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1. Differential cross sections for neutron-proton scattering in the region of the <math><mrow><msup><mi>d</mi><mo>*</mo></msup><mrow><mo>(</mo><mn>2380</mn><mo>)</mo></mrow></mrow></math> dibaryon resonance

Author: Adlarson, Patrik, Augustyniak, W., Bardan, W., Bashkanov, M., Bergmann, F. S., Berlowski, M., Bhatt, H., Buescher, M., Calén, Hans, Ciepal, I, Clement, H., Coderre, D., Czerwinski, E., Demmich, K., Doroshkevich, E., Engels, R., Erven, A., Erven, W., Eyrich, W., Fedorets, P., Foehl, K., Fransson, K., Goldenbaum, F., Goslawski, P., Goswami, A., Grigoryev, K., Gullström, C-O, Hauenstein, F., Heijkenskjöld, L., Hejny, V, Hodana, M., Höistad, B., Huesken, N., Jany, A., Jany, B. R., Johansson, T., Kamys, B., Kemmerling, G., Khan, F. A., Khoukaz, A., Kirillov, D. A., Kistryn, S., Kleines, H., Klos, B., Krapp, M., Krzemien, W., Kulessa, P., Kupsc, Andrzej, Lalwani, K., Lersch, D., Lorentz, B., Magiera, A., Maier, R., Marciniewski, Pawel, Marianski, B., Mikirtychiants, M., Morsch, H-P, Moskal, P., Ohm, H., Ozerianska, I, del Rio, E. Perez, Piskunov, N. M., Podkopal, P., Prasuhn, D., Pricking, A., Pszczel, D., Pysz, K., Pyszniak, A., Redmer, C. F., Ritman, J., Roy, A., Rudy, Z., Sawant, S., Schadmand, S., Sefzick, T., Serdyuk, V, Siudak, R., Skorodko, T., Skurzok, M., Smyrski, J., Sopov, V, Stassen, R., Stepaniak, J., Stephan, E., Sterzenbach, G., Stockhorst, H., Stroeher, H., Szczurek, A., Taeschner, A., Trzcinski, A., Varma, R., Wolke, Magnus, Wronska, A., Wuestner, P., Wurm, P., Yamamoto, A., Yurev, L., Zabierowski, J., Zielinski, M. J., Zink, A., Zlomanczuk, Jozef, Zupranski, P., Zurek, M., Workman, R. L., Briscoe, W. J., Strakovsky, I. I., and Svarc, A.
Subjects: Subatomär fysik, Subatomic Physics, ddc:530, dibaryon resonance, Nuclear Experiment, neutron-proton scattering
Abstract: Differential cross sections have been extracted from exclusive and kinematically complete high-statistics measurements of quasifree polarized n⃗p scattering performed in the energy region of the d*(2380) dibaryon resonance covering the range of beam energies Tn=0.98−1.29 GeV (s=2.32−2.44 GeV). The experiment was carried out with the WASA-at-COSY setup having a polarized deuteron beam impinged on the hydrogen pellet target and utilizing the quasifree process dp→np+pspectator. In this way the np differential cross section σ(Θ) was measured over a large angular range. The obtained angular distributions complement the corresponding analyzing power Ay(Θ) measurements published previously. A SAID partial-wave analysis incorporating the new data strengthens the finding of a resonance pole in the coupled D33−G33 waves.
Published: 2020
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2. Differential cross sections for neutron-proton scattering in the region of the d∗(2380) dibaryon resonance

Author: Adlarson, P., Augustyniak, W., Clement, H., WASA-at-COSY Collaboration, Workman, R. L., Briscoe, W. J., Strakovsky, I. I., SAID Data Analysis Center, Švarc, A., Coderre, D., Czerwiński, E., Demmich, K., Doroshkevich, E., Engels, R., Erven, A., Erven, W., Eyrich, W., Fedorets, P., Bardan, W., Föhl, K., Fransson, K., Goldenbaum, F., Goslawski, P., Goswami, A., Grigoryev, Kirill, Gullström, C.--O., Hauenstein, F., Heijkenskjöld, L., Hejny, V., Bashkanov, M., Hodana, M., Höistad, B., Hüsken, N., Jany, A., Jany, B. R., Johansson, T., Kamys, B., Kemmerling, G., Khan, F. A., Khoukaz, A., Bergmann, F. S., Kirillov, D. A., Kistryn, S., Kleines, H., Kłos, B., Krapp, M., Krzemień, W., Kulessa, P., Kupść, A., Lalwani, K., Lersch, D., Berłowski, M., Lorentz, B., Magiera, A., Maier, R., Marciniewski, P., Mariański, B., Mikirtychiants, M., Morsch, H.-P., Moskal, P., Ohm, H., Ozerianska, I., Bhatt, H., Perez del Rio, E., Piskunov, N. M., Podkopał, P., Prasuhn, D., Pricking, A., Pysz, K., Pyszniak, A., Redmer, C. F., Ritman, J., Roy, A., Büscher, M., Rudy, Z., Sawant, S., Schadmand, S., Sefzick, T., Serdyuk, V., Siudak, R., Skorodko, T., Skurzok, M., Smyrski, J., Sopov, V., Calén, H., Stassen, R., Stepaniak, J., Stephan, E., Sterzenbach, G., Stockhorst, H., Ströher, H., Szczurek, A., Täschner, A., Trzciński, A., Varma, R., Ciepał, I., Wolke, M., Wrońska, A., Wüstner, P., Wurm, P., Yamamoto, A., Yurev, L., Zabierowski, J., Zink, A., Złomańczuk, J., and Zurek, M.
Subjects: +n+p+p%22">deuteron p --> n p p, partial wave analysis, Juelich COSY PS, dibaryon, pole [resonance], kinematics, beam [deuteron], scattering [p n], spectator [p], differential cross section, target [hydrogen], analyzing power, ddc:530, angular distribution, WASA, experimental results
Published: 2020
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3. Differential cross sections for neutron-proton scattering in the region of the d∗(2380) dibaryon resonance

Author: Adlarson, P., Augustyniak, W., Bardan, W., Bashkanov, M., Bergmann, F. S., Berłowski, M., Bhatt, H., Büscher, M., Calén, H., Ciepał, I., Clement, H., Coderre, D., Czerwiński, E., Demmich, K., Doroshkevich, E., Engels, R., Erven, A., Erven, W., Eyrich, W., Fedorets, P., Föhl, K., Fransson, K., Goldenbaum, F., Goslawski, P., Goswami, A., Grigoryev, Kirill, Gullström, C.--O., Hauenstein, F., Heijkenskjöld, L., Hejny, V., Hodana, M., Höistad, B., Hüsken, N., Jany, A., Jany, B. R., Johansson, T., Kamys, B., Kemmerling, G., Khan, F. A., Khoukaz, A., Kirillov, D. A., Kistryn, S., Kleines, H., Kłos, B., Krapp, M., Krzemień, W., Kulessa, P., Kupść, A., Lalwani, K., Lersch, D., Lorentz, B., Magiera, A., Maier, R., Marciniewski, P., Mariański, B., Mikirtychiants, M., Morsch, H.-P., Moskal, P., Ohm, H., Ozerianska, I., Perez Del Rio, E., Piskunov, N. M., Podkopał, P., Prasuhn, D., Pricking, A., Pysz, K., Pyszniak, A., Redmer, C. F., Ritman, J., Roy, A., Rudy, Z., Sawant, S., Schadmand, S., Sefzick, T., Serdyuk, V., Siudak, R., Skorodko, T., Skurzok, M., Smyrski, J., Sopov, V., Stassen, R., Stepaniak, J., Stephan, E., Sterzenbach, G., Stockhorst, H., Ströher, H., Szczurek, A., Täschner, A., Trzciński, A., Varma, R., Wolke, M., Wrońska, A., Wüstner, P., Wurm, P., Yamamoto, A., Yurev, L., Zabierowski, J., Zink, A., Złomańczuk, J., Zurek, M., Workman, R. L., Briscoe, W. J., Strakovsky, I. I., and Švarc, A.
Subjects: resonance: pole, p: spectator, p n: scattering, partial wave analysis, Juelich COSY PS, deuteron: beam, dibaryon, kinematics, differential cross section, analyzing power, angular distribution, WASA, +n+p+p%22">deuteron p --> n p p, experimental results, hydrogen: target
Abstract: Physical review / C 102(1), 015204 (2020). doi:10.1103/PhysRevC.102.015204, Published by The American Institute of Physics, Woodbury, NY
Published: 2020
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4. The impact of climate change on incomes and convergence in Africa

Author: Baarsch, F, Granadillos, JR, Hare, W, Knaus, M, Krapp, M, Schaeffer, M, Lotze-Campen, H, Krapp, Mario [0000-0002-2599-0683], and Apollo - University of Cambridge Repository
Subjects: Inequality, Africa, Macroeconomics, Climate change, Convergence
Abstract: © 2019 Elsevier Ltd Climate change is projected to detrimentally affect African countries’ economic development, while income inequalities across economies is among the highest on the planet. However, it is projected that income levels would converge on the continent. Hitherto there is limited evidence on how climate change could affect projected income convergence, accelerating, slowing down, or even reversing this process. Here, we analyze convergence considering climate-change damages, by employing an economic model embedding the three dimensions of risks at the country-level: exposure, vulnerability and hazards. The results show (1) with historical mean climate-induced losses between 10 and 15 percent of GDP per capita growth, the majority of African economies are poorly adapted to their current climatic conditions, (2) Western and Eastern African countries are projected to be the most affected countries on the continent and (3) As a consequence of these heightened impacts on a number of countries, inequalities between countries are projected to widen in the high warming scenario compared to inequalities in the low and without warming scenarios. To mitigate the impacts of economic development and inequalities across countries, we stress (1) the importance of mitigation ambition and Africa's leadership in keeping global mean temperature increase below 1.5 °C, (2) the need to address the current adaptation deficit as soon as possible, (3) the necessity to integrate quantitatively climate risks in economic and development planning and finally (4) we advocate for the generalization of a special treatment for the most vulnerable countries to access climate-related finance. The analysis raises issues on the ability of African countries to reach their SDGs targets and the potential increasing risk of instability, migration across African countries, of decreased trade and economic cooperation opportunities as a consequence of climate change – exacerbating its negative consequences.
Published: 2020

5. The impact of climate change on incomes and convergence in Africa

Author: Baarsch, F, Granadillos, Hare, W, Knaus, M, Krapp, M, Schaeffer, M, and Lotze-Campen, H
Subjects: Inequality, Africa, Macroeconomics, Climate change, Convergence
Abstract: © 2019 Elsevier Ltd Climate change is projected to detrimentally affect African countries’ economic development, while income inequalities across economies is among the highest on the planet. However, it is projected that income levels would converge on the continent. Hitherto there is limited evidence on how climate change could affect projected income convergence, accelerating, slowing down, or even reversing this process. Here, we analyze convergence considering climate-change damages, by employing an economic model embedding the three dimensions of risks at the country-level: exposure, vulnerability and hazards. The results show (1) with historical mean climate-induced losses between 10 and 15 percent of GDP per capita growth, the majority of African economies are poorly adapted to their current climatic conditions, (2) Western and Eastern African countries are projected to be the most affected countries on the continent and (3) As a consequence of these heightened impacts on a number of countries, inequalities between countries are projected to widen in the high warming scenario compared to inequalities in the low and without warming scenarios. To mitigate the impacts of economic development and inequalities across countries, we stress (1) the importance of mitigation ambition and Africa's leadership in keeping global mean temperature increase below 1.5 °C, (2) the need to address the current adaptation deficit as soon as possible, (3) the necessity to integrate quantitatively climate risks in economic and development planning and finally (4) we advocate for the generalization of a special treatment for the most vulnerable countries to access climate-related finance. The analysis raises issues on the ability of African countries to reach their SDGs targets and the potential increasing risk of instability, migration across African countries, of decreased trade and economic cooperation opportunities as a consequence of climate change – exacerbating its negative consequences.
Published: 2019
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6. Determination of the spin triplet p Λ scattering length from the final state interaction in the p - p→pK+ Λ reaction

Author: Hauenstein, F., Borodina, E., Clement, H., Doroshkevich, E., Dzhygadlo, R., Ehrhardt, K., Eyrich, W., Gast, W., Gillitzer, A., Grzonka, D., Haidenbauer, J., Hanhart, C., Jowzaee, S., Kilian, K., Klaja, P., Kober, L., Krapp, M., Mertens, M., Moskal, P., Ritman, J., Roderburg, E., Röder, M., Schroeder, W., Sefzick, T., Wintz, P., and Wüstner, P.
Subjects: Physik (inkl. Astronomie)
Published: 2017

7. Determination of the spin triplet p Λ scattering length from the final state interaction in the p ⃗ p → p K + Λ reaction

Author: Hauenstein, Florian, Borodina, E., Haidenbauer, J., Hanhart, C., Jowzaee, S., Kilian, K., Klaja, P., Kober, L., Krapp, M., Mertens, M., Ritman, J., Roderburg, E., Clement, H., Röder, M., Schroeder, W., Sefzick, T., Wintz, P., Wüstner, P., Moskal, P., Doroshkevich, E., Dzhygadlo, R., Ehrhardt, K., Eyrich, W., Gast, W., Gillitzer, A., and Grzonka, D.
Subjects: ddc:530, Nuclear Experiment
Abstract: The ⃗pp→pK+Λ reaction has been measured with the COSY-TOF detector at a beam momentum of 2.7GeV/c. The polarized proton beam enables the measurement of the beam analyzing power by the asymmetry of the produced kaon (AKN). This observable allows the pΛ spin triplet scattering length to be extracted for the first time model independently from the final state interaction in the reaction. The obtained value is at=(−2.55+0.72−1.39stat.±0.6syst.±0.3theo.)fm. This value is compatible with theoretical predictions and results from model-dependent analyses.
Published: 2017
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8. First Model-Independent Measurement of the Spin Triplet $p\Lambda$ Scattering Length from Final State Interaction in the $\vec{p}p \rightarrow pK^{+}\Lambda$ Reaction

Author: Collaboration, COSY-TOF, Hauenstein, F., Borodina, E., Clement, H., Doroshkevich, E., Dzhygadlo, R., Ehrhardt, K., Eyrich, W., Gast, W., Gillitzer, A., Grzonka, D., Haidenbauer, J., Hanhart, C., Jowzaee, S., Kilian, K., Klaja, P., Kober, L., Krapp, M., Mertens, M., Moskal, P., Ritman, J., Roderburg, E., Röder, M., Schroeder, W., Sefzick, T., Wintz, P., and Wüstner, P.
Subjects: High Energy Physics::Experiment, Nuclear Experiment
Abstract: The $\vec{p}p \rightarrow pK^{+}\Lambda$ reaction has been measured with the COSY-TOF detector at a beam momentum of $2.7\,\mathrm{GeV}/c$. The polarized proton beam enables the measurement of the beam analyzing power by the asymmetry of the produced kaon ($A_N^{K}$). This observable allows the $p\Lambda$ spin triplet scattering length to be extracted for the first time model independently from the final-state interaction in the reaction. The obtained value is $a_{t} = (-2.55 ^{+0.72}_{-1.39} {}_{\textrm{stat.}} \pm 0.6_{\textrm{syst.}} \pm 0.3_{\textrm{theo.}})\mathrm{fm}$. This value is compatible with theoretical predictions and results from model-dependent analyses., Comment: Revised version as accepted for publication in PRC
Published: 2016

9. First Model-Independent Measurement of the Spin Triplet $p��$ Scattering Length from Final State Interaction in the $\vec{p}p \rightarrow pK^{+}��$ Reaction

Author: TOF Collaboration, Hauenstein, F., Borodina, E., Clement, H., Doroshkevich, E., Dzhygadlo, R., Ehrhardt, K., Eyrich, W., Gast, W., Gillitzer, A., Grzonka, D., Haidenbauer, J., Hanhart, C., Jowzaee, S., Kilian, K., Klaja, P., Kober, L., Krapp, M., Mertens, M., Moskal, P., Ritman, J., Roderburg, E., R��der, M., Schroeder, W., Sefzick, T., Wintz, P., and W��stner, P.
Subjects: FOS: Physical sciences, High Energy Physics::Experiment, Nuclear Experiment (nucl-ex), Nuclear Experiment
Abstract: The $\vec{p}p \rightarrow pK^{+}��$ reaction has been measured with the COSY-TOF detector at a beam momentum of $2.7\,\mathrm{GeV}/c$. The polarized proton beam enables the measurement of the beam analyzing power by the asymmetry of the produced kaon ($A_N^{K}$). This observable allows the $p��$ spin triplet scattering length to be extracted for the first time model independently from the final-state interaction in the reaction. The obtained value is $a_{t} = (-2.55 ^{+0.72}_{-1.39} {}_{\textrm{stat.}} \pm 0.6_{\textrm{syst.}} \pm 0.3_{\textrm{theo.}})\mathrm{fm}$. This value is compatible with theoretical predictions and results from model-dependent analyses., Revised version as accepted for publication in PRC
Published: 2016
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10. High precision measurement of the associated strangeness production in proton proton interactions

Author: Collaboration, COSY-TOF, Jowzaee, S., Borodina, E., Clement, H., Doroshkevich, E., Dzhygadlo, R., Ehrhardt, K., Eyrich, W., Gast, W., Gillitzer, A., Grzonka, D., Hauenstein, F., Klaja, P., Kober, L., Kilian, K., Krapp, M., Mertens, M., Moskal, P., Ritman, J., Roderburg, E., Röder, M., Schroeder, W., Sefzick, T., Smyrski, J., Wintz, P., and Wüstner, P.
Subjects: FOS: Physical sciences, Nuclear Experiment (nucl-ex), Nuclear Experiment
Abstract: A new high precision measurement of the reaction pp -> pK+Lambda at a beam momentum of 2.95 GeV/c with more than 200,000 analyzed events allows a detailed analysis of differential observables and their inter-dependencies. Correlations of the angular distributions with momenta are examined. The invariant mass distributions are compared for different regions in the Dalitz plots. The cusp structure at the N Sigma threshold is described with the Flatt�� formalism and its variation in the Dalitz plot is analyzed., accepted for publication in Eur. Phys. J.A
Published: 2015
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11. Neutron-Proton Scattering in the Context of the $d^*$(2380) Resonance

Author: Adlarson, P., Augustyniak, W., Clement, H., Zabierowski, J., Zieliński, M. J., Zink, A., Złomańczuk, J., Żuprański, P., Żurek, M., Workman, R. L., Briscoe, W. J., Strakovsky, I. I., WASA-at-COSY Collaboration, Coderre, D., Czerwiński, E., Demmich, K., Doroshkevich, E., Engels, R., Erven, A., Erven, W., Eyrich, W., Fedorets, P., Bardan, W., Föhl, K., Fransson, K., Goldenbaum, F., Goslawski, P., Goswami, A., Grigoryev, K., Gullström, C.-O., Hauenstein, F., Heijkenskjöld, L., Hejny, V., Bashkanov, M., Hodana, M., Höistad, B., Hüsken, N., Jany, A., Jany, B. R., Jarczyk, L., Johansson, T., Kamys, B., Kemmerling, G., Khan, F. A., Bergmann, F. S., Khoukaz, A., Kirillov, D. A., Kistryn, S., Kleines, H., Kłos, B., Krapp, M., Krzemień, W., Kulessa, P., Kupść, A., Lalwani, K., Berłowski, M., Lersch, D., Lorentz, B., Magiera, A., Maier, R., Marciniewski, P., Mariański, B., Mikirtychiants, M., Morsch, H.-P., Moskal, P., Ohm, H., Bhatt, H., Ozerianska, I., Perez del Rio, E., Piskunov, N. M., Podkopał, P., Prasuhn, D., Pricking, A., Pszczel, D., Pysz, K., Pyszniak, A., Redmer, C. F., Büscher, M., Ritman, J., Roy, A., Rudy, Z., Sawant, S., Schadmand, S., Sefzick, T., Serdyuk, V., Siudak, R., Skorodko, T., Calén, H., Skurzok, M., Smyrski, J., Sopov, V., Stassen, R., Stepaniak, J., Stephan, E., Sterzenbach, G., Stockhorst, H., Stroeher, Hans, Szczurek, A., Ciepał, I., Täschner, A., Trzciński, A., Varma, R., Wagner, G. J., Wolke, M., Wrońska, A., Wüstner, P., Wurm, P., Yamamoto, A., and Yurev, L.
Subjects: Np Elastic-Scattering, Nuclear and High Energy Physics, Nucleon-Scattering, Partial wave analysis, Nuclear Theory, Hexaquark, Analyzing Power, FOS: Physical sciences, Context (language use), Double-Pionic Fusion, High Energy Physics - Experiment, Nuclear physics, High Energy Physics - Experiment (hep-ex), Proton scattering, Neutron, ddc:530, Nuclear Experiment (nucl-ex), Nuclear Experiment, Partial-Wave Analysis, Physics, Elastic scattering, Scattering, Total Cross-Section, Resonance (chemistry), Intermediate Energies, Isospin Decomposition, Delta-Sigma-T, Spin Observables
Abstract: New data on quasifree polarized neutron-proton scattering in the region of the recently observed $d^{\ast}$ resonance structure are obtained by exclusive and kinematically complete high-statistics measurements with WASA at COSY. This paper details the determination of the beam polarization, checks of the quasifree character of the scattering process, on all obtained $A_{y}$ angular distributions and on the new partial-wave analysis, which includes the new data producing a resonance pole in $^{3}D_{3}−^{3}G_{3}$ coupled partial waves at (2380 $\pm$ 10−i40 $\pm$ 5) MeV—in accordance with the $d^{\ast}$ dibaryon resonance hypothesis. The effect of the new partial-wave solution on the description of total and differential cross-section data as well as specific combinations of spin-correlation and spin-transfer observables available from COSY-ANKE measurements at $T_{d}$=2.27 GeV is discussed.
Published: 2014
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12. Cross section ratio and angular distributions of the reaction p + d -> 3He + eta at 48.8 MeV and 59.8 MeV excess energy

Author: Adlarson, P., Augustyniak, W., Bardan, W., Bashkanov, M., Bergmann, F. S., Ber��owski, M., Bhatt, H., B��scher, M., Cal��n, H., Ciepa��, I., Clement, H., Coderre, D., Czerwi��ski, E., Demmich, K., Doroshkevich, E., Engels, R., Erven, A., Erven, W., Eyrich, W., Fedorets, P., F��hl, K., Fransson, K., Goldenbaum, F., Goslawski, P., Goswami, A., Grigoryev, K., Gullstr��m, C. -O., Hauenstein, F., Heijkenskj��ld, L., Hejny, V., Hodana, M., H��istad, B., H��sken, N., Jany, A., Jany, B. R., Jarczyk, L., Johansson, T., Kamys, B., Kemmerling, G., Khan, F. A., Khoukaz, A., Kirillov, D. A., Kistryn, S., K��os, B., Kleines, H., Krapp, M., Krzemie��, W., Kulessa, P., Kup��, A., Lalwani, K., Lersch, D., Lorentz, B., Magiera, A., Maier, R., Marciniewski, P., Maria��ski, B., Mikirtychiants, M., Morsch, H. --P., Moskal, P., Ohm, H., Ozerianska, I., Passfeld, A., del Rio, E. Perez, Piskunov, N. M., Podkopa��, P., Prasuhn, D., Pricking, A., Pszczel, D., Pysz, K., Pyszniak, A., Redmer, C. F., Ritman, J., Roy, A., Rudy, Z., Sawant, S., Schadmand, S., Sefzick, T., Serdyuk, V., Siudak, R., Skorodko, T., Skurzok, M., Smyrski, J., Sopov, V., Stassen, R., Stepaniak, J., Stephan, E., Sterzenbach, G., Stockhorst, H., Str��her, H., Szczurek, A., T��schner, A., Trzci��ski, A., Varma, R., Wagner, G. J., W��glorz, W., Wolke, M., Wro��ska, A., W��stner, P., Wurm, P., Yamamoto, A., Yurev, L., Zabierowski, J., Zieli��ski, M. J., Zink, A., Z��oma��czuk, J., ��upra��ski, P., and ��urek, M.
Subjects: Physics::Accelerator Physics, FOS: Physical sciences, Nuclear Experiment (nucl-ex), Nuclear Experiment
Abstract: We present new data for angular distributions and on the cross section ratio of the p + d -> 3He + eta reaction at excess energies of Q = 48.8 MeV and Q = 59.8 MeV. The data have been obtained at the WASA-at-COSY experiment (Forschungszentrum J��lich) using a proton beam and a deuterium pellet target. While the shape of obtained angular distributions show only a slow variation with the energy, the new results indicate a distinct and unexpected total cross section fluctuation between Q = 20 MeV and Q = 60 MeV, which might indicate the variation of the production mechanism within this energy interval., 9 pages, 9 figures
Published: 2014
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13. Cross section ratio and angular distributions of the reaction $p + d \rightarrow ^{3}He + \it{\eta}$ at 48.8 MeV and 59.8 MeV excess energy

Author: Adlarson, P., Augustyniak, W., Bardan, Wiktor, Bashkanov, M., Bergmann, F. S., Berłowski, M., Bhatt, H., Büscher, M., Calén, H., Ciepał, Izabela, Clement, H., Coderre, D., Czerwiński, Eryk, Demmich, K., Doroshkevich, E., Engels, R., Erven, A., Erven, W., Eyrich, W., Fedorets, P., Föhl, K., Fransson, K., Goldenbaum, F., Goslawski, P., Goswami, A., Grigoryev, K., Gullström, C.-O., Hauenstein, F., Heijkenskjöld, L., Hejny, V., Hodana, Małgorzata, Höistad, B., Hüsken, N., Jany, Anna, Jany, Benedykt, Jarczyk, Lucjan, Johansson, T., Kamys, Bogusław, Kemmerling, G., Khan, F. A., Khoukaz, A., Kirillov, D. A., Kistryn, Stanisław, Kłos, B., Kleines, H., Krapp, M., Krzemień, Wojciech, Kulessa, P., Kupść, A., Lalwani, K., Lersch, D., Lorentz, B., Magiera, Andrzej, Maier, R., Marciniewski, P., Mariański, B., Mikirtychiants, M., Morsch, H.-P., Moskal, Paweł, Ohm, H., Schätti - Ozerianska, Iryna, Passfeld, A., Perez del Rio, Elena, Piskunov, N. M., Podkopał, Paweł, Prasuhn, D., Pricking, A., Pszczel, D., Pysz, K., Pyszniak, Andrzej, Redmer, C. F., Ritman, J., Roy, A., Rudy, Zbigniew, Sawant, S., Schadmand, S., Sefzick, T., Serdyuk, V., Siudak, R., Skorodko, T., Skurzok, Magdalena, Smyrski, Jerzy, Sopov, V., Stassen, R., Stepaniak, J., Stephan, E., Sterzenbach, G., Stockhorst, H., Ströher, H., Szczurek, A., Täschner, A., Trzciński, A., Varma, R., Wagner, G. J., Węglorz, W., Wolke, M., Wrońska, Aleksandra, Wüstner, P., Wurm, P., Yamamoto, A., Yurev, L., Zabierowski, J., Zieliński, Marcin, Zink, A., Złomańczuk, J., Żuprański, P., and Żurek, M.
Subjects: Physics::Accelerator Physics, Nuclear Experiment
Abstract: We present new data for angular distributions and on the cross section ratio of the $p + d \rightarrow ^{3}He + \it{\eta}$ reaction at excess energies of $\it{Q}$ = 48.8 MeV and $\it{Q}$ = 59.8 MeV. The data have been obtained at the WASA-at-COSY experiment (Forschungszentrum Jülich) using a proton beam and a deuterium pellet target. While the shape of obtained angular distributions show only a slow variation with the energy, the new results indicate a distinct and unexpected total cross section fluctuation between $\it{Q}$ = 20 MeV and $\it{Q}$ = 60 MeV, which might indicate the variation of the production mechanism within this energy interval.
Published: 2014

14. Measurement of the $pn \to pp\pi^0\pi^-$ Reaction in Search for the Recently Observed Resonance Structure in $d\pi^0\pi^0$ and $d\pi^+\pi^-$ systems

Author: Adlarson, P., Augustyniak, W., Bardan, W., Bashkanov, M., Bergmann, F. S., Berłowski, M., Bhatt, H., Büscher, M., Calén, H., Ciepał, I., Clement, H., Coderre, D., Czerwiński, E., Demmich, K., Doroshkevich, E., Engels, R., Erven, W., Eyrich, W., Fedorets, P., Föhl, K., Fransson, K., Goldenbaum, F., Goslawski, P., Goswami, A., Grigoryev, K., Gullström, C. --O., Hauenstein, F., Heijkenskjöld, L., Hejny, V., Hinterberger, F., Hodana, M., Höistad, B., Jany, A., Jany, B. R., Jarczyk, L., Johansson, T., Kamys, B., Kemmerling, G., Khan, F. A., Khoukaz, A., Kirillov, D. A., Kistryn, S., Klaja, J., Kleines, H., Kłos, B., Krapp, M., Krzemień, W., Kulessa, P., Kupść, A., Lalwani, K., Lersch, D., Li, L., Lorentz, B., Magiera, A., Maier, R., Marciniewski, P., Mariański, B., Mikirtychiants, M., Morsch, H. --P., Moskal, P., Nandi, B. K., Ohm, H., Ozerianska, I., del Rio, E. Perez, Piskunov, N. M., Pluciński, P., Podkopał, P., Prasuhn, D., Pricking, A., Pszczel, D., Pysz, K., Pyszniak, A., Redmer, C. F., Ritman, J., Roy, A., Rudy, Z., Sawant, S., Schmidt, A., Schadmand, S., Sefzick, T., Serdyuk, V., Shah, N., Siemaszko, M., Siudak, R., Skorodko, T., Skurzok, M., Smyrski, J., Sopov, V., Stassen, R., Stepaniak, J., Stephan, E., Sterzenbach, G., Stockhorst, H., Ströher, H., Szczurek, A., Tolba, T., Trzciński, A., Varma, R., Wagner, G. J., Węglorz, W., Wolke, M., Wrońska, A., Wüstner, P., Wurm, P., Yamamoto, A., Yuan, X., Zabierowski, J., Zheng, C., Zieliński, M. J., Zipper, W., Złomańczuk, J., Żuprański, P., and Żurek, M.
Subjects: Nuclear Experiment
Abstract: Exclusive measurements of the quasi-free $pn \to pp\pi^0\pi^-$ reaction have been performed by means of $pd$ collisions at $T_p$ = 1.2 GeV using the WASA detector setup at COSY. Total and differential cross sections have been obtained covering the energy region $\sqrt s$ = (2.35 - 2.46) GeV, which includes the region of the ABC effect and its associated resonance structure. No ABC effect, {\it i.e.} low-mass enhancement is found in the $\pi^0\pi^-$-invariant mass spectrum -- in agreement with the constraint from Bose statistics that the isovector pion pair can not be in relative s-wave. At the upper end of the covered energy region $t$-channel processes for Roper, $\Delta(1600)$ and $\Delta\Delta$ excitations provide a reasonable description of the data, but at low energies the measured cross sections are much larger than predicted by such processes. Adding a resonance amplitude for the resonance at $m$=~2.37 GeV with $\Gamma$ =~70 MeV and $I(J^P)=~0(3^+)$ observed recently in $pn \to d\pi^0\pi^0$ and $pn \to d\pi^+\pi^-$ reactions leads to an agreement with the data also at low energies.
Published: 2013

15. Final-State Interactions in the Process pp -> pKLambda

Author: Röder, M., Borodina, E., Clement, H., Doroshkevich, E., Dzhygadlo, R., Ehrhardt, K., Erhardt, A., Eyrich, W., Gast, W., Gillitzer, A., Grzonka, D., Haidenbauer, J., Hanhart, C., Hauenstein, F., Klaja, P., Kober, L., Kilian, K., Krapp, M., Mertens, M., Ritman, J., Roderburg, E., Schroeder, W., Sefzick, T., Sibirtsev, A., Wintz, P., and Wüstner, P.
Subjects: Nuclear Experiment
Abstract: The possibility to determine the pLambda scattering length from the final-state interaction in the reaction pp->pKLambda is investigated experimentally. From a transversely polarized measurement, the K analyzing power (A_N) which, in principle, allows one to extract the spin triplet scattering length is studied. An unexpected energy dependence of the forward/backward symmetric part of A_N is found. The influence of N*-resonances on the pLambda invariant mass spectrum is investigated by exploiting the large acceptance for the process pp->pKLambda->pKppi and is found to be the main source of uncertainty for determining the pLambda scattering length.
Published: 2013

16. Investigation of the dd -> 3He n \pi 0 reaction with the FZ J\'ulich WASA-at-COSY facility

Author: Collaboration, WASA-at-COSY, Adlarson, P., Augustyniak, W., Bardan, W., Bashkanov, M., Bergmann, F. S., Berłowski, M., Bhatt, H., Büscher, M., Calén, H., Ciepał, I., Clement, H., Coderre, D., Czerwiński, E., Demmich, K., Doroshkevich, E., Engels, R., Erven, W., Eyrich, W., Fedorets, P., Föhl, K., Fransson, K., Goldenbaum, F., Goslawski, P., Goswami, A., Grigoryev, K., Gullström, C. --O., Hanhart, C., Hauenstein, F., Heijkenskjöld, L., Hejny, V., Hinterberger, F., Hodana, M., Höistad, B., Jany, A., Jany, B. R., Jarczyk, L., Johansson, T., Kamys, B., Kemmerling, G., Khan, F. A., Khoukaz, A., Kirillov, D. A., Kistryn, S., Klaja, J., Kleines, H., Kłos, B., Krapp, M., Krzemień, W., Kulessa, P., Kupść, A., Lalwani, K., Lersch, D., Li, L., Lorentz, B., Magiera, A., Maier, R., Marciniewski, P., Mariański, B., Mikirtychiants, M., Morsch, H. --P., Moskal, P., Nandi, B. K., Ohm, H., Ozerianska, I., del Rio, E. Perez, Piskunov, N. M., Pluciński, P., Podkopał, P., Prasuhn, D., Pricking, A., Pszczel, D., Pysz, K., Pyszniak, A., Redmer, C. F., Ritman, J., Roy, A., Rudy, Z., Sawant, S., Schmidt, A., Schadmand, S., Sefzick, T., Serdyuk, V., Shah, N., Siemaszko, M., Siudak, R., Skorodko, T., Skurzok, M., Smyrski, J., Sopov, V., Stassen, R., Stepaniak, J., Stephan, E., Sterzenbach, G., Stockhorst, H., Ströher, H., Szczurek, A., Tolba, T., Trzciński, A., Varma, R., Wagner, G. J., Węglorz, W., Wolke, M., Wrońska, A., Wüstner, P., Wurm, P., Yamamoto, A., Yuan, X., Zabierowski, J., Zheng, C., Zieliński, M. J., Zipper, W., Złomańczuk, J., Żuprański, P., and Żurek, M.
Subjects: interaction [pi], expansion [partial wave], model [nuclear reaction], 0.6 GeV/c/nucleon, measured [channel cross section], Juelich COSY PS, angular dependence [differential cross section], +helium+n+pi0%22">deuteron deuteron --> helium n pi0, ddc:530, hadroproduction [pi0], WASA, Nuclear Experiment, exclusive reaction [deuteron deuteron], experimental results
Abstract: An exclusive measurement of the dd -> 3He n \pi 0 reaction was carried at a beam momentum of p = 1.2 GeV/c using the WASA-at-COSY facility. For the first time data on the total cross section as well as differential distributions were obtained. The data are described with a phenomenological approach based on a combination of a quasi-free model and a partial wave expansion for three-body reaction. The total cross section is found to be \sigma(tot) = (2.89 +- 0.01(stat) +- 0.06(sys) +- 0.29(norm)) \mu b. The contribution of the quasi-free processes (with the neutron being target or beam spectator) accounts for 38% of the total cross section and dominates the differential distributions in specific regions of the phase space. The remaining part of the cross section can be described within a partial wave decomposition indicating the significance of p-wave contributions in the final state., Comment: 9 pages, 7 figures
Published: 2013
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17. Search for a dark photon in the $\pi^0 \to e^+e^-\gamma$ decay

Author: Adlarson, P., Augustyniak, W., Ciepal, I., Trzcinski, A., Varma, R., Wagner, G. J., Weglorz, W., Wirzba, Andreas, Wolke, Magnus, Wronska, A., Wüstner, Peter, Wurm, Patrick, Yamamoto, A., Clement, H., Zabierowski, J., Zielinski, M. J., Zipper, W., Zlomanczuk, J., Zupranski, P., Zurek, M., Coderre, Daniel, Czerwinski, E., Demmich, K., Doroshkevich, E., Engels, Ralf W., Erven, Wilhelm, Eyrich, W., Fedorets, Pavel, Bardan, W., Föhl, K., Fransson, K., Goldenbaum, Frank, Goslawski, P., Goswami, Ankita, Grigoryev, Kirill, Gullström, C. -O., Hauenstein, Florian, Heijkenskjöld, L., Hejny, Volker, Bashkanov, M., Hinterberger, F., Hodana, Malgorzata, Höistad, B., Jany, A., Jany, Benedykt, Jarczyk, L., Johansson, T., Kamys, B., Kemmerling, Günter, Khan, Farha Anjum, Bergmann, F. S., Khoukaz, A., Kistryn, S., Klaja, J., Kleines, Harald, Kirillov, D. A., Klos, B., Krapp, M., Krzemien, W., Kulessa, Pawel, Kupsc, Andrzej, Berlowski, M., Kuzmin, A., Lalwani, K., Lersch, Daniel, Li, L., Lorentz, Bernd, Magiera, A., Maier, Rudolf, Marciniewski, P., Marianski, B., Meißner, Ulf-G., Bhatt, Himani, Mikirtychyants, Maxim, Morsch, H. -P., Moskal, Pawel, Nandi, B. K., Ohm, Henner, Ozerianska, I., Perez del Rio, E., Piskunov, N. M., Plucinski, P., Podkopal, P., Bondar, A., Prasuhn, Dieter, Pricking, A., Pszczel, D., Pysz, K., Pyszniak, A., Redmer, F., Ritman, James, Roy, A., Rudy, Z., Sawant, S., Büscher, Markus, Schadmand, Susan, Schmidt, A., Sefzick, Thomas, Serdyuk, Valeriy, Shah, N., Shwartz, B., Siemaszko, M., Siudak, R., Skorodko, T., Skruzok, M., Calen, Hans, Smyrski, J., Sopov, V., Stassen, Rolf, Stepaniak, J., Stephan, E., Sterzenbach, Guenter, Stockhorst, Hans, Stroeher, Hans, Szczurek, A., and Tolba, T.
Subjects: branching ratio: upper limit [pi0], +positron+electron+photon%22">pi0 --> positron electron photon, 0.55 GeV-kin, radiative decay [pi0], interaction [p p], Juelich COSY PS, High Energy Physics - Experiment, High Energy Physics - Phenomenology, magnetic moment [muon], +2p+pi0%22">p p --> 2p pi0, ddc:530, High Energy Physics::Experiment, WASA, Nuclear Experiment, mixing [photon], search for [U boson], mass spectrum [electron positron], experimental results, +U+boson+photon%22">pi0 --> U boson photon
Abstract: The presently world largest data sample of pi0 --> gamma e+e- decays containing nearly 5E5 events was collected using the WASA detector at COSY. A search for a dark photon U produced in the pi0 --> gamma U --> gamma e+e- decay from the pp-->pp\pi^0 reaction was carried out. An upper limit on the square of the U-gamma mixing strength parameter epsilon^2 of 5e-6 at 90% CL was obtained for the mass range 20 MeV, Comment: 16 pages, 8 figures; improved analysis extending the exclusion region to 20 MeV
Published: 2013
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18. Search for a dark photon in the $��^0 \to e^+e^-��$ decay

Author: COSY Collaboration, Adlarson, P., Augustyniak, W., Bardan, W., Bashkanov, M., Bergmann, F. S., Ber��owski, M., Bhatt, H., Bondar, A., B��scher, M., Cal��n, H., Ciepa��, I., Clement, H., Coderre, D., Czerwi��ski, E., Demmich, K., Doroshkevich, E., Engels, R., Erven, W., Eyrich, W., Fedorets, P., F��hl, K., Fransson, K., Goldenbaum, F., Goslawski, P., Goswami, A., Grigoryev, K., Gullstr��m, C. -O., Hauenstein, F., Heijkenskj��ld, L., Hejny, V., Hinterberger, F., Hodana, M., H��istad, B., Jany, A., Jany, B. R., Jarczyk, L., Johansson, T., Kamys, B., Kemmerling, G., Khan, F. A., Khoukaz, A., Kistryn, S., Klaja, J., Kleines, H., K��os, B., Krapp, M., Krzemie��, W., Kulessa, P., Kup��, A., Kuzmin, A., Lalwani, K., Lersch, D., Li, L., Lorentz, B., Magiera, A., Maier, R., Marciniewski, P., Maria��ski, B., Mei��ner, U. -G., Mikirtychiants, M., Morsch, H. -P., Moskal, P., Nandi, B. K., Ohm, H., Ozerianska, I., del Rio, E. Perez, Piskunov, N., Pluci��ski, P., Podkopa��, P., Prasuhn, D., Pricking, A., Pszczel, D., Pysz, K., Pyszniak, A., Redmer, C. F., Ritman, J., Roy, A., Rudy, Z., Sawant, S., Schadmand, S., Schmidt, A., Sefzick, T., Serdyuk, V., Shah, N., Shwartz, B., Siemaszko, M., Siudak, R., Skorodko, T., Skurzok, M., Smyrski, J., Sopov, V., Stassen, R., Stepaniak, J., Stephan, E., Sterzenbach, G., Stockhorst, H., Str��her, H., Szczurek, A., Tolba, T., Trzci��ski, A., Varma, R., Wagner, G. J., W��glorz, W., Wirzba, A., Wolke, M., Wro��ska, A., W��stner, P., Wurm, P., Yamamoto, A., Zabierowski, J., Zieli��ski, M. J., Zipper, W., Z��oma��czuk, J., ��upra��ski, P., and ��urek, M.
Subjects: High Energy Physics - Experiment (hep-ex), High Energy Physics - Phenomenology (hep-ph), FOS: Physical sciences, High Energy Physics::Experiment, Nuclear Experiment (nucl-ex), Nuclear Experiment
Abstract: The presently world largest data sample of pi0 --> gamma e+e- decays containing nearly 5E5 events was collected using the WASA detector at COSY. A search for a dark photon U produced in the pi0 --> gamma U --> gamma e+e- decay from the pp-->pp��^0 reaction was carried out. An upper limit on the square of the U-gamma mixing strength parameter epsilon^2 of 5e-6 at 90% CL was obtained for the mass range 20 MeV, 16 pages, 8 figures; improved analysis extending the exclusion region to 20 MeV
Published: 2013
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19. Search for a dark photon in the pi(0) -> e(+)e(-)gamma decay

Author: ADLARSON, P, AUGUSTYNIAK, W, BARDAN, W, BASHKANOV, M, BERGMANN, FS, BERLOWSKI, M, BHATT, H, BONDAR, A, BUSCHER, M, CALEN, H, CIEPAL, I, CLEMENT, H, CODERRE, D, CZERWINSKI, E, DEMMICH, K, DOROSHKEVICH, E, ENGELS, R, ERVEN, W, EYRICH, W, FEDORETS, P, FOHL, K, FRANSSON, K, GOLDENBAUM, E, GOSLAWSKI, P, GOSWAMI, A, GRIGORYEV, K, GULLSTROM, CO, HAUENSTEINN, F, HEIJKENSKJOLD, L, HEJNY, V, HINTERBERGER, F, HODANA, M, HOISTAD, B, JANY, A, JANY, BR, JARCZYK, L, JOHANSSON, T, KAMYS, B, KEMMERLING, G, KHAN, FA, KHOUKAZ, A, KISTRYN, S, KLAJA, J, KLEINES, H, KIRILLOV, DA, KLOS, B, KRAPP, M, KRZEMIEN, W, KULESSA, P, KUPSC, A, KUZMIN, A, LALWANI, K, LERSCH, D, LI, L, LORENTZ, B, MAGIERA, A, MAIER, R, MARCINIEWSKI, P, MARIANSKI, B, MEISSNER, UG, MIKIRTYCHIANTS, M, MORSCH, HP, MOSKAL, P, NANDI, BK, OHM, H, OZERIANSKA, I, DEL RIO, EP, PISKUNOV, NM, PLUCINSKI, P, PODKOPAL, P, PRASUHN, D, PRICKING, A, PSZCZEL, D, PYSZ, K, PYSZNIAK, A, REDMER, CF, RITMAN, J, ROY, A, RUDY, Z, SAWANT, S, SCHADMAND, S, SCHMIDT, A, SEFZICK, T, SERDYUK, V, SHAH, N, SHWARTZ, B, SIEMASZKO, M, SIUDAK, R, SKORODKO, T, SKURZOK, M, SMYRSKI, J, SOPOV, V, STASSEN, R, STEPANIAK, J, STEPHAN, E, STERZENBACH, G, STOCKHORST, H, STROHER, H, SZCZUREK, A, TOLBA, T, TRZCINSKI, A, VARMA, R, WAGNER, GJ, WEGLORZ, W, WIRZBA, A, WOLKE, M, WRONSKA, A, WUSTNER, P, WURM, P, YAMAMOTO, A, ZABIEROWSKI, J, ZIELINSKI, MJ, ZIPPER, W, ZLOMANCZUK, J, ZUPRANSKI, P, and ZUREK, M
Subjects: Gauge Vector Boson, Dark Forces, Phi-Meson Decays, Vector Gauge Boson, Kloe Detector, Energies
Abstract: The presently world largest data sample for pi(0) -> gamma e(+)e(-) decays studies containing nearly 5 x 10(5) events was collected using the WASA detector at COSY. A search for a dark photon U produced in the pi(0) -> gamma U -> gamma e(+)e(-) decay from the pp -> pp pi(0) reaction was carried out. An upper limit on the square of the U -> gamma mixing strength parameter epsilon(2) of 5 x 10(-6) at 90% CL was obtained for the mass range 20 MeV < M-U < 100 MeV. This result together with other recent experimental limits significantly reduces the M-U vs. epsilon(2) parameter space which could explain the presently seen deviation between the Standard Model prediction and the direct measurement of the anomalous magnetic moment of the muon. (C) 2013 Elsevier B.V. All rights reserved.
Published: 2013
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20. Investigation of the dd -> (3)Hen pi(0) reaction with the FZ Julich WASA-at-COSY facility

Author: ADLARSON, P, AUGUSTYNIAK, W, BARDAN, W, BASHKANOV, M, BERGMANN, FS, BERLOWSKI, M, BHATT, H, BUSCHER, M, CALEN, H, CIEPAL, I, CLEMENT, H, CODERRE, D, CZERWINSKI, E, DEMMICH, K, DOROSHKEVICH, E, ENGELS, R, ERVEN, W, EYRICH, W, FEDORETS, P, FOHL, K, FRANSSON, K, GOLDENBAUM, F, GOSLAWSKI, P, GOSWAMI, A, GRIGORYEV, K, GULLSTROM, CO, HANHART, C, HAUENSTEIN, F, HEIJKENSKJOLD, L, HEJNY, V, HINTERBERGER, F, HODANA, M, HOISTAD, B, JANY, A, JANY, BR, JARCZYK, L, JOHANSSON, T, KAMYS, B, KEMMERLING, G, KHAN, FA, KHOUKAZ, A, KIRILLOV, DA, KISTRYN, S, KLAJA, J, KLEINES, H, KLOS, B, KRAPP, M, KRZEMIEN, W, KULESSA, P, KUPSC, A, LALWANI, K, LERSCH, D, LI, L, LORENTZ, B, MAGIERA, A, MAIER, R, MARCINIEWSKI, P, MARIANSKI, B, MIKIRTYCHIANTS, M, MORSCH, HP, MOSKAL, P, NANDI, BK, OHM, H, OZERIANSKA, I, DEL RIO, EP, PISKUNOV, NM, PLUCINSKI, P, PODKOPAL, P, PRASUHN, D, PRICKING, A, PSZCZEL, D, PYSZ, K, PYSZNIAK, A, REDMER, CF, RITMAN, J, ROY, A, RUDY, Z, SAWANT, S, SCHMIDT, A, SCHADMAND, S, SEFZICK, T, SERDYUK, V, SHAH, N, SIEMASZKO, M, SIUDAK, R, SKORODKO, T, SKURZOK, M, SMYRSKI, J, SOPOV, V, STASSEN, R, STEPANIAK, J, STEPHAN, E, STERZENBACH, G, STOCKHORST, H, STROHER, H, SZCZUREK, A, TOLBA, T, TRZCINSKI, A, VARMA, R, WAGNER, GJ, WEGLORZ, W, WOLKE, M, WRONSKA, A, WUSTNER, P, WURM, P, YAMAMOTO, A, YUAN, X, ZABIEROWSKI, J, ZHENG, C, ZIELINSKI, MJ, ZIPPER, W, ZLOMANCZUK, J, ZUPRANSKI, P, and ZUREK, M
Subjects: Threshold, Quark Masses
Abstract: An exclusive measurement of the dd -> (3)Hen pi(0) reaction was carried out at a beam momentum of p(d) = 1.2 GeV/c using the WASA-at-COSY facility. Information on the total cross section as well as differential distributions was obtained. The data are described by a phenomenological approach based on a combination of a quasifree model and a partial wave expansion for the three-body reaction. The total cross section is found to be sigma(tot) = ( 2.89 +/- 0.01(stat) +/- 0.06(sys) +/- 0.29(norm)) mu b. The contribution of the quasifree processes ( with the beam or target neutron being a spectator) accounts for 38% of the total cross section and dominates the differential distributions in specific regions of phase space. The remaining part of the cross section can be described by a partial wave decomposition indicating the significance of p-wave contributions in the final state.
Published: 2013
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21. Search for $\eta$-mesic ^{4}He with the WASA-at-COSY detector

Author: Adlarson, P., Augustyniak, W., Bardan, Wiktor, Bashkanov, M., Bednarski, Tomasz, Bergmann, F. S., Berłowski, M., Bhatt, H., Büscher, M., Calén, Hans, Clement, H., Coderre, D., Czerwiński, Eryk, Demmich, K., Doroshkevich, E., Engels, R., Erven, W., Eyrich, W., Fedorets, P., Föhl, K., Fransson, K., Goldenbaum, F., Goslawski, P., Goswami, A., Grigoryev, K., Gullström, C.-O., Hauenstein, F., Heijkenskjöld, L., Hejny, V., Hinterberger, F., Hodana, Małgorzata, Höistad, B., Jany, Anna, Jany, Benedykt, Jarczyk, Lucjan, Johansson, T., Kamys, Bogusław, Kemmerling, G., Khan, F. A., Khoukaz, A., Kistryn, Stanisław, Klaja, Joanna, Kleines, H., Kłos, B., Krapp, M., Krzemień, Wojciech, Kulessa, P., Kupść, A., Lalwani, K., Lersch, D., Li, L., Lorentz, B., Magiera, Andrzej, Maier, R., Marciniewski, P., Mariański, B., Mikirtychiants, M., Morsch, H.-P., Moskal, Paweł, Nandi, B. K., Niedźwiecki, Szymon, Ohm, H., Schätti - Ozerianska, Iryna, Perez del Rio, Elena, Pluciński, P., Podkopał, Paweł, Prasuhn, D., Pricking, A., Pszczel, D., Pysz, K., Pyszniak, Andrzej, Redmer, C. F., Ritman, J., Roy, A., Rudy, Zbigniew, Sawant, S., Schadmand, S., Schmidt, A., Sefzick, T., Serdyuk, V., Shah, N., Siemaszko, M., Siudak, R., Skorodko, T., Skurzok, Magdalena, Smyrski, Jerzy, Sopov, V., Stassen, R., Stepaniak, J., Stephan, E., Sterzenbach, G., Stockhorst, H., Ströher, H., Szczurek, A., Tolba, T., Trzciński, A., Varma, R., Vlasov, P., Wagner, G. J., Węglorz, W., Wolke, M., Wrońska, Aleksandra, Wüstner, P., Wurm, P., Yamamoto, A., Yuan, X., Yurev, L., Zabierowski, J., Zheng, C., Zieliński, Marcin, Zipper, W., Złomańczuk, J., Żuprański, P., and Żurek, M.
Published: 2013

22. Search for eta-mesic He-4 with the WASA-at-COSY detector

Author: ADLARSON, P, AUGUSTYNIAK, W, BARDAN, W, BASHKANOV, M, BEDNARSKI, T, BERGMANN, FS, BERLOWSKI, M, BHATT, H, BUSCHER, M, CALEN, H, CLEMENT, H, CODERRE, D, CZERWINSKI, E, DEMMICH, K, DOROSHKEVICH, E, ENGELS, R, ERVEN, W, EYRICH, W, FEDORETS, P, FOHL, K, FRANSSON, K, GOLDENBAUM, F, GOSLAWSKI, P, GOSWAMI, A, GRIGORYEV, K, GULLSTROM, CO, HAUENSTEIN, F, HEIJKENSKJOLD, L, HEJNY, V, HINTERBERGER, F, HODANA, M, HOISTAD, B, JANY, A, JANY, BR, JARCZYK, L, JOHANSSON, T, KAMYS, B, KEMMERLING, G, KHAN, FA, KHOUKAZ, A, KISTRYN, S, KLAJA, J, KLEINES, H, KLOS, B, KRAPP, M, KRZEMIEN, W, KULESSA, P, KUPSC, A, LALWANI, K, LERSCH, D, LI, L, LORENTZ, B, MAGIERA, A, MAIER, R, MARCINIEWSKI, P, MARIANSKI, B, MIKIRTYCHIANTS, M, MORSCH, HP, MOSKAL, P, NANDI, BK, NIEDZWIECKI, S, OHM, H, OZERIANSKA, I, DEL RIO, EP, PLUCINSKI, P, PODKOPAL, P, PRASUHN, D, PRICKING, A, PSZCZEL, D, PYSZ, K, PYSZNIAK, A, REDMER, CF, RITMAN, J, ROY, A, RUDY, Z, SAWANT, S, SCHADMAND, S, SCHMIDT, A, SEFZICK, T, SERDYUK, V, SHAH, N, SIEMASZKO, M, SIUDAK, R, SKORODKO, T, SKURZOK, M, SMYRSKI, J, SOPOV, V, STASSEN, R, STEPANIAK, J, STEPHAN, E, STERZENBACH, G, STOCKHORST, H, STROHER, H, SZCZUREK, A, TOLBA, T, TRZCINSKI, A, VARMA, R, VLASOV, P, WAGNER, GJ, WEGLORZ, W, WOLKE, M, WRONSKA, A, WUSTNER, P, WURM, P, YAMAMOTO, A, YUAN, X, YUREV, L, ZABIEROWSKI, J, ZHENG, C, ZIELINSKI, MJ, ZIPPER, W, ZLOMANCZUK, J, ZUPRANSKI, P, and ZUREK, M
Subjects: Photoproduction, Mesons, Bound-States, Nuclei
Abstract: An exclusive measurement of the excitation function for the dd -> (3)Hep pi(-) reaction was performed at the Cooler Synchrotron COSY-Julich with the WASA-at-COSY detection system. The data were taken during a slow acceleration of the beam from 2.185 to 2.400 GeV/c crossing the kinematic threshold for the eta-meson production in the dd -> He-4 eta reaction at 2.336 GeV/c. The corresponding excess energy with respect to the He-4-eta system varied from -51.4 to 22 MeV. The integrated luminosity in the experiment was determined using the dd -> (3)Hen reaction. The shape of the excitation function for the dd -> (3)Hep pi(-) reaction was examined. No signal of the He-4-eta bound state was observed. An upper limit for the cross section for the bound state formation and decay in the process dd -> (He-4-eta)(bound) -> (3)Hep pi(-) was determined on the 90% confidence level and it varies from 20 to 27 nb for the bound state width ranging from 5 to 35 MeV, respectively. DOI: 10.1103/PhysRevC.87.035204
Published: 2013

23. Search for the eta-mesic 4He with WASA-at-COSY detector

Author: Adlarson, P., Augustyniak, W., Bardan, W., Bashkanov, M., Bednarski, T., Bergmann, F. S., Berlowski, M., Bhatt, H., Buescher, M., Calen, H., Clement, H., Coderre, D., Czerwinski, E., Demmich, K., Doroshkevich, E., Engels, R., Erven, W., Eyrich, W., Fedorets, P., Foehl, K., Fransson, K., Goldenbaum, F., Goslawski, P., Goswami, A., Grigoryev, K., Gullstroem, C. -O., Hauenstein, F., Heijkenskjoeld, L., Hejny, V., Hinterberger, F., Hodana, M., Hoeistad, B., Jany, A., Jany, B. R., Jarczyk, L., Johansson, T., Kamys, B., Kemmerling, G., Khan, F. A., Khoukaz, A., Kistryn, S., Klaja, J., Kleines, H., Klos, B., Krapp, M., Krzemien, W., Kulessa, P., Kupsc, A., Lalwani, K., Lersch, D., Li, L., Lorentz, B., Magiera, A., Maier, R., Marciniewski, P., Marianski, B., Mikirtychiants, M., Morsch, H. -P., Moskal, P., Nandi, B. K., Niedzwiecki, S., Ohm, H., Ozerianska, I., del Rio, E. Perez, Plucinski, P., Podkopal, P., Prasuhn, D., Pricking, A., Pszczel, D., Pysz, K., Pyszniak, A., Redmer, C. F., Ritman, J., Roy, A., Rudy, Z., Sawant, S., Schadmand, S., Schmidt, A., Sefzick, T., Serdyuk, V., Shah, N., Siemaszko, M., Siudak, R., Skorodko, T., Skurzok, M., Smyrski, J., Sopov, V., Stassen, R., Stepaniak, J., Stephan, E., Sterzenbach, G., Stockhorst, H., Stroeher, H., Szczurek, A., Tolba, T., Trzcinski, A., Varma, R., Vlasov, P., Wagner, G. J., Weglorz, W., Wolke, M., Wronska, A., Wuestner, P., Wurm, P., Yamamoto, A., Yuan, X., Yurev, L., Zabierowski, J., Zheng, C., Zielinski, M. J., Zipper, W., Zlomanczuk, J., Zupranski, P., and Zurek, M.
Subjects: FOS: Physical sciences, High Energy Physics::Experiment, Nuclear Experiment (nucl-ex), Nuclear Experiment
Abstract: An exclusive measurement of the excitation function for the dd->3Heppi- reaction was performed at the Cooler Synchrotron COSY-Juelich with the WASA-at-COSY detection system. The data were taken during a slow acceleration of the beam from 2.185 GeV/c to 2.400 GeV/c crossing the kinematic threshold for the eta meson production in the dd->4He-eta reaction at 2.336 GeV/c. The corresponding excess energy with respect to the 4He-eta system varied from -51.4MeV to 22MeV. The integrated luminosity in the experiment was determined using the dd->3Hen reaction. The shape of the excitation function for the dd->3Heppi- was examined. No signal of the 4He-eta bound state was observed. An upper limit for the cross-section for the bound state formation and decay in the process dd->(4He-eta)bound->3Heppi- was determined on the 90% confidence level and it varies from 20nb to 27nb for the bound state width ranging from 5MeV to 35MeV, respectively., 8 pages, 9 figures
Published: 2013
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24. Measurement of the $pn \to pp��^0��^-$ Reaction in Search for the Recently Observed Resonance Structure in $d��^0��^0$ and $d��^+��^-$ systems

Author: Adlarson, P., Augustyniak, W., Bardan, W., Bashkanov, M., Bergmann, F. S., Ber��owski, M., Bhatt, H., B��scher, M., Cal��n, H., Ciepa��, I., Clement, H., Coderre, D., Czerwi��ski, E., Demmich, K., Doroshkevich, E., Engels, R., Erven, W., Eyrich, W., Fedorets, P., F��hl, K., Fransson, K., Goldenbaum, F., Goslawski, P., Goswami, A., Grigoryev, K., Gullstr��m, C. --O., Hauenstein, F., Heijkenskj��ld, L., Hejny, V., Hinterberger, F., Hodana, M., H��istad, B., Jany, A., Jany, B. R., Jarczyk, L., Johansson, T., Kamys, B., Kemmerling, G., Khan, F. A., Khoukaz, A., Kirillov, D. A., Kistryn, S., Klaja, J., Kleines, H., K��os, B., Krapp, M., Krzemie��, W., Kulessa, P., Kup��, A., Lalwani, K., Lersch, D., Li, L., Lorentz, B., Magiera, A., Maier, R., Marciniewski, P., Maria��ski, B., Mikirtychiants, M., Morsch, H. --P., Moskal, P., Nandi, B. K., Ohm, H., Ozerianska, I., del Rio, E. Perez, Piskunov, N. M., Pluci��ski, P., Podkopa��, P., Prasuhn, D., Pricking, A., Pszczel, D., Pysz, K., Pyszniak, A., Redmer, C. F., Ritman, J., Roy, A., Rudy, Z., Sawant, S., Schmidt, A., Schadmand, S., Sefzick, T., Serdyuk, V., Shah, N., Siemaszko, M., Siudak, R., Skorodko, T., Skurzok, M., Smyrski, J., Sopov, V., Stassen, R., Stepaniak, J., Stephan, E., Sterzenbach, G., Stockhorst, H., Str��her, H., Szczurek, A., Tolba, T., Trzci��ski, A., Varma, R., Wagner, G. J., W��glorz, W., Wolke, M., Wro��ska, A., W��stner, P., Wurm, P., Yamamoto, A., Yuan, X., Zabierowski, J., Zheng, C., Zieli��ski, M. J., Zipper, W., Z��oma��czuk, J., ��upra��ski, P., and ��urek, M.
Subjects: FOS: Physical sciences, Nuclear Experiment (nucl-ex), Nuclear Experiment
Abstract: Exclusive measurements of the quasi-free $pn \to pp��^0��^-$ reaction have been performed by means of $pd$ collisions at $T_p$ = 1.2 GeV using the WASA detector setup at COSY. Total and differential cross sections have been obtained covering the energy region $\sqrt s$ = (2.35 - 2.46) GeV, which includes the region of the ABC effect and its associated resonance structure. No ABC effect, {\it i.e.} low-mass enhancement is found in the $��^0��^-$-invariant mass spectrum -- in agreement with the constraint from Bose statistics that the isovector pion pair can not be in relative s-wave. At the upper end of the covered energy region $t$-channel processes for Roper, $��(1600)$ and $��$ excitations provide a reasonable description of the data, but at low energies the measured cross sections are much larger than predicted by such processes. Adding a resonance amplitude for the resonance at $m$=~2.37 GeV with $��$ =~70 MeV and $I(J^P)=~0(3^+)$ observed recently in $pn \to d��^0��^0$ and $pn \to d��^+��^-$ reactions leads to an agreement with the data also at low energies.
Published: 2013
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25. Final-State Interactions in the Process pp -> pKLambda

Author: R��der, M., Borodina, E., Clement, H., Doroshkevich, E., Dzhygadlo, R., Ehrhardt, K., Erhardt, A., Eyrich, W., Gast, W., Gillitzer, A., Grzonka, D., Haidenbauer, J., Hanhart, C., Hauenstein, F., Klaja, P., Kober, L., Kilian, K., Krapp, M., Mertens, M., Ritman, J., Roderburg, E., Schroeder, W., Sefzick, T., Sibirtsev, A., Wintz, P., and W��stner, P.
Subjects: FOS: Physical sciences, Nuclear Experiment (nucl-ex)
Abstract: The possibility to determine the pLambda scattering length from the final-state interaction in the reaction pp->pKLambda is investigated experimentally. From a transversely polarized measurement, the K analyzing power (A_N) which, in principle, allows one to extract the spin triplet scattering length is studied. An unexpected energy dependence of the forward/backward symmetric part of A_N is found. The influence of N*-resonances on the pLambda invariant mass spectrum is investigated by exploiting the large acceptance for the process pp->pKLambda->pKppi and is found to be the main source of uncertainty for determining the pLambda scattering length.
Published: 2013
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26. Search for a dark photon in the $\pi ^{0}\rightarrow e^{+}e^{-}\gamma$ decay

Author: Adlarson, P., Augustyniak, W., Bardan, Wiktor, Bashkanov, M., Berłowski, M., Bhatt, H., Bondar, A., Calén, Hans, Ciepał, Izabela, Clement, H., Coderre, D., Czerwiński, Eryk, Demmich, K., Doroshkevich, E., Engels, R., Erven, W., Eyrich, W., Fedorets, P., Föhl, K., Goldenbaum, E., Goslawski, P., Goswami, A., Gullström, C.-O., Hauenstein, F., Hejny, V., Hinterberger, F., Hodana, Małgorzata, Jany, Anna, Jany, Benedykt, Jarczyk, Lucjan, Johansson, T., Kamys, Bogusław, Kemmerling, G., Khan, F. A., Khoukaz, A., Klaja, Joanna, Kleines, H., Kirillov, D. A., Kłos, B., Krapp, M., Krzemień, Wojciech, Kulessa, P., Kupść, A., Lalwani, K., Lersch, D., Li, L., Lorentz, B., Maier, R., Marciniewski, P., Mariański, B., Mikirtychiants, M., Morsch, H.-P., Moskal, Paweł, Nandi, B. K., Ohm, H., Schätti - Ozerianska, Iryna, Perez del Rio, Elena, Pluciński, P., Podkopał, Paweł, Prasuhn, D., Pszczel, D., Pysz, K., Pyszniak, Andrzej, Ritman, J., Roy, A., Rudy, Zbigniew, Sawant, S., Schmidt, A., Sefzick, T., Serdyuk, V., Shah, N., Shwartz, B., Siemaszko, M., Siudak, R., Skorodko, T., Smyrski, Jerzy, Sopov, V., Stassen, R., Stepaniak, J., Stephan, E., Sterzenbach, G., Stockhorst, H., Ströher, H., Szczurek, A., Tolba, T., Trzciński, A., Varma, R., Węglorz, W., Wirzba, A., Wolke, M., Wrońska, Aleksandra, Wüstner, P., Wurm, P., Yamamoto, A., Zabierowski, J., Zipper, W., Złomańczuk, J., Żuprański, P., Bergmann, F. S., Büscher, M., Fransson, K., Grigoryev, K., Heijkenskjöld, L., Höistad, B., Kistryn, Stanisław, Kuzmin, A., Magiera, Andrzej, Meißner, U.-G., Piskunov, N. M., Pricking, A., Redmer, C. F., Schadmand, S., Wagner, G. J., Skurzok, Magdalena, Zieliński, Marcin, and Żurek, M.
Subjects: dark forces, gauge vector boson
Published: 2013

27. Investigation of the dd\rightarrow $^{3}Hen\pi ^{0}$ reaction with the FZ Jülich WASA-at-COSY facility

Author: Adlarson, P., Augustyniak, W., Bardan, Wiktor, Bashkanov, M., Berłowski, M., Bhatt, H., Büscher, M., Ciepał, Izabela, Clement, H., Coderre, D., Czerwiński, Eryk, Demmich, K., Doroshkevich, E., Engels, R., Erven, W., Fedorets, P., Föhl, K., Fransson, K., Goslawski, P., Goswami, A., Grigoryev, K., Hanhart, C., Hauenstein, F., Heijkenskjöld, L., Hejny, V., Hinterberger, F., Hodana, M., Höistad, B., Jany, Benedykt, Jarczyk, Lucjan, Johansson, T., Kamys, Bogusław, Khan, F. A., Khoukaz, A., Kirillov, D. A., Klaja, Joanna, Kleines, H., Kłos, B., Krapp, M., Kulessa, P., Kupść, A., Lalwani, K., Li, L., Lorentz, B., Magiera, Andrzej, Maier, R., Mariański, B., Mikirtychiants, M., Morsch, H.-P., Moskal, Paweł, Nandi, B. K., Ohm, H., Schätti - Ozerianska, Iryna, Piskunov, N. M., Pluciński, P., Podkopał, Paweł, Pricking, A., Pszczel, D., Pysz, K., Redmer, C. F., Ritman, J., Roy, A., Rudy, Zbigniew, Schmidt, A., Schadmand, S., Sefzick, T., Shah, N., Siemaszko, M., Siudak, R., Skorodko, T., Skurzok, Magdalena, Smyrski, Jerzy, Sopov, V., Stassen, R., Stephan, E., Sterzenbach, G., Stockhorst, H., Szczurek, A., Tolba, T., Trzciński, A., Varma,R., Wagner, G. J., Węglorz, W., Wolke, M., Wrońska, Aleksandra, Wurm, P., Yamamoto, A., Yuan, X., Zabierowski,J., Zheng, C., Zieliński, Marcin, Zipper, W., Złomańczuk, J., Żurek, M., Bergmann, F. S., Calén, Hans, Goldenbaum, F., Eyrich, W., Gullström, C.-O., Jany, Anna, Kemmerling, G., Kistryn, Stanisław, Krzemień, Wojciech, Lersch, D., Marciniewski, P., Perez del Rio, Elena, Prasuhn, D., Pyszniak, Andrzej, Sawant, S., Serdyuk, V., Stepaniak, J., Ströher, H., Wüstner, P., and Żuprański, P.
Abstract: An exclusive measurement of the dd\rightarrow $^{3}Hen\pi^{0}$ eaction was carried out at a beam momentum of $p_{d}$=1.2 GeV/c using the WASA-at-COSY facility. Information on the total cross section as well as differential distributions was obtained. The data are described by a phenomenological approach based on a combination of a quasifree model and a partial wave expansion for the three-body reaction. The total cross section is found to be $\sigma _{tot}= \left ( 2.89\pm 0.01_{stat}\pm 0.06_{sys}\pm 0.29_{norm} \right )\mu b$. The contribution of the quasifree processes (with the beam or target neutron being a spectator) accounts for 38% of the total cross section and dominates the differential distributions in specific regions of phase space. The remaining part of the cross section can be described by a partial wave decomposition indicating the significance of p-wave contributions in the final state.
Published: 2013

28. Measurement of the pn→ppπ0π− reaction in search for the recently observed resonance structure in dπ0π0 and dπ+π− systems

Author: Adlarson, P., Augustyniak, W., Clement, H., Wolke, M., Wrońska, A., Wüstner, P., Wurm, P., Yamamoto, A., Yuan, X., Zabierowski, J., Zheng, C., Zieliński, M. J., Zipper, W., Coderre, D., Złomańczuk, J., Żuprański, P., Żurek, M., Czerwiński, E., Demmich, K., Doroshkevich, E., Engels, R., Erven, W., Eyrich, W., Fedorets, P., Föhl, K., Bardan, W., Fransson, K., Goldenbaum, F., Goslawski, P., Goswami, A., Grigoryev, K., Gullström, C. -O., Hauenstein, F., Heijkenskjöld, L., Hejny, V., Hinterberger, F., Bashkanov, M., Hodana, M., Höistad, B., Jany, A., Jany, B. R., Jarczyk, L., Johansson, T., Kamys, B., Kemmerling, Günter, Khan, F. A., Khoukaz, A., Bergmann, F. S., Kirillov, D. A., Kistryn, S., Klaja, J., Kleines, H., Kłos, B., Krapp, M., Krzemień, W., Kulessa, P., Kupść, A., Lalwani, K., Berłowski, M., Lersch, D., Li, L., Lorentz, B., Magiera, A., Maier, R., Marciniewski, P., Mariański, B., Mikirtychiants, M., Morsch, H. -P., Moskal, P., Bhatt, H., Nandi, B. K., Ohm, H., Ozerianska, I., Perez del Rio, E., Piskunov, N. M., Pluciński, P., Podkopał, P., Prasuhn, D., Pricking, A., Pszczel, D., Büscher, M., Pysz, K., Pyszniak, A., Redmer, C. F., Ritman, J., Roy, A., Rudy, Z., Sawant, S., Schmidt, A., Schadmand, S., Sefzick, T., Calen, Hans, Serdyuk, V., Shah, N., Siemaszko, M., Siudak, R., Skorodko, T., Skurzok, M., Smyrski, J., Sopov, V., Stassen, R., Stepaniak, J., Ciepał, I., Stephan, E., Sterzenbach, G., Stockhorst, H., Ströher, H., Szczurek, A., Tolba, T., Trzciński, A., Varma, R., Wagner, G. J., and Węglorz, W.
Subjects: effective Lagrangian, Nuclear Theory, polarized beam [photon], amplitude analysis, exclusive reaction [photon nucleon], associated production [omega(783)], threshold, ddc:530, momentum transfer [differential cross section], +N%281440%29+omega%28783%29%22">photon nucleon --> N(1440) omega(783), photoproduction [N(1440)], Nuclear Experiment, asymmetry [spin], numerical calculations
Abstract: Associative photoproduction of $\omega$-meson and $N^{*}(1440)$ on nucleons, $\gamma+N\to\omega+N^{*}(1440)$, in the near threshold region is investigated in a framework employing effective Lagrangians. Besides $\pi$-exchange in t-channel, baryon exchanges, i.e. N- and $N^{*}$-exchanges, in the s- and u-channels are also taken into account in calculations of differential cross-section and beam asymmetry. Important inputs of this model are the vector and tensor coupling constants of $\omega NN^{*}(1440)$-vertex, which are assumed to be equal to the values of these couplings for $\omega NN$ vertex. Using our previous estimation of $\omega NN$ coupling constants obtained from a fit to available experimental data on photoproduction of $\omega$ meson in the near threshold region, we produce the necessary numerical predictions for different observables in $\gamma+N\to\omega+N^{*}(1440)$. Numerical results shows that at low $|$t$|$ dominant contribution comes from t-channel $\pi$-exchange while effects of nucleon and $N^{*}(1440)$ pole terms can be seen at large $|t|$. Our predictions for the differential cross section and beam asymmetry for the processes $\gamma+N\to\omega+N^{*}(1440)$, where N is proton and neutron at $E_{\gamma}=2.5$ GeV are presented with zero width approximation and also with the inclusion of width effects of $N^{*}(1440)$.
Published: 2013
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29. Investigation of the dd -> 3He n ��0 reaction with the FZ J��lich WASA-at-COSY facility

Author: COSY Collaboration, Adlarson, P., Augustyniak, W., Bardan, W., Bashkanov, M., Bergmann, F. S., Ber��owski, M., Bhatt, H., B��scher, M., Cal��n, H., Ciepa��, I., Clement, H., Coderre, D., Czerwi��ski, E., Demmich, K., Doroshkevich, E., Engels, R., Erven, W., Eyrich, W., Fedorets, P., F��hl, K., Fransson, K., Goldenbaum, F., Goslawski, P., Goswami, A., Grigoryev, K., Gullstr��m, C. --O., Hanhart, C., Hauenstein, F., Heijkenskj��ld, L., Hejny, V., Hinterberger, F., Hodana, M., H��istad, B., Jany, A., Jany, B. R., Jarczyk, L., Johansson, T., Kamys, B., Kemmerling, G., Khan, F. A., Khoukaz, A., Kirillov, D. A., Kistryn, S., Klaja, J., Kleines, H., K��os, B., Krapp, M., Krzemie��, W., Kulessa, P., Kup��, A., Lalwani, K., Lersch, D., Li, L., Lorentz, B., Magiera, A., Maier, R., Marciniewski, P., Maria��ski, B., Mikirtychiants, M., Morsch, H. --P., Moskal, P., Nandi, B. K., Ohm, H., Ozerianska, I., del Rio, E. Perez, Piskunov, N. M., Pluci��ski, P., Podkopa��, P., Prasuhn, D., Pricking, A., Pszczel, D., Pysz, K., Pyszniak, A., Redmer, C. F., Ritman, J., Roy, A., Rudy, Z., Sawant, S., Schmidt, A., Schadmand, S., Sefzick, T., Serdyuk, V., Shah, N., Siemaszko, M., Siudak, R., Skorodko, T., Skurzok, M., Smyrski, J., Sopov, V., Stassen, R., Stepaniak, J., Stephan, E., Sterzenbach, G., Stockhorst, H., Str��her, H., Szczurek, A., Tolba, T., Trzci��ski, A., Varma, R., Wagner, G. J., W��glorz, W., Wolke, M., Wro��ska, A., W��stner, P., Wurm, P., Yamamoto, A., Yuan, X., Zabierowski, J., Zheng, C., Zieli��ski, M. J., Zipper, W., Z��oma��czuk, J., ��upra��ski, P., and ��urek, M.
Subjects: FOS: Physical sciences, Nuclear Experiment (nucl-ex)
Abstract: An exclusive measurement of the dd -> 3He n ��0 reaction was carried at a beam momentum of p = 1.2 GeV/c using the WASA-at-COSY facility. For the first time data on the total cross section as well as differential distributions were obtained. The data are described with a phenomenological approach based on a combination of a quasi-free model and a partial wave expansion for three-body reaction. The total cross section is found to be ��(tot) = (2.89 +- 0.01(stat) +- 0.06(sys) +- 0.29(norm)) ��b. The contribution of the quasi-free processes (with the neutron being target or beam spectator) accounts for 38% of the total cross section and dominates the differential distributions in specific regions of the phase space. The remaining part of the cross section can be described within a partial wave decomposition indicating the significance of p-wave contributions in the final state., 9 pages, 7 figures
Published: 2013
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30. Search for η-mesic ^{4}He with the WASA-at-COSY detector

Author: Adlarson, P., Augustyniak, W., Clement, H., Wüstner, P., Wurm, P., Yamamoto, A., Yuan, X., Yurev, L., Zabierowski, J., Zheng, C., Zieliński, M. J., Zipper, W., Złomańczuk, J., Coderre, D., Żuprański, P., Żurek, M., Engels, Ralf W., Stroeher, Hans, Czerwiński, E., Demmich, K., Doroshkevich, E., Erven, W., Eyrich, W., Fedorets, P., Föhl, K., Fransson, K., Bardan, W., Goldenbaum, F., Goslawski, P., Goswami, A., Grigoryev, K., Gullström, C. –O., Hauenstein, F., Heijkenskjöld, L., Hejny, V., Hinterberger, F., Hodana, M., Bashkanov, M., Höistad, B., Jany, A., Jany, B. R., Jarczyk, L., Johansson, T., Kamys, B., Kemmerling, G., Khan, F. A., Khoukaz, A., Kistryn, S., Bednarski, T., Klaja, J., Kleines, H., Kłos, B., Krapp, M., Krzemień, W., Kulessa, P., Kupść, A., Lalwani, K., Lersch, D., Li, L., Bergmann, F. S., Lorentz, B., Magiera, A., Maier, R., Marciniewski, P., Mariański, B., Mikirtychiants, M., Morsch, H. –P., Moskal, P., Nandi, B. K., Niedźwiecki, S., Berłowski, M., Ohm, H., Ozerianska, I., Perez del Rio, E., Pluciński, P., Podkopał, P., Prasuhn, D., Pricking, A., Pszczel, D., Pysz, K., Pyszniak, A., Bhatt, H., Redmer, C. F., Ritman, J., Roy, A., Rudy, Z., Sawant, S., Schadmand, S., Schmidt, A., Sefzick, T., Serdyuk, V., Shah, N., Büscher, M., Siemaszko, M., Siudak, R., Skorodko, T., Skurzok, M., Smyrski, J., Sopov, V., Stassen, R., Stepaniak, J., Stephan, E., Sterzenbach, G., Calén, H., Stockhorst, H., Szczurek, A., Tolba, T., Trzciński, A., Varma, R., Vlasov, P., Wagner, G. J., Węglorz, W., Wolke, M., and Wrońska, A.
Subjects: High Energy Physics::Experiment, ddc:530, Nuclear Experiment
Abstract: An exclusive measurement of the excitation function for the dd->3Heppi- reaction was performed at the Cooler Synchrotron COSY-Juelich with the WASA-at-COSY detection system. The data were taken during a slow acceleration of the beam from 2.185 GeV/c to 2.400 GeV/c crossing the kinematic threshold for the eta meson production in the dd->4He-eta reaction at 2.336 GeV/c. The corresponding excess energy with respect to the 4He-eta system varied from -51.4MeV to 22MeV. The integrated luminosity in the experiment was determined using the dd->3Hen reaction. The shape of the excitation function for the dd->3Heppi- was examined. No signal of the 4He-eta bound state was observed. An upper limit for the cross-section for the bound state formation and decay in the process dd->(4He-eta)bound->3Heppi- was determined on the 90% confidence level and it varies from 20nb to 27nb for the bound state width ranging from 5MeV to 35MeV, respectively.
Published: 2013
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31. Measurement of the pn -> pp pi(0)pi(-) reaction in search for the recently observed resonance structure in d pi(0)pi(0) and d pi(+)pi(-) systems

Author: ADLARSON, P, AUGUSTYNIAK, W, BARDAN, W, BASHKANOV, M, BERGMANN, FS, BERLOWSKI, M, BHATT, H, BUSCHER, M, CALEN, H, CIEPAL, I, CLEMENT, H, CODERRE, D, CZERWINSKI, E, DEMMICH, K, DOROSHKEVICH, E, ENGELS, R, ERVEN, W, EYRICH, W, FEDORETS, P, FOHL, K, FRANSSON, K, GOLDENBAUM, F, GOSLAWSKI, P, GOSWAMI, A, GRIGORYEV, K, GULLSTROM, CO, HAUENSTEIN, F, HEIJKENSKJOLD, L, HEJNY, V, HINTERBERGER, F, HODANA, M, HOISTAD, B, JANY, A, JANY, BR, JARCZYK, L, JOHANSSON, T, KAMYS, B, KEMMERLING, G, KHAN, FA, KHOUKAZ, A, KIRILLOV, DA, KISTRYN, S, KLAJA, J, KLEINES, H, KLOS, B, KRAPP, M, KRZEMIEN, W, KULESSA, P, KUPSC, A, LALWANI, K, LERSCH, D, LI, L, LORENTZ, B, MAGIERA, A, MAIER, R, MARCINIEWSKI, P, MARIANSKI, B, MIKIRTYCHIANTS, M, MORSCH, HP, MOSKAL, P, NANDI, BK, OHM, H, OZERIANSKA, I, DEL RIO, EP, PISKUNOV, NM, PLUCINSKI, P, PODKOPAL, P, PRASUHN, D, PRICKING, A, PSZCZEL, D, PYSZ, K, PYSZNIAK, A, REDMER, CF, RITMAN, J, ROY, A, RUDY, Z, SAWANT, S, SCHMIDT, A, SCHADMAND, S, SEFZICK, T, SERDYUK, V, SHAH, N, SIEMASZKO, M, SIUDAK, R, SKORODKO, T, SKURZOK, M, SMYRSKI, J, SOPOV, V, STASSEN, R, STEPANIAK, J, STEPHAN, E, STERZENBACH, G, STOCKHORST, H, STROHER, H, SZCZUREK, A, TOLBA, T, TRZCINSKI, A, VARMA, R, WAGNER, GJ, EGLORZ, WW, WOLKE, M, WRONSKA, A, WUSTNER, P, WURM, P, YAMAMOTO, A, YUAN, X, ZABIEROWSKI, J, ZHENG, C, ZIELINSKI, MJ, ZIPPER, W, ZLOMANCZUK, J, ZUPRANSKI, P, and ZUREK, M
Subjects: Roper Resonance, Proton-Proton Collisions, Gev/C, Nucleon-Nucleon Collisions, Pi(0)Pi(0) Production, Meson Production, Double-Pion Production, Cross-Sections, Isospin Decomposition, Excitation
Abstract: Exclusive measurements of the quasifree pn -> pp pi(0)pi(-) reaction have been performed by means of pd collisions at T-p = 1.2 GeV using the wide angle shower apparatus (WASA) detector setup at the cooler synchrotron COSY (Institut fur Kernphysik, Julich). Total and differential cross sections have been obtained covering the energy region root s = (2.35-2.46) GeV, which includes the region of the ABC effect and its associated resonance structure. NoABCeffect, i.e., low-mass enhancement is found in the pi(0)pi(-) -invariant mass spectrum, in agreement with the constraint from Bose statistics that the isovector pion pair can not be in relative s wave. At the upper end of the covered energy region t-channel processes for Roper, Delta(1600) and Delta Delta excitations provide a reasonable description of the data, but at low energies the measured cross sections are much larger than predicted by such processes. Adding a resonance amplitude for the resonance at m = 2.37 GeV with Gamma = 70 MeV and I (J(P)) = 0(3(+)) observed recently in pn -> d pi(0)pi(0) and pn -> d pi(+)pi(-) reactions leads to an agreement with the data also at low energies.
Published: 2013
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32. Measurement of the $pn \rightarrow pp\pi ^{0}\pi ^{-}$ reaction in search for the recently observed resonance structure in $d\pi ^{0}\pi ^{0}$ and $d\pi ^{+}\pi ^{-}$ systems

Author: Adlarson, P., Augustyniak, W., Bardan, Wiktor, Bashkanov, M., Bergmann, F. S., Berłowski, M., Bhatt, H., Büscher, M., Calén, H., Ciepał, Izabela, Clement, H., Coderre, D., Czerwiński, Eryk, Demmich, K., Doroshkevich, E., Engels, R., Erven, W., Eyrich, W., Fedorets, P., Föhl, K., Fransson, K., Goldenbaum, F., Goslawski, P., Goswami, A., Grigoryev, K., Gullström, C.-O., Hauenstein, F., Heijkenskjöld, L., Hejny, V., Hinterberger, F., Hodana, Małgorzata, Höistad, B., Jany, Anna, Jany, Benedykt, Jarczyk, Lucjan, Johansson, T., Kamys, Bogusław, Kemmerling, G., Khan, F. A., Khoukaz, A., Kirillov, D. A., Kistryn, Stanisław, Klaja, Joanna, Kleines, H., Kłos, B., Krapp, M., Krzemień, Wojciech, Kulessa, P., Kupść, A., Lalwani, K., Lersch, D., Li, L., Lorentz, B., Magiera, Andrzej, Maier, R., Marciniewski, P., Mariański, B., Mikirtychiants, M., Morsch, H.-P., Moskal, Paweł, Nandi, B. K., Ohm, H., Schätti - Ozerianska, Iryna, Perez del Rio, Elena, Piskunov, N. M., Pluciński, P., Podkopał, Paweł, Prasuhn, D., Pricking, A., Pszczel, D., Pysz, K., Pyszniak, Andrzej, Redmer, C. F., Ritman, J., Roy, A., Rudy, Zbigniew, Sawant, S., Schmidt, A., Schadmand, S., Sefzick, T., Serdyuk, V., Shah, N., Siemaszko, M., Siudak, R., Skorodko, T., Skurzok, Magdalena, Smyrski, Jerzy, Sopov, V., Stassen, R., Stepaniak, J., Stephan, E., Sterzenbach, G., Stockhorst, H., Ströher, H., Szczurek, A., Tolba, T., Trzciński, A., Varma, R., Wagner, G. J., Węglorz, W., Wolke, M., Wrońska, Aleksandra, Wüstner, P., Wurm, P., Yamamoto, A., Yuan, X., Zabierowski, J., Zheng, C., Zieliński, Marcin, Zipper, W., Złomańczuk, J., Żuprański, P., and Żurek, M.
Subjects: Nuclear Experiment
Abstract: Exclusive measurements of the quasifree $pn\rightarrow pp\pi ^{0}\pi ^{-}$ reaction have been performed by means of pd collisions at $T_{p}$= 1.2 GeV using the wide angle shower apparatus (WASA) detector setup at the cooler synchrotron COSY (Institut für Kernphysik, Jülich). Total and differential cross sections have been obtained covering the energy region $\sqrt{8}=\left ( 2.35-2.46 \right )$ GeV, which includes the region of the ABC effect and its associated resonance structure. No ABC effect, i.e., low-mass enhancement is found in the $\pi ^{0}\pi ^{-}$ -invariant mass spectrum, in agreement with the constraint from Bose statistics that the isovector pion pair can not be in relative s wave. At the upper end of the covered energy region t-channel processes for Roper, $\Delta \left ( 1600 \right )$ and $\Delta \Delta$ excitations provide a reasonable description of the data, but at low energies the measured cross sections are much larger than predicted by such processes. Adding a resonance amplitude for the resonance at m=2.37 GeV with $\Gamma$ =70 MeV and $I\left ( J^{P} \right )=0\left ( 3^{+} \right )$ observed recently in $pn\rightarrow d\pi ^{0}\pi ^{0}$ and $pn\rightarrow d\pi ^{+}\pi ^{-}$ reactions leads to an agreement with the data also at low energies.
Published: 2013

33. On the SigmaN cusp in the pp -> pK+Lambda reaction

Author: El-Samad, S. Abd, Borodina, E., Brinkmann, K. -Th., Clement, H., Doroshkevich, E., Dzhygadlo, R., Ehrhardt, K., Erhardt, A., Eyrich, W., Freiesleben, H., Gast, W., Gillitzer, A., Grzonka, D., Hanhart, C., Hauenstein, F., Klja, P., Kilian, K., Krapp, M., Ritman, J., Roderburg, E., Roeder, M., Schulte-Wissermann, M., Schroeder, W., Sfzick, T., Wagner, G. J., Wintz, P., and Wuestner, P.
Subjects: Nuclear Experiment, High Energy Physics - Experiment
Abstract: Measurements of the $pp \to pK^+\Lambda$ reaction at $T_p$ = 2.28 GeV have been carried out at COSY-TOF. In addition to the $\Lambda p$ FSI and $N^*$ resonance excitation effects a pronounced narrow structure is observed in the Dalitz plot and in its projection on the $p\Lambda$-invariant mass. The structure appears at the $pp \to $N$K^+\Sigma$ threshold and is interpreted as $\Sigma$N cusp effect. The observed width of 20 MeV/$c^2$ is substantially broader than anticipated from previous inclusive measurements. Angular distributions of this cusp structure are shown to be dissimilar to those in the residual $pK^+\Lambda$ channel, but similar to those observed in the $pK^+\Sigma^0$ channel.
Published: 2012

34. The pK0Σ+ final state in proton-proton collisions

Author: Collaboration, COSY-TOF, Abdel-Bary, M., Abdel-Samad, S., Brinkmann, K-Th., Clement, H., Dietrich, J., Doroshkevich, E., Dshemuchadse, S., Ehrhardt, K., Erhardt, A., Eyrich, W., Filippi, A., Freiesleben, H., Fritsch, M., Gast, W., Georgi, J., Gillitzer, A., Gottwald, J., Hesselbarth, D., Jäger, H., Jakob, B., Jäkel, R., Karsch, L., Kilian, K., Koch, H., Krapp, M., Kreß, J., Kuhlmann, E., Lehmann, A., Marcello, S., Marwinski, S., Mauro, S., Meyer, W., Michel, P., Möller, K., Morsch, H. P., Mörtel, H., Naumann, L., Paul, N., Pinna, L., Pizzolotto, C., Plettner, Ch., Reimann, S., Richter, M., Ritman, J., Roderburg, E., Schamlott, A., Schönmeier, P., Schroeder, W., Schulte-Wissermann, M., Sefzick, T., Stinzing, F., Steinke, M., Sun, G. Y., Teufel, A., Ullrich, W., Wagner, G. J., Wagner, M., Wenzel, R., Wilms, A., Wintz, P., Wirthand, S., Wüstner, P., and Zupranski, P.
Subjects: Nuclear and High Energy Physics, Proton, Nuclear Theory, hadroproduction [K0], Dalitz plot, measured [channel cross section], Nucleon-nucleon interactions, Hyperon-Nucleon interactions, Total cross sections, associated production [Sigma+], Juelich COSY PS, momentum transfer dependence, Resonance (particle physics), Spectral line, energy dependence, mass spectrum, phase space, measured [differential cross section], Invariant mass, ddc:530, angular distribution, Nuclear Experiment, Physics, exclusive reaction [p p], Range (particle radiation), Sigma, (Sigma+ p K0) [final state], helicity, Helicity, 3.059: 3.200 GeV/c: |(((1)) [2.950], COSY-TOF, +Sigma%2B+p+K0%22">p p --> Sigma+ p K0, Atomic physics, intermediate state [nucleon resonance], Beam (structure), experimental results
Abstract: This paper reports results from a study of the reaction pp->pK0\Sigma+ at beam momenta of p_{beam} = 2950, 3059, and 3200 MeV/c (excess energies of \epsilon= 126, 161, and 206 MeV). Total cross sections were determined for all energies; a set of differential cross sections (Dalitz plots; invariant mass spectra of all two-body subsystems; angular distributions of all final state particles; distributions in helicity and Jackson frames) are presented for \epsilon= 161 MeV. The total cross sections are proportional to the volume of available three-body phase-space indicating that the transition matrix element does not change significantly in this range of excess energies. It is concluded from the differential data that the reaction proceeds dominantly via the N(1710)P_{11} and/or N(1720)P_{13} resonance(s); N(1650)S_{11} and \Delta(1600)P_{33} could also contribute., Comment: 15 pages, 10 figures
Published: 2012
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35. On the SigmaN cusp in the pp -> pK+Lambda reaction

Author: El-Samad, S. Abd, Borodina, E., Brinkmann, K. -Th., Clement, H., Doroshkevich, E., Dzhygadlo, R., Ehrhardt, K., Erhardt, A., Eyrich, W., Freiesleben, H., Gast, W., Gillitzer, A., Grzonka, D., Hanhart, C., Hauenstein, F., Klja, P., Kilian, K., Krapp, M., Ritman, J., Roderburg, E., Roeder, M., Schulte-Wissermann, M., Schroeder, W., Sfzick, T., Wagner, G. J., Wintz, P., and Wuestner, P.
Subjects: High Energy Physics - Experiment (hep-ex), FOS: Physical sciences, Nuclear Experiment (nucl-ex), Nuclear Experiment
Abstract: Measurements of the $pp \to pK^+��$ reaction at $T_p$ = 2.28 GeV have been carried out at COSY-TOF. In addition to the $��p$ FSI and $N^*$ resonance excitation effects a pronounced narrow structure is observed in the Dalitz plot and in its projection on the $p��$-invariant mass. The structure appears at the $pp \to $N$K^+��$ threshold and is interpreted as $��$N cusp effect. The observed width of 20 MeV/$c^2$ is substantially broader than anticipated from previous inclusive measurements. Angular distributions of this cusp structure are shown to be dissimilar to those in the residual $pK^+��$ channel, but similar to those observed in the $pK^+��^0$ channel.
Published: 2012
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36. The pK0��+ final state in proton-proton collisions

Author: TOF Collaboration, Abdel-Bary, M., Abdel-Samad, S., Brinkmann, K-Th., Clement, H., Dietrich, J., Doroshkevich, E., Dshemuchadse, S., Ehrhardt, K., Erhardt, A., Eyrich, W., Filippi, A., Freiesleben, H., Fritsch, M., Gast, W., Georgi, J., Gillitzer, A., Gottwald, J., Hesselbarth, D., J��ger, H., Jakob, B., J��kel, R., Karsch, L., Kilian, K., Koch, H., Krapp, M., Kre��, J., Kuhlmann, E., Lehmann, A., Marcello, S., Marwinski, S., Mauro, S., Meyer, W., Michel, P., M��ller, K., Morsch, H. P., M��rtel, H., Naumann, L., Paul, N., Pinna, L., Pizzolotto, C., Plettner, Ch., Reimann, S., Richter, M., Ritman, J., Roderburg, E., Schamlott, A., Sch��nmeier, P., Schroeder, W., Schulte-Wissermann, M., Sefzick, T., Stinzing, F., Steinke, M., Sun, G. Y., Teufel, A., Ullrich, W., Wagner, G. J., Wagner, M., Wenzel, R., Wilms, A., Wintz, P., Wirthand, S., W��stner, P., and Zupranski, P.
Subjects: Nuclear Theory (nucl-th), FOS: Physical sciences, Nuclear Experiment (nucl-ex)
Abstract: This paper reports results from a study of the reaction pp->pK0��+ at beam momenta of p_{beam} = 2950, 3059, and 3200 MeV/c (excess energies of ��= 126, 161, and 206 MeV). Total cross sections were determined for all energies; a set of differential cross sections (Dalitz plots; invariant mass spectra of all two-body subsystems; angular distributions of all final state particles; distributions in helicity and Jackson frames) are presented for ��= 161 MeV. The total cross sections are proportional to the volume of available three-body phase-space indicating that the transition matrix element does not change significantly in this range of excess energies. It is concluded from the differential data that the reaction proceeds dominantly via the N(1710)P_{11} and/or N(1720)P_{13} resonance(s); N(1650)S_{11} and ��(1600)P_{33} could also contribute., 15 pages, 10 figures
Published: 2012
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37. The pK0Σ+ final state in proton-proton collisions

Author: Abdel-Bary, M., Abdel-Samad, S., Brinkmann, K.-T., Clement, H., Dietrich, J., Doroshkevich, E., Dshemuchadse, S., Ehrhardt, K., Erhardt, A., Eyrich, W., Filippi, A., Freiesleben, H., Fritsch, M., Gast, W., Georgi, J., Gillitzer, A., Gottwald, J., Hesselbarth, D., Jäger, H., Jakob, B., Jäkel, R., Karsch, L., Kilian, K., Koch, H., Krapp, M., Kreß, J., Kuhlmann, E., Lehmann, A., Marcello, S., Marwinski, S., Mauro, S., Meyer, W., Michel, P., Möller, K., Morsch, H. P., Mörtel, H., Naumann, L., Paul, N., Pinna, L., Pizzolotto, C., Plettner, C., Reimann, S., Richter, M., Ritman, J., Roderburg, E., Schamlott, A., Schönmeier, P., Schroeder, W., Schulte-Wissermann, M., Sefzick, T., Stinzing, F., Steinke, M., Sun, G. Y., Teufel, A., Ullrich, W., Wagner, G. J., Wagner, M., Wenzel, R., Wilms, A., Wintz, P., Wirthand, S., Wüstner, P., and Zupranski, P.
Abstract: This paper reports results from a study of the reaction pp->pK0\Sigma+ at beam momenta of p_{beam} = 2950, 3059, and 3200 MeV/c (excess energies of \epsilon= 126, 161, and 206 MeV). Total cross sections were determined for all energies; a set of differential cross sections (Dalitz plots; invariant mass spectra of all two-body subsystems; angular distributions of all final state particles; distributions in helicity and Jackson frames) are presented for \epsilon= 161 MeV. The total cross sections are proportional to the volume of available three-body phase-space indicating that the transition matrix element does not change significantly in this range of excess energies. It is concluded from the differential data that the reaction proceeds dominantly via the N(1710)P_{11} and/or N(1720)P_{13} resonance(s); N(1650)S_{11} and \Delta(1600)P_{33} could also contribute.
Published: 2012

38. Production of Lambda and Sigma^0 hyperons in proton-proton collisions

Author: Collaboration, The COSY-TOF, Abdel-Bary, M., Abdel-Samad, S., Brinkmann, K-Th., Clement, H., Dietrich, J., Doroshkevich, E., Dshemuchadse, S., Ehrhardt, K., Erhardt, A., Eyrich, W., Filges, D., Filippi, A., Freiesleben, H., Fritsch, M., Gast, W., Georgi, J., Gillitzer, A., Gottwald, J., Hesselbarth, D., Jäger, H., Jakob, B., Jäkel, R., Karsch, L., Kilian, K., Koch, H., Krapp, M., Kreß, J., Kuhlmann, E., Lehmann, A., Marcello, S., Marwinski, S., Mauro, S., Meyer, W., Michel, P., Möller, K., Morsch, H. P., Mörtel, H., Naumann, L., Paul, N., Pinna, L., Pizzolotto, C., Plettner, Ch., Reimann, S., Richter, M., Ritman, J., Roderburg, E., Schamlott, A., Schönmeier, P., Schroeder, W., Schulte-Wissermann, M., Sefzick, T., Stinzig, F., Steinke, M., Sun, G. Y., Teufel, A., Ullrich, W., Wagner, G. J., Wagner, M., Wenzel, R., Wilms, A., Wintz, P., Wirth, S., Wüstner, P., and Zupranski, P.
Subjects: Physics, Nuclear and High Energy Physics, Proton, strong interaction, proton-proton collisions, hyperons, hadronic physics, cross sections, differential distributions, Hyperon, FOS: Physical sciences, Sigma, Lambda, Helicity, Nuclear physics, Cross section (geometry), Production (computer science), Nuclear Experiment (nucl-ex), Nucleon, Nuclear Experiment
Abstract: This paper reports results on simultaneous measurements of the reaction channels pp -> pK+\Lambda and pp -> pK+\Sigma^0 at excess energies of 204, 239, and 284 MeV (\Lambda) and 127, 162, and 207 MeV (\Sigma^0). Total and differential cross sections are given for both reactions. It is concluded from the measured total cross sections that the high energy limit of the cross section ratio is almost reached at an excess energy of only about 200 MeV. From the differential distributions observed in the overall CMS as well as in the Jackson and helicity frames, a significant contribution of interfering nucleon resonances to the \Lambda production mechanism is concluded while resonant \Sigma^0-production seems to be of lesser importance and takes place only through specific partial waves of the entrance channel. The data also indicate that kaon exchange plays a minor role in the case of \Lambda- but an important role for \Sigma^0-production. Thus the peculiar energy dependence of the \Lambda-to-\Sigma^0 cross section ratio appears in a new light as its explanation requires more than mere differences between the p\Lambda and the p\Sigma^0 final state interaction. The data provide a benchmark for theoretical models already available or yet to come., Comment: 18 pages, 10 figures; accepted by The European Physical Journal A (EPJ A)
Published: 2010

39. Influence of N*-resonances on hyperon production in the channel pp->K+ Lambda p at 2.95, 3.20 and 3.30 GeV/c beam momentum

Author: Collaboration, COSY-TOF, AbdEl-Samad, S., Abdel-Bary, M., Brinkmann, K., Clement, H., Dietrich, J., Dorochkevitch, E., Dshemuchadse, S., Ehrhardt, K., Erhardt, A., Eyrich, W., Fanara, C., Filges, D., Filippi, A., Freiesleben, H., Fritsch, M., Gast, W., Georgi, J., Gillitzer, A., Gottwald, J., Hauffe, J., Hesselbarth, D., Jaeger, H., Jakob, B., Jaekel, R., Karsch, L., Kilian, K., Koch, H., Krapp, M., Kress, J., Kuhlmann, E., Lehmann, A., Marcello, S., Marwinski, S., Mauro, S., Metzger, A., Meyer, W., Michel, P., Moeller, K., Moertel, H., Morsch, H. P., Naumann, L., Paul, N., Pinna, L., Pizzolotto, C., Plettner, C., Reimann, S., Richter, M., Ritman, J., Roderburg, E., Schamlott, A., Schoenmeier, P., Schulte-Wissermann, M., Schroeder, W., Sefzick, T., Steinke, M., Stinzing, F., Sun, G., Teufel, A., Ullrich, W., Waechter, J., Wagner, G. J., Wagner, M., Wenzel, R., Wilms, A., Wintz, P., Wirth, S., Wuestner, P., and Zupranski, P.
Subjects: Nuclear Experiment
Abstract: Hyperon production in the threshold region was studied in the reaction pp -> K+Lp using the time-of-flight spectrometer COSY-TOF. Exclusive data, covering the full phase-space, were taken at the three different beam momenta of p_beam=2.95, 3.20 and 3.30 GeV/c, corresponding to excess energies of epsilon=204, 285 and 316 MeV, respectively. Total cross-sections were deduced for the three beam momenta to be 23.9+/-0.8 +/-2.0 ub, 28.4+/-1.3 +/-2.2 ub and 35.0+/-1.3 +/-3.0 ub. Differential observables including Dalitz plots were obtained. The analysis of the Dalitz plots reveals a strong influence of the N(1650)-resonance at p_beam=2.95 GeV/c, whereas for the higher momenta an increasing relative contribution of the N(1710)- and/or of the N(1720)-resonance was observed. In addition, the pL-final-state interaction turned out to have a significant influence on the Dalitz plot distribution., Comment: accepted for publication at Physics Letters B; some minor text changes were done; also the scale of the ordinates of figure 9 has been changed
Published: 2010

40. Systematic study of the pp -> pp omega reaction

Author: Abdel-Bary, M., AbdEl-Samad, S., Fanara, C., Filges, D., Filippi, A., Freiesleben, H., Fritsch, M., Gast, W., Georgi, J., Gillitzer, A., Gottwald, J., Hesselbarth, D., Brinkmann, K., Jaeger, H., Jakob, B., Jaekel, R., Karsch, L., Kilian, K., Koch, H., Krapp, M., Kress, J., Kuhlmann, E., Lehmann, A., Clement, H., Marcello, S., Marwinski, S., Mauro, S., Meyer, W., Michel, P., Moeller, K., Moertel, H., Morsch, H.P., Naumann, L., Paul, N., Dietrich, J., Pinna, L., Pizzolotto, C., Plettner, C., Reimann, S., Richter, M., Ritman, J., Roderburg, E., Schamlott, A., Schoenmeier, P, Schulte-Wissermann, M., Dorochkevitch, E., Schroeder, W., Sefzick, T., Steinke, M., Stinzing, F., Sun, G., Teufel, A., Ullrich, W., Waechter, J., Wagner, G. J., Wagner, M., Dshemuchadse, S., Wenzel, R., Wilms, A., Wintz, P., Wirth, S., Wuestner, P., Zupranski, P., Ehrhardt, K., Erhardt, A., and Eyrich, W.
Subjects: model [meson], COSY-TOF, energy dependence [total cross section], +p+p+omega%28783%29%22">p p --> p p omega(783), ddc:530, interaction [p p], Juelich COSY PS, Nuclear Experiment, angular distribution [p], hadroproduction [omega(783)], production [meson], spin [meson]
Abstract: A systematic study of the production of omega-mesons in proton-proton-collisions was carried out in a kinematically complete experiment at three excess energies(epsilon= 92, 128, 173MeV). Both protons were detected using the large-acceptance COSY-TOF spectrometer at an external beam line at the Cooler Synchrotron COSY at Forschungszentrum J\"ulich. The total cross section, angular distributions of both omega-mesons and protons were measured and presented in various reference frames such as the overall CMS, helicity and Jackson frame. In addition, the orientation of the omega-spin and invariant mass spectra were determined. We observe omega-production to take place dominantly in Ss and Sp final states at epsilon = 92, 128 MeV and, additionally, in Sd at epsilon= 173 MeV. No obvious indication of resonant omega-production via N^*-resonances was found, as proton angular distributions are almost isotropic and invariant mass spectra are compatible with phase space distributions. A dominant role of ^3P_1 and ^1S_0 initial partial waves for omega-production was concluded from the orientation of the decay plane of the omega-meson. Although the Jackson angle distributions in the omega-p-Jackson frame are anisotropic we argue that this is not an indication of a resonance but rather a kinematical effect reflecting the anisotropy of the omega angular distribution. The helicity angle distribution in the omega-p-helicity frame shows an anisotropy which probably reflects effects of the omega angular momenta in the final state; this observable may be, in addition to the orientation of the omega decay plane, the most sensitive one to judge the validity of theoretical descriptions of the production process., Comment: 17 pages, 16 figures, accepted for publication in EPJA
Published: 2010
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41. Systematic study of the pp -> pp omega reaction

Author: Abdel-Bary, M., Abdel-Samad, S., Brinkmann, K., Clement, H., Dietrich, J., Doroshkevich, E., Dshemuchadse, S., Ehrhardt, K., Erhardt, A., Eyrich, W., Filippi, A., Freiesleben, H., Fritsch, M., Gast, W., Gillitzer, A., Gottwald, J., Jager, H., Jakob, B., Jakel, R., Karsch, L., Kilian, K., Koch, H., Krapp, M., Kress, J., Kuhlmann, E., Lehmann, A., Marcello, S., Mauro, S., Michel, P., Moller, K., Morsch, H., Naumann, L., Paul, N., Pizzolotto, C., Plettner, C., Reimann, S., Richter, M., Ritman, J., Roderburg, E., Schamlott, A., Schonmeier, P., Schroeder, W., Schulte-Wissermann, M., Sefzick, T., Steinke, M., Sun, G., Teufel, A., Ullrich, W., Wagner, G., Wagner, M., Wenzel, R., Wilms, A., Wintz, P., Wustner, P., and Zupranski, P.
Subjects: +400+MeV%29%22">Other reactions above meson production thresholds (energies > 400 MeV), Nuclear reactions involving few-nucleon systems, nucleon-nucleon interactions, Nucleon-nucleon interactions, Other mesons with S=C=0, mass < 2.5 GeV, vector meson production, polarization in interactions and scattering, Nuclear Experiment, Polarization in interactions and scattering
Abstract: A systematic study of the production of omega-mesons in proton-proton-collisions was carried out in a kinematically complete experiment at three excess energies (epsilon= 92, 128, 173 MeV). Both protons were detected using the large-acceptance COSY-TOF spectrometer at an external beam line at the Cooler Synchrotron COSY at Forschungszentrum J¨ulich. The total cross section, angular distributions of both omega-mesons and protons were measured and presented in various reference frames such as the overall CMS, helicity and Jackson frame. In addition, the orientation of the omega-spin and invariant mass spectra were determined. We observe !-production to take place dominantly in Ss and Sp final states at epsilon = 92, 128 MeV and, additionally, in Sd at epsilon = 173 MeV. No obvious indication of resonant omega-production via N*- resonances was found, as proton angular distributions are almost isotropic and invariant mass spectra are compatible with phase space distributions. A dominant role of 3P1 and 1S0 initial partial waves for omega-production was concluded from the orientation of the decay plane of the !-meson. Although the Jackson angle distributions in the omega-p-Jackson frame are anisotropic we argue that this is not an indication of a resonance but rather a kinematical effect reflecting the anisotropy of the omega angular distribution. The helicity angle distribution in the omega-p-helicity frame shows an anisotropy which probably reflects effects of the omega angular momenta in the final state; this observable may be, in addition to the orientation of the omega decay plane, the most sensitive one to judge the validity of theoretical descriptions of the production process.
Published: 2010

42. Production of L Lambda and S0 Sigma {0}_{} hyperons in proton-proton collisions

Author: Abdel-Bary, M., AbdEl-Samad, S., Filges, D., Filippi, A., Freiesleben, H., Fritsch, M., Gast, W., Georgi, J., Gillitzer, A., Gottwald, J., Hesselbarth, D., Jaeger, H., Brinkmann, K., Jakob, B., Jaekel, R., Karsch, L., Kilian, K., Koch, H., Krapp, M., Kress, J., Kuhlmann, E., Lehmann, A., Marcello, S., Clement, H., Marwinski, S., Mauro, S., Meyer, W., Michel, P., Moeller, K., Moertel, H., Morsch, H.P., Naumann, L., Paul, N., Pinna, L., Dietrich, J., Pizzolotto, C., Plettner, C., Reimann, S., Richter, M., Ritman, J., Roderburg, E., Schamlott, A., Schoenmeier, P, Schulte-Wissermann, M., Schroeder, W., Dorochkevitch, E., Sefzick, T., Steinke, M., Stinzing, F., Sun, G., Teufel, A., Ullrich, W., Waechter, J., Wagner, G. J., Wagner, M., Wenzel, R., Dshemuchadse, S., Wilms, A., Wintz, P., Wirth, S., Wuestner, P., Zupranski, P., Ehrhardt, K., Erhardt, A., and Eyrich, W.
Subjects: exclusive reaction [p p], associated production [K+], +Sigma0+p+K%2B%22">p p --> Sigma0 p K+, hadroproduction [Lambda], Dalitz plot, nucleon resonance, exchange [K], Juelich COSY PS, 3.059: 3.200 GeV/c [2.950], energy dependence [channel cross section], helicity, final-state interaction, angular dependence [differential cross section], COSY-TOF, +Lambda+p+K%2B%22">p p --> Lambda p K+, ddc:530, interference [scattering amplitude], hadroproduction [Sigma0], ratio [cross section], experimental results
Abstract: This paper reports results on simultaneous measurements of the reaction channels pp -> pK(+) Lambda and pp -> pK(+)Sigma(0) at excess energies of 204, 239, and 284 MeV (Lambda) and 127, 162, and 207 MeV (Sigma(0)). Total and differential cross-sections are given for both reactions. It is concluded from the measured total cross-sections that the high-energy limit of the cross-section ratio is almost reached at an excess energy of only about 200 MeV. From the differential distributions observed in the overall CMS as well as in the Jackson and helicity frames, a significant contribution of interfering nucleon resonances to the Lambda production mechanism is concluded while resonant Sigma(0) production seems to be of lesser importance and takes place only through specific partial waves of the entrance channel. The data also indicate that kaon exchange plays a minor role in the case of Lambda but an important role for Sigma(0) production. Thus the peculiar energy dependence of the Lambda/Sigma(0) cross-section ratio appears in a new light as its explanation requires more than mere differences between the p Lambda and the p Sigma(0) final-state interaction. The data provide a benchmark for theoretical models already available or yet to come.
Published: 2010
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43. Systematic study of the pp -> pp omega reaction

Author: TOF Collaboration, Abdel-Bary, M., Abdel-Samad, S., Brinkmann, K. -Th., Clement, H., Dietrich, J., Doroshkevich, E., Dshemuchadse, S., Ehrhardt, K., Erhardt, A., Eyrich, W., Filippi, A., Freiesleben, H., Fritsch, M., Gast, W., Gillitzer, A., Gottwald, J., J��ger, H., Jakob, B., J��kel, R., Karsch, L., Kilian, K., Koch, H., Krapp, M., Kre��, J., Kuhlmann, E., Lehmann, A., Marcello, S., Mauro, S., Michel, P., M��ller, K., Morsch, H. P., Naumann, L., Paul, N., Pizzolotto, C., Plettner, Ch., Reimann, S., Richter, M., Ritman, J., Roderburg, E., Schamlott, A., Sch��nmeier, P., Schroeder, W., Schulte-Wissermann, M., Sefzick, T., Steinke, M., Sun, G. Y., Teufel, A., Ullrich, W., Wagner, G. J., Wagner, M., Wenzel, R., Wilms, A., Wintz, P., W��stner, P., and Zupranski, P.
Subjects: FOS: Physical sciences, Nuclear Experiment (nucl-ex), Nuclear Experiment
Abstract: A systematic study of the production of omega-mesons in proton-proton-collisions was carried out in a kinematically complete experiment at three excess energies(epsilon= 92, 128, 173MeV). Both protons were detected using the large-acceptance COSY-TOF spectrometer at an external beam line at the Cooler Synchrotron COSY at Forschungszentrum J��lich. The total cross section, angular distributions of both omega-mesons and protons were measured and presented in various reference frames such as the overall CMS, helicity and Jackson frame. In addition, the orientation of the omega-spin and invariant mass spectra were determined. We observe omega-production to take place dominantly in Ss and Sp final states at epsilon = 92, 128 MeV and, additionally, in Sd at epsilon= 173 MeV. No obvious indication of resonant omega-production via N^*-resonances was found, as proton angular distributions are almost isotropic and invariant mass spectra are compatible with phase space distributions. A dominant role of ^3P_1 and ^1S_0 initial partial waves for omega-production was concluded from the orientation of the decay plane of the omega-meson. Although the Jackson angle distributions in the omega-p-Jackson frame are anisotropic we argue that this is not an indication of a resonance but rather a kinematical effect reflecting the anisotropy of the omega angular distribution. The helicity angle distribution in the omega-p-helicity frame shows an anisotropy which probably reflects effects of the omega angular momenta in the final state; this observable may be, in addition to the orientation of the omega decay plane, the most sensitive one to judge the validity of theoretical descriptions of the production process., 17 pages, 16 figures, accepted for publication in EPJA
Published: 2010
Full Text: View/download PDF

44. Influence of N*-resonances on hyperon production in the channel pp->K+ Lambda p at 2.95, 3.20 and 3.30 GeV/c beam momentum

Author: AbdEl Samad, S., Abdel Bary, M., Brinkmann, K., Clement, H., Dietrich, J., Dorochkevitch, E., Dshemuchadse, S., Ehrhardt, K., Erhardt, A., Eyrich, W., Fanara, C., Filges, D., Filippi, A., Freiesleben, H., Fritsch, M., Gast, W., Georgi, J., Gillitzer, A., Gottwald, J., Hauffe, J., Hesselbarth, D., Jaeger, H., Jakob, B., Jaekel, R., Karsch, L., Kilian, K., Koch, H., Krapp, M., Kress, J., Kuhlmann, E., Lehmann, A., Marcello, Simonetta, Marwinski, S., Mauro, S., Metzger, A., Meyer, W., Michel, P., Moeller, K., Moertel, H., Morsch, H. P., Naumann, L., Paul, N., Pinna, L., Pizzolotto, C., Plettner, C., Reimann, S., Richter, M., Ritman, J., Roderburg, E., Schamlott, A., Schoenmeier, P., Schulte Wissermann, M., Schroeder, W., Sefzick, T., Steinke, M., Stinzing, F., Sun, G., Teufel, A., Ullrich, W., Waechter, J., Wagner, G. J., Wagner, M., Wenzel, R., Wilms, A., Wintz, P., Wirth, S., Wüstner, P., and Zupranski, P.
Subjects: Associated strangeness production, hyperon production, total cross-section, baryon resonances, Dalitz plot
Published: 2010

45. Influence of N*-resonances on hyperon production in the channel pp->K+ Lambda p at 2.95, 3.20 and 3.30 GeV/c beam momentum

Author: TOF Collaboration, AbdEl-Samad, S., Abdel-Bary, M., Brinkmann, K., Clement, H., Dietrich, J., Dorochkevitch, E., Dshemuchadse, S., Ehrhardt, K., Erhardt, A., Eyrich, W., Fanara, C., Filges, D., Filippi, A., Freiesleben, H., Fritsch, M., Gast, W., Georgi, J., Gillitzer, A., Gottwald, J., Hauffe, J., Hesselbarth, D., Jaeger, H., Jakob, B., Jaekel, R., Karsch, L., Kilian, K., Koch, H., Krapp, M., Kress, J., Kuhlmann, E., Lehmann, A., Marcello, S., Marwinski, S., Mauro, S., Metzger, A., Meyer, W., Michel, P., Moeller, K., Moertel, H., Morsch, H. P., Naumann, L., Paul, N., Pinna, L., Pizzolotto, C., Plettner, C., Reimann, S., Richter, M., Ritman, J., Roderburg, E., Schamlott, A., Schoenmeier, P., Schulte-Wissermann, M., Schroeder, W., Sefzick, T., Steinke, M., Stinzing, F., Sun, G., Teufel, A., Ullrich, W., Waechter, J., Wagner, G. J., Wagner, M., Wenzel, R., Wilms, A., Wintz, P., Wirth, S., Wuestner, P., and Zupranski, P.
Subjects: FOS: Physical sciences, Nuclear Experiment (nucl-ex)
Abstract: Hyperon production in the threshold region was studied in the reaction pp -> K+Lp using the time-of-flight spectrometer COSY-TOF. Exclusive data, covering the full phase-space, were taken at the three different beam momenta of p_beam=2.95, 3.20 and 3.30 GeV/c, corresponding to excess energies of epsilon=204, 285 and 316 MeV, respectively. Total cross-sections were deduced for the three beam momenta to be 23.9+/-0.8 +/-2.0 ub, 28.4+/-1.3 +/-2.2 ub and 35.0+/-1.3 +/-3.0 ub. Differential observables including Dalitz plots were obtained. The analysis of the Dalitz plots reveals a strong influence of the N(1650)-resonance at p_beam=2.95 GeV/c, whereas for the higher momenta an increasing relative contribution of the N(1710)- and/or of the N(1720)-resonance was observed. In addition, the pL-final-state interaction turned out to have a significant influence on the Dalitz plot distribution., accepted for publication at Physics Letters B; some minor text changes were done; also the scale of the ordinates of figure 9 has been changed
Published: 2010
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46. Improved study of a possible Theta+ production in the pp -> pK0 Sigma+ reaction with the COSY-TOF spectrometer

Author: collaboration, COSY-TOF, Abdel-Bary, M., Abdel-Samad, S., Brinkmann, K. -Th., Castelijns, R., Clement, H., Dietrich, J., Dshemuchadse, S., Dorochkevitch, E., Eyrich, W., Ehrhardt, K., Erhardt, A., Freiesleben, H., Gast, W., Georgi, J., Gillitzer, A., Jaeger, H., Jaekel, R., Karsch, L., Kilian, K., Krapp, M., Kuhlmann, E., Lehmann, A., Morsch, H. P., Paul, N., Pinna, L., Pizzolotto, C., Ritman, J., Roderburg, E., Schadmand, S., Schoenmeier, P., Schulte-Wissermann, M., Schroeder, W., Sefzick, T., Teufel, A., Ucar, A., Ullrich, W., Wenzel, R., Wintz, P., Wuestner, P., and Zupranski, P.
Subjects: exclusive reaction [p p], (1) [3.059 GeV/c], hadroproduction [K0], upper limit [channel cross section], associated production [Sigma+], time-of-flight [spectrometer], Juelich COSY PS, High Energy Physics - Experiment, (p K0) [mass spectrum], +Sigma%2B+p+K0%22">p p --> Sigma+ p K0, ddc:530, hadroproduction [pentaquark], Theta(1540), +Theta%281540%29+Sigma%2B%22">p p --> Theta(1540) Sigma+, experimental results
Abstract: The pp -> p K0 Sigma+ reaction was investigated with the TOF spectrometer at COSY at 3.059 GeV/c incident beam momentum. The main objective was to clarify whether or not a narrow exotic S = +1 resnance, the Theta+ pentaquark, is populated at 1.53 GeV/c2 in the K0 p subsystem with a data sample of much higher statistical significance compared to the previously reported data in this channel. An analysis of these data does not confirm the existence of the Theta+ pentaquark. This is expressed as an upper limit for the cross section sigma (pp -> p K0 Sigma+) < 0.15 microbarn at the 95 percent confidence level., Comment: 11 pages, 5 figures
Published: 2007
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47. Improved study of a possible Theta+ production in the pp -> p K0 sigma+ reaction with the COSY-TOF spectrometer

Author: TOF Collaboration, Abdel-Bary, M., Abdel-Samad, S., Brinkmann, K. -Th., Castelijns, R., Clement, H., Dietrich, J., Dshemuchadse, S., Dorochkevitch, E., Eyrich, W., Ehrhardt, K., Erhardt, A., Freiesleben, H., Gast, W., Georgi, J., Gillitzer, A., Jaeger, H., Jaekel, R., Karsch, L., Kilian, K., Krapp, M., Kuhlmann, E., Lehmann, A., Morsch, H. P., Paul, N., Pinna, L., Pizzolotto, C., Ritman, J., Roderburg, E., Schadmand, S., Schoenmeier, P., Schulte-Wissermann, M., Schroeder, W., Sefzick, T., Teufel, A., Ucar, A., Ullrich, W., Wenzel, R., Wintz, P., Wuestner, P., and Zupranski, P.
Subjects: High Energy Physics - Experiment (hep-ex), FOS: Physical sciences
Abstract: The pp -> p K0 Sigma+ reaction was investigated with the TOF spectrometer at COSY at 3.059 GeV/c incident beam momentum. The main objective was to clarify whether or not a narrow exotic S = +1 resnance, the Theta+ pentaquark, is populated at 1.53 GeV/c2 in the K0 p subsystem with a data sample of much higher statistical significance compared to the previously reported data in this channel. An analysis of these data does not confirm the existence of the Theta+ pentaquark. This is expressed as an upper limit for the cross section sigma (pp -> p K0 Sigma+) < 0.15 microbarn at the 95 percent confidence level., 11 pages, 5 figures
Published: 2006
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48. Mediengestalter lernen bei Forschern

Author: Kouchnarev, I., Krapp, M., and Publica
Published: 2000

49. Im Netz der Forschung

Author: Krapp, M., Schiller, S., and Publica
Published: 1999

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