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201. Women Scientists Who Made Nuclear Astrophysics

Author: Claudia Travaglio, Andreea S. Font, Maria Lugaro, Selma E. de Mink, Jacqueline den Hartogh, Artemis Spyrou, P. Gina Isar, Ewa Niemczura, Remo Collet, Birgitta Nordström, Panagiota Papakonstantinou, Marialuisa Aliotta, Sanjana Curtis, W. Chantereau, Mariya Yavahchova, Friedrich-Karl Thielemann, Christine V. Hampton, Thomas Rauscher, A. Ćiprijanović, Claudia Lederer-Woods, Nalan Özkan, Etienne A. Kaiser, Anu Kankainen, Chiaki Kobayashi, Marcella Di Criscienzo, Aparna Venkatesan, Sophie Van Eck, Formicola, Alba, Junker, Matthias, Gialanella, Lucio, and Imbriani, Gianluca
Subjects: naiset, Fission, Nuclear Theory, Astronomy, Nuclear physics, 050109 social psychology, kosmologia, Astrophysics, 01 natural sciences, tähtitiede, Solar studies, 5. Gender equality, History and Philosophy of Physics (physics.hist-ph), Nuclear Experiment (nucl-ex), Nuclear Experiment, 010303 astronomy & astrophysics, Nuclear theory, QC, QB, Earth and Planetary Astrophysics (astro-ph.EP), High Energy Astrophysical Phenomena (astro-ph.HE), Women scientists, Historical, 05 social sciences, Gender studies, tutkijat, Cosmology, Stereotype threat, Radioactivity, Astrophysics - Solar and Stellar Astrophysics, medicine.symptom, Astrophysics - High Energy Astrophysical Phenomena, Psychology, ydinfysiikka, Scientific career, astrofysiikka, education, Physics - History and Philosophy of Physics, FOS: Physical sciences, Negative stereotype, Nuclear Theory (nucl-th), Delusion, 0103 physical sciences, medicine, 0501 psychology and cognitive sciences, Solar and Stellar Astrophysics (astro-ph.SR), radioaktiivisuus, Racial group, Généralités, Astrophysics - Astrophysics of Galaxies, fissio, Astrophysics of Galaxies (astro-ph.GA), Astrophysics - Earth and Planetary Astrophysics
Abstract: Female role models reduce the impact on women of stereotype threat, i.e. of being at risk of conforming to a negative stereotype about oneâ€™s social, gender, or racial group (Fine in Delusion of Gender. W.W. Norton & Co. NY, p. 36, 2010 [1]; Steele and Aronson in J Pers Soc Psychol 69:797â€“811, 1995 [2]). This can lead women scientists to underperform or to leave their scientific career because of negative stereotypes such as, not being as talented or as interested in science as men. Sadly, history rarely provides role models for women scientists; instead, it often renders these women invisible (CafeBabel Homepage [3]). In response to this situation, we present a selection of twelve outstanding women who helped to develop nuclear astrophysics., SCOPUS: cp.p, info:eu-repo/semantics/published
Published: 2019

202. Data for the s Process from n_TOF

Author: Massimi, C., Aberle, O., Alcayne, V., Andrzejewski, J., Audouin, L., Bécares, V., Babiano-Suarez, V., Bacak, M., Barbagallo, M., Benedikt, Th., Bennett, S., Göbel, Kathrin, Gawlik, A., Gilardoni, S., Gonçalves, I. F., González-Romero, E., Guerrero, C., Gunsing, F., Heinitz, S., Heyse, J., Jenkins, D. G., Matteucci, F., Junghans, Arnd R., Käppeler, F., Kadi, Y., Kimura, A., Knapova, I., Kokkoris, M., Kopatch, Y., Krtička, M., Kurtulgil, Deniz, Ladarescu, I., Maugeri, E. A., Lederer-Woods, Claudia, Lonsdale, S. J., Macina, D., Manna, A., Martínez, T., Masi, A., Mastinu, P., Mastromarco, M., Mazzone, A., Mendoza, E., Mengoni, A., Michalopoulou, V., Milazzo, P. M., Mingrone, Federica, Moreno-Soto, J., Musumarra, A., Schillebeeckx, P., Negret, A., Ogállar, F., Oprea, A., Patronis, N., Pavlik, A., Perkowski, J., PIERSANTI, Luciano, Petrone, C., Pirovano, E., Porras, I., Schumann, D., Praena, J., Quesada, J. M., Ramos-Doval, D., Rauscher, Thomas, Reifarth, René, Rochman, D., Sabaté-Gilarte, M., Saxena, A., Sekhar, A., Simone, S., Smith, A. G., Sosnin, N. V., Sprung, P., Stamatopoulos, A., Tagliente, G., Tain, J. L., Berthoumieux, E., Tarifeño-Saldivia, A., Tassan-Got, L., Tsinganis, A., Ulrich, J., Urlass, Sebastian, Valenta, S., Vannini, G., Variale, V., Vaz, P., Ventura, A., Billowes, J., VESCOVI, DIEGO, Vlachoudis, V., Vlastou, R., Wallner, A., Woods, P. J., Wright, T., Žugec, P., n TOF Collaboration, Bosnar, D., Brown, A., Busso, Maurizio, Caamaño, M., Caballero-Ontanaya, L., Calviño, F., Calviani, M., Cano-Ott, D., Casanovas, A., Castelluccio, D. M., Cerutti, F., Chiaveri, E., Clai, G., Colonna, N., Cortés, G., Cortès-Giraldo, M. A., Cosentino, L., CRISTALLO, Sergio, Damone, L. A., Davies, P. J., Dietz, M., Domingo-Pardo, C., Dressler, R., Ducasse, Q., Dupont, E., Durán, I., Eleme, Z., Fernàndez-Dominguez, B., Ferrari, A., Finocchiaro, P., Furman, V., Institut de Physique Nucléaire d'Orsay (IPNO), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Massimi, C., Aberle, O., Alcayne, V., Andrzejewski, J., Audouin, L., Becares, V., Babiano-Suarez, V., Bacak, M., Barbagallo, M., Benedikt, T., Bennett, S., Berthoumieux, E., Billowes, J., Bosnar, D., Brown, A., Busso, M., Caamano, M., Caballero-Ontanaya, L., Calvino, F., Calviani, M., Cano-Ott, D., Casanovas, A., Castelluccio, D. M., Cerutti, F., Chiaveri, E., Clai, G., Colonna, N., Cortes, G., Cortes-Giraldo, M. A., Cosentino, L., Cristallo, S., Damone, L. A., Davies, P. J., Dietz, M., Domingo-Pardo, C., Dressler, R., Ducasse, Q., Dupont, E., Duran, I., Eleme, Z., Fernandez-Dominguez, B., Ferrari, A., Finocchiaro, P., Furman, V., Gobel, K., Gawlik, A., Gilardoni, S., Goncalves, I. F., Gonzalez-Romero, E., Guerrero, C., Gunsing, F., Heinitz, S., Heyse, J., Jenkins, D. G., Junghans, A. R., Kappeler, F., Kadi, Y., Kimura, A., Knapova, I., Kokkoris, M., Kopatch, Y., Krticka, M., Kurtulgil, D., Ladarescu, I., Lederer-Woods, C., Lonsdale, S. J., Macina, D., Manna, A., Martinez, T., Masi, A., Mastinu, P., Mastromarco, M., Matteucci, F., Maugeri, E. A., Mazzone, A., Mendoza, E., Mengoni, A., Michalopoulou, V., Milazzo, P. M., Mingrone, F., Moreno-Soto, J., Musumarra, A., Negret, A., Ogallar, F., Oprea, A., Patronis, N., Pavlik, A., Perkowski, J., Piersanti, L., Petrone, C., Pirovano, E., Porras, I., Praena, J., Quesada, J. M., Ramos-Doval, D., Rauscher, T., Reifarth, R., Rochman, D., Sabate-Gilarte, M., Saxena, A., Schillebeeckx, P., Schumann, D., Sekhar, A., Simone, S., Smith, A. G., Sosnin, N. V., Sprung, P., Stamatopoulos, A., Tagliente, G., Tain, J. L., Tarifeno-Saldivia, A., Tassan-Got, L., Tsinganis, A., Ulrich, J., Urlass, S., Valenta, S., Vannini, G., Variale, V., Vaz, P., Ventura, A., Vescovi, D., Vlachoudis, V., Vlastou, R., Wallner, A., Woods, P. J., Wright, T., Zugec, P., Formicola, Alba, Junker, Matthias, Gialanella, Lucio, Imbriani, Gianluca, Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Massimi C., Aberle O., Alcayne V., Andrzejewski J., Audouin L., Becares V., Babiano-Suarez V., Bacak M., Barbagallo M., Benedikt T., Bennett S., Berthoumieux E., Billowes J., Bosnar D., Brown A., Busso M., Caamano M., Caballero-Ontanaya L., Calvino F., Calviani M., Cano-Ott D., Casanovas A., Castelluccio D.M., Cerutti F., Chiaveri E., Clai G., Colonna N., Cortes G., Cortes-Giraldo M.A., Cosentino L., Cristallo S., Damone L.A., Davies P.J., Dietz M., Domingo-Pardo C., Dressler R., Ducasse Q., Dupont E., Duran I., Eleme Z., Fernandez-Dominguez B., Ferrari A., Finocchiaro P., Furman V., Gobel K., Gawlik A., Gilardoni S., Goncalves I.F., Gonzalez-Romero E., Guerrero C., Gunsing F., Heinitz S., Heyse J., Jenkins D.G., Junghans A.R., Kappeler F., Kadi Y., Kimura A., Knapova I., Kokkoris M., Kopatch Y., Krticka M., Kurtulgil D., Ladarescu I., Lederer-Woods C., Lonsdale S.J., Macina D., Manna A., Martinez T., Masi A., Mastinu P., Mastromarco M., Matteucci F., Maugeri E.A., Mazzone A., Mendoza E., Mengoni A., Michalopoulou V., Milazzo P.M., Mingrone F., Moreno-Soto J., Musumarra A., Negret A., Ogallar F., Oprea A., Patronis N., Pavlik A., Perkowski J., Piersanti L., Petrone C., Pirovano E., Porras I., Praena J., Quesada J.M., Ramos-Doval D., Rauscher T., Reifarth R., Rochman D., Sabate-Gilarte M., Saxena A., Schillebeeckx P., Schumann D., Sekhar A., Simone S., Smith A.G., Sosnin N.V., Sprung P., Stamatopoulos A., Tagliente G., Tain J.L., Tarifeno-Saldivia A., Tassan-Got L., Tsinganis A., Ulrich J., Urlass S., Valenta S., Vannini G., Variale V., Vaz P., Ventura A., Vescovi D., Vlachoudis V., Vlastou R., Wallner A., Woods P.J., Wright T., Zugec P., and n_TOF
Subjects: Physics, Large Hadron Collider, Isotope, 010308 nuclear & particles physics, s-process, n_TOF, neutron capture data, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, 3. Good health, Nuclear physics, Nucleosynthesis, s process, nucleosynthesis, 0103 physical sciences, Neutron, s-process, 010303 astronomy & astrophysics
Abstract: International audience; A considerable amount of (n, $\gamma $ ) reactions has been studied, so far, at the neutron time-of-flight facility n_TOF at CERN. The experimental program aims at determining and improving cross sections for a number of isotopes relevant to s-process nucleosynthesis. A brief summary of some physical cases related to the s-process nucleosyntheis is presented in this work together with ongoing experiments and challenging future programs.
Published: 2018
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203. $^{7}$ Be(n,p)$^{7}$ Li Cross Section Measurement for the Cosmological Lithium Problem at the n $\_$ TOF Facility at CERN

Author: M.J.G. Borge, D. M. Castelluccio, Rene Reifarth, A. Kimura, Stefan Schmidt, Srinivasan Ganesan, D. Macina, Carlos Guerrero, Cortés-Giraldo, G. Bellia, J. M. Quesada, L. Tassan-Got, P. J. Woods, Ignacio Porras, Sergio Cristallo, I. Duran, A. Mengoni, V. Bcares, Alexandru Negret, Juliana Schell, A. Casanovas, K. Rajeev, A. K. Saxena, Tatsuya Katabuchi, A. Ventura, J. Lerendegui-Marco, Maurizio Busso, M. Piscopo, Ariel Tarifeño-Saldivia, S. J. Lonsdale, B. Fernández-Domínguez, S. Rothe, F. Käppeler, Francesca Matteucci, R. Catherall, I. F. Gonçalves, P. Kavrigin, L. Cosentino, D. Bosnar, Ralf Nolte, Javier Praena, S. Lo Meo, M. Brugger, E. Griesmayer, A. Stamatopoulos, L. A. Damone, C. Beinrucker, T. Stora, Claudia Lederer-Woods, E. Leal-Cidoncha, W.I. Furman, E. Chiaveri, A. Gawlik, Thomas Rauscher, P. F. Mastinu, D. Cano-Ott, A.P. Bernardes, Deniz Kurtulgil, P. V. Sedyshev, M. Diakaki, A. S. Brown, J. L. Tain, U. Kohester, J. Balibrea-Correa, E. González-Romero, Niko Kivel, O. Aberle, J. Billowes, N. Colonna, A. Oprea, J. Andrzejewski, A. Pavlik, Y. Kadi, C. Domingo-Pardo, Y. H. Chen, C. Rubbia, Kathrin Göbel, J. Marganiec, B. Marsh, P. M. Milazzo, S. Valenta, Karl Johnston, N. Patronis, G. Tagliente, F. Cerutti, R. Vlastou, Marco Calviani, A. G. Smith, D. Radeck, G. Corts, E. Berthoumieux, P. Vaz, A. Masi, Jan Heyse, D. G. Jenkins, T.D. Goodacre, C. Seiffert, M. Ayranov, Emilio Andrea Maugeri, M. Krtička, Simone Gilardoni, A. Musumarra, J. Ballof, E. Jericha, A. Dorsival, Paolo Finocchiaro, T. Martinez, Dorothea Schumann, M. Kokkoris, C. Weiß, S. Heinitz, J. A. Ryan, Tanja Heftrich, N. V. Sosnin, R. Cardella, A. Riego-Perez, Annamaria Mazzone, Petar Žugec, S. Altstadt, L. Audouin, S. Warren, G. Vannini, F. Bečvář, V. Variale, C. Wolf, E. Mendoza, M. Caamaño, Peter Schillebeeckx, P. C. Rout, A. Kalamara, F. Mingrone, T. J. Wright, E. Dupont, M. Mastromarco, A. J. M. Plompen, A. Garca-Rios, Massimo Barbagallo, M. Dietz, Anton Wallner, Hideo Harada, J.G. Martins Correia, M. Mirea, Rugard Dressler, F. Calviño, H. Leeb, M. Sabaté-Gilarte, A. Tsinganis, Luciano Piersanti, J. Perkowski, F. Gunsing, Vasilis Vlachoudis, Cristian Massimi, A. Ferrari, Pedro G. Ferreira, Mario Weigand, M. Bacak, T. Glodariu, Roberto Losito, Institut de Physique Nucléaire d'Orsay (IPNO), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Institut Laue-Langevin (ILL), n_TOF, ILL, Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Damone, L. A., Barbagallo, M., Mastromarco, M., Mengoni, A., Colonna, N., Cosentino, L., Maugeri, E. A., Heinitz, S., Schumann, D., Dressler, R., Kappeler, F., Finocchiaro, P., Andrzejewski, J., Perkowski, J., Gawlik, A., Aberle, O., Altstadt, S., Ayranov, M., Audouin, L., Bacak, M., Balibrea-Correa, J., Ballof, J., Bcares, V., Becvar, F., Beinrucker, C., Bellia, G., Bernardes, A. P., Berthoumieux, E., Billowes, J., Borge, M. J. G., Bosnar, D., Brown, A., Brugger, M., Busso, M., Caamano, M., Calvino, F., Calviani, M., Cano-Ott, D., Cardella, R., Casanovas, A., Castelluccio, D. M., Catherall, R., Cerutti, F., Chen, Y. H., Chiaveri, E., Corts, G., Cortes-Giraldo, M. A., Cristallo, S., Diakaki, M., Dietz, M., Domingo-Pardo, C., Dorsival, A., Dupont, E., Duran, I., Fernandez-Dominguez, B., Ferrari, A., Ferreira, P., Furman, W., Ganesan, S., Garca-Rios, A., Gilardoni, S., Glodariu, T., Gobel, K., Goncalves, I. F., Gonzalez-Romero, E., Goodacre, T. D., Griesmayer, E., Guerrero, C., Gunsing, F., Harada, H., Heftrich, T., Heyse, J., Jenkins, D. G., Jericha, E., Johnston, K., Kadi, Y., Kalamara, A., Katabuchi, T., Kavrigin, P., Kimura, A., Kivel, N., Kohester, U., Kokkoris, M., Krticka, M., Kurtulgil, D., Leal-Cidoncha, E., Lederer-Woods, C., Leeb, H., Lerendegui-Marco, J., Lo Meo, S., Lonsdale, S. J., Losito, R., Macina, D., Marganiec, J., Marsh, B., Martinez, T., Martins Correia, J. G., Masi, A., Massimi, C., Mastinu, P., Matteucci, F., Mazzone, A., Mendoza, E., Milazzo, P. M., Mingrone, F., Mirea, M., Musumarra, A., Negret, A., Nolte, R., Oprea, A., Patronis, N., Pavlik, A., Piersanti, L., Piscopo, M., Plompen, A., Porras, I., Praena, J., Quesada, J. M., Radeck, D., Rajeev, K., Rauscher, T., Reifarth, R., Riego-Perez, A., Rothe, S., Rout, P., Rubbia, C., Ryan, J., Sabate-Gilarte, M., Saxena, A., Schell, J., Schillebeeckx, P., Schmidt, S., Sedyshev, P., Seiffert, C., Smith, A. G., Sosnin, N. V., Stamatopoulos, A., Stora, T., Tagliente, G., Tain, J. L., Tarifeno-Saldivia, A., Tassan-Got, L., Tsinganis, A., Valenta, S., Vannini, G., Variale, V., Vaz, P., Ventura, A., Vlachoudis, V., Vlastou, R., Wallner, A., Warren, S., Weigand, M., Weiss, C., Wolf, C., Woods, P. J., Wright, T., Zugec, P., Formicola, Alba, Junker, Matthias, Gialanella, Lucio, Imbriani, Gianluca, Damone L.A., Barbagallo M., Mastromarco M., Mengoni A., Colonna N., Cosentino L., Maugeri E.A., Heinitz S., Schumann D., Dressler R., Kappeler F., Finocchiaro P., Andrzejewski J., Perkowski J., Gawlik A., Aberle O., Altstadt S., Ayranov M., Audouin L., Bacak M., Balibrea-Correa J., Ballof J., Bcares V., Becvar F., Beinrucker C., Bellia G., Bernardes A.P., Berthoumieux E., Billowes J., Borge M.J.G., Bosnar D., Brown A., Brugger M., Busso M., Caamano M., Calvino F., Calviani M., Cano-Ott D., Cardella R., Casanovas A., Castelluccio D.M., Catherall R., Cerutti F., Chen Y.H., Chiaveri E., Corts G., Cortes-Giraldo M.A., Cristallo S., Diakaki M., Dietz M., Domingo-Pardo C., Dorsival A., Dupont E., Duran I., Fernandez-Dominguez B., Ferrari A., Ferreira P., Furman W., Ganesan S., Garca-Rios A., Gilardoni S., Glodariu T., Gobel K., Goncalves I.F., Gonzalez-Romero E., Goodacre T.D., Griesmayer E., Guerrero C., Gunsing F., Harada H., Heftrich T., Heyse J., Jenkins D.G., Jericha E., Johnston K., Kadi Y., Kalamara A., Katabuchi T., Kavrigin P., Kimura A., Kivel N., Kohester U., Kokkoris M., Krticka M., Kurtulgil D., Leal-Cidoncha E., Lederer-Woods C., Leeb H., Lerendegui-Marco J., Lo Meo S., Lonsdale S.J., Losito R., Macina D., Marganiec J., Marsh B., Martinez T., Martins Correia J.G., Masi A., Massimi C., Mastinu P., Matteucci F., Mazzone A., Mendoza E., Milazzo P.M., Mingrone F., Mirea M., Musumarra A., Negret A., Nolte R., Oprea A., Patronis N., Pavlik A., Piersanti L., Piscopo M., Plompen A., Porras I., Praena J., Quesada J.M., Radeck D., Rajeev K., Rauscher T., Reifarth R., Riego-Perez A., Rothe S., Rout P., Rubbia C., Ryan J., Sabate-Gilarte M., Saxena A., Schell J., Schillebeeckx P., Schmidt S., Sedyshev P., Seiffert C., Smith A.G., Sosnin N.V., Stamatopoulos A., Stora T., Tagliente G., Tain J.L., Tarifeno-Saldivia A., Tassan-Got L., Tsinganis A., Valenta S., Vannini G., Variale V., Vaz P., Ventura A., Vlachoudis V., Vlastou R., Wallner A., Warren S., Weigand M., Weiss C., Wolf C., Woods P.J., Wright T., and Zugec P.
Subjects: Physics, Large Hadron Collider, 010308 nuclear & particles physics, chemistry.chemical_element, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, BBN, neutron, Nuclear physics, Stars, Cross section (physics), chemistry, Big Bang nucleosynthesis, 7Be(n, p)7Li, Cosmological Lithium Problem, n_TOF, 0103 physical sciences, Nuclear astrophysics, Lithium, Halo, 010306 general physics, Beam (structure)
Abstract: International audience; One of the most puzzling problems in Nuclear Astrophysics is the “Cosmological Lithium Problem”, i.e the discrepancy between the primordial abundance of$^{7}$ Li observed in metal poor halo stars (Asplund et al. in Astrophys J 644:229–259, 2006, [1]), and the one predicted by Big Bang Nucleosynthesis (BBN). One of the reactions that could have an impact on the problem is$^{7}$ Be(n,p)$^{7}$ Li. Despite of the importance of this reaction in BBN, the cross-section has never been directly measured at the energies of interest for BBN. Taking advantage of the innovative features of the second experimental area at the n $\_$ TOF facility at CERN (Sabate-Gilarte et al. in Eur Phys J A 53:210, 2017, [2], Weiss et al. in NIMA 799:90, 2015, [3]), an accurate measurement of$^{7}$ Be(n,p) cross section has been recently performed at n $\_$ TOF, with a pure$^{7}$ Be target produced by implantation of a$^{7}$ Be beam at ISOLDE. The mesurement started in April 2016 and lasted for two months. The experimental procedure, the setup used in the measurement and the results obtained so far will be here presented.
Published: 2018
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204. 23Na(p,γ)24Mg Cross Section Measurements

Author: A. Best, Gianluca Imbriani, Richard deBoer, A. Boeltzig, Michael Wiescher, M. Junker, Antonino DiLeva, Boeltzig, Axel, Best, Andrea, Deboer, Richard J., Dileva, Antonino, Imbriani, Gianluca, Junker, Matthia, and Wiescher, Michael
Subjects: Physics, 010308 nuclear & particles physics, QC1-999, Resonance, 01 natural sciences, Nuclear physics, Reaction rate, Physics and Astronomy (all), Cross section (physics), Stars, 0103 physical sciences, Nuclear astrophysics, Nuclear science, 010306 general physics, National laboratory
Abstract: As a link between the NeNa and MgAl cycles in stellar burning, the reaction 23 Na(p,γ )24 Mg is of interest for various astrophysical scenarios, such as AGB stars. A combined effort at the Laboratory for Underground Nuclear Astrophysics (LUNA) and the Nuclear Science Laboratory (NSL) at the University of Notre Dame aims at a cross section determination for the this reaction, to constrain the astrophysical reaction rate by improving the knowledge of the resonance strengths and the non-resonant component. Experiments at LUNA benefit from the underground location at the Gran Sasso National Laboratory which allows for the measurement of resonances at low energies with high sensitivity in a low background environment. Measurements at the University of Notre Dame pursue a determination of the non-resonant cross section at higher energies. We present the two experiments and the status of the data analysis.
Published: 2017

205. The impact of the revised17O(p, Î±)14N reaction rate on17O stellar abundances and yields

Author: M. Junker, F. Ferraro, M. P. Takács, Gianluca Imbriani, Zsolt Fülöp, R. Menegazzo, Thomas Davinson, E. Samorjai, Sergio Cristallo, Paolo Prati, A. Di Leva, C. G. Bruno, Z. Elekes, D. K. Trezzi, Gyuri Gyürky, Oscar Straniero, F. R. Pantaleo, Marialuisa Aliotta, G. Gervino, F. Cavanna, Antonio Caciolli, Daniel Bemmerer, C. Gustavino, P. Corvisiero, V. Mossa, G. F. Ciani, Rosanna Depalo, A. Best, A. Formicola, A. Boeltzig, Luciano Piersanti, Carlo Broggini, A. Guglielmetti, D. Piatti, Tamás Szücs, Frank Strieder, Straniero, O., Bruno, C. G., Aliotta, M., Best, Andrea, Boeltzig, A., Bemmerer, D., Broggini, C., Caciolli, A., Cavanna, F., Ciani, G. F., Corvisiero, P., Cristallo, S., Davinson, T., Depalo, R., DI LEVA, Antonino, Elekes, Z., Ferraro, F., Formicola, A., Fülöp, Z. s., Gervino, G., Guglielmetti, A., Gustavino, C., Gyürky, G., Imbriani, Gianluca, Junker, M., Menegazzo, R., Mossa, V., Pantaleo, F. R., Piatti, D., Piersanti, L., Prati, P., Samorjai, E., Strieder, F., Szücs, T., Takács, M. P., and Trezzi, D.
Subjects: CNO cycle, Nuclear reactions, nucleosynthesis, abundances – Stars: abundances – Stars: evolution, Nuclear reactions, nucleosynthesis, abundances, Stars: abundances, Stars: evolution, Astronomy and Astrophysics, Space and Planetary Science, Astrophysics, Dredge-up, 01 natural sciences, abundances – Stars: abundances – Stars: evolution, Nucleosynthesis, 0103 physical sciences, Nuclear Astrophysics, Nuclear astrophysics, 010306 general physics, 010303 astronomy & astrophysics, Physics, abundances, nucleosynthesis, Giant star, Interstellar medium, Red-giant branch, Stars, Astrophysics - Solar and Stellar Astrophysics, Nuclear reactions
Abstract: Context. Material processed by the CNO cycle in stellar interiors is enriched in 17O. When mixing processes from the stellar surface reach these layers, as occurs when stars become red giants and undergo the first dredge up, the abundance of 17O increases. Such an occurrence explains the drop of the 16O/17O observed in RGB stars with mass larger than 1.5 M_\solar. As a consequence, the interstellar medium is continuously polluted by the wind of evolved stars enriched in 17O . Aims. Recently, the Laboratory for Underground Nuclear Astrophysics (LUNA) collaboration released an improved rate of the 17O(p,alpha)14N reaction. In this paper we discuss the impact that the revised rate has on the 16O/17O ratio at the stellar surface and on 17O stellar yields. Methods. We computed stellar models of initial mass between 1 and 20 M_\solar and compared the results obtained by adopting the revised rate of the 17O(p,alpha)14N to those obtained using previous rates. Results. The post-first dredge up 16O/17O ratios are about 20% larger than previously obtained. Negligible variations are found in the case of the second and the third dredge up. In spite of the larger 17O(p,alpha)14N rate, we confirm previous claims that an extra-mixing process on the red giant branch, commonly invoked to explain the low carbon isotopic ratio observed in bright low-mass giant stars, marginally affects the 16O/17O ratio. Possible effects on AGB extra-mixing episodes are also discussed. As a whole, a substantial reduction of 17O stellar yields is found. In particular, the net yield of stars with mass ranging between 2 and 20 M_\solar is 15 to 40% smaller than previously estimated. Conclusions. The revision of the 17O(p,alpha)14N rate has a major impact on the interpretation of the 16O/17O observed in evolved giants, in stardust grains and on the 17O stellar yields., Comment: Accepted by A&A
Published: 2017

206. 22Ne and23Na ejecta from intermediate-mass stars: The impact of the new LUNA rate for 22Ne(p, Î³)23Na

Author: Slemer, A., Marigo, P., Piatti, D., Aliotta, M., Bemmerer, D., Best, A., Boeltzig, A., Bressan, A., Broggini, C., Bruno, C. G., Caciolli, A., Cavanna, F., Ciani, G. F., Corvisiero, P., Davinson, T., Depalo, R., Di Leva, A., Elekes, Z., Ferraro, F., Formicola, A., F\\\', Zs., l\\\', p, Gervino, G., Guglielmetti, A., Gustavino, C., Gy\\\', G., rky, Imbriani, G., Junker, M., Menegazzo, R., Mossa, V., Pantaleo, F. R., Prati, P., Straniero, O., Sz\\\', T., Tak\', M. P., Trezzi, D., Slemer, A., Marigo, P., Piatti, D., Aliotta, M., Bemmerer, D., Best, Andrea, Boeltzig, A., Bressan, A., Broggini, C., Bruno, C. G., Caciolli, A., Cavanna, F., Ciani, G. F., Corvisiero, P., Davinson, T., Depalo, R., DI LEVA, Antonino, Elekes, Z., Ferraro, F., Formicola, A., Fülöp, Z. s., Gervino, G., Guglielmetti, A., Gustavino, C., Gyürky, G., Imbriani, Gianluca, Junker, M., Menegazzo, R., Mossa, V., Pantaleo, F. R., Prati, P., Straniero, O., Szücs, T., Takács, M. P., and Trezzi, D.
Subjects: Stars: mass loss, abundances – stars: abundances – stars: AGB and post-AGB – stars: carbon – stars: evolution – stars: mass loss, K-type main-sequence star, Metallicity, Astrophysics, nuclear reactions, nucleosynthesis, abundances, stars: abundances, stars: AGB and post-AGB, stars: carbon, stars: evolution, stars: mass loss, 01 natural sciences, Settore FIS/05 - Astronomia e Astrofisica, 0103 physical sciences, Asymptotic giant branch, Abundances, 010306 general physics, Ejecta, 010303 astronomy & astrophysics, Physics, Stars: abundances, Stars: AGB and post-AGB, Order (ring theory), Astronomy, Astronomy and Astrophysics, Stars, T Tauri star, Stars: carbon, Stars: evolution, nuclear reactions, nucleosynthesis, abundances – stars: abundances – stars: AGB and post-AGB – stars: carbon – stars: evolution – stars: mass loss, Astrophysics - Solar and Stellar Astrophysics, Nuclear reactions, Nucleosynthesis, Space and Planetary Science, 13. Climate action, Stellar mass loss
Abstract: We investigate the impact of the new LUNA rate for the nuclear reaction $^{22}$Ne$(p,\gamma)^{23}$Na on the chemical ejecta of intermediate-mass stars, with particular focus on the thermally-pulsing asymptotic giant branch (TP-AGB) stars that experience hot-bottom burning. To this aim we use the PARSEC and COLIBRI codes to compute the complete evolution, from the pre-main sequence up to the termination of the TP-AGB phase, of a set of stellar models with initial masses in the range $3.0\,M_{\odot} - 6.0\,M_{\odot}$, and metallicities $Z_{\rm i}=0.0005$, $Z_{\rm i}=0.006$, and $Z_{\rm i} = 0.014$. We find that the new LUNA measures have much reduced the nuclear uncertainties of the $^{22}$Ne and $^{23}$Na AGB ejecta, which drop from factors of $\simeq 10$ to only a factor of few for the lowest metallicity models. Relying on the most recent estimations for the destruction rate of $^{23}$Na, the uncertainties that still affect the $^{22}$Ne and $^{23}$Na AGB ejecta are mainly dominated by evolutionary aspects (efficiency of mass-loss, third dredge-up, convection). Finally, we discuss how the LUNA results impact on the hypothesis that invokes massive AGB stars as the main agents of the observed O-Na anti-correlation in Galactic globular clusters. We derive quantitative indications on the efficiencies of key physical processes (mass loss, third dredge-up, sodium destruction) in order to simultaneously reproduce both the Na-rich, O-poor extreme of the anti-correlation, and the observational constraints on the CNO abundance. Results for the corresponding chemical ejecta are made publicly available., Comment: 21 pages, 14 figures, accepted for publication in MNRAS
Published: 2017

207. Shell and explosive hydrogen burning

Author: Boeltzig, A., Bruno, C. G., Cavanna, F., Cristallo, S., Davinson, T., Depalo, R., deBoer, R. J., Di Leva, A., Ferraro, F., Imbriani, G., Marigo, P., Terrasi, F., Wiescher, M., Boeltzig, A., Bruno, C. G., Cavanna, F., Cristallo, S., Davinson, T., Depalo, R., Deboer, R. J., DI LEVA, Antonino, Ferraro, F., Imbriani, Gianluca, Marigo, P., Terrasi, F., and Wiescher, M.
Subjects: FOS: Physical sciences, Experimental Nuclear Astrophysics, nuclear reactions, stellar evolution, Nuclear Experiment (nucl-ex), Nuclear Experiment
Abstract: The nucleosynthesis of light elements, from helium up to silicon, mainly occurs in Red Giant and Asymptotic Giant Branch stars and Novae. The relative abundances of the synthesized nuclides critically depend on the rates of the nuclear processes involved, often through non-trivial reaction chains, combined with complex mixing mechanisms. In this review, we summarize the contributions made by LUNA experiments in furthering our understanding of nuclear reaction rates necessary for modeling nucleosynthesis in AGB stars and Novae explosions., 23 pages, 12 figures
Published: 2016

208. Cross-section measurements at astrophysically relevant energies: The LUNA experiment

Author: C. G. Bruno, Gianluca Imbriani, Davide Trezzi, C. Gustavino, Carlo Broggini, Gy. Gyürky, G. Gervino, Daniel Bemmerer, A. Di Leva, M. Junker, Tamás Szücs, Paolo Prati, R. Menegazzo, Antonio Caciolli, E. Somorjai, A. Formicola, M. Anders, F. Cavanna, Z. Elekes, Douglas Scott, P. Corvisiero, Rosanna Depalo, Frank Strieder, Oscar Straniero, Marialuisa Aliotta, Zs. Fülöp, A. Guglielmetti, A., Formicola, C. G., Bruno, A., Caciolli, F., Cavanna, R., Depalo, DI LEVA, Antonino, D. A., Scott, D., Trezzi, M., Aliotta, M., Ander, D., Bemmerer, C., Broggini, P., Corvisiero, Z., Eleke, F?l?p, Z. s., G., Gervino, A., Guglielmetti, C., Gustavino, Gy?rky, G. y., Imbriani, Gianluca, M., Junker, R., Menegazzo, P., Prati, E., Somorjai, O., Straniero, F., Strieder, and T., Sz?cs
Subjects: Nuclear and High Energy Physics, S-factor, Underground accelerator, Astrophysics::High Energy Astrophysical Phenomena, Measure (physics), Astrophysics::Cosmology and Extragalactic Astrophysics, Luminosity, Nuclear physics, Nucleosynthesis, Nuclear astrophysics, Astrophysics::Solar and Stellar Astrophysics, underground measurements, Nuclear Astrophysic, Nuclear Experiment, Instrumentation, Astrophysics::Galaxy Astrophysics, Experimental Nuclear Physic, Physics, COSMIC cancer database, Solar fusion, LUNA, Stars, Neutrino, Big Bang nucleosynthesis, Direct cross-section
Abstract: Accurate knowledge of thermonuclear reaction rates is important in understanding the generation of energy, the luminosity of neutrinos, and the synthesis of elements in stars. Cross-section measurements for quiescent stellar H-burning are mainly hampered by extremely low counting rate and cosmic background. The LUNA Collaboration has shown that, by going underground and by using the typical techniques of low background physics, it is possible to measure nuclear cross-sections down to the energy of the nucleosynthesis inside stars. This paper reports an overview of the experimental techniques adopted in underground nuclear astrophysics through a summary of the main recent results and achievements. The future developments of the LUNA experiment are also given. © 2013 Elsevier B.V. All rights reserved.
Published: 2014
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209. FLUORINE ABUNDANCES IN GALACTIC ASYMPTOTIC GIANT BRANCH STARS

Author: P. de Laverny, Gianluca Imbriani, Kjell Eriksson, I. Dominguez, Alejandra Recio-Blanco, Rurik Wahlin, Oscar Straniero, Katia Cunha, Sergio Cristallo, Lucio Gialanella, Verne V. Smith, K. H. Hinkle, Carlos Abia, Abia, C., Cunha, K., Cristallo, S., de Laverny, P., Domínguez, I., Eriksson, K., Gialanella, L., Hinkle, K., Imbriani, Gianluca, Recio Blanco, A., Smith, V. V., Stranier, O., and Wahlin, R.
Subjects: Physics, abundance, K-type main-sequence star, Astronomy, chemistry.chemical_element, Astronomy and Astrophysics, stars: AGB and post-AGB, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, nuclear reaction, stars: abundance, Carbon star, stars: carbon, Stars, chemistry, nucleosynthesi, Space and Planetary Science, Abundance (ecology), Nucleosynthesis, Astrophysics::Solar and Stellar Astrophysics, Asymptotic giant branch, Astrophysics::Earth and Planetary Astrophysics, Carbon, Astrophysics::Galaxy Astrophysics, Main sequence
Abstract: An analysis of the fluorine abundance in Galactic asymptotic giant branch (AGB) carbon stars (24 N-type, 5 SC-type, and 5 J-type) is presented. This study uses the state-of-the-art carbon-rich atmosphere models and improved atomic and molecular line lists in the 2.3 μm region. Significantly lower F abundances are obtained in comparison to previous studies in the literature. This difference is mainly due to molecular blends. In the case of carbon stars of SC-type, differences in the model atmospheres are also relevant. The new F enhancements are now in agreement with the most recent theoretical nucleosynthesis models in low-mass AGB stars, solving the long-standing problem of F in Galactic AGB stars. Nevertheless, some SC-type carbon stars still show larger F abundances than predicted by stellar models. The possibility that these stars are of larger mass is briefly discussed.
Published: 2010
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210. A new AMS facility in Caserta/Italy

Author: Vincenzo Roca, Isabella Passariello, Gianluca Imbriani, Filippo Terrasi, Mario R. Romano, Mauro Rubino, G. Casa, Carlo Sabbarese, Fabio Marzaioli, Lucio Gialanella, N. De Cesare, Roger Loger, M.L. Sundquist, Antonio D'Onofrio, Carmine Lubritto, A. Palmieri, Detlef Rogalla, F., Terrasi, D., Rogalla, N., De Cesare, A., Donofrio, C., Lubritto, F., Marzaioli, I., Passariello, M., Rubino, C., Sabbarese, G., Casa, A., Palmieri, L., Gialanella, Imbriani, Gianluca, Roca, Vincenzo, M., Romano, M., Sundquist, R., Roger, Terrasi, Filippo, Rogalla, D., De Cesare, N., D'Onofrio, Antonio, Lubritto, Carmine, Marzaioli, Fabio, Passariello, I., Rubino, M., Sabbarese, Carlo, Casa, G., Palmieri, A., Gialanella, Lucio, Imbriani, G., Roca, V., Romano, M., Sundquist, M., and Roger, R.
Subjects: Nuclear and High Energy Physics, chemistry.chemical_element, Accelerator mass spectrometry, Uranium, Archaeology, Radiocarbon, Experimental Nuclear Physics, law.invention, chemistry, Accelerator Mass Spectroscopy, law, Environmental science, Radiocarbon dating, Instrumentation
Abstract: A new AMS system has been installed at Center for Isotopic Research on Cultural and Environmental Heritage (CIRCE) in Caserta/ Italy. It was built by National Electrostatics Corp. Middleton, WI/USA, and arrived at CIRCE in the middle of January 2005; the installation and the acceptance tests were completed at the end of February 2005. At first, the system is intended for Radiocarbon AMS; for future Al and Be AMS only minor upgrades are needed and the magnets are designed to bend heavy isotopes like Uranium. Concerning Radiocarbon AMS, the first measurements of unknown samples, prepared in the internal preparation laboratory, already yielded results of high precision and C-14 dating is in full swing. (c) 2007 Elsevier B.V. All rights reserved.
Published: 2007
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211. The branchings of the main s-process: their sensitivity to α-induced reactions on 13C and 22Ne and to the uncertainties of the nuclear network

Author: Gianluca Imbriani, Richard deBoer, R. Gallino, Sara Bisterzo, F. Käppeler, Joachim Görres, Oscar Straniero, Sergio Cristallo, Michael Wiescher, ITA, USA, DEU, Bisterzo, S., Gallino, R., Käppeler, F., Wiescher, M., Imbriani, Gianluca, Straniero, O., Cristallo, S., Görres, J., and Deboer, R. J.
Subjects: Physics, Nuclear reaction, Stars: abundance, Isotope, Nuclear Theory, Stars: AGB and post-AGB, FOS: Physical sciences, Astronomy and Astrophysics, Nuclear physics, Neutron capture, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, Nucleosynthesis, Stars: low-ma, Astrophysics::Solar and Stellar Astrophysics, Neutron source, Neutron, Nuclide, Nuclear reactions, nucleosynthesis, abundance, Atomic physics, Nuclear Experiment, s-process, Solar and Stellar Astrophysics (astro-ph.SR)
Abstract: This paper provides a detailed analysis of the main component of the slow neutron capture process (the s-process), which accounts for the solar abundances of half of the nuclei with 90, Comment: 43 pages, 17 Figures, 4 Tables, Supporting Information
Published: 2015

212. New measurement of 7Be half-life in different metallic environments

Author: Lucio Gialanella, F. Raiola, Gianluca Imbriani, Filippo Terrasi, Frank Strieder, B. Limata, Zs. Fülöp, Detlef Rogalla, E. Somorjai, Mario R. Romano, Antonio Esposito, Antonio D'Onofrio, Vincenzo Roca, D. Schürmann, N. De Cesare, C. Rolfs, Gy. Gyürky, B. N., Limata, Z., Fulop, D., Shuerman, N., De Cesare, D'Onofrio, A. n. t., A., Esposito, L., Gialanella, G., Gyurky, Imbriani, Gianluca, F., Raiola, Roca, Vincenzo, D., Rogalla, C., Rolf, M., Romano, M., Somorjai, F., Strider, F., Terrasi, Limatala, Bn, Fulop, Z, Schurmann, D, De Cesare, N, D'Onofrio, Antonio, Esposito, A, Gialanella, Lucio, Gyurky, G, Imbriani, G, Raiola, F, Roca, V, Rogalla, D, Rolfs, C, Romano, M, Somorjai, E, Strieder, F, and Terrasi, Filippo
Subjects: Physics, Nuclear and High Energy Physics, Electron density, Zirconium, Ion beam, Electron capture, Gamma ray, Tantalum, chemistry.chemical_element, Electron, Tungsten, Nuclear physics, Radioactivity, chemistry, half life, Atomic physics
Abstract: (7)Be decays via electron capture and therefore its half-life is expected to depend on the electron density at the nucleus. We measured the (7)Be half-life in palladium, tungsten, zirconium and tantalum metals, in order to investigate the influence of the quasi-free electrons in metals on the probability of electron capture. The (7)Be samples were obtained implanting a 4.85 MeV pure radioactive (7)Be ion beam. The (7)Be half-life was determined measuring the 478 keV gamma decay following the electron capture by means of HPGe detectors. In order to reduce systematic errors, we planned to perform independent measurements in three different laboratories: Naples (Italy), Bochum (Germany) and Debrecen (Hungary). On the basis of the first results, we do not find a (7)Be half-life change within the experimental errors of 0.4%. RI Fulop, Zsolt/B-2262-2008
Published: 2006
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213. Enhanced d(d,p)t fusion reaction in metals

Author: Hans Werner Becker, H. Luis, Carlo Broggini, F. Raiola, M. Junker, Antonio D'Onofrio, Mario R. Romano, Gianluca Imbriani, Marialuisa Aliotta, B. Limata, Filippo Terrasi, João Cruz, S. Zeng, Lucio Gialanella, Vincenzo Roca, M. Fonseca, Frank Strieder, Zs. Fülöp, J.P. Ribeiro, A. P. Jesus, C. Rolfs, Gy. Gyürky, B. Burchard, A. Di Leva, E. Somorjai, F., Raiola, B., Burchard, Fülöp, Z. s., Gyürky, G. y., S., Zeng, J., Cruz, DI LEVA, Antonino, Limata, BENEDICTA NORMANNA, M., Fonseca, H., Lui, M., Aliotta, H. W., Becker, C., Broggini, A., D'Onofrio, L., Gialanella, Imbriani, Gianluca, A. P., Jesu, M., Junker, J. P., Ribeiro, Roca, Vincenzo, C., Rolf, Romano, Mario, E., Somorjai, F., Strieder, F., Terrasi, Raiola, F, Burchard, B, Fulop, Z, Gyurky, Gy, Zeng, S, Cruz, J, Di Leva, A, Limata, B, Fonseca, M, Luis, H, Aliotta, M, Becker, Hw, Broggini, C, D'Onofrio, Antonio, Gialanella, Lucio, Imbriani, G, Jesus, Ap, Junker, M, Ribeiro, Jp, Roca, V, Rolfs, C, Romano, M, Somorjai, E, Strieder, F, and Terrasi, Filippo
Subjects: Lanthanide, Physics, electron screening, Nuclear and High Energy Physics, Hydrogen, Screening effect, Analytical chemistry, chemistry.chemical_element, Metal, symbols.namesake, Deuterium, chemistry, visual_art, visual_art.visual_art_medium, symbols, Debye temperature, Atomic physics, Solubility, Valence electron, deuterated metal, Debye model
Abstract: The electron screening in the d(d,p)t reaction has been studied for the deuterated metal Pt at a target temperature T = 20 degrees C to 340 degrees C, and for Co at T = 20 degrees C and 200 degrees C. The enhanced electron screening decreases with increasing temperature, where the data agree with the plasma model of Debye applied to the quasi-free metallic electrons. The data represent the first observation of a temperature dependence of a nuclear cross-section. We also measured the screening effect for the deuterated metal Ti (an element of group 4 of the periodic table) at T = -10 degrees C to 200 degrees C: above 50 degrees C the hydrogen solubility dropped to values far below unity and a large screening effect became observable. Similarly, all metals of groups 3 and 4 and the lanthanides showed a solubility of a few percent at T = 200 degrees C (compared to T = 20 degrees C) and a large screening became also observable. Within the Debye model the deduced number of valence electrons per metallic atom agrees with the corresponding number from the Hall coefficient, for all metals investigated. RI Fulop, Zsolt/B-2262-2008; Aliotta, Marialuisa /H-2567-2012
Published: 2006
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214. S-factor of 14N(p,γ)15O at astrophysical energies⋆

Author: M. Junker, C. Rolfs, Mario R. Romano, A. Lemut, E. Somorjai, Carlo Broggini, A. Formicola, Gianluca Imbriani, J. N. Klug, Gy. Gyürky, Alberto Vomiero, A. Guglielmetti, C. Gustavino, R. Bonetti, Daniel Bemmerer, R. Menegazzo, C. Rossi Alvarez, D. Schürmann, Zs. Fülöp, Frank Strieder, A. P. Jesus, F. Confortola, P. Corvisiero, Vincenzo Roca, G. Gervino, Oscar Straniero, Filippo Terrasi, Carmen Angulo, H. Costantini, F. Schümann, Paolo Prati, Jenniffer Cruz, H. P. Trautvetter, Pierre Descouvemont, Imbriani, Gianluca, H., Costantini, A., Formicola, A., Vomiero, C., Angulo, D., Bemmerer, R., Bonetti, C., Broggini, F., Confortola, P., Corvisiero, J., Cruz, P., Descouvemont, Z., Fülöp, G., Gervino, A., Guglielmetti, C., Gustavino, Gyürky, G. y., A. P., Jesu, M., Junker, J. N., Klug, A., Lemut, R., Menegazzo, P., Prati, Roca, Vincenzo, C., Rolf, Romano, Mario, C., Rossi Alvarez, F., Schümann, D., Schürmann, E., Somorjai, O., Straniero, F., Strieder, F., Terrasi, H. P., Trautvetter, Z., Fulop, Gyurky, G. Y., C., ROSSI ALVAREZ, F., Schumann, and D., Schurmann
Subjects: Experimental Nuclear Physic, Physics, Nuclear and High Energy Physics, Work (thermodynamics), 010308 nuclear & particles physics, S-factor, FOS: Physical sciences, chemistry.chemical_element, underground laboratory, 01 natural sciences, Nuclear physics, chemistry, 0103 physical sciences, Level structure, Nuclear Experiment (nucl-ex), Nuclear Astrophysic, Tin, Nuclear Experiment, 010303 astronomy & astrophysics, Value (mathematics)
Abstract: The astrophysical S-factor of 14N(p,gamma)15O has been measured for effective center-of-mass energies between E_eff = 119 and 367 keV at the LUNA facility using TiN solid targets and Ge detectors. The data are in good agreement with previous and recent work at overlapping energies. R-matrix analysis reveals that due to the complex level structure of 15O the extrapolated S(0) value is model dependent and calls for additional experimental efforts to reduce the present uncertainty in S(0) to a level of a few percent as required by astrophysical calculations., Comment: Eur. Phys. J. A, accepted. 17 pages, 15 figures
Published: 2005
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215. Electron screening in d(d, p)t for deuterated metals: temperature effects

Author: F Raiola, the LUNA Collaboration, B Burchard, Z Fülöp, G Gyürky, S Zeng, J Cruz, A Di Leva, B Limata, M Fonseca, H Luis, M Aliotta, H W Becker, C Broggini, A DÒnofrio, L Gialanella, G Imbriani, A P Jesus, M Junker, J P Ribeiro, V Roca, C Rolfs, M Romano, E Somorjai, F Strieder, F Terrasi, F., Raiola, the LUNA, Collaboration, B., Burchard, Z., Fülöp, G., Gyürky, S., Zeng, J., Cruz, DI LEVA, Antonino, Limata, BENEDICTA NORMANNA, M., Fonseca, H., Lui, M., Aliotta, H. W., Becker, C., Broggini, A., Dònofrio, L., Gialanella, Imbriani, Gianluca, A. P., Jesu, M., Junker, J. P., Ribeiro, Roca, Vincenzo, C., Rolf, Romano, Mario, E., Somorjai, F., Strieder, and F., Terrasi
Subjects: Physics, Nuclear and High Energy Physics, Hydrogen, Screening effect, Analytical chemistry, chemistry.chemical_element, Metal, symbols.namesake, Deuterium, chemistry, visual_art, Atom, visual_art.visual_art_medium, symbols, Solubility, Atomic physics, Valence electron, Debye model
Abstract: The electron screening in the d(d, p)t reaction has been studied for the deuterated metal Pt at a sample temperature T = 20 ◦C–340 ◦C and for Co at T = 20 ◦C and 200 ◦C. The enhanced electron screening decreases with increasing temperature, where the data agree with the plasma model of Debye applied to the quasi-free metallic electrons. The data represent the first observation of a temperature dependence of a nuclear cross section. We also measured the screening effect for the deuterated metal Ti (an element of group 4 of the periodic table) at T = −10 ◦C–200 ◦C: above 50 ◦C, the hydrogen solubility dropped to values far below 1 and a large screening effect became observable. Similarly, all metals of groups 3 and 4 and the lanthanides showed a solubility of a few per cent at T=200 ◦C (compared to T=20 ◦C) and a large screening also became observable. Within the Debye model, the deduced number of valence electrons per metallic atom agrees with the corresponding number from the Hall coefficient, for all metals investigated. (Some figures in this article are in colour only in the
Published: 2005
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216. The bottleneck of CNO burning and the age of Globular Clusters

Author: H. P. Trautvetter, R. Bonetti, H. Costantini, R. Menegazzo, Oscar Straniero, Gianluca Imbriani, P. Corvisiero, Filippo Terrasi, A. Formicola, Frank Strieder, Zsolt Fülöp, C. Gustavino, C. Rossi Alvarez, A. Guglielmetti, Gyuri Gyürky, Jenniffer Cruz, Alberto Vomiero, Sandra Zavatarelli, E. Somorjai, G. Gervino, M. Junker, Mario R. Romano, A. Lemut, Vincenzo Roca, Paolo Prati, Carlo Broggini, A. P. Jesus, F. Schümann, C. Rolfs, Daniel Bemmerer, G., Imbriani, H., Costantini, A., Formicola, D., Bemmerer, R., Bonetti, C., Broggini, P., Corvisiero, J., Cruz, Z., Fulop, G., Gervino, A., Guglielmetti, C., Gustavino, G., Gyurky, A. P., Jesu, M., Junker, A., Lemut, R., Menegazzo, P., Prati, V., Roca, C., Rolf, M., Romano, C., ROSSI ALVAREZ, F., Schumann, E., Somorjai, O., Straniero, F., Strieder, Terrasi, Filippo, H. P., Trautvetter, A., Vomiero, S., Zavatarelli, Imbriani, Gianluca, Costantini, H., Formicola, A., Bemmerer, D., Bonetti, R., Broggini, C., Corvisiero, P., Cruz, J., Fülöp, Z., Gervino, G., Guglielmetti, A., Gustavino, C., Gyürky, G., Jesus, A. P., Junker, M., Lemut, A., Menegazzo, R., Prati, P., Roca, Vincenzo, Rolfs, C., Romano, Mario, Rossi Alvarez, C., Schümann, F., Somorjai, E., Straniero, O., Strieder, F., Terrasi, F., Trautvetter, H. P., Vomiero, A., and Zavatarelli, S.
Subjects: Physics, 010308 nuclear & particles physics, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, 01 natural sciences, Bottleneck, Luminosity, stars: evolution - stars: population II - nuclear reaction, Red-giant branch, Reaction rate, Stars, Low energy, nucleosynthesi, Space and Planetary Science, Globular cluster, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, abundances - Galaxy: globular clusters, Low Mass, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics
Abstract: The transition between the Main Sequence and the Red Giant Branch in low mass stars is powered by the onset of the CNO burning, whose bottleneck is the $^{14}$N(p,$\gamma)^{15}$O. The LUNA collaboration has recently improved the low energy measurements of the cross section of this key reaction. We analyse the impact of the revised reaction rate on the estimate of the Globular Clusters ages, as derived from the turnoff luminosity. We found that the age of the oldest Globulars should be increased by about 0.7-1 Gyr with respect to the current estimates.
Published: 2004
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217. Recoil separator ERNA: acceptances in angle and energy

Author: Gianluca Imbriani, A. Ordine, H. P. Trautvetter, Marialuisa Aliotta, Filippo Terrasi, Lucio Gialanella, Frank Strieder, N. DeCesare, J. Kluge, Detlef Rogalla, H. Röcken, D. Schürmann, Mario R. Romano, Carmine Lubritto, A. DiLeva, Vincenzo Roca, Antonio D'Onofrio, C. Rolfs, F. Schümann, D., Rogalla, D., Schürmann, F., Strieder, M., Aliotta, N., Decesare, DI LEVA, Antonino, C., Lubritto, A., D’Onofrio, L., Gialanella, Imbriani, Gianluca, J., Kluge, A., Ordine, Roca, Vincenzo, H., Röcken, C., Rolf, Romano, Mario, F., Schümann, F., Terrasi, H. P., Trautvetter, Rogalla, D, Schurmann, D, Strieder, F, Aliotta, M, Di Leva, A, Lubritto, Carmine, De Cesare, N, D'Onofrio, Antonio, Gialanella, Lucio, Imbriani, G, Klug, J, Ordine, A, Roca, V, Rocken, H, Rolfs, C, Romano, M, Schumann, F, Terrasi, Filippo, and Trauttvetter, H. P.
Subjects: Physics, Nuclear and High Energy Physics, Range (particle radiation), Electromagnetic radiation, Recoil separator, Nuclear physics, Cross section (physics), Nuclear Astrophysics, Atomic physics, Experimental nuclear physic, Nuclear Experiment, Dynamitron, Instrumentation, Energy (signal processing), Beam (structure), Oxygen-16
Abstract: For improved cross-section measurements of the reaction 12C(α,γ)16O in inverted kinematics, a recoil separator ERNA is developed at the 4MV Dynamitron tandem accelerator in Bochum to detect directly the 16O recoils with high efficiency. Due to the emission of the capture γ-rays, the kinematically forward directed 16O recoils are described by an angle and energy spread. Thus, the acceptances in angle and energy of ERNA must cover these spreads in order to extract reliable cross-section values. We report on such acceptance measurements over the energy range Ecm=0.7-5.0 MeV, using an 16O pilot beam. © 2003 Elsevier B.V. All rights reserved.
Published: 2003
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218. A new study of the 14N(p,γ)15O reaction at low energy

Author: Gianluca Imbriani, A. Formicola, H. Costantini, A., Formicola, H., Costantini, and Imbriani, Gianluca
Subjects: Experimental Nuclear Physic, Physics, Nuclear reaction, Nuclear and High Energy Physics, Particle physics, Measure (physics), Coulomb barrier, Electron, underground laboratory, Charged particle, Cosmology, Nuclear physics, Cross section (physics), Nuclear astrophysics, Nuclear Astrophysic, Nuclear Experiment
Abstract: Precise knowledge of nuclear cross sections at stellar energies is of importance for cosmology as well as for nuclear astrophysics. Measuring these cross sections at the relevant energies is quite challenging not only for the extremely low cross sections involved but also because a lot of parameters like stopping powers and electron screening are not well known at low energies. The LUNA collaboration has installed a second high current accelerator of 400kV at the underground laboratory of Gran Sasso. It is dedicated to measure the cross section of charged particle induced nuclear reactions of astrophysical interest at energies far below the respective Coulomb barrier and possibly close or within the associated Gamow energy.
Published: 2003
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219. Charge state studies of low energy heavy ions passing through hydrogen and helium gas

Author: John D'Auria, Mario R. Romano, Gianluca Imbriani, L. Buchmann, A Olin, J. Rogers, W. Liu, A. Chen, D. A. Hutcheon, D. Hunter, Uwe Greife, Antonio D'Onofrio, Filippo Terrasi, S. Engel, Detlef Rogalla, Lucio Gialanella, D Ottewell, Ahmed Hussein, G. Roy, Liu, W, Imbriani, G, Buchmann, L, Chen, Aa, D'Auria, Jm, D'Onofrio, Antonio, Engel, S, Gialanella, Lucio, Greife, U, Hunter, D, Hussein, A, Hutcheon, Da, Olin, A, Ottewell, D, Rogalla, D, Rogers, J, Romano, M, Roy, G, Terrasi, Filippo, Liu, W., Imbriani, Gianluca, Buchmann, L., Chen, A. A., D'Auria, J. M., D'Onofrio, A., Engel, S., Gialanella, L., Greife, U., Hunter, D., Hussein, A., Hutcheon, D. A., Olin, A., Ottewell, D., Rogalla, D., Rogers, J., Romano, Mario, Roy, G., and Terrasi, F.
Subjects: Physics, Nuclear and High Energy Physics, Hydrogen, Helium gas, chemistry.chemical_element, Charge (physics), State (functional analysis), Experimental Nuclear Physics, Ion, Low energy, chemistry, Charge state distribution, Atomic physics, Nuclear Experiment, State distribution, Instrumentation, Beam energy
Abstract: Studies of the charge state distribution of low energy (< 1.5 MeV/u), low Z (< 13) heavy ions passing through hydrogen and helium gas of varying target pressure have been performed using separate windowless gas target systems at TRIUMF and the University of Naples. Semi-empirical relationships have been deduced to estimate the equilibrium charge state distributions as a function of beam energy. From these distributions, cross-sections for the relevant charge changing reactions have been deduced. (C) 2002 Elsevier Science B.V. All rights reserved.
Published: 2003
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220. A new setup for the underground study of capture reactions

Author: Gianluca Imbriani, Sandra Zavatarelli, Detlef Rogalla, P Cocconi, Joana V. Pinto, Carlo Broggini, B. Limata, F. Parodi, Daniel Bemmerer, A. Formicola, Gyuri Gyürky, Frank Strieder, A. Ordine, Antonio D'Onofrio, H. P. Trautvetter, Zsolt Fülöp, G. Gervino, C. Casella, A Loiano, M Parolin, C. Gustavino, Alberto Vomiero, P. Corvisiero, Lucio Gialanella, M. Junker, R. Bonetti, A. Rottura, Mario R. Romano, P. Musico, A. Lemut, J.P. Ribeiro, H. Costantini, L. Campajola, A. Guglielmetti, E. Somorjai, Vincenzo Roca, Filippo Terrasi, João Cruz, Paolo Prati, C. Rossi-Alvarez, A. P. Jesus, F. Schuemann, C. Rolfs, C., Casella, H., Costantini, A., Lemut, B., Limata, D., Bemmerer, R., Bonetti, C., Broggini, L., Campajola, P., Cocconi, P., Corvisiero, J., Cruz, A., D’Onofrio, A., Formicola, Z., Fülöp, G., Gervino, L., Gialanella, A., Guglielmetti, C., Gustavino, G., Gyurky, A., Loiano, Imbriani, Gianluca, A. P., Jesu, M., Junker, P., Musico, A., Ordine, F., Parodi, M., Parolin, J. V., Pinto, P., Prati, J. P., Ribeiro, Roca, Vincenzo, D., Rogalla, C., Rolf, Romano, Mario, C., Rossi Alvarez, A., Rottura, F., Schuemann, E., Somorjai, F., Strieder, F., Terrasi, H. P., Trautvetter, A., Vomiero, and S., Zavatarelli
Subjects: Nuclear physics, Physics, Nuclear and High Energy Physics, Measure (physics), Underground laboratory, Sensitivity (control systems), Instrumentation, Beam (structure)
Abstract: For the study of astrophysically relevant capture reactions in the underground laboratory LUNA a newsetup of high sensitivity has been implemented. The setup includes a windowless gas target, a 4p BGO summing crystal, and beam calorimeters. The setup has been recently used to measure the d(p,g) 3 He cross-section for the first time within its solar Gamowpeak, i.e. dow n to 2.5 keV c.m. energy. The features of the optimized setup are described. r 2002 Elsevier Science B.V. All rights reserved.
Published: 2002
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221. A new study of the22Ne(p, Î³)23Na reaction deep underground: Feasibility, setup and first observation of the 186 keV resonance

Author: P. Corvisiero, G. Gervino, Thomas Davinson, Rosanna Depalo, Douglas Scott, A. Formicola, C. Rossi Alvarez, C. Gustavino, M. Junker, C. G. Bruno, Gianluca Imbriani, Oscar Straniero, Marialuisa Aliotta, Davide Trezzi, Tamás Szücs, Paolo Prati, E. Somorjai, Antonio Caciolli, A. Guglielmetti, M. L. Menzel, Zs. Fülöp, Carlo Broggini, Daniel Bemmerer, Gy. Gyürky, A. Di Leva, R. Menegazzo, F. Cavanna, F. Ferraro, Frank Strieder, M. Anders, Z. Elekes, Cavanna, F, Depalo, R., Menzel, M. L., Aliotta, M., Anders, M., Bemmerer, D., Broggini, C., Bruno, C. G., Caciolli, A., Corvisiero, P., Davinson, T., DI LEVA, Antonino, Elekes, Z., Ferraro, F., Formicola, A., Fülöp, Z. s., Gervino, G., Guglielmetti, A., Gustavino, C., Gyürky, G. y., Imbriani, Gianluca, Junker, M., Menegazzo, R., Prati, P., Rossi Alvarez, C., Scott, D. A., Somorjai, E., Straniero, O., Strieder, F., Szücs, T., and Trezzi, D.
Subjects: Physics, Nuclear and High Energy Physics, Physics - Instrumentation and Detectors, Proton, Hydrogen, astrofisica nucleare, fisica, Resonance, chemistry.chemical_element, fisica underground, Nuclear physics, Neon, chemistry, fisica sperimentale, Astrophysics - Solar and Stellar Astrophysics, Nucleosynthesis, Nuclear astrophysics, Nuclear fusion, Nuclear Experiment, Beam (structure), Nuclear Physics
Abstract: The $^{22}$Ne(p,$\gamma$)$^{23}$Na reaction takes part in the neon-sodium cycle of hydrogen burning. This cycle is active in asymptotic giant branch stars as well as in novae and contributes to the nucleosythesis of neon and sodium isotopes. In order to reduce the uncertainties in the predicted nucleosynthesis yields, new experimental efforts to measure the $^{22}$Ne(p,$\gamma$)$^{23}$Na cross section directly at the astrophysically relevant energies are needed. In the present work, a feasibility study for a $^{22}$Ne(p,$\gamma$)$^{23}$Na experiment at the Laboratory for Underground Nuclear Astrophysics (LUNA) 400\,kV accelerator deep underground in the Gran Sasso laboratory, Italy, is reported. The ion beam induced $\gamma$-ray background has been studied. The feasibility study led to the first observation of the $E_{\rm p}$ = 186\,keV resonance in a direct experiment. An experimental lower limit of 0.12\,$\times$\,10$^{-6}$\,eV has been obtained for the resonance strength. Informed by the feasibility study, a dedicated experimental setup for the $^{22}$Ne(p,$\gamma$)$^{23}$Na experiment has been developed. The new setup has been characterized by a study of the temperature and pressure profiles. The beam heating effect that reduces the effective neon gas density due to the heating by the incident proton beam has been studied using the resonance scan technique, and the size of this effect has been determined for a neon gas target., Comment: Minor errors corrected; final version
Published: 2014

222. Absolute cross section of 7Be(p,γ)8B

Author: Uwe Greife, Zs. Fülöp, F. Schümann, L. Campajola, Antonio D'Onofrio, Gianluca Imbriani, C. Rolfs, Lucio Gialanella, Vincenzo Roca, P. Corvisiero, Paolo Prati, Frank Strieder, Sandra Zavatarelli, G. Gervino, Oscar Straniero, H. Costantini, A. Ordine, Filippo Terrasi, A. Formicola, E. Somorjai, Carlo Broggini, C. Gustavino, P. G. Prada Moroni, A. Guglielmetti, R. Bonetti, Gy. Gyürky, H. P. Trautvetter, M. Junker, Mario R. Romano, Detlef Rogalla, F., Strieder, L., Gialanella, G., Gyürky, F., Schümann, R., Bonetti, C., Broggini, L., Campajola, P., Corvisiero, H., Costantini, A., D'Onofrio, A., Formicola, Z., Fülöp, G., Gervino, U., Greife, A., Guglielmetti, C., Gustavino, Imbriani, Gianluca, M., Junker, P. G. P., Moroni, A., Ordine, P., Prati, Roca, Vincenzo, D., Rogalla, C., Rolf, Romano, Mario, E., Somorjai, O., Straniero, F., Terrasi, H. P., Trautvetter, and S., Zavatarelli
Subjects: Experimental Nuclear Physic, Physics, Nuclear reaction, Nuclear and High Energy Physics, Cross section (physics), Radiative capture, Zero-point energy, Nuclide, Atomic physics, Experimental Nuclear Astrophysic, Solar neutrino, Stellar hydrogen burning
Abstract: The absolute cross section σ ( E ) for the radiative capture reaction 7 Be(p, γ ) 8 B at the center-of-mass energies E =0.32 to 2.61 MeV has been measured using a 7 Be target deposited on a Cu backing and observing the β -delayed α -particles from 8 B. The backing causes a loss of less than 1% of the 8 B residual nuclides. The resulting astrophysical S ( E ) factor at zero energy, S (0)=18.4±1.6 eV b, is consistent only with a restricted data set from previous work.
Published: 2001
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223. The12C(α, γ)16O Reaction Rate and the Evolution of Stars in the Mass Range 0.8 ≤ M/M⊙ ≤ 25

Author: Gianluca Imbriani, Alessandro Chieffi, Lucio Gialanella, Oscar Straniero, Filippo Terrasi, Marco Limongi, Imbriani, Gianluca, Limongi, M., Gialanella, L, Terrasi, F., Straniero, O., and Chieffi, A.
Subjects: Convection, Physics, Range (particle radiation), Abundance (chemistry), Helium Burning in star, Astronomy and Astrophysics, Astrophysics, Reaction rate, Stars, Space and Planetary Science, Nuclear Astrophysics, Convective mixing, Astrophysics::Solar and Stellar Astrophysics, Stellar Evolution, Stellar evolution, Mass fraction, Astrophysics::Galaxy Astrophysics
Abstract: We discuss the influence of the C-12(alpha, gamma)O-16 reaction rate on the central He burning of stars in the mass range 0.8-25 M., as well as its effects on the explosive yields of a 25 M. star of solar chemical composition. We find that the central He burning is only marginally affected by a change in this cross section within the currently accepted uncertainty range. The only (important) quantity that varies significantly is the amount of C left by the He burning. Since the C-12(alpha, gamma)O-16 is efficient in a convective core, we have also analyzed the influence of the convective mixing in determining the final C abundance left by the central He burning. Our main finding is that the adopted mixing scheme does not influence the final C abundance provided the outer border of the convective core remains essentially fixed (in mass) when the central He abundance drops below similar or equal to0.1 dex by mass fraction; vice versa, even a slight shift (in mass) of the border of the convective core during the last part of the central He burning could appreciably alter the final C abundance. Hence, we stress that it is wiser to discuss the advanced evolutionary phases as a function of the C abundance left by the He burning rather than as a function of the efficiency of the C-12(alpha, gamma)O-16 reaction rate. Only a better knowledge of this cross section and/or the physics of the convective motions could help in removing the degeneracy between these two components. We also prolonged the evolution of the two 25 M. stellar models up to the core collapse and computed the Dnal explosive yields. Our main results are that the intermediate-light elements, Ne, Na, Mg, and Al (which are produced in the C convective shell), scale directly with the C abundance left by the He burning because they depend directly on the amount of available fuel (i.e., C and/or Ne). All the elements whose final yields are produced by any of the four explosive burnings (complete explosive Si burning, incomplete explosive Si burning, explosive O burning, and explosive Ne burning) scale inversely with the C abundance left by the He burning because the mass-radius relation in the deep interior of a star steepens as the C abundance reduces. We confirm previous findings according to which a low C abundance (similar or equal to0.2 dex by mass fraction) is required to obtain yields with a scaled solar distribution.
Published: 2001
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224. The E1 capture amplitude in 12C(α,γ0) 16O

Author: F. Strieder, Antonio D'Onofrio, A. Ordine, Marialuisa Aliotta, Filippo Terrasi, C. Agodi, Detlef Rogalla, G. Gyürki, L. Gialanella, E. Somorjai, Vincenzo Roca, L. Campajola, Gianluca Imbriani, P. Figuera, Mario R. Romano, H. P. Trautvetter, S. Theis, Uwe Greife, A. Del Zoppo, C. Rolfs, R. Alba, F. Schümann, Paolo Sapienza, Carlo Sabbarese, Gialanella, L., Rogalla, D., Strieder, F., Theis, S., Gyurki, G., Agodi, C., Alba, R., Aliotta, M., Campajola, L., Del Zoppo, A., D'Onofrio, A., Figuera, P., Greife, U., Imbriani, G., Ordine, A., Roca, V., Rolfs, C., Romano, M., Sabbarese, C., Sapienza, P., Schumann, F., Somorjai, E., Terrasi, F., Trautvetter, H. P., L., Gialanella, D., Rogalla, F., Strieder, S., Thei, G., Gyürki, C., Agodi, R., Alba, M., Aliotta, L., Campajola, A., Del Zoppo, A., D'Onofrio, P., Figuera, U., Greife, Imbriani, Gianluca, A., Ordine, Roca, Vincenzo, C., Rolf, Romano, Mario, C., Sabbarese, P., Sapienza, F., Schümann, E., Somorjai, F., Terrasi, and H. P., Trautvetter
Subjects: Physics, Excitation function, Nuclear and High Energy Physics, S-factor, Monte Carlo method, Detector, Hadron, Extrapolation, Nuclear physics, Helium burining, Amplitude, Nuclear fusion, Experimental nuclear physic, Nuclear Astrophysic
Abstract: An excitation function of the ground-state gamma (0)-ray capture transition in C-12(alpha, gamma)O-16 at theta (gamma) = 90 degrees was obtained in far geometry using six Ge detectors, where the study of the reaction was initiated in inverse kinematics involving a windowless gas target. The detectors observed predominantly the El capture amplitude. The data at E = 1.32 to 2.99 MeV lead to an extrapolated astrophysical S factor S-E1(E-0) = 90 +/- 15 keV b at E-0 = 0.3 MeV (for the case of constructive interference between the two lowest E1 sources), in good agreement with previous works. However, a novel Monte Carlo approach in the data extrapolation reveals systematic differences between the various data sets such that a combined analysis of all available data sets could produce a biased estimate of the S-E1(E-0) value. As a consequence, the case of destructive interference between the two lowest E1 sources with S-E1(E-0) = 8 +/- 3 keV b cannot be ruled out rigorously.
Published: 2001
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225. Influence of the 12C(α,γ)16O reaction rate on the evolution of a 15 M⊙ star

Author: Alessandro Chieffi, Gianluca Imbriani, Oscar Straniero, Filippo Terrasi, Marco Limongi, Imbriani, Gianluca, O., Straniero, F., Terrasi, M., Limongi, and A., Chieffi
Subjects: Reaction rate, Physics, Nuclear and High Energy Physics, Nuclear Astrophysics, Helium burning in Star, Astrophysics, Star (graph theory), Stellar Evolution
Abstract: In this paper we present the evolution of various 15M(circle dot) stellar models of solar and subsolar chemical composition, calculated using different values for the C-12(alpha, gamma)O-16 reaction rate. This process influences the evolution of a star because it directly operates during the helium burning and it determines the final abundances of (12)G and O-16 left by this burning. Since this reaction works in a convective environment an analysis of its influence on the evolution of a star cannot be disentangled by the behavior of the convective core. Indeed the final C-12 and O-16 abundances largely depend on a delicate balance between the efficiency of this rate and the treatment of the convective core. We will show some tests which indicate quantitavely this interplay.
Published: 2001
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226. A new measurement of the E1 amplitude in 12C(α,γ0)16O

Author: L. Gialanella, Antonio D'Onofrio, E. Somorjai, Paolo Sapienza, Detlef Rogalla, C. Spitaleri, Vincenzo Roca, Frank Strieder, S. Theis, Gianluca Imbriani, L. Campajola, H. P. Trautvetter, Gyuri Gyürky, Mario R. Romano, Uwe Greife, Marialuisa Aliotta, Filippo Terrasi, C. Agodi, F. Schümann, Carlo Sabbarese, C. Rolfs, R. Alba, P. Figuera, A. Del Zoppo, L., Gialanella, M., Aliotta, D., Rogalla, C., Rolf, F., Schümann, F., Strieder, S., Thei, H. P., Trautvetter, L., Campajola, Imbriani, Gianluca, Roca, Vincenzo, Romano, Mario, A., D'Onofrio, C., Sabbarese, F., Terrasi, C., Agodi, R., Alba, A., Del Zoppo, P., Figuera, P., Sapienza, C., Spitaleri, G., Gyurky, E., Somorjai, and U., Greife
Subjects: Experimental Nuclear Physic, Physics, Nuclear and High Energy Physics, Amplitude, Quantum electrodynamics, Helium burning in Stars, Nuclear Astrophysic
Abstract: The El amplitude of the transition to the ground state in the C-12(alpha, gamma)O-16 capture reaction was measured in the energy range E-cm=1.3 to 3.0 MeV using an intense C-12 beam in combination with a windowless He-4 gas target and an array of six 70% HPGe detectors. The detectors were placed in a ring-shaped geometry around the target at a distance of 17 cm on a plane perpendicular to the beam axis. A target length of 5.3 cm was defined by a 12.5 cm thick lead shielding. Passive and active shielding was used to achieve the necessary suppression of the beam induced and cosmic background. The results of this measurement and their extrapolation to the relevant energy during the helium burning phase in massive stars are reported.
Published: 2001
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227. Recoil separator ERNA: ion beam specifications

Author: C. Rolfs, Gianluca Imbriani, L. Gialanella, C. A. Barnes, A. Ordine, Vincenzo Roca, D. Schürmann, E. Fritz, Antonio D'Onofrio, L. Campajola, Mario R. Romano, F. Schümann, Carlo Sabbarese, Uwe Greife, H. P. Trautvetter, Detlef Rogalla, J. Ossmann, Frank Strieder, S. Theis, Marialuisa Aliotta, Filippo Terrasi, D., Rogalla, M., Aliotta, C. A., Barne, L., Campajola, A., D'Onofrio, E., Fritz, L., Gialanella, U., Greife, Imbriani, Gianluca, A., Ordine, J., Ossmann, Roca, Vincenzo, C., Rolf, Romano, Mario, C., Sabbarese, D., Schurmann, F., Schumann, F., Strieder, S., Thei, F., Terrasi, H. P., Trautvetter, D., Schürmann, and F., Schümann
Subjects: Experimental Nuclear Physic, Physics, Nuclear physics, Momentum, Nuclear and High Energy Physics, Wien filter, Ion beam, Dipole magnet, Magnet, Nuclear Astrophysics, Separator (oil production), Dynamitron, Beam (structure)
Abstract: For improved measurements of the key astrophysical reaction C-12(alpha, gamma)O-16 in inverted kinematics, a recoil separator ERNA is being developed at the 4 MV Dynamitron tandem accelerator in Bochum to detect directly the O-16 recoils with about 50% efficiency. Calculations of the ion beam optics including all filtering and focusing elements of ERNA are presented. Since the C-12 projectiles and the O-16 recoils have essentially the same momentum, and since the C-12 ion beam emerging from the accelerator passes through a momentum filter (analysing magnet), the C-12 ion beam must be as free as possible from O-16 contamination for ERNA to succeed. In the present work, the O-16 contamination was reduced from a level of 1 x 10(-11) to a level below 2 x 10(-29) by the installation of Wien filters both before and after the analysing magnet. The measurement of these and other beam specifications involved other parts of the final ERNA layout - sequentially a Wien filter, a 60 degrees dipole magnet, another Wien filter, and a Delta E-E telescope. The setup led to a measured suppression factor of 5 x 10(-18) for the C-12 ion beam. The experiments also indicate that an almost free choice of the charge state for the O-16 recoils is possible in the separator.
Published: 1999
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228. Change of the 7Be electron capture half-life in metallic environments

Author: Detlef Rogalla, Vincenzo Roca, A. P. Jesus, E. Somorjai, Antonio D'Onofrio, S. Yan, C. Rolfs, Zsolt Fülöp, D. Schürmann, Hans Werner Becker, N. De Cesare, Frank Strieder, Lucio Gialanella, Mario R. Romano, B. Limata, Gyuri Gyürky, F. Raiola, Gianluca Imbriani, Marialuisa Aliotta, Filippo Terrasi, João Cruz, J.P. Ribeiro, B. Wang, Wang, B., Yan, S., Limata, B., Raiola, F., Aliotta, M., Becker, H. W., Cruz, J., de Cesare, N., D'Onofrio, A., Fülöp, Z., Gialanella, L., Gyürky, G., Imbriani, Gianluca, Jesus, A., Ribeiro, J. P., Roca, Vincenzo, Rogalla, D., Rolfs, C., Romano, Mario, Schürmann, D., Somorjai, E., Strieder, F., and Terrasi, F.
Subjects: Free electron model, Physics, Nuclear and High Energy Physics, Condensed matter physics, Electron capture, Hadron, Insulator (electricity), Plasma, Electron, half-life 7Be, symbols.namesake, symbols, Nuclear fusion, Atomic physics, Debye
Abstract: For the electron capture of Be-7 in the metallic environments Pd and In the Be-7 half-life was observed to increase by 0.9 +/- 0.2 and 0.7 +/- 0.2%, respectively, while in the insulator Li2O it was unchanged within experimental error (all samples cooled to T = 12K). The observations are consistent with the predictions of the Debye plasma model applied to the quasi-free electrons in the metals.
Published: 2006
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229. A windowless hydrogen gas target for the measurement of 7Be(p,g)8B with the recoil separator ERNA

Author: Gianluca Imbriani, Antonio D'Onofrio, D. Schürmann, M. Romoli, N. De Cesare, A. Di Leva, Lucio Gialanella, Filippo Terrasi, M. De Cesare, Mario R. Romano, D., Schuermann, DI LEVA, Antonino, L., Gialanella, M., De Cesare, N., De Cesare, Imbriani, Gianluca, A., D'Onofrio, Romano, Mario, M., Romoli, and F., Terrasi
Subjects: Physics, Nuclear and High Energy Physics, Hydrogen, Physics::Instrumentation and Detectors, Hadron, windowless gas target, chemistry.chemical_element, Recoil separator, Characterization (materials science), Nuclear physics, Cross section (physics), chemistry, Experimental Nuclear Astrophysics, Nuclear fusion, Atomic physics, Nuclear Experiment
Abstract: A new measurement of the cross section of 7Be(p, $ \gamma$ )8B will be done in inverted kinematics with the recoil separator ERNA at the CIRCE laboratory in Caserta, Italy. The 8B recoils will be produced in a windowless hydrogen gas target. We report here on the construction and characterization of the gas cell. In detail we describe measurements for target density, the profile determination via the 7Li(p, p’)7Li* reaction as well as the role and performance of a gaseous post-stripper.
Published: 2013

230. Impact of a revised $^{25}$Mg(p,$\gamma$)$^{26}$Al reaction rate on the operation of the Mg-Al cycle

Author: Daniel Bemmerer, H. P. Trautvetter, Michele Marta, Gianluca Imbriani, Carlo Broggini, A. Lemut, Luciano Piersanti, H. Costantini, Oscar Straniero, Filippo Terrasi, Vincenzo Roca, Gyuri Gyürky, Frank Strieder, Paolo Prati, C. Mazzocchi, A. Guglielmetti, B. Limata, C. Gustavino, M. Junker, A. Formicola, Roberto Menegazzo, G. Gervino, C. Rolfs, C. Rossi Alvarez, Sergio Cristallo, Antonio Caciolli, E. Somorjai, Z. Elekes, P. Corvisiero, Zsolt Fülöp, A. DiLeva, O., Straniero, Imbriani, Gianluca, F., Strieder, D., Bemmerer, C., Broggini, A., Caciolli, P., Corvisiero, H., Costantini, S., Cristallo, DI LEVA, Antonino, A., Formicola, Z., Eleke, Fülöp, Z. s., G., Gervino, A., Guglielmetti, C., Gustavino, Gyürky, G. y., M., Junker, A., Lemut, B., Limata, M., Marta, C., Mazzocchi, R., Menegazzo, L., Piersanti, P., Prati, Roca, Vincenzo, C., Rolf, C., Rossi Alvarez, E., Somorjai, F., Terrasi, and H. P., Trautvetter
Subjects: Nuclear reaction, Proton, globular clusters: general, nuclear reactions, nucleosynthesis, abundances, stars: AGB and post-AGB, stars: WolfRayet, Astronomy and Astrophysics, Space and Planetary Science, astrofisica nucleare, Astrophysics, Evoluzione stellare, Chemical kinetics, Reaction rate, Nucleosynthesis, Nuclear astrophysics, Asymptotic giant branch, Nuclear Experiment, Physics, abundances, Presolar grains, Nuclear reactions, nucleosynthesis, abundances — Stars: AGB and post-AGB — Stars: Wolf-Rayet — globular clusters: general, Astrophysics - Astrophysics of Galaxies, Astrophysics - Solar and Stellar Astrophysics, Astrophysics - High Energy Astrophysical Phenomena
Abstract: Proton captures on Mg isotopes play an important role in the Mg-Al cycle active in stellar H-burning regions. In particular, low-energy nuclear resonances in the $^{25}$Mg(p,$\gamma$)$^{26}$Al reaction affect the production of radioactive $^{26}$Al$^{gs}$ as well as the resulting Mg/Al abundance ratio. Reliable estimations of these quantities require precise measurements of the strengths of low-energy resonances. Based on a new experimental study performed at LUNA, we provide revised rates of the $^{25}$Mg(p,$\gamma$)$^{26}$Al$^{gs}$ and the $^{25}$Mg(p,$\gamma$)$^{26}$Al$^{m}$ reactions with corresponding uncertainties. In the temperature range 50 to 150 MK, the new recommended rate of the $^{26}$Al$^{m}$ production is up to 5 times higher than previously assumed. In addition, at T$=100$ MK, the revised total reaction rate is a factor of 2 higher. Note that this is the range of temperature at which the Mg-Al cycle operates in an H-burning zone. The effects of this revision are discussed. Due to the significantly larger $^{25}$Mg(p,$\gamma$)$^{26}$Al$^{m}$ rate, the estimated production of $^{26}$Al$^{gs}$ in H-burning regions is less efficient than previously obtained. As a result, the new rates should imply a smaller contribution from Wolf-Rayet stars to the galactic $^{26}$Al budget. Similarly, we show that the AGB extra-mixing scenario does not appear able to explain the most extreme values of $^{26}$Al/$^{27}$Al, i.e. $>10^{-2}$, found in some O-rich presolar grains. Finally, the substantial increase of the total reaction rate makes the hypothesis of a self-pollution by massive AGBs a more robust explanation for the Mg-Al anticorrelation observed in Globular-Cluster stars.
Published: 2012

231. Proton capture on 17O and its astrophysical implications

Author: Manoel Couder, Ethan Uberseder, Joachim Görres, D. Schürmann, Q. Li, Edward Stech, G. Imbriani, Donald Robertson, A. Best, Richard deBoer, A. Kontos, Michael Wiescher, A., Konto, J., Görre, Best, Andrea, M., Couder, R., Deboer, Imbriani, Gianluca, Q., Li, D., Robertson, D., Schürmann, E., Stech, E., Uberseder, and M., Wiescher
Subjects: Physics, Experimental Nuclear Physic, Nuclear and High Energy Physics, Work (thermodynamics), Range (particle radiation), Proton, 010308 nuclear & particles physics, Resonance, FOS: Physical sciences, 7. Clean energy, 01 natural sciences, Lower energy, Nuclear physics, Reaction rate, Cross section (physics), 13. Climate action, Nucleosynthesis, 0103 physical sciences, Shell Hydrogen burning in stars, Nuclear Experiment (nucl-ex), 010306 general physics, Nuclear Astrophysic, Nuclear Experiment
Abstract: The reaction $^{17}$O$(p,\gamma)^{18}$F influences hydrogen-burning nucleosynthesis in several stellar sites, such as red giants, asymptotic giant branch (AGB) stars, massive stars and classical novae. In the relevant temperature range for these environments ($T_{9}=0.01-0.4), the main contributions to the rate of this reaction are the direct capture process, two low lying narrow resonances ($E_{r}=65.1$ and 183 keV) and the low-energy tails of two broad resonances ($E_{r}=557$ and 677 keV). Previous measurements and calculations give contradictory results for the direct capture contribution which in turn increases the uncertainty of the reaction rate. In addition, very few published cross section data exist for the high energy region that might affect the interpretation of the direct capture and the contributions of the broad resonances in the lower energy range. This work aims to address these issues. The reaction cross section was measured in a wide proton energy range ($E_{c.m.}=345$ - 1700 keV) and at several angles ($\theta_{lab}=0^{\circ},45^{\circ},90^{\circ},135^{\circ}$). The observed primary $\gamma$-transitions were used as input in an $R$-matrix code in order to obtain the contribution of the direct capture and the two broad resonances to the low-energy region. The extrapolated S-factor from the present data is in good agreement with the existing literature data in the low-energy region. A new reaction rate was calculated from the combined results of this work and literature S-factor determinations. Resonance strengths and branchings are reported for several $^{18}$F states. We were able to extrapolate the astrophysical S-factor of the reaction $^{17}$O$(p,\gamma)^{18}$F at low energies from cross section data taken at higher energies. No significant changes in the nucleosynthesis are expected from the newly calculated reaction rate., Comment: Accepted in Physical Review C
Published: 2012

232. The25Mg(p, Î³)26Al reaction at low astrophysical energies

Author: A. Best, M. Junker, Antonio Caciolli, E. Somorjai, C. Rolfs, A. Lemut, Z. Elekes, P. Corvisiero, C. Gustavino, Oscar Straniero, Frank Strieder, Gianluca Imbriani, Michele Marta, Filippo Terrasi, A. Formicola, C. Rossi Alvarez, Daniel Bemmerer, H. P. Trautvetter, Vincenzo Roca, A. DiLeva, Paolo Prati, Zsolt Fülöp, B. Limata, Roberto Menegazzo, Gyuri Gyürky, G. Gervino, A. Guglielmetti, H. Costantini, Carlo Broggini, C. Mazzocchi, F., Strieder, Limata, BENEDICTA NORMANNA, A., Formicola, Imbriani, Gianluca, M., Junker, D., Bemmerer, Best, Andrea, C., Broggini, A., Caciolli, P., Corvisiero, H., Costantini, DI LEVA, Antonino, Z., Eleke, Fülöp, Z. s., G., Gervino, A., Guglielmetti, C., Gustavino, Gyürky, G. y., A., Lemut, M., Marta, C., Mazzocchi, R., Menegazzo, P., Prati, Roca, Vincenzo, C., Rolf, C., Rossi Alvarez, E., Somorjai, O., Straniero, F., Terrasi, and H. P., Trautvetter
Subjects: Physics, Nuclear and High Energy Physics, Nuclear astrophysic, Physics::Instrumentation and Detectors, Astrophysics::High Energy Astrophysical Phenomena, Resolution (electron density), Resonance, Mg-Al cycle, Nuclear astrophysics, Proton-capture reaction, Reaction rate, Resonance strength, Crystal, Nuclear physics, Underground laboratory, High Energy Physics::Experiment, Atomic physics, Hpge detector, Nuclear Experiment
Abstract: In the present work we report on a new measurement of resonance strengths in the reaction 25Mg(p,gamma)26Al at E_cm= 92 and 189 keV. This study was performed at the LUNA facility in the Gran Sasso underground laboratory using a 4pi BGO summing crystal. For the first time the 92 keV resonance was directly observed and a resonance strength omega-gamma=(2.9+/-0.6)x10E-10 eV was determined. Additionally, the gamma-ray branchings and strength of the 189 keV resonance were studied with a high resolution HPGe detector yielding an omega-gamma value in agreement with the BGO measurement, but 20% larger compared to previous works.
Published: 2012

233. Preparation and characterisation of isotopically enriched Ta2O5 targets for nuclear astrophysics studies

Author: Gianluca Imbriani, Tamás Szücs, H. P. Trautvetter, Oscar Straniero, Marialuisa Aliotta, Filippo Terrasi, M. Marta, G. Gervino, C. Rolfs, A. Formicola, A. Guglielmetti, Zs. Fülöp, Carlo Broggini, M. Campeggio, Gy. Gyürky, Enrico Napolitani, C. Salvo, Frank Strieder, C. Gustavino, R. Menegazzo, V. Rigato, Vincenzo Roca, Paolo Prati, Daniel Bemmerer, M. Anders, C. Rossi Alvarez, Rosanna Depalo, Antonio Caciolli, E. Somorjai, Z. Elekes, P. Corvisiero, Davide Trezzi, Douglas Scott, A. Bellini, A. Di Leva, M. Junker, A., Caciolli, D. A., Scott, A., Di Leva, A., Formicola, M., Aliotta, M., Ander, A., Bellini, D., Bemmerer, C., Broggini, M., Campeggio, P., Corvisiero, R., Depalo, Z., Eleke, Z., Fülöp, G., Gervino, A., Guglielmetti, C., Gustavino, G., Gyürky, G., Imbriani, M., Junker, M., Marta, R., Menegazzo, E., Napolitani, P., Prati, V., Rigato, V., Roca, C., Rolf, C., Rossi Alvarez, E., Somorjai, C., Salvo, O., Straniero, F., Strieder, T., Szüc, Terrasi, Filippo, H. P., Trautvetter, D., Trezzi, DI LEVA, Antonino, Fülöp, Z. s., Gyürky, G. y., Imbriani, Gianluca, Roca, Vincenzo, and F., Terrasi
Subjects: Physics, Nuclear and High Energy Physics, stellar evolution, Proton, nuclear astrophysics, Radiochemistry, Tantalum, FOS: Physical sciences, chemistry.chemical_element, Isotopic composition, chemistry, nuclear physics, Nuclear astrophysics, Special care, Nuclear Experiment (nucl-ex), Nuclear Experiment, Stoichiometry, Beam (structure)
Abstract: The direct measurement of reaction cross sections at astrophysical energies often requires the use of solid targets of known thickness, isotopic composition, and stoichiometry that are able to withstand high beam currents for extended periods of time. Here, we report on the production and characterisation of isotopically enriched Ta$_2$O$_5$ targets for the study of proton-induced reactions at the Laboratory for Underground Nuclear Astrophysics facility of the Laboratori Nazionali del Gran Sasso. The targets were prepared by anodisation of tantalum backings in enriched water (up to 66% in $^{17}$O and up to 96% in $^{18}$O). Special care was devoted to minimising the presence of any contaminants that could induce unwanted background reactions with the beam in the energy region of astrophysical interest. Results from target characterisation measurements are reported, and the conclusions for proton capture measurements with these targets are drawn., accepted to EPJA
Published: 2012
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234. Elastic scattering of protons from 15N

Author: Ethan Uberseder, P. J. LeBlanc, Michael Wiescher, S. O'Brien, S. Falahat, Richard deBoer, G. Imbriani, Joachim Görres, R., Deboer, P., Leblanc, S., Falahat, Imbriani, Gianluca, J., Görre, S., O’Brien, E., Uberseder, and M., Wiescher
Subjects: Elastic scattering, Physics, Nuclear and High Energy Physics, Proton, Order (ring theory), Nuclear reaction, CNO cycle, Excited state, Yield ratio, Atomic physics, Experimental nuclear physic, Energy (signal processing), Excitation, Spin-½
Abstract: Background: Resonances observed through elastic scattering of protons on ${}^{15}$N can provide information about the partial widths, spin parities, and energies of excited states in ${}^{16}$O near the proton separation energy. This is the same energy region important for the nuclear astrophysics reactions ${}^{15}$N${(p,\ensuremath{\gamma})}^{16}$O and ${}^{15}$N${(p,\ensuremath{\alpha})}^{12}$C. While previous measurements have been made, they are limited in scope, especially in their angular coverage. Purpose: Obtain additional ${}^{15}$N${(p,p)}^{15}$N reaction data which can be used in a global multiple-channel $R$-matrix analysis of the ${}^{16}$O compound nucleus in order to better constrain the level parameters of states which contribute to the reaction ${}^{15}$N${(p,\ensuremath{\gamma})}^{16}$O. Methods: Measure the excitation functions of ${}^{15}$N${(p,p)}^{15}$N over an energy range from ${E}_{p}$ $=$ 0.6 to 1.8 MeV at laboratory angles of 90${}^{\ensuremath{\circ}}$, 105${}^{\ensuremath{\circ}}$, 135${}^{\ensuremath{\circ}}$, 150${}^{\ensuremath{\circ}}$, and 165${}^{\ensuremath{\circ}}$. The reaction ${}^{15}$N${(p,{\ensuremath{\alpha}}_{0})}^{12}$C was measured concurrently. Results: Ratios of the excitation functions were extracted from the yield data. Resonances were identified in the yield ratio data which correspond to previously reported levels in ${}^{16}$O. An $R$-matrix analysis, which fits the present data as well as previous measurements from the literature simultaneously, finds reasonable agreement between the current measurements and those in the literature. Conclusions: The additional data from this measurement will be combined with previous literature data in a comprehensive $R$-matrix analysis of reactions which populate ${}^{16}$O over a similar energy region.
Published: 2012

235. Direct measurements of cross section of astrophysical interest

Author: Luna collaborations, Erna, Gianluca Imbriani, and Imbriani, Gianluca
Subjects: Nuclear reaction, Physics, History, Range (particle radiation), Experimental approache, Cross section, Cosmic ray, Computer Science Applications, Education, Nuclear physics, Cross section (physics), Recoil, Nucleosynthesis, Recoil mass separator, Direct measurement, Limit (mathematics), Nuclear Experiment, Focus (optics)
Abstract: New direct experimental methods and techniques, combined with the development of new theoretical tools have opened new avenues to explore nuclear reactions of significance for nucleosynthesis at or near the actual temperatures of stellar burning. The main difficulty of direct measurements is determined by the background, which, together with the low cross sections, set a limit on the energy range that can be investigated with a simple setup on the earth's surface. Essentially there are three sources of background, cosmic rays, environmental radioactivity and beam-target induced nuclear reactions. Each of these sources produces background of a different nature and energy, so that each reaction studied needs special care to suppress the relevant background component. I will show different experimental approaches that have been used to study processes of astrophysical interest. In particular, I will focus my attention on underground experiments and the recoil mass separator approach.
Published: 2011

236. Revision of the 15N(p, γ)16O reaction rate and oxygen abundance in H-burning zones

Author: Gianluca Imbriani, G. Gervino, A. Formicola, Zs. Fülöp, C. Rolfs, V. Capogrosso, Oscar Straniero, Filippo Terrasi, Alberto Vomiero, Antonio Caciolli, E. Somorjai, Gy. Gyürky, H. P. Trautvetter, Z. Elekes, A. Guglielmetti, Carlo Broggini, Frank Strieder, C. Gustavino, H. Costantini, Sara Palmerini, P. Corvisiero, C. Mazzocchi, M. Marta, Vincenzo Roca, Paolo Prati, M. Junker, A. Lemut, R. Menegazzo, C. Rossi Alvarez, Daniel Bemmerer, Caciolli, A., Mazzocchi, C., Capogrosso, V., Bemmere, D., Broggini, C., Corvisiero, P., Costantini, H., Elekes, Z., Formicola, A., Fülöp, Z., Gervino, G., Guglielmetti, A., Gustavino, C., Gyürky, G., Imbriani, Gianluca, Junker, M., Lemut, A., Marta, M., Menegazzo, R., Palmerini, S., Prati, P., Roca, Vincenzo, Rolfs, C., Rossi Alvarez, C, Somorjai, E., Straniero, O., Strieder, F., Terrasi, F., Trautvetter, H. P., and Vomiero, A.
Subjects: Cataclysmic variables, Novae, Nuclear reaction, abundances, Stars: AGB and post-AGB, Population, nuclear astrophysics, CNO Cycle, Astrophysics, 01 natural sciences, Reaction rate, Nucleosynthesis, 0103 physical sciences, Asymptotic giant branch, education, Novae, Nuclear Experiment, 010303 astronomy & astrophysics, Cataclysmic variables, Physics, education.field_of_study, abundances, 010308 nuclear & particles physics, Nuclear reactions, nucleosynthesis, abundances, Stars: AGB and post-AGB, Astronomy and Astrophysics, Space and Planetary Science, nucleosynthesis, Giant star, Red-giant branch, Stars, Astrophysics - Solar and Stellar Astrophysics, nucleosynthesi, 13. Climate action, Globular cluster, Nuclear reactions
Abstract: The NO cycle takes place in the deepest layer of a H-burning core or shell, when the temperature exceeds T {\simeq} 30 {\cdot} 106 K. The O depletion observed in some globular cluster giant stars, always associated with a Na enhancement, may be due to either a deep mixing during the RGB (red giant branch) phase of the star or to the pollution of the primordial gas by an early population of massive AGB (asymptotic giant branch) stars, whose chemical composition was modified by the hot bottom burning. In both cases, the NO cycle is responsible for the O depletion. The activation of this cycle depends on the rate of the 15N(p,{\gamma})16O reaction. A precise evaluation of this reaction rate at temperatures as low as experienced in H-burning zones in stellar interiors is mandatory to understand the observed O abundances. We present a new measurement of the 15N(p,{\gamma})16O reaction performed at LUNA covering for the first time the center of mass energy range 70-370 keV, which corresponds to stellar temperatures between 65 {\cdot} 106 K and 780 {\cdot}106 K. This range includes the 15N(p,{\gamma})16O Gamow-peak energy of explosive H-burning taking place in the external layer of a nova and the one of the hot bottom burning (HBB) nucleosynthesis occurring in massive AGB stars. With the present data, we are also able to confirm the result of the previous R-matrix extrapolation. In particular, in the temperature range of astrophysical interest, the new rate is about a factor of 2 smaller than reported in the widely adopted compilation of reaction rates (NACRE or CF88) and the uncertainty is now reduced down to the 10% level., Comment: 6 pages, 5 figures
Published: 2011

237. Recoil separator ERNA: improved measurements of the astrophysical key reaction 12C(α,γ)16O

Author: Gianluca Imbriani, H. P. Trautvetter, L. Campajola, Lucio Gialanella, Vincenzo Roca, C. Rolfs, Frank Strieder, Uwe Greife, Mario R. Romano, Detlef Rogalla, Marialuisa Aliotta, Filippo Terrasi, A. Ordine, S. Theis, C. A. Barnes, Antonio D'Onofrio, F. Schümann, Carlo Sabbarese, D. Schürmann, D., Rogalla, M., Aliotta, C. A., Barne, L., Campajola, A., D'Onofrio, L., Gialanella, U., Greife, Imbriani, Gianluca, A., Ordine, Roca, Vincenzo, C., Rolf, Romano, Mario, C., Sabbarese, D., Schürmann, F., Schümann, F., Strieder, S., Thei, F., Terrasi, and H. P., Trautvetter
Subjects: Experimental Nuclear Physic, Physics, Nuclear physics, Nuclear and High Energy Physics, Range (particle radiation), Nuclear Astrophysics, Nuclear astrophysics, Atomic physics, Tandem accelerator, Nuclear Experiment, Dynamitron, Recoil separator
Abstract: The recoil separator ERNA (European Recoil Separator for Nuclear Astrophysics) for improved measurements of the astrophysical key reaction C-12(alpha, gamma)O-16 is being developed at the 4 MV Dynamitron tandem accelerator in Bochum to detect directly the O-16 recoils. The total detection efficiency of about 50 % allows direct measurements in a much wider energy range than previously accessible. In addition this technique allows improved measurements not hampered by cosmic background problems when compared to gamma -ray detection.
Published: 2001
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238. Constraining the S-factor of 15N(p,g)16O at Astrophysical Energies

Author: Leblanc, P. J., Imbriani, G., Gorres, G., Junker, M., Azuma, R., Beard, M., Bemmerer, D., Best, A., Broggini, C., Caciolli, A., Corvisiero, P., Costantini, H., Couder, M., Deboer, R., Elekes, Z., Falahat, S., Formicola, A., Fulop, Z. s., Gervino, Gianpiero, Guglielmetti, A., Gustavino, C., Gyurky, G. y., Kappeler, F., Kontos, A., Kuntz, R., Leiste, H., Lemut, A., Li, Q., Limata, B., Marta, M., Mazzocchi, C., Menegazzo, R., O'Brien, S., Palumbo, A., Prati, P., Roca, V., Rolfs, C., Rossi Alvarez, C., Samorjai, E., Stech, E., Straniero, O., Strieder, F., Tan, W., Terrasi, F., Trautvetter, H. P., Uberseder, E., Wiescher, M., Leblanc, P. J., Imbriani, Gianluca, Görres, J, Junker, M., Azuma, R., Beard, M., Bemmerer, D., Best, Andrea, Broggini, C, Caciolli, A, Corvisiero, P., Costantini, H., Couder, M., Deboer, R., 1 Elekes, Z., Falahat, S., Formicola, A., Fülp, Z, Gervino, G., Guglielmetti, A., Gustavino, C., Gyürky, G. y., Käppeler, K., Kontos, A., Kuntz, R., Leiste, H., Lemut, A., Li, Q., Limata, B., Marta, M., Mazzocchi, C., Menegazzo, R., O'Brien, S., Palumbo, A., Prati, P., Roca, Vincenzo, Rolfs, C., Rossi Alvarez, C., Somorjai, E., Stech, E., Straniero, O., Strieder, F., Tan, W., Terrasi, F., Trautvetter, H. P., Uberseder, E., and Wiescher, M.
Subjects: Experimental Nuclear Physic, Astrophysics::High Energy Astrophysical Phenomena, Radiative capture, FOS: Physical sciences, Nuclear Experiment (nucl-ex), Nuclear Astrophysic, Nuclear Experiment, Stellar hydrogen burning
Abstract: The 15N(p,g)16O reaction represents a break out reaction linking the first and second cycle of the CNO cycles redistributing the carbon and nitrogen abundances into the oxygen range. The reaction is dominated by two broad resonances at Ep = 338 keV and 1028 keV and a Direct Capture contribution to the ground state of 16O. Interference effects between these contributions in both the low energy region (Ep < 338 keV) and in between the two resonances (338, Comment: 15 pages, 9 figures
Published: 2010

239. Low energy beam induced background studies for a 12C(12C,p)23Na reaction cross section measurement

Author: Zickefoose, J., Schweitzer, J., Spillane, T., Strieder, F., Becker, H. -W, Rolfs, C., Di Leva, A., Cesare, M., Cesare, N., Filippo Terrasi, Gialanella, L., Schürmann, D., Guan, Y., Imbriani, G., Limata, B., James, Zickefoose, Jeffrey, Schweitzer, Timothy, Spillane, Frank, Strieder, Hans Werner, Becker, Claus, Rolf, DI LEVA, Antonino, Mario De, Cesare, Nicola De, Cesare, Filippo, Terrasi, Lucio, Gialanella, Daniel, Schürmann, Yongjing, Guan, Imbriani, Gianluca, and Benedicta, Limata
Abstract: The cross section of 12C+12C fusion reactions determines the conditions of carbon ignition in stars. The presence of structures, which are likely to extend to low energies, makes the extrapolation of data collected at high energy to the stellar energy difficult and potentially inaccurate, so a direct measurement is desirable. Here we report on an extremely improbable two-step background process which prohibits the measurement of the 12C(12C,p)23Na carbon fusion reaction at low energies in the presence of deuterium contamination. It appears that with a modified setup and selected targets reliable measurements down to Ecm=2.0 MeV are possible.
Published: 2010

240. An actively vetoed Clover γ-detector for nuclear astrophysicsat LUNA

Author: Luna, Collaboration, Szucs, T., Bemmerer, D., Broggini, C., Caciolli, A., Confortola, F., Corvisiero, P., Elekes, Z., Formicola, A., Fulop, Zs, Gervino, G., Guglielmetti, A., Gustavino, C., Gyurky, Gy, Imbriani, G., Junker, M., Lemut, A., Marta, M., Mazzocchi, C., Menegazzo, R., Prati, P., Roca, V., Rolfs, C., Rossi Alvarez, C., Somorjai, E., Oscar Straniero, Strieder, F., Terrasi, F., Trautvetter, H. P., T., Szuc, D., Bemmerer, C., Broggini, A., Caciolli, F., Confortola, P., Corvisiero, Z., Eleke, A., Formicola, F¨ul¨op, Z. s., G., Gervino, A., Guglielmetti, C., Gustavino, Gy¨urky, G. y., Imbriani, Gianluca, M., Junker, A., Lemut, M., Marta, C., Mazzocchi, R., Menegazzo, P., Prati, Roca, Vincenzo, C., Rolf, C., Rossi Alvarez, E., Somorjai, O., Straniero, F., Strieder, F., Terrasi, and H. P., Trautvetter
Subjects: Physics, Nuclear and High Energy Physics, Clover type HP Germaniun detector, Physics::Instrumentation and Detectors, Detector, Astrophysics::Instrumentation and Methods for Astrophysics, FOS: Physical sciences, Underground Laboratories, Semiconductor detector, Nuclear physics, Nuclear astrophysics, High Energy Physics::Experiment, Nuclear Experiment (nucl-ex), Nuclear Experiment, Nuclear Astrophysic
Abstract: An escape-suppressed, composite high-purity germanium detector of the Clover type has been installed at the Laboratory for Underground Nuclear Astrophysics (LUNA) facility, deep underground in the Gran Sasso Laboratory, Italy. The laboratory gamma-ray background of the Clover detector has been studied underground at LUNA and, for comparison, also in an overground laboratory. Spectra have been recorded both for the single segments and for the virtual detector formed by online addition of all four segments. The effect of the escape-suppression shield has been studied as well. Despite their generally higher intrinsic background, escape-suppressed detectors are found to be well suited for underground nuclear astrophysics studies. As an example for the advantage of using a composite detector deep underground, the weak ground state branching of the Ep = 223 keV resonance in the 24Mg(p,gamma)25Al reaction is determined with improved precision., 8 pages, 6 figures, 3 tables; as accepted by Eur. Phys. J. A
Published: 2010

241. Solar fusion cross sections II: the pp chain and CNO cycles

Author: Rocco Schiavilla, Gianluca Imbriani, Wick Haxton, Alejandro Garcia, H. Costantini, Michael J. Ramsey-Musolf, K. Langanke, Barry Davids, Ethan Uberseder, Filomena Nunes, Daniel Bemmerer, R. E. Tribble, Daniela Leitner, Moshe Gai, K. A. Snover, Paolo Prati, H. P. Trautvetter, Frank Strieder, Laura Elisa Marcucci, Arnd R. Junghans, R. G. Hamish Robertson, Kenneth M. Nollett, Kuniharu Kubodera, Claudio Spitaleri, Jiunn-Wei Chen, Michael Wiescher, Takahisa Itahashi, T. Motobayashi, Richard H. Cyburt, P. D. Parker, Edward Simpson, Matthaeus Leitner, Uwe Greife, Stuart Freedman, K. M. Heeger, K. Suemmerer, Stefan Typel, T.-S. Park, L. Winslow, A. M. Mukhamedzhanov, L. Gialanella, Michael Hass, A. B. Balantekin, Paul Vetter, Eric Adelberger, D. Gazit, Manoel Couder, Carlos A. Bertulani, Adelberger, E. G., Garcia, A., Robertson, R. G. H., Snover, K. A., Balantekin, A. B., Heeger, K., Ramsey Musolf, M. J., Bemmerer, D., Junghans, A., Bertulani, C. A., Chen, J. W., Costantini, H., Prati, P., Couder, M., Uberseder, E., Wiescher, M., Cyburt, R., Davids, B., Freedman, S. J., Gai, M., Gazit, D., Gialanella, L., Imbriani, Gianluca, Greife, U., Hass, M., Haxton, W. C., Itahashi, T., Kubodera, K., Langanke, K., Leitner, D., Leitner, M., Vetter, P., Winslow, L., Marcucci, L. E., Motobayashi, T., Mukhamedzhanov, A, Tribble, R. E., Nollett, K. M., Nunes, F. M., Park, T. S., Parker, P. D., Schiavilla, R., Simpson, E. C., Spitaleri, C., Strieder, F., Trautvetter, H. P., Suemmerer, K., Typel, S., Adelberger, Eg, Garcia, A, Robertson, Rgh, Snover, Ka, Balantekin, Ab, Heeger, K, Ramsey Musolf, Mj, Bemmerer, D, Junghans, A, Bertulani, Ca, Chen, Jw, Costantini, H, Prati, P, Couder, M, Uberseder, E, Wiescher, M, Cyburt, R, Davids, B, Freedman, Sj, Gai, M, Gazit, D, Gialanella, Lucio, Imbriani, G, Greife, U, Hass, M, Haxton, Wc, Itahashi, T, Kubodera, K, Langanke, K, Leitner, D, Leitner, M, Vetter, P, Winslow, L, Marcucci, Le, Motobayashi, T, Tribble, Re, Nollett, Km, Nunes, Fm, Park, T, Parker, Pd, Schiavilla, R, Simpson, Ec, Spitaleri, C, Strieder, F, Trautvetter, Hp, and Suemmerer, K
Subjects: Evoluzione Stellare, CNO cycle, astro-ph.SR, nucl-th, Nuclear Theory, Solar neutrino, Fluids & Plasmas, FOS: Physical sciences, General Physics and Astronomy, nucl-ex, High Energy Physics - Experiment, Nuclear Theory (nucl-th), Nuclear physics, High Energy Physics - Experiment (hep-ex), Affordable and Clean Energy, Solar core, Nucleosintesi Stellare, Nuclear fusion, Nuclear Experiment (nucl-ex), Nuclear Experiment, Solar and Stellar Astrophysics (astro-ph.SR), Fisica Nucleare Sperimentale, Physics, Proton–proton chain reaction, Astrofisica Nucleare, business.industry, hep-ex, Solar energy, Stars, Electricity generation, Astrophysics - Solar and Stellar Astrophysics, Physical Sciences, business
Abstract: We summarize and critically evaluate the available data on nuclear fusion cross sections important to energy generation in the Sun and other hydrogen-burning stars and to solar neutrino production. Recommended values and uncertainties are provided for key cross sections, and a recommended spectrum is given for 8B solar neutrinos. We also discuss opportunities for further increasing the precision of key rates, including new facilities, new experimental techniques, and improvements in theory. This review, which summarizes the conclusions of a workshop held at the Institute for Nuclear Theory, Seattle, in January 2009, is intended as a 10-year update and supplement to Reviews of Modern Physics 70 (1998) 1265., 54 pages, 20 figures, version to be published in Reviews of Modern Physics; various typos corrected and several updates made
Published: 2010
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242. Absolute cross section of p(7Be,γ)8B using a novel approach

Author: C. Rolfs, A. Ordine, Gianluca Imbriani, Gyuri Gyürky, Filippo Terrasi, Antonio D'Onofrio, Mario R. Romano, E. Somorjai, Lucio Gialanella, Carlo Sabbarese, H. P. Trautvetter, L. Campajola, Detlef Rogalla, Uwe Greife, Vincenzo Roca, Frank Strieder, G. Oliviero, L., Gialanella, F., Strieder, L., Campajola, A., D'Onofrio, U., Greife, G., Gyurky, Imbriani, Gianluca, G., Oliviero, A., Ordine, Roca, Vincenzo, C., Rolf, Romano, Mario, D., Rogalla, C., Sabbarese, E., Somorjai, F., Terrasi, H. P., Trautvetter, Gialanella, L., Strieder, F., Campajola, L., D'Onofrio, A., Greife, U., Gyurky, G., Imbriani, G., Oliviero, G., Ordine, A., Roca, V., Rolfs, C., Romano, M., Rogalla, D., Sabbarese, C., Somorjai, E., Terrasi, F., and Trautvetter, H. P.
Subjects: Physics, Elastic scattering, Nuclear and High Energy Physics, Ion beam, Experimental Nuclear physic, Solar neutrinos, Nuclear physics, Momentum, symbols.namesake, Cross section (physics), Yield (chemistry), symbols, Nuclear fusion, Nuclear Astrphysic, Rutherford scattering, Nuclide, Atomic physics
Abstract: The absolute cross section sigma(E) of the radiative capture reaction p(Be-7,gamma)B-8 at the center-of mass energy E = 992 keV has been measured using a radioactive 7Be ion beam and a windowless gas target system filled with H-2 gas. The B-8 residual nuclides were detected with a recoil separator consisting of momentum and velocity filters and a BE E detector telescope. The B-8 yield was observed concurrently with the Be-7+p elastic scattering yield, relating sigma(E) to the Rutherford scattering cross section. The resulting value, sigma(E) = 0.41+/-0.11 mu b, leads to an S(E) factor at zero energy of S(0) = 16+/-4 eV b, in fair agreement with recommended values.
Published: 2000
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243. Ultra-sensitive in-beam gamma-ray spectroscopy for nuclear astrophysics at LUNA

Author: M. Junker, R. Bonetti, A. Lemut, A. Formicola, Matthias Laubenstein, Z. Elekes, M. Marta, C. Rolfs, C. Gustavino, Gianluca Imbriani, Vincenzo Roca, P. Corvisiero, C. Rossi Alvarez, C. Mazzocchi, Paolo Prati, H. Costantini, B. Limata, Daniel Bemmerer, Carlo Broggini, Zs. Fülöp, Gy. Gyürky, G. Gervino, Antonio Caciolli, E. Somorjai, Oscar Straniero, Frank Strieder, Filippo Terrasi, A. Guglielmetti, R. Menegazzo, L. Agostino, F. Confortola, H. P. Trautvetter, A., Caciolli, L., Agostino, D., Bemmerer, R., Bonetti, C., Broggini, F., Confortola, P., Corvisiero, H., Costantini, Z., Eleke, A., Formicola, Fulop, Z. S., G., Gervino, A., Guglielmetti, C., Gustavino, Gyurky, G. Y., G., Imbriani, M., Junker, M., Laubenstein, A., Lemut, B., Limata, M., Marta, C., Mazzocchi, R., Menegazzo, P., Prati, V., Roca, C., Rolf, C., ROSSI ALVAREZ, E., Somorjai, O., Straniero, F., Strieder, Terrasi, Filippo, H. P., Trautvetter, Caciolli, A., Agostino, L., Bemmerer, D., Bonetti, R., Broggini, C., Confortola, F., Corvisiero, P., Costantini, H., Elekes, Z., Formicola, A., Fulop, Z. s., Gervino, G., Guglielmetti, A., Gustavino, C., Gyurky, G. y., Imbriani, Gianluca, Junker, M., Laubenstein, M., Lemut, A., Limata, B., Marta, M., Mazzocchi, C., Menegazzo, R., Prati, P., Roca, Vincenzo, Rolfs, C., Rossi Alvarez, C., Somorjai, E., Straniero, O., Strieder, F., Terrasi, F., and Trautvetter, H. P.
Subjects: Physics, Nuclear and High Energy Physics, Physics::Instrumentation and Detectors, Astrophysics::High Energy Astrophysical Phenomena, Astrophysics::Instrumentation and Methods for Astrophysics, FOS: Physical sciences, 3H, 3He, complex mixtures, and 4He-induced reactions, Nuclear physics, Nuclear physic, Nuclear astrophysics, γ-ray spectroscopy, Physics::Accelerator Physics, Gamma spectroscopy, Nuclear Experiment (nucl-ex), Spectroscopy, Nuclear Experiment, Beam (structure), Ultra sensitive
Abstract: Ultra-sensitive in-beam gamma-ray spectroscopy studies for nuclear astrophysics are performed at the LUNA (Laboratory for Underground Nuclear Astrophysics) 400 kV accelerator, deep underground in Italy's Gran Sasso laboratory. By virtue of a specially constructed passive shield, the laboratory gamma-ray background for E_\gamma < 3 MeV at LUNA has been reduced to levels comparable to those experienced in dedicated offline underground gamma-counting setups. The gamma-ray background induced by an incident alpha-beam has been studied. The data are used to evaluate the feasibility of sensitive in-beam experiments at LUNA and, by extension, at similar proposed facilities., Comment: accepted, Eur. Phys. J. A
Published: 2009

244. Ground state capture in 14N(p,γ)15O studied above the 259 keV resonance at LUNA

Author: A. Guglielmetti, Zs. Fülöp, Daniel Bemmerer, C. Rossi Alvarez, Carlo Broggini, Antonio Caciolli, E. Somorjai, B. Limata, C. Gustavino, A. Formicola, M. Marta, R. Menegazzo, F. Confortola, G. Gervino, H. Costantini, C. Mazzocchi, Alberto Vomiero, Gianluca Imbriani, R. Bonetti, Oscar Straniero, H. P. Trautvetter, Vincenzo Roca, Paolo Prati, Filippo Terrasi, Z. Elekes, P. Corvisiero, M. Junker, A. Lemut, C. Rolfs, Frank Strieder, Gy. Gyürky, S. Vezzu, H. P., Trautvetter, D., Bemmerer, R., Bonetti, C., Broggini, A., Caciolli, F., Confortola, P., Corvisiero, H., Costantini, Z., Eleke, A., Formicola, Z., Fulop, G., Gervino, A., Guglielmetti, G., Gyurky, C., Gustavino, G., Imbriani, M., Junker, A., Lemut, B., Limata, M., Marta, C., Mazzocchi, R., Menegazzo, P., Prati, V., Roca, C., Rolf, C., ROSSI ALVAREZ, E., Somorjai, O., Straniero, F., Strieder, Terrasi, Filippo, S., Vezzu, A., Vomiero, Zs, Fäuläop, Gy, Gyäurky, Imbriani, Gianluca, Limata, BENEDICTA NORMANNA, Roca, Vincenzo, C., Rossi Alvarez, F., Terrasi, and S., Vezzù
Subjects: Nuclear physics, Physics, Nuclear and High Energy Physics, Astrophysics::High Energy Astrophysical Phenomena, Detector, Resonance, CNO cycle, Clover-type gamma detector, Ground state, underground laboratory, Nuclear Experiment, Coincidence
Abstract: We report on a new measurement of $^{14}$N(p,$\gamma$)$^{15}$O for the ground state capture transition at $E_p$ = 360, 380 and 400 keV, using the 400 kV LUNA accelerator. The true coincidence summing effect --the major source of error in the ground state capture determination-- has been significantly reduced by using a Clover--type gamma detector., Comment: 6 pages, 5 figures, Accepted for publication in Journal of Physics G
Published: 2008

245. Comparison of the LUNA 3He(α,γ)7Be activation results with earlier measurements and model calculations

Author: H. Costantini, F. Confortola, Daniel Bemmerer, A. Formicola, R. Bonetti, Z. Elekes, A. Guglielmetti, M. Laubenstein, Carlo Broggini, Oscar Straniero, Gianluca Imbriani, Filippo Terrasi, M. Junker, A. Lemut, V. Lozza, P. Corvisiero, R. Menegazzo, Frank Strieder, C. Rolfs, E. Somorjai, Gy. Gyürky, B. Limata, C. Rossi Alvarez, G. Gervino, Zs. Fülöp, C. Gustavino, M. Marta, H. P. Trautvetter, Vincenzo Roca, Paolo Prati, G., Gyurky, D., Bemmerer, F., Confortola, H., Costantini, A., Formicola, R., Bonetti, C., Broggini, P., Corvisiero, Z., Eleke, Z., Fulop, G., Gervino, A., Guglielmetti, C., Gustavino, G., Imbriani, M., Junker, M., Laubenstein, A., Lemut, B., Limata, V., Lozza, M., Marta, R., Menegazzo, P., Prati, V., Roca, C., Rolf, C., ROSSI ALVAREZ, E., Somorjai, O., Straniero, F., Strieder, Terrasi, Filippo, H. P., Trautvetter, G., Gyürky, Z., Fülöp, Imbriani, Gianluca, Limata, BENEDICTA NORMANNA, Roca, Vincenzo, C., Rossi Alvarez, and F., Terrasi
Subjects: Physics, Nuclear and High Energy Physics, comparison with other data, S-factor, Theoretical models, Zero-point energy, Alpha (ethology), FOS: Physical sciences, activation measurement, nuclear reaction, Nuclear physics, Cross section (physics), Activation method, Nuclear Experiment (nucl-ex), Nuclear Experiment
Abstract: Recently, the LUNA collaboration has carried out a high precision measurement on the 3He(alpha,gamma)7Be reaction cross section with both activation and on-line gamma-detection methods at unprecedented low energies. In this paper the results obtained with the activation method are summarized. The results are compared with previous activation experiments and the zero energy extrapolated astrophysical S factor is determined using different theoretical models., Comment: Accepted for publication in Journal of Physics G
Published: 2008

246. Recoil Separator ERNA: measurement of 3He(α,γ)7Be

Author: Vincenzo Roca, D. Schürmann, R. Kunz, A. Ordine, C. Rolfs, Gianluca Imbriani, M. De Cesare, Antonio D'Onofrio, Frank Strieder, N. De Cesare, A. Di Leva, Detlef Rogalla, Lucio Gialanella, E. Somorjai, Mario R. Romano, Filippo Terrasi, A., DI LEVA, M., DE CESARE, D., Schuermann, N., DE CESARE, D'Onofrio, Antonio, Gialanella, Lucio, R., Kunz, G., Imbriani, A., Ordine, V. ROCA D., Rogalla, C., Rolf, M., Romano, E., Somorjai, F., Strieder, Terrasi, Filippo, DI LEVA, Antonino, M., De Cesare, D., Schürmann, N., De Cesare, A., D’Onofrio, L., Gialanella, Imbriani, Gianluca, Roca, Vincenzo, D., Rogalla, Romano, Mario, and F., Terrasi
Subjects: Physics, Nuclear and High Energy Physics, Physics::Instrumentation and Detectors, Electron capture, Solar neutrino, Detector, Spectral line, Nuclear physics, Recoil, Big Bang nucleosynthesis, Nuclear Astrophysics, Nuclear astrophysics, Thermal emittance, Instrumentation, Experomental Nuclear physic
Abstract: The reaction He 3 ( α , γ ) Be 7 plays a key role for the understanding of the production of 7Li in Big Bang nucleosynthesis as well as for the high energy component of the solar neutrino spectrum. The uncertainty in its absolute cross-section arises from systematic differences of the available data sets. In various experiments the cross-section was measured by the detection of the prompt γ -rays or by the off-line observation of the γ -rays following the 7Be electron capture; in a few cases both observations were carried out. We report on a new approach based on the use of the recoil separator ERNA (European Recoil separator for Nuclear Astrophysics) to detect directly the 7Be recoils as well as the prompt γ -rays in coincidence with the recoils. We present technical details of the experimental setup, such as a recirculating 3He gas target, a TOF-E end detector, and a NaI detector array. In addition, the measurement of the separator acceptance is discussed and compared to the expected recoil emittance. The feasibility of the approach is demonstrated by sample spectra, indicating cross-section determinations of He 3 ( α , γ ) Be 7 in the energy range E cm = 0.7 – 3.3 MeV with high precision and accuracy.
Published: 2008

247. Recent results and prospective of the LUNA experiment

Author: Gianluca Imbriani and Imbriani, Gianluca
Subjects: Nuclear reaction, Physics, Nuclear and High Energy Physics, CNO cycle, Stars: evolution, Abundance, Nucleosynthesis, Globular cluster, Solar neutrino, Context (language use), Astrophysics, Nucleosynthesi
Abstract: I will describe the measurement of 14N(p,γ)15O done in the context of the LUNA experiment. The determination of the astrophysical S-factor of the 14N(p,γ)15O reaction is of great interest because this reaction represents the bottleneck of the CNO cycle, which in turn has a large influence on the determination of the age of globular clusters and also plays a role in the estimation of the solar neutrino fluxes. Moreover I discuss the prospective of the LUNA experiment.
Published: 2007

248. CNO hydrogen burning studied deep underground

Author: C. Rolfs, Daniel Bemmerer, Gy. Gyürky, Carlo Broggini, C. Rossi Alvarez, R. Menegazzo, R. Bonetti, F. Schümann, H. P. Trautvetter, G. Gervino, B. Limata, Gianluca Imbriani, Oscar Straniero, Frank Strieder, Filippo Terrasi, João Cruz, A. P. Jesus, F. Confortola, M. Junker, A. Guglielmetti, Mario R. Romano, A. Formicola, Zs. Fülöp, A. Lemut, H. Costantini, Detlef Rogalla, C. Gustavino, Vincenzo Roca, Paolo Prati, E. Somorjai, P. Corvisiero, Bemmerer, D., Confortola, F., Lemut, A., Bonetti, R., Broggini, C., Corvisiero, P., Costantini, H., Cruz, J., Formicola, A., Fulop, Z. s., Gervino, G., Guglielmetti, A., Gustavino, C., Gyurky, G. y., Imbriani, Gianluca, Jesus, A. P., Junker, M., Limata, B., Menegazzo, R., Prati, P., Roca, Vincenzo, Rogalla, D., Rolfs, C., Romano, Mario, Rossi Alvarez, C., Schuemann, F., Somorjai, E., Straniero, O., Strieder, F., Terrasi, F., Trautvetter, H. P., D., Bemmerer, A., Lemut, R., Bonetti, C., Broggini, P., Corvisiero, H., Costantini, J., Cruz, A., Formicola, Z., Fulop, G., Gervino, A., Guglielmetti, C., Gustavino, G., Gyurky, G., Imbriani, A. P., Jesu, M., Junker, B., Limata, R., Menegazzo, P., Prati, V., Roca, D., Rogalla, C., Rolf, M., Romano, C., ROSSI ALVAREZ, F., Schu, Mann, E., Somorjai, O., Straniero, F., Strieder, Terrasi, Filippo, and H. P., Trautvetter
Subjects: Physics, Nuclear and High Energy Physics, CNO cycle, Hydrogen, and linear accelerators - X- and γ-ray spectroscopy, collective, Extrapolation, chemistry.chemical_element, Alpha particle, Radiative capture - Hydrostatic stellar nucleosynthesis - Electrostatic, Nuclear physics, chemistry, Excited state, Nuclear astrophysics, Nuclear fusion, Atomic physics, Ground state
Abstract: In stars, four hydrogen nuclei are converted into a helium nucleus in two competing nuclear fusion processes, namely the proton-proton chain (p-p chain) and the carbon-nitrogen-oxygen (CNO) cycle. For temperatures above 20 million kelvin, the CNO cycle dominates energy production, and its rate is determined by the slowest process, the 14N(p,γ)15O radiative capture reaction. This reaction proceeds through direct and resonant capture into the ground state and several excited states in 15O. High energy data for capture into each of these states can be extrapolated to stellar energies using an R-matrix fit. The results from several recent extrapolation studies are discussed. A new experiment at the LUNA (Laboratory for Underground Nuclear Astrophysics) 400kV accelerator in Italy's Gran Sasso laboratory measures the total cross section of the 14N(p,γ)15O reaction with a windowless gas target and a 4π BGO summing detector, down to center of mass energies as low as 70keV. After reviewing the characteristics of the LUNA facility, the main features of this experiment are discussed, as well as astrophysical scenarios where cross section data in the energy range covered have a direct impact, without any extrapolation.
Published: 2006

249. Low energy measurement of the 14N(p,γ)15O total cross section at the LUNA underground facility

Author: Bemmerer, D., Confortola, F., Lemut, A., Bonetti, R., Broggini, C., Corvisiero, P., Costantini, H., Cruz, J., Formicola, A., Fülöp, Z. s., Gervino, Gianpiero, Guglielmetti, A., Gustavino, C., Gyürky, G. y., Imbriani, G., Jesus, A., Junker, M., Limata, B., Menegazzo, R., Prati, P, Roca, V., Rolfs, C., Rogalla, D., Romano, M., Rossi Alvarez, C., Schümann, F., Somorjai, E., Straniero, O., Strieder, F., Terrasi, F., Trautvetter, H. P., D., Bemmerer, F., Confortola, A., Lemut, R., Bonetti, C., Broggini, P., Corvisiero, H., Costantini, J., Cruz, A., Formicola, Fülöp, Z. s., G., Gervino, A., Guglielmetti, C., Gustavino, Gyürky, G. y., Imbriani, Gianluca, A., Jesu, M., Junker, B., Limata, R., Menegazzo, P., Prati, Roca, Vincenzo, C., Rolf, D., Rogalla, Romano, Mario, C., Rossi Alvarez, F., Schümann, E., Somorjai, O., Straniero, F., Strieder, F., Terrasi, and H. P., Trautvetter
Subjects: Physics, Experimental Nuclear Physic, Nuclear and High Energy Physics, CNO cycle, S-factor, Underground accelerator, 14N(p, γ)15O, Direct measurement, underground laboratory, γ)15O, Nuclear physics, Cross section (physics), Low energy, 14N(p, National laboratory, Nuclear Astrophysic
Abstract: Deep underground in Gran Sasso National Laboratory (Italy), at the LUNA facility, the cross section of the 14N(p, γ)15O, the slowest process of the CNO cycle, has been measured at energies much lower than achieved before. Using a 400 kV accelerator, a windowless gas target and a 4π BGO summing detector, direct cross section data has been obtained down to 70 keV, reaching a value of 0.24 picobarn, corresponding to an S-factor of 1.74±0.14(stat)±0.14(syst) keV barn. The Gamow peak has been covered by direct experimental data for several scenarios of stable and explosive hydrogen burning. The ωγ strength of the 259 keV resonance has been re-measured obtaining 12.8±0.3(stat)±0.4(syst) meV. The stellar reaction rate has been calculated for temperatures 0.09×109−0.3×109 K. A complete description of the experiment is here presented, including the impact of the present data on nucleosynthesis in AGB stars.
Published: 2006

250. Electron Screening: A Review

Author: Antonio D'Onofrio, K. U. Kettner, E. Somorijai, L. Gang, Gianluca Imbriani, H. Luis, Marialuisa Aliotta, Filippo Terrasi, B. Burchard, João Cruz, S. Zeng, Vincenzo Roca, C. Rolfs, Carlo Broggini, F. Raiola, L. Gialanella, B. Limata, Gyuri Gyürky, Hans Werner Becker, A. Di Leva, M. Junker, Mario R. Romano, J.P. Ribeiro, A. P. Jesus, D. Schürmann, Frank Strieder, Zsolt Fülöp, M. Fonseca, F., Raiola, J., Cruz, G., Gyürky, Z., Fülöp, S., Zeng, M., Aliotta, H. W., Becker, B., Burchard, C., Broggini, DI LEVA, Antonino, A., D'Onofrio, M., Fonseca, L., Gang, L., Gialanella, Imbriani, Gianluca, A. P., Jesu, M., Junker, K. U., Kettner, B., Limata, H., Lui, J. P., Ribeiro, Roca, Vincenzo, C., Rolf, M., Romano, D., Schürmann, E., Somorijai, F., Strieder, and F., Terrasi
Subjects: symbols.namesake, Screening effect, Chemistry, Atom, symbols, Electron, Plasma, Atomic physics, Valence electron, Debye length, Debye model, Debye
Abstract: Understanding the electron screening effect in the laboratory is critical for a correct interpretation of low‐energy nuclear reactions in stars. Extensive studies of the electron screening effect in deuterated metals (54 metals) and other environments have been carried out in Bochum in the last 4 years. Experimental results of anomalous enhancements have been interpreted in terms of the Debye plasma model applied to quasi‐free metallic electrons. For the d(d,p)t reaction in metallic environments, the variation of hydrogen solubility in the samples as a function of temperature has also been measured, showing an anti‐correlation with screening enhancement as expected. Within this model, the deduced number of valence electrons per metallic atom also agrees with the corresponding number from the Hall coefficient. Recently, the expected temperature dependence of the screening potential has been verified together with the expected Zt scaling (with the metallic host) of the Debye radius. Preliminary results on the 7Li(p,α) and 6Li(p,α) reactions in Li2WO4 insulator, Li metal and PdLi alloys confirm the expected behaviour of the screening effect and further supports the applicability of the Debye model. Indeed, the proposed model also accounts for the high screening potential (Ue = 900±50 eV) observed in previous studies of the reactions 9Be(p,α) and 9Be(p,d), which was not understood at the time. A review of all these results will be presented.
Published: 2006
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