1.1 cells in the group of animals with highest mixed chimerism. Our experiments in mice model can help in better understanding of mixed chimerism phenomenon and in selecting the method of mixed chimerism induction with lowest possible toxicity. This also might improve the protocols of stable mixed chimerism induction in humans, and in the future, the effectiveness of vascularized organ transplantation.

Published
2010
Full Text
View/download PDF

7. 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

8. 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

9. 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

10. Measurement of the helicity asymmetry E for the reaction $$ \gamma p\rightarrow \pi ^0 p$$

Author

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

Subjects
Nuclear physics, Physics, Nuclear and High Energy Physics, Photon, media_common.quotation_subject, Hadron, Bremsstrahlung, Nuclear fusion, Electron, Photon energy, Helicity, Asymmetry, media_common
Abstract

A measurement of the double-polarization observable E for the reaction $$\gamma p\rightarrow \pi ^0 p$$ γ p → π 0 p is reported. The data were taken with the CBELSA/TAPS experiment at the ELSA facility in Bonn using the Bonn frozen-spin butanol (C$$_4$$ 4 H$$_9$$ 9 OH) target, which provided longitudinally-polarized protons. Circularly-polarized photons were produced via bremsstrahlung of longitudinally-polarized electrons. The data cover the photon energy range from $$E_\gamma =600$$ E γ = 600 to 2310 MeV and nearly the complete angular range. The results are compared to and have been included in recent partial wave analyses.

Published
2021

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

Author

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

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

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

Published
2020

12. Measurement of the helicity asymmetry

Author

M, Gottschall, F, Afzal, A V, Anisovich, D, Bayadilov, R, Beck, M, Bichow, K Th, Brinkmann, V, Crede, M, Dieterle, F, Dietz, H, Dutz, H, Eberhardt, D, Elsner, R, Ewald, K, Fornet-Ponse, St, Friedrich, F, Frommberger, A, Gridnev, M, Grüner, E, Gutz, Ch, Hammann, J, Hannappel, J, Hartmann, W, Hillert, Ph, Hoffmeister, Ch, Honisch, T, Jude, S, Kammer, H, Kalinowsky, I, Keshelashvili, P, Klassen, F, Klein, E, Klempt, K, Koop, B, Krusche, M, Kube, M, Lang, I, Lopatin, P, Mahlberg, K, Makonyi, V, Metag, W, Meyer, J, Müller, J, Müllers, M, Nanova, V, Nikonov, R, Novotny, D, Piontek, G, Reicherz, T, Rostomyan, A, Sarantsev, Ch, Schmidt, H, Schmieden, T, Seifen, V, Sokhoyan, K, Spieker, A, Thiel, U, Thoma, M, Urban, H van, Pee, D, Walther, Ch, Wendel, D, Werthmüller, U, Wiedner, A, Wilson, A, Winnebeck, L, Witthauer, and Y, Wunderlich

Subjects
Regular Article – Experimental Physics
Abstract

A measurement of the double-polarization observable E for the reaction \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\gamma p\rightarrow \pi ^0 p$$\end{document}γp→π0p is reported. The data were taken with the CBELSA/TAPS experiment at the ELSA facility in Bonn using the Bonn frozen-spin butanol (C\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$_4$$\end{document}4H\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$_9$$\end{document}9OH) target, which provided longitudinally-polarized protons. Circularly-polarized photons were produced via bremsstrahlung of longitudinally-polarized electrons. The data cover the photon energy range from \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$E_\gamma =600$$\end{document}Eγ=600 to 2310 MeV and nearly the complete angular range. The results are compared to and have been included in recent partial wave analyses.

Published
2019

14. Hegelianismus und Saint-Simonismus

Author

Hans Ch. Schmidt am Busch, Ludwig Siep, Hans U. Thamer, Norbert Waszek, Hans Ch. Schmidt am Busch, Ludwig Siep, Hans U. Thamer, and Norbert Waszek

Published
2020

15. Universal Scaling Properties of QCD Close to the Chiral Limit

Author

Anirban Lahiri, Frithjof Karsch, Olaf Kaczmarek, and Ch. Schmidt

Subjects
Quark, Physics, Quantum chromodynamics, Particle physics, Strange quark, Nuclear Theory, High Energy Physics::Lattice, High Energy Physics - Lattice (hep-lat), High Energy Physics::Phenomenology, FOS: Physical sciences, General Physics and Astronomy, Order (ring theory), Lattice QCD, Nuclear Theory (nucl-th), Massless particle, High Energy Physics - Phenomenology, High Energy Physics - Lattice, High Energy Physics - Phenomenology (hep-ph), Pion, Continuum (set theory), Nuclear Experiment
Abstract

We present a lattice QCD based determination of the chiral phase transition temperature in QCD with two massless (up and down) and one strange quark having its physical mass. We propose and calculate two novel estimators for the chiral transition temperature for several values of the light quark masses, corresponding to Goldstone pion masses in the range of $58~{\rm MeV}\lesssim m_\pi\lesssim 163~{\rm MeV}$. The chiral phase transition temperature is determined by extrapolating to vanishing pion mass using universal scaling relations. After thermodynamic, continuum and chiral extrapolations we find the chiral phase transition temperature $T_c^0=132^{+3}_{-6}$ MeV. We also show some preliminary calculations that use the conventional estimator for the pseudo-critical temperature and compare with the new estimators for $T_c^0$. Furthermore, we show results for the ratio of the chiral order parameter and its susceptibility and argue that this ratio can be used to differentiate between $O(N)$ and $Z_2$ universality classes in a non-parametric manner., Comment: 10 pages, 6 figures, contribution to the proceeding of workshop on Criticality in QCD and the Hadron Resonance Gas; 29-31 July 2020, Wroclaw, Poland

Published
2021

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

Author

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

Subjects
Physics, Nuclear physics, Nuclear and High Energy Physics, Photon, Meson, 010308 nuclear & particles physics, 0103 physical sciences, Polarization observables, Solid angle, 010306 general physics, Branching (polymer chemistry), Nucleon, 01 natural sciences
Abstract

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

Published
2020

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

Author

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

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

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

Published
2018

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

Author

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

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

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

Published
2018

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

Author

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

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

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

Published
2018

20. Measurement of double polarisation asymmetries in ω -photoproduction

Author

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

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

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

Published
2015
Full Text
View/download PDF

21. The polarization observables T , P , and H and their impact onγp→pπ0multipoles

Author

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

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

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

Published
2015

22. Data onIsandIcinγ→p→pπ0π0reveal cascade decays ofN(1900)viaN(1520)π

Author

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

Subjects
Baryon, Physics, Nuclear physics, Nuclear and High Energy Physics, Pion, Photon, Linear polarization, Partial wave analysis, Photon polarization, Pi, Dalitz plot
Abstract

Photoproduction of two neutral pions off the proton is studied using linearly polarized photons, and the polarization observables I-s and I-c are measured for the first time. These two observables are unique to multi-meson final states; they characterize correlations between the linear photon polarization and the direction of outgoing single particles in photoproduction of three-body final states. The I-s and I-c distributions suggest that, in the 1.8 to 2.0 GeV mass region, the N(1520) 3/2(-)pi intermediate state is reached with reaction dynamics consistent with a dominant J(P) = 3/2(+) wave. These data are included in the Bonn-Gatchina (BnGa) partial wave analysis which is based on a large variety of data; the analysis confirms a significant contribution from the reaction chain gamma p -> N(1900)3/2(+) -> N(1520)3/2(-)pi(0) -> p pi(0)pi(0). (C) 2015 The Authors. Published by Elsevier B.V.

Published
2015

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

Author

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

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

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

Published
2017
Full Text
View/download PDF

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

Author

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

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

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

Published
2014

25. Experimental constraints on the ω–nucleus real potential

Author

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

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

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

Published
2014
Full Text
View/download PDF

26. Determination of the eta '-nucleus optical potential

Author

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

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

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

Published
2013

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

Author

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

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

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

Published
2016

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

Author

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

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

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

Published
2016
Full Text
View/download PDF

29. Application of lock-in thermography for failure analysis in integrated circuits using quantitative phase shift analysis

Author

Frank Altmann, Otwin Breitenstein, Ch. Schmidt, and Publica

Subjects
Materials science, Analytical chemistry, Integrated circuit, Signal, integrated circuit design, law.invention, System in package, Optics, law, Emissivity, Microelectronics, General Materials Science, integrated circuit packaging, Image resolution, Resistive touchscreen, infrared imaging, nondestructive testing, business.industry, Mechanical Engineering, Condensed Matter Physics, integrated circuit testing, lock-in thermography, Mechanics of Materials, Thermography, business, image resolution
Abstract

Lock-in thermography (LIT), which is a well established technique for non-destructive evaluation, can also be used to identify and locate thermal active electrically defects like shorts and resistive opens in microelectronic devices. Defect localization on the level of the integrated circuits (IC) requires a mu m resolution. But LIT can also be applied to locate buried thermal active defects within fully packaged microelectronic devices by analysing the thermal signal detected at the surface of the device. In addition to the lateral localization of the hot spot, its depth can also be determined by analysing the phase shift of the thermal signal. This is especially valued for non destructive defect localization in complex 3D integrated system in package devices (3D Sip). In comparison to competitive thermal imaging techniques, like liquid crystal imaging or fluorescent micro thermal imaging, LIT is easier to apply since it does not need any foreign thermal sensitive layer at the surface of the device. Also, the sensitivity limit of this technique within mu K range is significantly better. In addition the dynamic character of LIT reduces thermal blurring, and the problem of inhomogeneous IR emissivity can be overcome by using the phase image or the 0 degrees-90 degrees image. The spatial resolution limit of the used microscopic thermal imaging setup performed in the mid-wavelength range is about 5 mu m, but can be improved to 1.5 mu m by applying solid immersion lenses. Within the paper, the principle theory of LIT and the practical use for both, single and multiple IC devices is presented.

Published
2012

30. Anomaly in the KS0Σ+ photoproduction cross section off the proton at the K⁎ threshold

Author

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

Subjects
Physics, Nuclear physics, Baryon, Nuclear and High Energy Physics, Cross section (physics), Proton, Meson, Hadron, Elementary particle, Strangeness, Nucleon
Abstract

The γ + p → K 0 + Σ + photoproduction reaction is investigated in the energy region from threshold to E γ = 2250 MeV . The differential cross section exhibits increasing forward-peaking with energy, but only up to the K ⁎ threshold. Beyond, it suddenly returns to a flat distribution with the forward cross section dropping by a factor of four. In the total cross section a pronounced structure is observed between the K ⁎ Λ and K ⁎ Σ thresholds.

Published
2012

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

Author

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

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

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

Published
2012

32. Erratum to: High-statistics study of the reaction $\gamma p\rightarrow p2\pi^{0}$

Author

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

Subjects
Physics, Baryon, Nuclear and High Energy Physics, Meson, Isospin, Partial wave analysis, Bremsstrahlung, Dalitz plot, Photon energy, Atomic physics, Nucleon
Abstract

The photoproduction of 2π$^{0}$ mesons off protons was studied with the Crystal Barrel/TAPS experiment at the electron accelerator ELSA in Bonn. The energy of photons produced in a radiator was tagged in the energy range from 600 MeV to 2.5 GeV. Differential and total cross sections and pπ$^{0}$ π$^{0}$ Dalitz plots are presented. Part of the data was taken with a diamond radiator producing linearly polarized photons, and beam asymmetries were derived. Properties of nucleon and Δ resonances contributing to the pπ$^{0}$ π$^{0}$ final state were determined within the Bonn-Gatchina (BnGa) partial-wave analysis. The data presented here allow us to determine branching ratios of nucleon and Δ resonances for their decays into pπ$^{0}$ π$^{0}$ via several intermediate states. Most prominent are decays proceeding via Δ(1232)π, N(1440)1/2$^{+}$ π, N(1520)3/2$^{−}$ π, N(1680)5/2$^{+}$ π, but also pf$_{0}$(500), pf$_{0}$(980), and pf$_{2}$(1270) contribute to the reaction.

Published
2015

33. The response of different plant life forms to natural environment changes

Author

S. V. Schmidt and Ch. Schmidt

Subjects
Cultural Studies, norm, History, stress, photosynthesis, Sociology and Political Science, Geography, Planning and Development, lcsh:Regional economics. Space in economics, General Economics, Econometrics and Finance, oxygen, Social Sciences (miscellaneous), bioindication, lcsh:HT388
Abstract

This paper contains test results revealing norm and stress reactions of various life-form plants: trees — Betula pendula Roth, Tilia platyphyllos Scop., Pinus sylvetris L; water-plant -Galium palustre L.; grass — Solidago Canadensis; cereal — Secale cereal L. Collection and processing of the material was made in the area of Berlin/Brandenburg, Germany. Clark sensor-based method made it possible to determine the amount and rate of the oxygen evolution by plants in the dark and light phase. Under the reaction norm the average amount of the oxygen evolved and the average rate of metabolism processes during dark and light phases are changing simultaneously. Parabolic and periodic dependences of these changes during the vegetation period has been found. Under the stress reaction (drought, illness) the rate of metabolism dark reactions is increased by 2—3 times as compared with light reactions. The obtained results may be use for bioindication of the climate change in the Baltic Region.

Published
2011

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

Author

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

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

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

Published
2010

35. Biliary Reconstruction Using a Side-to-Side Choledochocholedochostomy With or Without T-Tube in Deceased Donor Liver Transplantation

Author

Guido Schumacher, Andreas Pascher, Peter Neuhaus, Johann Pratschke, Gero Puhl, Sven-Ch Schmidt, Frank Ulrich, Martin Stockmann, Ulf P. Neumann, Olaf Guckelberger, and Sascha Weiss

Subjects
Male, medicine.medical_specialty, Randomization, medicine.medical_treatment, Liver transplantation, Anastomosis, Gastroenterology, law.invention, Lesion, Postoperative Complications, Randomized controlled trial, law, Internal medicine, medicine, Humans, business.industry, Bile duct, Anastomosis, Surgical, Graft Survival, Middle Aged, medicine.disease, Liver Transplantation, Surgery, medicine.anatomical_structure, Biliary tract, Choledochostomy, Drainage, Pancreatitis, Female, medicine.symptom, business
Abstract

Objective: The biliary anastomosis is still one of the major causes for morbidity after orthotopic liver transplantation. The optimal method of reconstruction remains controversial. The aim of the study was to assess biliary complications after liver transplantation using a choledochocholedochostomy with or without a temporary T-tube. Background Data: Several reports have suggested that biliary reconstruction without T-tube is a safer method with a lower rate of biliary complications compared with T-tube insertion. Methods: A total of 194 recipients of deceased donor liver grafts were randomized. In group 1 the biliary reconstruction was performed by side-to-side choledochocholedochostomy with (n = 99) and in group 2 (n = 95) without a T-tube. The T-tube was removed after 6 weeks. Results: The overall biliary complication rate was significantly increased in group 2 (P < 0.0005). Biliary leaks occurred in 5 patients in group 1 and in 9 patients in group 2 (5.05% vs. 9.47%; P = 0.2756 ns). Anastomotic strictures of the bile duct were seen in 7 patients in group 1 and in 8 patients in group 2 (7.07% vs. 8.42%; P = 0.7923 ns). Two of the patients in group 1 and 5 patients in group 2 developed an ischemic type biliary lesion (2.02% vs. 5.26%; P = 0.2716 ns). The rate of reoperations was comparable in both groups. The rate of invasive interventions was higher in the group without T-tubes (9% vs. 18%, P = ns), as was the rate of cholangitis (5% vs. 11%. P = ns) and pancreatitis (4% vs. 14%, P = 0.0218). No complications after removal of the T-tube were observed. Conclusion: This study is a large prospective randomized trial to assess biliary complications that occur following liver transplantation, after anatomizing the bile duct with or without T-tubes. A significant increased rate of complications in the group without T-tube insertion was observed. In summary, our results indicate that the usage of T-tubes is safe and an excellent tool for the quality control of biliary anastomoses.

Published
2009

36. Das Verhalten der 3-Phasenszintigraphie bei Hüftgelenksprothesen

Author

Ch. Schmidt and H. Born

Subjects
medicine.medical_specialty, Bone morphology, medicine.diagnostic_test, business.industry, medicine.medical_treatment, chemistry.chemical_element, Technetium, Scintigraphy, Prosthesis, Leukocyte scintigraphy, chemistry, Orthopedic surgery, medicine, Orthopedics and Sports Medicine, Surgery, Aseptic processing, Nuclear medicine, business, Technetium-99m
Abstract

With the results of about 600 hip joint prostheses examined by scintigraphy, it is evident that nuclear medicine is more than a supplementary examination, especially in the case of a non-cemented isoelastic prosthesis. The combination of 3-phase scintigraphy with leukocyte scintigraphy could solve the problems of infected and aseptic displaced prostheses in 90% of the cases. The conventional X-ray diagnostic being the only method to demonstrate bone morphology is still the primary examination.

Published
2008

37. Knochenmarktransplantation bei Panmyelopathie und akuter Leukämie: Resultate des Westdeutschen Tumorzentrums Essen

Author

G. Linzenmeier, Reinhard Becher, E. Kuwert, M. Bamberg, S. Öhl, Otto Wetter, E. Scherer, G. Schmitt, E. Haralambie, H. J. Richter, L. D. Leder, D. Hantschke, D.K. Hossfeld, Ulrich W. Schaefer, U. Bormann, U. Rüther, M. R. Nowrousian, Ch. Schmidt, W. Luboldt, E. Hierholzer, K. Henneberg, F. Schüning, J.-H. Beyer, and Hans Grosse-Wilde

Subjects
Pregnancy, Pediatrics, medicine.medical_specialty, Autologous marrow, Bone marrow transplantation, business.industry, Anemia, General Medicine, Disease, medicine.disease, Transplantation, Leukemia, hemic and lymphatic diseases, Remission phase, medicine, business
Abstract

Twenty-six bone marrow transplantations were performed at the West Germany Tumour Centre at Essen between December 1975 and December 1981. Three patients had aplastic anaemia, 23 acute leukaemia. Of the leukaemia patients 13 had a recurrence and ten were in full remission at the time of the transplantation. Two of the patients with a recurrence received deep-frozen autologous marrow from the remission phase. One patient with aplastic anaemia had an identical twin as donour, while all other patients received allogeneic marrow from histocompatible family members. Eleven patients are still alive, all three of those with aplastic anaemia, one of those with leukaemia in a recurrence, and seven of those with acute leukaemia in full remission. Two of the survivors have a chronic graft-host reaction, but the others are symptom-free, after an observation period of up to four years. Main causes of death were leukemic recurrence (6), infection (5), and graft-host reaction (2). It would seem that at present bone marrow transplantation offers the best chance of a cure for severe aplastic anaemic and acute leukaemia in adults, but only if transplantation is undertaken early and not in the end-stage of the disease.

Published
2008

38. Chemotherapeutische Behandlungsmöglichkeiten bei fortgeschrittenen Sarkomen

Author

Ch. Schmidt, M. Higi, W. Bierbaum, N. Firusian, Norbert Niederle, M. E. Scheulen, Seeber S, and K. Bremer

Subjects
Oncology, Cisplatin, medicine.medical_specialty, Vincristine, Chemotherapy, Ifosfamide, business.industry, medicine.medical_treatment, Soft tissue, General Medicine, medicine.disease, Radiation therapy, Internal medicine, medicine, Doxorubicin, Sarcoma, business, medicine.drug
Abstract

43 patients with metastasizing sarcomas were treated with a combination of either vincristin, adriamycin and cis-platinum (n = 21) or ifosfamide and cis-platinum at three weeks' intervals in each case. Ten patients responded to the first combination and nine to the second combination with objective tumor regression. Particularly the latter result is remarkable since 16 of the 22 patients had already been pretreated with combinations containing adriamycin. Obviously the combination of ifosfamide and cis-platinum is a promising alternative in metastasizing sarcomas of the bones and soft tissue, especially if the CYVADIC combination--which is often regarded as standard treatment--remained unsuccessful. This has no bearing on additional surgical measures or on radiotherapy which may be necessary in some patients.

Published
2008

39. Kombinierte Chemo- und Radiotherapie bei inoperablem kleinzellig-anaplastischem Bronchialkarzinom: Verlaufsanalyse bei 50 Patienten* 1

Author

M. E. Scheulen, E. Scherer, H. Holfeld, P. Swosdyk, G. Schmitt, Ch. Schmidt, Seeber S, and R. B. Schilcher

Subjects
Oncology, medicine.medical_specialty, Chemotherapy, Vincristine, Cyclophosphamide, business.industry, medicine.medical_treatment, Mediastinum, General Medicine, Asymptomatic, Radiation therapy, medicine.anatomical_structure, Maintenance therapy, Internal medicine, medicine, Radiology, medicine.symptom, Prophylactic cranial irradiation, business, medicine.drug
Abstract

Combined treatment with adriamycin, cyclophosphamide and vincristine (ACO) was used in 50 out-patients with histologically verified small-cell bronchial carcinoma. In 26 patients with locally and regionally limited metastases ("limited disease") radiotherapy (3000 rad focal dose) to mediastinum, hili and tumour opacity as well as prophylactic cranial irradiation (3000 rad focal dose) were performed after 3 cycles of chemotherapy. Complete clinical remission (without endoscopic control) was achieved in 32 out of 50 patients. Remissions in patients with bilateral pulmonary or extrathoracic metastases ("extensive disease", n = 24, 12 complete remissions) only led to limited asymptomatic prolongations of life (median survival time 10 months, median remission period 5 months) despite maintenance therapy. On the other hand patients with "limited disease" had considerable life prolongation (median survival 21 months, historical control value 3--4 months). Seven out of 26 patients in this group survived for 30 months after the onset of the disease, 6 out of 26 are now in their third year after starting therapy without signs of tumour recurrence. The results show that early recognition of patients with local and regional metastases has considerable prognostic value.

Published
2008

40. Kardiale Nebenwirkungen von 5-Fluorouracil

Author

Norbert Niederle, U B. Wandl, Reinhard Becher, Ch. Schmidt, and D. May

Subjects
Cardiotoxicity, medicine.medical_specialty, Chemotherapy, medicine.diagnostic_test, Heart malformation, Sinus tachycardia, business.industry, Colorectal cancer, medicine.medical_treatment, General Medicine, medicine.disease, Fluorouracil, T wave, Internal medicine, medicine, Cardiology, cardiovascular diseases, medicine.symptom, business, Electrocardiography, medicine.drug
Abstract

In four patients (a 54-year-old man and three women aged 57, 60 and 65 years, respectively) with colorectal carcinoma and no obvious cardiac abnormality anginal symptoms and ECG changes occurred during chemotherapy with 5-fluorouracil at a dose of 400 and 600 mg/m2. The ECG changes consisted of descending ST depressions with preterminally negative T waves, terminally negative T waves, ventricular extrasystoles and sinus tachycardia with intermittent atrial fibrillation. The signs first appeared between the second and fourth day of treatment; in two patients they improved with glyceryl trinitrate. A few days after 5-fluorouracil had last been administered all ECG changes had disappeared. The causes of cardiotoxicity of the drug remain unknown.

Published
2008

41. α2-Interferon: erste Behandlungsergebnisse bei der chronischen myeloischen Leukämie

Author

D. W. Beelen, Reinhard Becher, O. Kloke, C. Doberauer, Ch. Schmidt, and Norbert Niederle

Subjects
medicine.medical_specialty, Blast Crisis, business.industry, Initial dose, Myeloid leukemia, General Medicine, Treatment results, Gastroenterology, chemistry.chemical_compound, chemistry, Interferon, Lactate dehydrogenase, Internal medicine, Medicine, Alpha-2 adrenergic receptor, Platelet, business, medicine.drug
Abstract

Interferon (IFN-alpha 2 B) was administered to 21 patients with chronic myeloid leukaemia (CML), at an initial dose of 4 X 10(6) IU/m2 daily subcutaneously, adapted to changes in leukocyte count in the course of treatment. Of 16 patients that could be fully evaluated (12 males, 4 females; aged 21-64 years), 15 were in the chronic phase, one had a blast crisis. "Haematological remission" was achieved in nine of the 16 patients, while in the remainder, with one exception, transitory reduction in leukocyte count was obtained. With pretreatment counts of 18-151 X 10(9)/l, normalization to 2.7-6.9 X 10(9)/l was achieved in 13 patients after 3-40 weeks. In parallel to these effects there was a decrease in platelet count (before treatment 86-1550 X 10(9)/l to 30-279 X 10(9)/l after an average of six weeks) and in lactate dehydrogenase (initially 220-958 U/l to 87-232 U/l after 3-33 weeks). A reduction in Philadelphia chromosome-positive metaphases by as much as 50% was observed in four of eight patients. Administration of IFN-alpha 2 B achieved a relatively rapid cell reduction in the chronic phase of CML. The long-term effect on the course of the disease and the place of IFN in the overall concept of CML treatment remains unanswered.

Published
2008

42. Knochenmarktransplantationen bei Panmyelopathie und Leukämien: unter besonderer Berücksichtigung gnotobiotischer Maßnahmen

Author

E. Kuwert, F. Schüning, K. Henneberg, Hossam K. Mahmoud, M. Bamberg, E. Scherer, O. Wetter, S. Öhl, U. Quast, Ulrich W. Schaefer, Hans Grosse-Wilde, W. Alberti, D. Hantschke, G. Linzenmeier, L. D. Leder, E. Haralambie, Ch. Schmidt, W. Luboldt, M. R. Nowrousian, Reinhard Becher, H. J. Richter, and G. Schmitt

Subjects
medicine.medical_specialty, business.industry, Incidence (epidemiology), First remission, General Medicine, Chronic myeloid leukaemia, Gastroenterology, Transplantation, hemic and lymphatic diseases, Internal medicine, medicine, PANMYELOPATHY, Interstitial pneumonia, Myeloid leukaemia, business, Cause of death
Abstract

Bone-marrow transplantations were performed in 71 patients, 11 with panmyelopathy, 17 with recurrence of acute leukaemia, 25 with acute leukaemia and remission, 18 with chronic myeloid leukaemia. The transplantation was allogenic in 67, autologous in 2, isologous in 2. Eight patients each survived in the panmyelopathy and chronic myeloid leukaemia groups. In the group of patients with acute leukaemia only one patient of those in a recurrence survived the transplantation for several years, but after 6 years there was another recurrence. Of the 20 patients with acute myeloid leukaemia who received the transplantation during their first remission, 11 are still alive. Retransplantation because of the recurrence was employed in one case each of acute and chronic myeloid leukaemia. Main cause of death was interstitial pneumonia with an overall risk of 23%. Only 5% of patients developed severe acute graft-versus-host reaction, grades III-IV. The low incidence of this reaction is possibly due to the strict gnotobiotic measures which in most of the patients led to decontamination of the intestinal tract.

Published
2008

43. Chemotherapie der fortgeschrittenen Lymphogranulomatose: Ergebnisse der MOPP/COPP-Behandlung am Westdeutschen Tumorzentrum Essen

Author

Klaus Höffken, A. Ippisch, Seeber S, Reinhard Becher, Ch. Schmidt, and R. Pfeiffer

Subjects
Chemotherapy, medicine.medical_specialty, Vincristine, Cyclophosphamide, business.industry, medicine.medical_treatment, General Medicine, Procarbazine, Gastroenterology, COPP, Nitrogen mustard, chemistry.chemical_compound, chemistry, Prednisone, Internal medicine, medicine, business, Survival rate, medicine.drug
Abstract

Between 1968 and 1979, a total of 271 patients with advanced Hodgkin's disease received as first systemic chemotherapy MOPP (mechlorethamine [nitrogen mustard], oncovin [vincristine], procarbazine and prednisone) or COPP (as above, but cyclophosphamide instead of nitrogen mustard). In 162 of the 271 patients (60%) full remission was achieved. Demonstration of systemic signs, bioptically confirmed bone-marrow infiltration and suboptimal cytostatic dosage correlated significantly with a lower full-remission rate. A significant trend towards a lower remission rate was demonstrated for stage IV disease, in patients with lymphocyte-poor or unclassified Hodgkin's disease and in those older than 30 years. A five-year recurrence-free period was achieved in 75.5% of patients: stage of the disease and bone-marrow infiltration had a clear influence on recurrence-free survival rate. The results show that 50% of patients with advanced Hodgkin's disease can be cured by chemotherapy.

Published
2008

44. Die gastroösophageale Refluxkrankheit

Author

Ch. Schmidt and B Baumeister

Subjects
medicine.medical_specialty, Text mining, business.industry, Internal medicine, medicine, Reflux, General Medicine, Disease, business, Gastroenterology
Published
2008

45. N∗ and Δ∗ decays into Nπ0π0

Author

D. Menze, Yu. A. Beloglazov, A. V. Sarantsev, Eberhard Klempt, H. Kalinowsky, I. Fabry, V. V. Sumachev, T. Szczepanek, D. Walther, V. A. Nikonov, M. Fuchs, S. Hoeffgen, O. Bartholomy, A. Foesel, A. V. Anisovich, I. Horn, V. Crede, J. Lotz, J. Langheinrich, M. Konrad, H. Flemming, H. van Pee, C. Funke, H. Koch, R. W. Gothe, M. Ostrick, B. Kopf, H. Matthaey, Gisela Anton, U. Thoma, D. V. Novinski, R. Bantes, J. Ernst, Ch. Schmidt, J. Junkersfeld, H. Loehner, B. Krusche, B. Schoch, I. V. Lopatin, H. Schmieden, R. Beck, J. Hoessl, A. B. Gridnev, G. Suft, C.-H. Weinheimer, E. Gutz, A. Ehmanns, and Frank Klein

Subjects
Baryon, Physics, Nuclear and High Energy Physics, Pion, Proton, Hadron spectroscopy, Partial wave analysis, Quark model, Pi, Resonance, High Energy Physics::Experiment, Atomic physics
Abstract

Decays of baryon resonances in the second and the third resonance region into N pi(0)pi(0) are studied by photoproduction of two neutral pions off protons. Partial decay widths of N* and Delta* resonances decaying into Delta(1232)pi, N(pi pi)(S), N(1440)P-11 pi, and N(1520)D-13 pi are determined in a partial wave analysis of this data and of data from other reactions. Several partial decay widths were not known before. Interesting decay patterns are observed which are not even qualitatively reproduced by quark model calculations. In the second resonance region, decays into Delta(1232)pi dominate clearly. The N(pi pi)(S)-wave provides a significant contribution to the cross section, especially in the third resonance region. The P-13(1720) properties found here are at clear variance to PDG values. (c) 2007 Elsevier B.V. All rights reserved.

Published
2008

46. The inclusions of Mg–B (MgB12?) as potential pinning centres in high-pressure–high-temperature-synthesized or sintered magnesium diboride

Author

Tobias Habisreuther, Tatiana Prikhna, Wolfgang Gawalek, Ya. M. Savchuk, P.A. Nagorny, Doris Litzkendorf, Ch. Schmidt, Vladimir S. Melnikov, U. Dittrich, Viktor Moshchil, M. Wendt, Nina Sergienko, V. B. Sverdun, and Jan Dellith

Subjects
Materials science, Metals and Alloys, Analytical chemistry, Atmospheric temperature range, Condensed Matter Physics, Microstructure, Grain size, chemistry.chemical_compound, chemistry, High pressure, Materials Chemistry, Ceramics and Composites, Magnesium diboride, Critical current, Electrical and Electronic Engineering, Current density, Stoichiometry
Abstract

A systematic study of the structure and superconductive characteristics of high-pressure?high-temperature (2?GPa, 700?1000??C)-synthesized and sintered MgB2 without additions from different initial powders was performed. Among various secondary phases Mg?B inclusions with a stoichiometry close to MgB12 were identified. With an increasing amount of these inclusions the critical current density increased. So these inclusions can be feasible pinning centres in MgB2. The highest jc values in zero field were 1300?kA?cm?2 at 10?K, 780?kA?cm?2 at 20?K and 62?kA?cm?2 at 35?K and in 1?T field were 1200?kA?cm?2 at 10?K, 515?kA?cm?2 at 20?K and 0.1?kA?cm?2 at 35?K for high-pressure-synthesized magnesium diboride and the field of irreversibility at 20?K reached 8?T. The average grain sizes calculated from x-ray examinations in materials having high jc were 15?37?nm.

Published
2007

47. High-statistics study of the reaction γp → p2π0

Author

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

Subjects
Nuclear physics, Physics, Nuclear and High Energy Physics, Range (particle radiation), Photon, Meson, law, Linear polarization, Partial wave analysis, Particle accelerator, Nucleon, Beam (structure), law.invention
Abstract

The photoproduction of 2$\pi^0$ mesons off protons was studied with the Crystal Barrel/TAPS experiment at the electron accelerator ELSA in Bonn. The energy of photons produced in a radiator was tagged in the energy range from 600\,MeV to 2.5\,GeV. Differential and total cross sections and $p\pi^0\pi^0$ Dalitz plots are presented. Part of the data was taken with a diamond radiator producing linearly polarized photons, and beam asymmetries were derived. Properties of nucleon and $\Delta$ resonances contributing to the $p\pi^0\pi^0$ final state were determined within the BnGa partial wave analysis. The data presented here allow us to determine branching ratios of nucleon and $\Delta$ resonances for their decays into $p\pi^0\pi^0$ via several intermediate states. Most prominent are decays proceeding via $\Delta(1232)\pi$, $N(1440)1/2^+\pi$, $N(1520)3/2^-\pi$, $N(1680)5/2^+\pi$, but also $pf_0(500)$, $pf_0(980)$, and $pf_2(1270)$ contribute to the reaction.

Published
2015

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

Author

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

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

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

Published
2015

49. Photoproduction of omega mesons off protons and neutrons

Author

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

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

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

Published
2015

50. D7.3 - Mechanical energy converter study for lotic water sensor applications

Author

Ch. Schmidt, Olfa Kanoun, Ch. Schöberlein, T. Keutel, and T. J: Schröder

Subjects
Materials science, business.industry, Environmental monitoring, Electronic engineering, Electrical engineering, Energy transformation, Wireless, Node (circuits), Instrumentation (computer programming), business, Mechanical energy, Energy (signal processing), Power (physics)
Abstract

Wireless sensor systems can help to improve or to expand instrumentation for environmental monitoring systems. For a autonomous power supply of such sensors, a mechanical converter solution will be proposed to convert energy using natural turbulences ever-present in lotic water. This contribution focusses (a) on the mechanical-to-electrical energy conversion using a piezoelectric bimorph and (b) on a suitable DC-DC converter supplying the wireless node built around the commercially available LTC3331 by Linear Technologies.

Published
2015

Catalog

Books, media, physical & digital resources
See catalog results