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2,165 results on '"Woods P. J"'

1. Description and outlook of the 50,53Cr(n,γ) cross section measurement at n_TOF and HiSPANoS

Author: Pérez-Maroto P., Guerrero C., Casanovas A., Fernández B., Aberle O., Alcayne V., Altieri S., Amaducci S., Andrzejewski J., Babiano-Suarez V., Bacak M., Balibrea Correa J., Beltrami C., Bennett S., Bernardes A. P., Berthoumieux E., Beyer R., Boromiza M., Bosnar D., Caamaño M., Calviño F., Calviani M., Cano-Ott D., Castelluccio D. M., Cerutti F., Cescutti G., Chasapoglou S., Chiaveri E., Colombetti P., Colonna N., Console Camprini P., Cortés G., Cortés-Giraldo M. A., Cosentino L., Cristallo S., Dellmann S., Di Castro M., Di Maria S., Diakaki M., Dietz M., Domingo-Pardo C., Dressler R., Dupont E., Durán I., Eleme Z., Fargier S., Fernández-Domínguez B., Finocchiaro P., Fiore S., Furman V., García-Infantes F., Gawlik-Ramięga A., Gervino G., Gilardoni S., González-Romero E., Gunsing F., Gustavino C., Heyse J., Hillman W., Jenkins D. G., Jericha E., Junghans A., Kadi Y., Kaperoni K., Kaur G., Kimura A., Knapová I., Kokkoris M., Kopatch Y., Krtička M., Kyritsis N., Ladarescu I., Lederer-Woods C., Lerendegui-Marco J., Lerner G., Manna A., Martínez T., Masi A., Massimi C., Mastinu P., Mastromarco M., Maugeri E. A., Mazzone A., Mendoza E., Mengoni A., Michalopoulou V., Milazzo P. M., Mucciola R., Murtas F., Musacchio-Gonzalez E., Musumarra A., Negret A., Pérez de Rada A., Patronis N., Pavón-Rodríguez J. A., Pellegriti M. G., Perkowski J., Petrone C., Pirovano E., Plaza del Olmo J., Pomp S., Porras I., Praena J., Quesada J. M., Reifarth R., Rochman D., Romanets Y., Rubbia C., Sánchez-Caballero A., Sabaté-Gilarte M., Schillebeeckx P., Schumann D., Sekhar A., Smith A. G., Sosnin N. V., Stamati M. E., Sturniolo A., Tagliente G., Tarifeño-Saldivia A., Tarrío D., Torres-Sánchez P., Vagena E., Valenta S., Variale V., Vaz P., Vecchio G., Vescovi D., Vlachoudis V., Vlastou R., Wallner A., Woods P. J., Wright T., Zarrella R., and Žugec P.
Subjects: Physics, QC1-999
Abstract: Chromium is a very relevant element regarding criticality safety in nuclear reactors because of its presence in stainless steel, an important structural material. Currently, there are serious discrepancies between the different evaluations regarding the neutron capture cross sections of 50Cr and 53Cr, most probably related to the difficulty of reducing and then estimating the very large neutron scattering effects on the shape of the resonances. In this context, there is a recent entry in the Nuclear Energy Agency (NEA) High Priority Request List (HPRL) to measure these reactions between 1 and 100 keV with an accuracy of 8-10%. In response to this request, we have performed a time-of-flight experiment at CERN n_TOF (Switzerland) and a complementary activation experimenton 50Crat30and90keVatCNAHiSPANoS(Spain).Theexperiments are presented herein, together with a discussion on the quality of the preliminary data and the results to be expected.
Published: 2024
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2. Measurement and analysis of the $^{246}$Cm and $^{248}$Cm neutron capture cross-sections at the EAR2 of the n TOF facility

Author: Alcayne, V., Kimura, A., Mendoza, E., Cano-Ott, D., Aberle, O., Álvarez-Velarde, F., Amaducci, S., Andrzejewski, J., Audouin, L., Bécares, V., Babiano-Suarez, V., Bacak, M., Barbagallo, M., Bečvář, F., Bellia, G., Berthoumieux, E., Billowes, J., Bosnar, D., Brown, A., Busso, M., Caamaño, M., Caballero-Ontanaya, L., Calviño, F., Calviani, M., Casanovas, A., Cerutti, F., Chen, Y. H., Chiaveri, E., Colonna, N., Cortés, G., Cortés-Giraldo, M. A., Cosentino, L., Cristallo, S., Damone, L. A., Diakaki, M., Dietz, M., Domingo-Pardo, C., Dressler, R., Dupont, E., Durán, I., Eleme, Z., Fernández-Domınguez, B., Ferrari, A., Finocchiaro, P., Furman, V., Göbel, K., Garg, R., Gawlik-Ramiega, A., Gilardoni, S., Glodariu, T., Gonçalves, I. F., González-Romero, E., Guerrero, C., Gunsing, F., Harada, H., Heinitz, S., Heyse, J., Jenkins, D. G., Jericha, E., Käppeler, F., Kadi, Y., Kivel, N., Kokkoris, M., Kopatch, Y., Krtička, M., Kurtulgil, D., Ladarescu, I., Lederer-Woods, C., Leeb, H., Lerendegui-Marco, J., Meo, S. Lo, Lonsdale, S. J., Macina, D., Manna, A., Martınez, T., Masi, A., Massimi, C., Mastinu, P., Mastromarco, M., Matteucci, F., Maugeri, E. A., Mazzone, A., Mengoni, A., Michalopoulou, V., Milazzo, P. M., Mingrone, F., Musumarra, A., Negret, A., Nolte, R., Ogállar, F., Oprea, A., Patronis, N., Pavlik, A., de Rada, A. Pérez, Perkowski, J., Persanti, L., Porras, I., Praena, J., Quesada, J. M., Radeck, D., Ramos-Doval, D., Rauscher, T., Reifarth, R., Rochman, D., Romanets, Y., Rubbia, C., Sabaté-Gilarte, M., Saxena, A., Schillebeeckx, P., Schumann, D., Smith, A. G., Sosnin, N. V., Stamatopoulos, A., Tagliente, G., Tain, J. L., Talip, T., Tarifeño-Saldivia, A., Tassan-Got, L., Torres-Sánchez, P., Tsinganis, A., Ulrich, J., Urlass, S., Valenta, S., Vannini, G., Variale, V., Vaz, P., Ventura, A., Vlachoudis, V., Vlastou, R., Wallner, A., Woods, P. J., Wright, T., and Žugec, P.
Subjects: Nuclear Experiment
Abstract: The $^{246}$Cm(n,$\gamma$) and $^{248}$Cm(n,$\gamma$) cross-sections have been measured at the Experimental Area 2 (EAR2) of the n_TOF facility at CERN with three C$_6$D$_6$ detectors. This measurement is part of a collective effort to improve the capture cross-section data for Minor Actinides (MAs), which are required to estimate the production and transmutation rates of these isotopes in light water reactors and innovative reactor systems. In particular, the neutron capture in $^{246}$Cm and $^{248}$Cm open the path for the formation of other Cm isotopes and heavier elements such as Bk and Cf and the knowledge of (n,$\gamma$) cross-sections of these Cm isotopes plays an important role in the transport, transmutation and storage of the spent nuclear fuel. The reactions $^{246}$Cm(n,$\gamma$) and $^{248}$Cm(n,$\gamma$) have been the two first capture measurements analyzed at n_TOF EAR2. Until this experiment and two recent measurements performed at J-PARC, there was only one set of data of the capture cross-sections of $^{246}$Cm and $^{248}$Cm, that was obtained in 1969 in an underground nuclear explosion experiment. In the measurement at n_TOF a total of 13 resonances of $^{246}$Cm between 4 and 400 eV and 5 of $^{248}$Cm between 7 and 100 eV have been identified and fitted. The radiative kernels obtained for $^{246}$Cm are compatible with JENDL-5, but some of them are not with JENDL-4, which has been adopted by JEFF-3.3 and ENDF/B-VIII.0. The radiative kernels obtained for the first three $^{248}$Cm resonances are compatible with JENDL-5, however, the other two are not compatible with any other evaluation and are 20% and 60% larger than JENDL-5.
Published: 2024

3. Observation and spectroscopy of proton-unbound nucleus $^{21}$Al

Author: Kostyleva, D., Xu, X. -D., Mukha, I., Acosta, L., Bajzek, M., Casarejos, E., Ciemny, A. A., Cortina-Gil, D., Dominik, W., Dueñas, J. A., Espino, J. M., Estradé, A., Farinon, F., Fomichev, A., Geissel, H., Gómez-Camacho, J., Gorshkov, A., Grigorenko, L. V., Janas, Z., Kamiński, G., Kiselev, O., Knöbel, R., Korsheninnikov, A. A., Krupko, S., Kuich, M., Kurz, N., Litvinov, Yu. A., Marquinez-Durán, G., Martel, I., Mazzocchi, C., Nikolskii, E. Yu., Nociforo, C., Ordúz, A. K., Pfützner, M., Pietri, S., Pomorski, M., Prochazka, A., Rodríguez-Tajes, C., Rymzhanova, S., Sánchez-Benítez, A. M., Scheidenberger, C., Simon, H., Sitar, B., Slepnev, R., Stanoiu, M., Strmen, P., Sümmerer, K., Szarka, I., Takechi, M., Tanaka, Y. K., Weick, H., Winfield, J. S., Woods, P. J., and Zhukov, M. V.
Subjects: Nuclear Experiment
Abstract: We report on the observation of previously-unknown isotope $^{21}$Al, the first unbound aluminum isotope located beyond the proton dripline. The $^{21}$Al nucleus decays by one-proton (1p) emission, and its in-flight decays were detected by tracking trajectories of all decay products with micro-strip silicon detectors. The 1p-emission processes were studied by analyses of the measured angular correlations of decay products $^{20}$Mg+p. The 1p-decay energies of ground and low-lying excited states of $^{21}$Al, its mass excess and proton separation energy value $S_p$=$-1.1(1)$ MeV were determined., Comment: 6 pages, 7 figures
Published: 2024
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4. Study of decay properties of Ba to Nd nuclei (A~160) relevant to the formation of the r-process rare-earth peak

Author: Pallàs M., Tarifeño-Saldivia A., Kiss G. G., Tain J. L., Tolosa-Delgado A., Vitéz-Sveiczer A., Calviño F., Agramunt J., Aguilera P., Algora A., Allmond J. M., Baba H., Brewer N. T., Caballero-Folch R., Coleman-Smith P. J., Cortes G., Davinson T., Dillmann I., Domingo-Pardo C., Estrade A., Fukuda N., Go S., Griffin C. J., Grzywacz R. K., Hall O., Harkness-Brennan L. J., Isobe T., Kahl D., King T. T., Korgul A., Kovács S., Kubono S., Labiche M., Liu J., Madurga M., Miernik K., Molina F., Mont-Geli N., Morales A. I., Nácher E., Navarro A., Nepal N., Nishimura S., Piersa-Silkowska M., Phong V., Rasco B. C., Romero-Barrientos J., Rubio B., Rykaczewski K. P., Saito Y., Sakurai H., Shimizu Y., Singh M., Sumikama T., Suzuki H., Szegedi T. N., Takeda H., Wang K., Wolińska-Cichocka M., Woods P. J., and Yokoyama R.
Subjects: Physics, QC1-999
Abstract: Half-lifes (T1/2) of exotic neutron-rich isotopes of Ba, La, Ce, Pr, and Nd were measured at the RIKEN Nishina Center. The experimental setup consisted of the BigRIPS in-flight separator for ion selection identification, the Advance Implantation Detector Array (AIDA) for ions and β detection, and the BRIKEN detector for neutron counting. Using this setup, 4 new T1/2 have been measured for the first time, and 38 T1/2 have been remeasured with improved precision in several cases. These new experimental data should help to constrain theoretical models for calculations of T1/2. The status of the experimental analysis and preliminary results are provided in this contribution.
Published: 2023
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5. Measurement of the 241Am(n,γ) cross section at the n_TOF facility at CERN

Author: Oprea A., Gunsing F., Schillebeeckx P., Aberle O., Bacak M., Berthoumieux E., Cano-Ott D., Diakaki M., Dupont E., Geslot B., Glodariu† T., Heyse J., Mendoza E., Negret A., Alcayne V., Amaducci S., Andrzejewski J., Audouin L., Bécares V., Babiano-Suarez V., Barbagallo M., Bečvář F., Bellia G., Billowes J., Bosnar D., Brown A., Busso M., Caamaño M., Caballero-Ontanaya L., Calviño F., Calviani M., Casanovas A., Cerutti F., Chen Y. H., Chiaveri E., Colonna N., Cortés G., Cortés-Giraldo M. A., Cosentino L., Cristallo S., Damone L. A., Dietz M., Domingo-Pardo C., Dressler R., Durán I., Eleme Z., Fernández-Domínguez B., Ferrari A., Finocchiaro P., Furman V., Göbel K., Garg R., Gawlik-Ramięga A., Gilardoni S., Gonçalves I. F., González-Romero E., Guerrero C., Harada H., Heinitz S., Jenkins D. G., Jericha E., Käppeler† F., Kaur G., Kadi Y., Kimura A., Kivel N., Kokkoris M., Kopatch Y., Krtička M., Kurtulgil D., Ladarescu I., Lederer-Woods C., Leeb H., Lerendegui-Marco J., Lo Meo S., Lonsdale S. J., Macina D., Manna A., Martínez T., Masi A., Massimi C., Mastinu P., Mastromarco M., Matteucci F., Maugeri E. A., Mazzone A., Mengoni A., Michalopoulou V., Milazzo P. M., Mingrone F., Musumarra A., Nolte R., Ogállar F., Patronis N., Pavlik A., Perkowski J., Piersanti L., Porras I., Praena J., Quesada J. M., Radeck D., Ramos-Doval D., Rauscher T., Reifarth R., Rochman D., Rubbia C., Sabaté-Gilarte M., Saxena A., Schumann D., Smith A. G., Sosnin N. V., Stamatopoulos A., Tagliente G., Tain J. L., Talip T., Tarifeño-Saldivia A., Tassan-Got L., Torres-Sánchez P., Tsinganis A., Ulrich J., Urlass S., Valenta S., Vannini G., Variale V., Vaz P., Ventura A., Vlachoudis V., Vlastou R., Wallner A., Woods P. J., Wright T., and Žugec P.
Subjects: Physics, QC1-999
Abstract: The neutron capture cross section of 241Am is an important quantity for nuclear energy production and fuel cycle scenarios. Several measurements have been performed in recent years with the aim to reduce existing uncertainties in evaluated data. Two previous measurements, performed at the 185 m flight-path station EAR1 of the neutron time-of-flight facility n_TOF at CERN, have permitted to substantially extend the resolved resonance region, but suffered in the near-thermal energy range from the unfavorable signal-to-background ratio resulting from the combination of the high radioactivity of 241Am and the rather low thermal neutron flux. The here presented 241Am(n,γ) measurement, performed with C6D6 liquid scintillator gamma detectors at the 20 m flight-path station EAR2 of the n_TOF facility, took advantage of the much higher neutron flux. The current status of the analysis of the data, focussed on the low-energy region, will be described here.
Published: 2023
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6. Results of the 244Cm, 246Cm and 248Cm neutron-induced capture cross sections measurements at EAR1 and EAR2 of the n_TOF facility

Author: Alcayne V., Mendoza E., Cano-Ott D., Kimura A., Aberle O., Amaducci S., Andrzejewski J., Audouin L., Babiano-Suarez V., Bacak M., Barbagallo M., Bécares V., Bečvář F., Bellia G., Berthoumieux E., Billowes J., Bosnar D., Brown A. S., Busso M., Caamaño M., Caballero L., Calviani M., Calviño F., Casanovas A., Cerutti F., Chen Y. H., Chiaveri E., Colonna N., Cortés G. P., Cortés-Giraldo M. A., Cosentino L., Cristallo S., Damone L. A., Diakaki M., Dietz M., Domingo-Pardo C., Dressler R., Dupont E., Durán I., Eleme Z., Fernández-Domíngez B., Ferrari A., Ferro-Gonçalves I., Finocchiaro P., Furman V., Garg R., Gawlik A., Gilardoni S., Glodariu T., Göbel K., González-Romero E., Guerrero C., Gunsing F., Heinitz S., Heyse J., Jenkins D. G., Jericha E., Kadi Y., Käppeler F., Kivel N., Kokkoris M., Kopatch Y., Krtička M., Kurtulgil D., Ladarescu I., Lederer-Woods C., Lerendegui-Marco J., Lo Meo S., Lonsdale S.-J., Macina D., Manna A., Martínez T., Masi A., Massimi C., Mastinu P. F., Mastromarco M., Matteucci F., Maugeri E., Mazzone A., Mengoni A., Michalopoulou V., Milazzo P. M., Mingrone F., Musumarra A., Negret A., Nolte R., Ogállar F., Oprea A., Patronis N., Pavlik A., Perkowski J., Piersanti L., Porras I., Praena J., Quesada J. M., Radeck D., Ramos Doval D., Reifarth R., Rochman D., Rubbia C., Sabaté-Gilarte M., Saxena A., Schillebeeckx P., Schumann D., Smith A. G., Sosnin N., Stamatopoulos A., Tagliente G., Tain J. L., Talip Z., Tarifeño-Saldivia A. E., Tassan-Got L., Torres-Sánchez P., Tsinganis A., Ulrich J., Urlass S., Valenta S., Vannini G., Variale V., Vaz P., Ventura A., Vlachoudis V., Vlastou R., Wallner A., Woods P. J., Wright T. J., and Žugec P.
Subjects: Physics, QC1-999
Abstract: Accurate neutron capture cross section data for minor actinides (MAs) are required to estimate the production and transmutation rates of MAs in light water reactors, critical fast reactors like Gen-IV systems, and other innovative reactor systems such as accelerator driven systems (ADS). In particular, 244Cm, 246Cm and 248Cm play a role in the transport, storage and transmutation of the nuclear waste of the current nuclear reactors, due to the contribution of these isotopes to the radiotoxicity, neutron emission, and decay heat in the spent nuclear fuel. Also, capture reactions in these Cm isotopes open the path for the formation of heavier elements. In this work, the results of the capture cross section measurement on 244Cm, 246Cm and 248Cm performed at the CERN n_TOF facility are presented. It is important to notice that the Cm samples used in the experiment at n_TOF have been used previously in an experiment at J-PARC, this experiment and the previous one done in the 70s with a nuclear explosion were the only previous capture experiments for these isotopes. At n_TOF, the capture cross section measurements of 244Cm, 246Cm and 248Cm were performed at the 20 m vertical flight path (EAR2) with three C6D6 total energy detectors. In addition, the cross section of 244Cm was measured at the 185 m flight path (EAR1) with a Total Absorption Calorimeter (TAC). The combination of measurements in EAR1 and EAR2 has contributed to controlling and reducing the systematic uncertainties in the results. The compatibility of the different measurements performed and the techniques to obtain the results are presented in this paper as well as the procedure to obtain the resonance parameters.
Published: 2023
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7. The Stellar 72Ge(n, γ) Cross Section for weak s-process: A First Measurement at n_TOF

Author: Dietz M., Lederer-Woods C., Tattersall A., Battino U., Gunsing F., Heinitz S., Lerendegui-Marco J., Krtička M., Reifarth R., Valenta S., Aberle O., Amaducci S., Andrzejewski J., Audouin L., Bacak M., Balibrea J., Barbagallo M., Bečvář F., Berthoumieux E., Billowes J., Bosnar D., Brown A., Caamaño M., Calviño F., Calviani M., Cano-Ott D., Cardella R., Casanovas A., Cerutti F., Chen Y. H., Chiaveri E., Colonna N., Cortés G., Cortés-Giraldo M. A., Cosentino L., Damone L. A., Diakaki M., Domingo-Pardo C., Dressler R., Dupont E., Durán I., Fernández-Domínguez B., Ferrari A., Ferreira P., Finocchiaro P., Göbel K., García A. R., Gawlik-Ramie˛ga A., Gilardoni S., Glodariu† T., Gonçalves I. F., González-Romero E., Griesmayer E., Guerrero C., Harada H., Heyse J., Jenkins D. G., Jericha E., Käppeler† F., Kadi Y., Kahl D., Kalamara A., Kavrigin P., Kimura A., Kivel N., Kokkoris M., Kurtulgil D., Leal-Cidoncha E., Leeb H., Lo Meo S., Lonsdale S. J., Macina D., Manna A., Marganiec J., Martínez T., Masi A., Massimi C., Mastinu P., Mastromarco M., Maugeri E. A., Mazzone A., Mendoza E., Mengoni A., Milazzo P. M., Mingrone F., Musumarra A., Negret A., Nolte R., Oprea A., Patronis N., Pavlik A., Perkowski J., Porras I., Praena J., Quesada J. M., Radeck D., Rauscher T., Rubbia C., Ryan J. A., Sabaté-Gilarte M., Saxena A., Schillebeeckx P., Schumann D., Smith A. G., Sosnin N. V., Stamatopoulos A., Tagliente G., Tain J. L., Tarifeño-Saldivia A., Tassan-Got L., Vannini G., Variale V., Vaz P., Ventura A., Vlachoudis V., Vlastou R., Wallner A., Warren S., Weiss C., Woods P. J., Wright T., and Žugec P.
Subjects: Physics, QC1-999
Abstract: The slow neutron capture process (s-process) is responsible for producing about half of the elemental abundances heavier than iron in the universe. Neutron capture cross sections on stable isotopes are a key nuclear physics input for s-process studies. The 72Ge(n, γ) Maxwellian-Averaged Cross Section (MACS) has an important influence on the production of isotopes between Ge and Zr in the weak s-process in massive stars and so far only theoretical estimations are available. An experiment was carried out at the neutron time-of-flight facility n_TOF at CERN to measure the 72Ge(n, γ) reaction for the first time at stellar neutron energies. The capture measurement was performed using an enriched 72GeO2 sample at a flight path length of 184 m, which provided high neutron energy resolution. The prompt gamma rays produced after neutron capture were detected with a set of liquid scintillation detectors (C6D6). The neutron capture yield is derived from the counting spectra taking into account the neutron flux and the gamma-ray detection efficiency using the Pulse Height Weighting Technique. Over 70 new neutron resonances were identified, providing an improved resolved reaction cross section to calculate experimental MACS values for the first time. The experiment, data analysis and the new MACS results will be presented including their impact on stellar nucleosynthesis, which was investigated using the post-processing nucleosynthesis code mppnp for a 25 solar mass model.
Published: 2023
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8. New perspectives for neutron capture measurements in the upgraded CERN-n_TOF Facility

Author: Lerendegui-Marco J., Casanovas A., Alcayne V., Aberle O., Altieri S., Amaducci S., Andrzejewski J., Babiano-Suarez V., Bacak M., Balibrea J., Beltrami C., Bennett S., Bernardes A. P., Berthoumieux E., Boromiza M., Bosnar D., Caamaño M., Calviño F., Calviani M., Cano-Ott D., Cerutti F., Cescutti G., Chasapoglou S., Chiaveri E., Colombetti P., Colonna N., Console Camprini P., Cortés G., Cortés-Giraldo M. A., Cosentino L., Cristallo S., Dellmann S., Di Castro M., Di Maria S., Diakaki M., Dietz M., Domingo-Pardo C., Dressler R., Dupont E., Durán I., Eleme Z., Fargier S., Fernández B., Fernández-Domínguez B., Finocchiaro P., Fiore S., Furman V., García-Infantes F., Gawlik-Ramiega A., Gervino G., Gilardoni S., González-Romero E., Guerrero C., Gunsing F., Gustavino C., Heyse J., Hillman W., Jenkins D. G., Jericha E., Junghans A., Kadi Y., Kaperoni K., Kaur G., Kimura A., Knapová I., Kokkoris M., Kopatch Y., Krtička M., Kyritsis N., Ladarescu I., Lederer-Woods C., Lerner G., Manna A., Martínez T., Masi A., Massimi C., Mastinu P., Mastromarco M., Maugeri E. A., Mazzone A., Mendoza E., Mengoni A., Michalopoulou V., Milazzo P. M., Mucciola R., Murtas† F., Musacchio-Gonzalez E., Musumarra A., Negret A., Pérez de Rada A., Pérez-Maroto P., Patronis N., Pavón-Rodríguez J. A., Pellegriti M. G., Perkowski J., Petrone C., Pirovano E., Plaza J., Pomp S., Porras I., Praena J., Quesada J. M., Reifarth R., Rochman D., Romanets Y., Rubbia C., Sánchez A., Sabaté-Gilarte M., Schillebeeckx P., Schumann D., Sekhar A., Smith A. G., Sosnin N. V., Stamati M. E., Sturniolo A., Tagliente G., Tarrío D., Torres-Sánchez P., Urlass S., Vagena E., Valenta S., Variale V., Vaz P., Vecchio G., Vescovi D., Vlachoudis V., Vlastou R., Wallner T., Woods P. J., Wright T., Zarrella R., and Žugec P.
Subjects: Physics, QC1-999
Abstract: The n_TOF facility has just undergone in 2021 a major upgrade with the installation of its third generation spallation target that has been designed to optimize the performance of the two n_TOF time-of-flight lines. This contribution describes the key features and limitations for capture measurements in the two beam lines prior to the target upgrade and presents first results of (n,γ) measurements carried out as part of the commissioning of the upgraded facility. In particular, the energy resolution, a key factor for both increasing the signal-to-background ratio and obtaining accurate resonance parameters, has been clearly improved for the 20 m long vertical beam-line with the new target design while keeping the remarkably high resolution of the long beamline n_TOF-EAR1. The improvements in the n_TOF neutron beam-lines need to be accompanied by improvements in the instrumentation. A review is given on recent detector R&D projects aimed at tackling the existing challenges and further improving the capabilities of this facility.
Published: 2023
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9. Compton imaging for enhanced sensitivity (n,γ) cross section TOF experiments: Status and prospects

Author: Domingo-Pardo C., Babiano-Suarez V., Balibrea-Correa J., Caballero L., Ladarescu I., Lerendegui-Marco J., Tarifeño-Saldivia A., Aberle O., Alcayne V., Altieri S., Amaducci S., Andrzejewski J., Bacak M., Beltrami C., Bennett S., Bernardes A. P., Berthoumieux E., Beyer R., Boromiza M., Bosnar D., Caamaño M., Calviño F., Calviani M., Cano-Ott D., Casanovas A., Cerutti F., Cescutti G., Chiaveri E., Colombetti P., Colonna N., Console Camprini P., Cortés G., Cortés-Giraldo M. A., Cosentino L., Cristallo S., Dellmann S., Di Castro M., Di Maria S., Diakaki M., Dietz M., Dressler R., Dupont E., Durán I., Eleme Z., Fargier S., Fernández B., Fernández-Domínguez B., Finocchiaro P., Fiore S., García-Infantes F., Gawlik-Ramie˛ga A., Gervino G., Gilardoni S., González-Romero E., Guerrero C., Gunsing F., Gustavino C., Heyse J., Hillman W., Jenkins D. G., Jericha E., Junghans A., Kadi Y., Kaperoni K., Kaur G., Kimura A., Knapová I., Kokkoris M., Köster U., Krtička M., Kyritsis N., Lederer-Woods C., Lerner G., Manna A., Martínez T., Masi A., Massimi C., Mastinu P., Mastromarco M., Maugeri E. A., Mazzone A., Mendoza E., Mengoni A., Michalopoulou V., Milazzo P. M., Mucciola R., Murtas† F., Musacchio-Gonzalez E., Musumarra A., Negret A., Pérez de Rada A., Pérez-Maroto P., Patronis N., Pavón-Rodríguez J. A., Pellegriti M. G., Perkowski J., Petrone C., Pirovano E., Plaza J., Pomp S., Porras I., Praena J., Quesada J. M., Reifarth R., Rochman D., Romanets Y., Rubbia C., Sánchez-Caballero A., Sabaté-Gilarte M., Schillebeeckx P., Schumann D., Sekhar A., Smith A. G., Sosnin N. V., Stamati M. E., Sturniolo A., Tagliente G., Tarrío D., Torres-Sánchez P., Vagena E., Valenta S., Variale V., Vaz P., Vecchio G., Vescovi D., Vlachoudis V., Vlastou R., Wallner A., Woods P. J., Wright T., Zarrella R., and Žugec P.
Subjects: Physics, QC1-999
Abstract: Radiative neutron-capture cross sections are of pivotal importance in many fields such as nucle-osynthesis studies or innovative reactor technologies. A large number of isotopes have been measured with high accuracy, but there are still a large number of relevant isotopes whose cross sections could not be experimentally determined yet, at least with sufficient accuracy and completeness, owing to limitations in detection techniques, sample production methods or in the facilities themselves. In the context of the HYMNS (High-sensitivitY Measurements of key stellar Nucleo-Synthesis reactions) project over the last six years we have developed a novel detection technique aimed at background suppression in radiative neutron-capture time-of-flight measurements. This new technique utilizes a complex detection set-up based on position-sensitive radiation-detectors deployed in a Compton-camera array configuration. The latter enables to implement gamma-ray imaging techniques, which help to disentangle true capture events arising from the sample under study and contaminant background events from the surroundings. A summary on the main developments is given in this contribution together with an update on recent experiments at CERN n_TOF and an outlook on future steps.
Published: 2023
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10. High resolution 80Se(n,γ) cross section measurement at CERN n_TOF

Author: Babiano-Suarez V., Balibrea-Correa J., Caballero-Ontanaya L., Domingo-Pardo C., Ladarescu I., Lerendegui-Marco J., Tain J. L., Calviño F., Casanovas A., Tarifeño-Saldivia A., Guerrero C., Aberle O., Alcayne V., Amaducci S., Andrzejewski J., Audouin L., Bacak M., Barbagallo M., Bennett S., Berthoumieux E., Billowes J., Bosnar D., Brown A., Busso M., Caamaño M., Calviani M., Cano-Ott D., Cerutti F., Chiaveri E., Colonna N., Cortés G., Cortés-Giraldo M. A., Cosentino L., Cristallo S., Damone L. A., Davies P. J., Diakaki M., Dietz M., Dressler R., Ducasse Q., Dupont E., Durán I., Eleme Z., Fernández-Domínguez B., Ferrari A., Finocchiaro P., Furman V., Göbel K., Garg R., Gawlik-Ramięga A., Gilardoni S., Gonçalves I. F., González-Romero E., Gunsing F., Harada H., Heinitz S., Heyse J., Jenkins D. G., Junghans A., Käppeler F., Kadi Y., Kimura A., Knapová I., Kokkoris M., Kopatch Y., Krtička M., Kurtulgil D., Lederer-Woods C., Leeb H., Lonsdale S. J., Macina D., Manna A., Martínez T., Masi A., Massimi C., Mastinu P., Mastromarco M., Maugeri E. A., Mazzone A., Mendoza E., Mengoni A., Michalopoulou V., Milazzo P. M., Mingrone F., Moreno-Soto J., Musumarra A., Negret A., Nolte R., Ogállar F., Oprea A., Patronis N., Pavlik A., Perkowski J., Persanti L., Petrone C., Pirovano E., Porras I., Praena J., Quesada J. M., Ramos-Doval D., Rauscher T., Reifarth R., Rochman D., Romanets Y., Rubbia C., Sabaté-Gilarte M., Saxena A., Schillebeeckx P., Schumann D., Sekhar A., Smith A. G., Sosnin N. V., Sprung P., Stamatopoulos A., Tagliente G., Tassan-Got L., Thomas Th., Torres-Sánchez P., 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., and Žugec P.
Subjects: Physics, QC1-999
Abstract: Neutron capture cross section measurements of isotopes close to s-process branching-points are of fundamental importance for the understanding of this nucleosynthesis mechanism through which about 50% of the elements heavier than iron are produced. We present in this contribution the results corresponding to the high resolution measurement, for first time ever, of the 80Se(n, γ) cross section, in which 98 resonances never measured before have been reported. As a consequence, ten times more precise values for the MACS have been obtained compared to previous accepted value adopted in the astrophysical KADoNiS data base.
Published: 2023
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11. Neutron capture and total cross-section measurements on 94,95,96Mo at n_TOF and GELINA

Author: Mucciola R., Paradela C., Manna A., Alaerts G., Massimi C., Kopecky S., Mengoni A., Moens A., Schillebeeckx P., Wynants R., Aberle O., Alcayne V., Altieri S., Amaducci S., Amar Es-Sghir H., Andrzejewski J., Babiano-Suarez V., Bacak M., Balibrea J., Bennett S., Bernardes A. P., Berthoumieux E., Bosnar D., Busso M., Caamaño M., Calviño F., Calviani M., Cano-Ott D., Casanovas A., Castelluccio D. M., Cerutti F., Cescutti G., Chasapoglou S., Chiaveri E., Colombetti P., Colonna N., Console Camprini P. C., Cortés G., Cortés-Giraldo M. A., Cosentino L., Cristallo S., Di Castro M., Diacono D., Diakaki M., Dietz M., Domingo-Pardo C., Dressler R., Dupont E., Durán I., Eleme Z., Fargier S., Fernández-Domínguez B., Finocchiaro P., Fiore S., Furman V., García-Infantes F., Gawlik-Ramięga A., Gervino G., Gilardoni S., González-Romero E., Guerrero C., Gunsing F., Gustavino C., Heyse J., Jenkins D. G., Jericha E., Junghans A., Kadi Y., Katabuchi T., Knapová I., Kokkoris M., Kopatch Y., Krtička M., Kurtulgil D., Ladarescu I., Lederer-Woods C., Lerendegui-Marco J., Lerner G., Martínez T., Masi A., Mastinu P., Mastromarco M., Matteucci F., Maugeri E. A., Mazzone A., Mendoza E., Michalopoulou V., Milazzo P. M., Murtas† F., Musacchio-Gonzalez E., Musumarra A., Negret A., Oprea A., Pérez-Maroto P., Patronis N., Pavón-Rodríguez J. A., Pellegriti M. G., Perkowski J., Petrone C., Piersanti L., Pirovano E., Pomp S., Porras I., Praena J., Protti N., Quesada J. M., Rauscher T., Reifarth R., Rochman D., Romanets Y., Romano F., Rubbia C., Sánchez A., Sabaté-Gilarte M., Schumann D., Sekhar A., Smith A. G., Sosnin N. V., Spelta M., Stamati M. E., Tagliente G., Tarifeño-Saldivia A., Tarrío D., Terranova N., Torres-Sánchez P., Urlass S., Valenta S., Variale V., Vaz P., Vescovi D., Vlachoudis V., Vlastou R., Wallner A., Woods P. J., Wright T., and Žugec P.
Subjects: Physics, QC1-999
Abstract: Capture and total cross section measurements for 94,95,96Mo have been performed at the neutron time-of-flight facilities, n_TOF at CERN and GELINA at JRC-Geel. The measurements were performed using isotopically enriched samples with an enrichment above 95% for each of the 94,95,96Mo isotopes. The capture measurements were performed at n_TOF using C6D6 detectors and a new sTED detector. The transmission measurements were performed at a 10 m station of GELINA using a 6Li glass neutron detector. Preliminary results of these measurements are presented.
Published: 2023
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12. A segmented total energy detector (sTED) for (n, γ) cross section measurements at n_TOF EAR2

Author: Alcayne V., Cano-Ott D., Garcia J., González-Romero E., Martínez T., Mendoza E., Sánchez A., Plaza J., Balibrea-Correa J., Casanovas A., Domingo-Pardo C., Lerendegui-Marco J., Aberle O., Altieri S., Amaducci S., Amar Es-Sghir H., Andrzejewski J., Babiano-Suarez V., Bacak M., Balibrea J., Bennett S., Bernardes A. P., Berthoumieux E., Bosnar D., Busso M., Caamaño M., Calviño F., Calviani M., Castelluccio D. M., Cerutti F., Cescutti G., Chasapoglou S., Chiaveri E., Colombetti P., Colonna N., Console Camprini P. C., Cortés G., Cortés-Giraldo M. A., Cosentino L., Cristallo S., Di Castro M., Diacono D., Diakaki M., Dietz M., Dressler R., Dupont E., Durán I., Eleme Z., Fargier S., Fernández-Domínguez B., Finocchiaro P., Fiore S., Furman V., García-Infantes F., Gawlik-Ramięga A., Gervino G., Gilardoni S., Guerrero C., Gunsing F., Gustavino C., Heyse J., Jenkins D. G., Jericha E., Junghans A., Kadi Y., Katabuchi T., Knapová I., Kokkoris M., Kopatch Y., Krtička M., Kurtulgil D., Ladarescu I., Lederer-Woods C., Lerner G., Manna A., Masi A., Massimi C., Mastinu P., Mastromarco M., Matteucci F., Maugeri E. A., Mazzone A., Mengoni A., Michalopoulou V., Milazzo P. M., Mucciola R., Murtas† F., Musacchio-Gonzalez E., Musumarra A., Negret A., Oprea A., Pérez-Maroto P., Patronis N., Pavón-Rodríguez J. A., Pellegriti M. G., Perkowski J., Petrone C., Piersanti L., Pirovano E., Pomp S., Porras I., Praena J., Protti N., Quesada J. M., Rauscher T., Reifarth R., Rochman D., Romanets Y., Romano F., Rubbia C., Sabaté-Gilarte M., Schillebeeckx P., Schumann D., Sekhar A., Smith A. G., Sosnin N. V., Spelta M., Stamati M. E., Tagliente G., Tarifeño-Saldivia A., Tarrío D., Terranova N., Torres-Sánchez P., Urlass S., Valenta S., Variale V., Vaz P., Vescovi D., Vlachoudis V., Vlastou R., Wallner A., Woods P. J., Wright T., and Žugec P.
Subjects: Physics, QC1-999
Abstract: The neutron time-of-flight facility n_TOF is characterised by its high instantaneous neutron intensity, high-resolution and broad neutron energy spectra, specially conceived for neutron-induced reaction cross section measurements. Two Time-Of-Flight (TOF) experimental areas are available at the facility: experimental area 1 (EAR1), located at the end of the 185 m horizontal flight path from the spallation target, and experimental area 2 (EAR2), placed at 20 m from the target in the vertical direction. The neutron fluence in EAR2 is ˜ 300 times more intense than in EAR1 in the relevant time-of-flight window. EAR2 was designed to carry out challenging cross-section measurements with low mass samples (approximately 1 mg), reactions with small cross-sections or/and highly radioactive samples. The high instantaneous fluence of EAR2 results in high counting rates that challenge the existing capture systems. Therefore, the sTED detector has been designed to mitigate these effects. In 2021, a dedicated campaign was done validating the performance of the detector up to at least 300 keV neutron energy. After this campaign, the detector has been used to perform various capture cross section measurements at n_TOF EAR2.
Published: 2023
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13. The n_TOF NEAR Station Commissioning and first physics case

Author: Stamati M. E., Torres-Sánchez P., Pérez-Maroto P., Cecchetto M., Goula S., Mastromarco M., Chasapoglou S., Beltrami C., Chiesa D., Manna A., Mucciola R., Patronis N., Praena J., Guerrero C., Colonna N., Mengoni A., Massimi C., Aberle O., Alcayne V., Altieri S., Amaducci S., Amar Es-Sghir H., Andrzejewski J., Babiano-Suarez V., Bacak M., Balibrea J., Bennett S., Bernardes A. P., Berthoumieux E., Bosnar D., Busso M., Caamaño M., Calviño F., Calviani M., Cano-Ott D., Casanovas A., Castelluccio D. M., Cerutti F., Cescutti G., Chiaveri E., Colombetti P., Console Camprini P. C., Cortés G., Cortés-Giraldo M. A., Cosentino L., Cristallo S., Di Castro M., Diacono D., Diakaki M., Dietz M., Domingo-Pardo C., Dressler R., Dupont E., Durán I., Eleme Z., Fargier S., Fernández-Domínguez B., Finocchiaro P., Fiore S., Furman V., García-Infantes F., Gawlik-Ramięga A., Gervino G., Gilardoni S., González-Romero E., Gunsing F., Gustavino C., Heyse J., Jenkins D. G., Jericha E., Junghans A., Kadi Y., Katabuchi T., Knapová I., Kokkoris M., Kopatch Y., Krticka M., Kurtulgil D., Ladarescu I., Lederer-Woods C., Lerendegui-Marco J., Lerner G., Martínez T., Masi A., Mastinu P., Matteucci F., Maugeri E. A., Mazzone A., Mendoza E., Michalopoulou V., Milazzo P. M., Murtas F., Musacchio-Gonzalez E., Musumarra A., Negret A., Oprea A., Pavón-Rodríguez J. A., Pellegriti M. G., Perkowski J., Petrone C., Piersanti L., Pirovano E., Pomp S., Porras I., Protti N., Quesada J. M., Rauscher T., Reifarth R., Rochman D., Romanets Y., Romano F., Rubbia C., Sánchez A., Sabaté-Gilarte M., Schillebeeckx P., Schumann D., Sekhar A., Smith A. G., Sosnin N. V., Spelta M., Tagliente G., Tarifeño-Saldivia A., Taríro D., Terranova N., Urlass S., Valenta S., Variale V., Vaz P., Vescovi D., Vlachoudis V., Vlastou R., Wallner A., Woods P. J., Wright T., and Žugec P.
Subjects: Physics, QC1-999
Abstract: The NEAR Station is a new experimental area developed at the n_TOF Facility at CERN. The activation station of NEAR underwent a characterization of the beam following the installation of the new n_TOF Spallation Target. The commissioning of the neutron beam comprises a set of simulations made with the FLUKA code and experimental verification. The experimental determination of the neutron spectrum was made using activation techniques with three separate set-ups. Two set-ups were based on the Multi-foil Activation technique (MAM-1 and MAM-2), and the third set-up relied on the process of neutron moderation and activation of a single material (ANTILoPE). The three set-ups are presented. Also the present plans and future perspectives of the activation station of NEAR are discussed.
Published: 2023
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14. Characterisation of the n_TOF 20 m beam line at CERN with the new spallation target

Author: Pavón-Rodríguez J. A., Alcayne V., Amaducci S., Bacak M., Casanovas A., Cortés-Giraldo M. A., García-Infantes F., Lerendegui-Marco J., Manna A., Musacchio-Gonzalez E., Patronis N., Sabaté-Gilarte M., Stamati M. E., Tassan-Got L., Vlachoudis V., Aberle O., Altieri S., Amar Es-Sghir H., Andrzejewski J., Babiano-Suarez V., Balibrea J., Bennett S., Bernardes A. P., Berthoumieux E., Bosnar D., Busso M., Caamaño M., Alviño F., Calviani M., Cano-Ott D., Castelluccio D. M., Cerutti F., Cescutti G., Chasapoglou S., Chiaveri E., Colombetti P., Colonna N., Console Camprini P. C., Cortés G., Cosentino L., Cristallo S., Di Castro M., Diacono D., Diakaki M., Dietz M., Domingo-Pardo C., Dressler R., Dupont E., Durán I., Eleme Z., Fargier S., Fernández-Domínguez B., Finocchiaro P., Fiore S., Furman V., Gawlik-Ramięga A., Gervino G., Gilardoni S., González-Romero E., Guerrero C., Gunsing F., Gustavino C., Heyse J., Jenkins D. G., Jericha E., Junghans A., Kadi Y., Katabuchi T., Knapová I., Kokkoris M., Kopatch Y., Krtička M., Kurtulgil D., Ladarescu I., Lederer-Woods C., Lerner G., Martínez T., Masi A., Massimi C., Mastinu P., Mastromarco M., Matteucci F., Maugeri E. A., Mazzone A., Mendoza E., Mengoni A., Michalopoulou V., Milazzo P. M., Mucciola R., Murtas† F., Musumarra A., Negret A., Oprea A., Pérez-Maroto P., Pellegriti M. G., Perkowski J., Petrone C., Piersanti L., Pirovano E., Pomp S., Porras I., Praena J., Protti N., Quesada J. M., Rauscher T., Reifarth R., Rochman D., Romanets Y., Romano F., Rubbia C., Sánchez A., Schillebeeckx P., Schumann D., Sekhar A., Smith A. G., Sosnin N. V., Spelta M., Tagliente G., Tarifeño-Saldivia A., Tarrío D., Terranova N., Torres-Sánchez P., Urlass S., Valenta S., Variale V., Vaz P., Vescovi D., Vlastou R., Wallner A., Woods P. J., Wright T., and Žugec P.
Subjects: Physics, QC1-999
Abstract: The n_TOF facility hosts CERN’s pulsed neutron source, comprising two beam lines of different flight paths and one activation station. It is based on a proton beam delivered by the PS accelerator impinging on a lead spallation target. During Long Shutdown 2 (LS2) at CERN (2019-2021), a major upgrade of the spallation target was carried out in order to optimize the performances of the neutron beam. Therefore, the characteristics of n_TOF two experimental areas were investigated in detail. In this work, the focus is on the second experimental area (EAR2), located 20 m above the spallation target. Preliminary results of the neutron energy distribution and beam line energy resolution are presented, compared to previous experimental campaigns and Monte Carlo simulations with the FLUKA code. Moreover, preliminary results of the spatial beam profile measurements are shown.
Published: 2023
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15. First high resolution measurement of neutron capture resonances in 176Yb at the n_TOF CERN facility

Author: García-Infantes F., Praena J., Casanovas A., Mastromarco M., Aberle O., Alcayne V., Altieri S., Amaducci S., Amar Es-Sghir H., Andrzejewski J., Babiano-Suarez V., Bacak M., Balibrea J., Bennett S., Bernardes A.P., Berthoumieux E., Bosnar D., Busso M., Caamaño M., Calviño F., Calviani M., Cano-Ott D., Castelluccio D.M., Cerutti F., Cescutti G., Chasapoglou S., Chiaveri E., Colombetti P., Colonna N., Console Camprini P.C., Coréts G., Cortés-Giraldo M.A., Cosentino L., Cristallo S., Di Castro M., Diacono D., Diakaki M., Dietz M., Domingo-Pardo C., Dressler R., Dupont E., Duarn I., Eleme Z., Fargier S., Fernández-Domínguez B., Finocchiaro P., Fiore S., Furman V., Gawlik-Ramięga A., Gervino G., Gilardoni S., González-Romero E., Guerrero C., Gunsing F., Gustavino C., Heyse J., Jenkins D.G., Jericha E., Junghans A., Kadi Y., Katabuchi T., Knapova I., Kokkoris M., Kopatch Y., Krtička M., Kurtulgil D., Ladarescu I., Lederer-Woods C., Lerendegui-Marco J., Lerner G., Manna A., Martínez T., Masi A., Massimi C., Mastinu P., Atteucci F., Maugeri E. A., Mazzone A., Mendoza E., Mengoni A., Michalopoulou V., Milazzo P. M., Mucciola R., Murtas F., Musacchio-Gonzalez E., Musumarra A., Negret A., Oprea A., Pérez-Maroto P., Patronis N., Pavón-Rodríguez J. A., Pellegriti M. G., Perkowski J., Petrone C., Piersanti L., Pirovano E., Pomp S., Porras I., Protti N., Quesada J. M., Rauscher T., Reifarth R., Ochman D., Romanets Y., Romano F., Rubbia C., Sánchez A., Sabaté-Gilarte M., Schillebeeckx P., Schumann D., Sekhar A., Smith A. G., Sosnin N. V., Spelta M., Stamati M. E., Tagliente G., Tarifeño-Saldivia A., Tarrío D., Terranova N., Torres-Sánchez P., Urlass S., Valenta S., Variale V., Vaz P., Vescovi D., Vlachoudis V., Lastou R., Wallner A., Woods P. J., Wright T., and Žugec P.
Subjects: Physics, QC1-999
Abstract: Several international agencies recommend the study of new routes and new facilities for producing radioisotopes with application to nuclear medicine. 177Lu is a versatile radioisotope used for therapy and diagnosis (theranostics) of cancer with good success in neuroendocrine tumours that is being studied to be applied to a wider range of tumours. 177Lu is produced in few nuclear reactors mainly by the neutron capture on 176Lu. However, it could be produced at high-intensity celeratorbased neutron facilities. The energy of the neutrons in accelerator-based neutron facilities is higher than in thermal reactors.Thus, experimental data on the 176Yb(n,γ) cross-section in the eV and keV region are mandatory to calculate accurately the production of 177Yb, which beta decays to 177Lu. At present, there are not experimental data available from thermal to 3 keV of the 176Yb(n,γ) cross-section. In addition, there is no data in the resolved resonance region (RRR). This contribution shows the first results of the 176Yb capture measurement performed at the n_TOF facility at CERN.
Published: 2023
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16. First measurement of the 94Nb(n,γ) cross section at the CERN n_TOF facility

Author: Balibrea-Correa J., Babiano-Suárez V., Lerendegui-Marco J., Domingo-Pardo C., Ladarescu I., Tarifeño-Saldivia A., Alcayne V., Cano-Ott D., González-Romero E., Martínez T., Mendoza E., Guerrero C., Calviño F., Casanovas A., Köster U., Chiera N. M., Dressler R., Maugeri E. A., Schumann D., Aberle O., Altieri S., Amaducci S., Andrzejewski J., Bacak M., Beltrami C., Bennett S., Bernardes A. P., Berthoumieux E., Beyer R., Boromiza M., Bosnar D., Caamaño M., Calviani M., Cerutti F., Cescutti G., Chiaveri E., Colombetti P., Colonna N., Console Camprini P., Cortés G., Cortés-Giraldo M. A., Cosentino L., Cristallo S., Dellmann S., Di Castro M., Di Maria S., Diakaki M., Dietz M., Dupont E., Durán I., Eleme Z., Fargier S., Fernández B., Fernández-Domínguez B., Finocchiaro P., Fiore S., García-Infantes F., Gawlik-Ramięga A., Gervino G., Gilardoni S., Gunsing F., Gustavino C., Heyse J., Hillman W., Jenkins D. G., Jericha E., Junghans A., Kadi Y., Kaperoni K., Kaur G., Kimura A., Knapová I., Kokkoris M., Krtička M., Kyritsis N., Lederer-Woods C., Lerner G., Manna A., Masi A., Massimi C., Mastinu P., Mastromarco M., Mazzone A., Mengoni A., Michalopoulou V., Milazzo P. M., Mucciola R., Murtas F., Musacchio-Gonzalez E., Musumarra A., Negret A., Pérez de Rada A., Pérez-Maroto P., Patronis N., Pavón-Rodríguez J. A., Pellegriti M. G., Perkowski J., Petrone C., Pirovano E., Plaza J., Pomp S., Porras I., Praena J., Quesada J. M., Reifarth R., Rochman D., Romanets Y., Rubbia C., Sánchez-Caballero A., Sabaté-Gilarte M., Schillebeeckx P., Sekhar A., Smith A. G., Sosnin N. V., Stamati M. E., Sturniolo A., Tagliente G., Tarrío D., Torres-Sánchez P., Vagena E., Valenta S., Variale V., Vaz P., Vecchio G., Vescovi D., Vlachoudis V., Vlastou R., Wallner A., Woods P. J., Wright T., Zarrella R., and Žugec P.
Subjects: Physics, QC1-999
Abstract: One of the crucial ingredients for the improvement of stellar models is the accurate knowledge of neutron capture cross-sections for the different isotopes involved in the s-,r- and i- processes. These measurements can shed light on existing discrepancies between observed and predicted isotopic abundances and help to constrain the physical conditions where these reactions take place along different stages of stellar evolution. In the particular case of the radioactive 94Nb, the 94Nb(n,γ) cross-section could play a role in the determination of the s-process production of 94Mo in AGB stars, which presently cannot be reproduced by state-of-the-art stellar models. There are no previous 94Nb(n,γ) experimental data for the resolved and unresolved resonance regions mainly due to the difficulties in producing highquality samples and also due to limitations in conventional detection systems commonly used in time-of-flight experiments. Motivated by this situation, a first measurement of the 94Nb(n,γ) reaction was carried out at CERN n_TOF, thereby exploiting the high luminosity of the EAR2 area in combination with a new detection system of small-volume C6D6-detectors and a high quality 94Nb-sample. The latter was based on hyper-pure 93Nb material activated at the high-flux reactor of ILL-Grenoble. An innovative ring-configuration detection system in close geometry around the capture sample allowed us to significantly enhance the signal-to-background ratio. This set-up was supplemented with two conventional C6D6-detectors and a highresolution LaCl3(Ce)-detector, which will be employed for addressing reliably systematic effects and uncertainties. At the current status of the data analysis, 18 resonance in 94Nb+n have been observed for the first time in the neutron energy range from thermal up to 10 keV.
Published: 2023
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17. Neutron-induced cross section measurements

Author: Massimi C., Aberle O., Alcayne V., Altieri S., Amaducci S., Andrzejewski J., Babiano-Suarez V., Bacak M., Balibrea J., Beltrami C., Bennett S., Bernardes A. P., Berthoumieux E., Boromiza M., Bosnar D., Caamaño M., Calviño F., Calviani M., Cano-Ott D., Casanovas A., Castelluccio D. M., Cerutti F., Cescutti G., Chasapoglou S., Chiaveri E., Colombetti P., Colonna N., Console Camprini P., Cortés G., Cortés-Giraldo M. A., Cosentino L., Cristallo S., Dellmann S., Di Castro M., Di Maria S., Diakaki M., Dietz M., Domingo-Pardo C., Dressler R., Dupont E., Durán I., Eleme Z., Fargier S., Fernández B., Fernández-Domínguez B., Finocchiaro P., Fiore S., Furman V., GarcíaInfantes F., Gawlik-Ramięga A., Gervino G., Gilardoni S., González-Romero E., Guerrero C., Gunsing F., Gustavino C., Heyse J., Hillman W., Jenkins D. G., Jericha E., Junghans A., Kadi Y., Kaperoni K., Kaur G., Kimura A., Knapová I., Kokkoris M., Kopatch Y., Krtička M., Kyritsis N., Ladarescu I., Lederer-Woods C., Lerendegui-Marco J., Lerner G., Manna A., Martínez T., Masi A., Mastinu P., Mastromarco M., Maugeri E. A., Mazzone A., Mendoza E., Mengoni A., Michalopoulou V., Milazzo P. M., Mucciola R., Murtas F., Musacchio-Gonzalez E., Musumarra A., Negret A., Pérez de Rada A., Pérez-Maroto P., Patronis N., Pavón-Rodríguez J. A., Pellegriti M. G., Perkowski J., Petrone C., Pirovano E., Plaza J., Pomp S., Porras I., Praena J., Quesada J. M., Reifarth R., Rochman D., Romanets Y., Rubbia C., Sánchez A., Sabaté-Gilarte M., Schillebeeckx P., Schumann D., Sekhar A., Smith A. G., Sosnin N. V., Stamati M. E., Sturniolo A., Tagliente G., Tarrío D., Torres-Sánchez P., Urlass S., Vagena E., Valenta S., Variale V., Vaz P., Vecchio G., Vescovi D., Vlachoudis V., Vlastou R., Wallner A., Woods P. J., Wright T., Zarrella R., and Žugec P.
Subjects: Physics, QC1-999
Abstract: Neutron-induced cross sections represent the main nuclear input to models of stellar and Big-Bang nucleosynthesis. While (n,γ) reactions are relevant for the formation of elements heavier than iron, (n,p) and (n,α) reactions can play an important role in specific cases. The time-of-flight method is routinely used at n_TOF to experimentally determine the cross section data. In addition, recent upgrades of the facility will allow the use of activation techniques as well, possibly opening the way to a systematic study of neutron interaction with radioactive isotopes. In the last 20 years n_TOF has provided a large amount of experimental data for Nuclear Astrophysics. Our plan is to carry on challenging measurements and produce nuclear data in the next decades as well.
Published: 2023
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18. New detection systems for an enhanced sensitivity in key stellar (n,γ) measurements

Author: Lerendegui-Marco J., Babiano-Suárez V., Balibrea-Correa J., Domingo-Pardo C., Ladarescu I., Tarifeño-Saldivia A., Alcayne V., Cano-Ott D., González-Romero E., Martínez T., Mendoza E., Guerrero C., Calviño F., Casanovas A., Köster U., Chiera N. M., Dressler R., Maugeri E. A., Schumann D., Aberle O., Altieri S., Amaducci S., Andrzejewski J., Bacak M., Beltrami C., Bennett S., Bernardes A. P., Berthoumieux E., Beyer R., Boromiza M., Bosnar D., Caamaño M., Calviani M., Cerutti F., Cescutti G., Chiaveri E., Colombetti P., Colonna N., Console Camprini P., Cortés G., Cortés-Giraldo M. A., Cosentino L., Cristallo S., Dellmann S., Di Castro M., Di Maria S., Diakaki M., Dietz M., Dupont E., Durán I., Eleme Z., Fargier S., Fernández B., Fernández-Domínguez B., Finocchiaro P., Fiore S., García-Infantes F., Gawlik-Ramięga A., Gervino G., Gilardoni S., Gunsing F., Gustavino C., Heyse J., Hillman W., Jenkins D. G., Jericha E., Junghans A., Kadi Y., Kaperoni K., Kaur G., Kimura A., Knapová I., Kokkoris M., Krtička M., Kyritsis N., Lederer-Woods C., Lerner G., Manna A., Masi A., Massimi C., Mastinu P., Mastromarco M., Mazzone A., Mengoni A., Michalopoulou V., Milazzo P. M., Mucciola R., Murtas F., Musacchio-Gonzalez E., Musumarra A., Negret A., Pérez de Rada A., Pérez-Maroto P., Patronis N., Pavón-Rodríguez J. A., Pellegriti M. G., Perkowski J., Petrone C., Pirovano E., Plaza J., Pomp S., Porras I., Praena J., Quesada J. M., Reifarth R., Rochman D., Romanets Y., Rubbia C., Sánchez-Caballero A., Sabaté-Gilarte M., Schillebeeckx P., Sekhar A., Smith A. G., Sosnin N. V., Stamati M. E., Sturniolo A., Tagliente G., Tarrío D., Torres-Sánchez P., Vagena E., Valenta S., Variale V., Vaz P., Vecchio G., Vescovi D., Vlachoudis V., Vlastou R., Wallner A., Woods P. J., Wright T., Zarrella R., and Žugec P.
Subjects: Physics, QC1-999
Abstract: Neutron capture cross-section measurements are fundamental in the study of astrophysical phenomena, such as the slow neutron capture (s-) process of nucleosynthesis operating in red-giant and massive stars. However, neutron capture measurements via the time-of-flight (TOF) technique on key s-process nuclei are often challenging. Difficulties arise from the limited mass (∼mg) available and the high sample-related background in the case of the unstable s-process branching points. Measurements on neutron magic nuclei, that act as s-process bottlenecks, are affected by low (n,γ) cross sections and a dominant neutron scattering background. Overcoming these experimental challenges requires the combination of facilities with high instantaneous flux, such as n_TOFEAR2, with detection systems with an enhanced detection sensitivity and high counting rate capabilities. This contribution reviews some of the latest detector developments in detection systems for (n,γ) measurements at n_TOF, such as i-TED, an innovative detection system which exploits the Compton imaging technique to reduce the dominant neutron scattering background and s-TED, a highly segmented total energy detector intended for high flux facilities. The discussion will be illustrated with results of the first measurement of key the s-process branching-point reaction 79Se(n,γ).
Published: 2023
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19. Study of decay properties for Ba to Nd nuclei relevant for the formation of the r-process rare-earth peak (A∼160)

Author: Pallàs M., Tarifeño-Saldivia A., Kiss G. G., Tain J. L., Tolosa-Delgado A., Vitéz-Sveiczer A., Calviño F., Agramunt J., Aguilera P., Algora A., Allmond J. M., Baba H., Brewer N. T., Caballero-Folch R., Coleman-Smith P. J., Cortes G., Davinson T., Dillmann I., Domingo-Pardo C., Estrade A., Fukuda N., Go S., Griffin C. J., Grzywacz R. K., Hall O., Harkness-Brennan L. J., Isobe T., Kahl D., King T. T., Korgul A., Kovács S., Kubono S., Labiche M., Liu J., Madurga M., Miernik K., Molina F., Mont-Geli N., Morales A. I., Nácher E., Navarro A., Nepal N., Nishimura S., Piersa-Silkowska M., Phong V., Rasco B. C., Romero-Barrientos J., Rubio B., Rykaczewski K. P., Saito Y., Sakurai H., Shimizu Y., Singh M., Sumikama T., Suzuki H., Szegedi T. N., Takeda H., Wang K., Wolińska-Cichocka M., Woods P. J., and Yokoyama R.
Subjects: Physics, QC1-999
Abstract: At the RIKEN Nishina Center, exotic neutron-rich isotopes of Ba, La, Ce, Pr, and Nd were measured. This work reports their half-lives (T1/2) and β-delayed neutron-emission probabilities (Pxn). The setup consisted of the BigRIPS in-flight separator for particle identification, the Advanced Implantation Detector Array (AIDA) for ions and β detection, and the BRIKEN neutron counter for neutron detection. Using this arrangement, 4 new T1/2 and 14 new P1n were measured. Furthermore, 38 T1/2 and 2 P1n values were remeasured, decreasing the uncertainties for some of them. In addition to improving predictions of nucleosynthesis models that describe the production of the rare-earth peak at A ∼ 160 via the r-process, these additional experimental data should help to constrain theoretical models for calculations of T1/2 and Pxn in this region.
Published: 2023
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20. Shape-persistent ladder molecules exhibit nanogap-independent conductance in single-molecule junctions

Author: Liu, Xiaolin, Yang, Hao, Harb, Hassan, Samajdar, Rajarshi, Woods, Toby J., Lin, Oliver, Chen, Qian, Romo, Adolfo I. B., Rodríguez-López, Joaquín, Assary, Rajeev S., Moore, Jeffrey S., and Schroeder, Charles M.
Published: 2024
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21. Neurocognitive correlates of cerebral mitochondrial function and energy metabolism using phosphorus magnetic resonance spectroscopy in older adults

Author: Lopez, Francesca V., O’Shea, Andrew, Huo, Zhiguang, DeKosky, Steven T., Trouard, Theodore P., Alexander, Gene E., Woods, Adam J., and Bowers, Dawn
Published: 2024
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22. Facilitation of working memory capacity by transcranial direct current stimulation: a secondary analysis from the augmenting cognitive training in older adults (ACT) study

Author: Aksu, Serkan, Indahlastari, Aprinda, O’Shea, Andrew, Marsiske, Michael, Cohen, Ronald, Alexander, Gene E., DeKosky, Steven T., Hishaw, Georg A., Dai, Yunfeng, Wu, Samuel S., and Woods, Adam J.
Published: 2024
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23. The path to contentless experience in meditation: An evidence synthesis based on expert texts

Author: Woods, Toby J., Windt, Jennifer M., and Carter, Olivia
Published: 2024
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24. First 80Se(n,γ) cross section measurement with high resolution in the full stellar energy range 1 eV - 100 keV and its astrophysical implications for the s-process

Author: Babiano-Suarez V., Balibrea-Correa J., Caballero-Ontanaya L., Domingo-Pardo C., Ladarescu I., Lerendegui-Marco J., Tain J. L., Calviño F., Casanovas A., Tarifeño-Saldivia A., Guerrero C., Aberle O., Alcayne V., Amaducci S., Andrzejewski J., Audouin L., Bacak M., Barbagallo M., Bennett S., Berthoumieux E., Billowes J., Bosnar D., Brown A., Busso M., Caamaño M., Calviani M., Cano-Ott D., Cerutti F., Chiaveri E., Colonna N., Cortés G., CortésGiraldo M. A., Cosentino L., Cristallo S., Damone L. A., Davies P. J., Diakaki M., Dietz M., Dressler R., Ducasse Q., Dupont E., Durán I., Eleme Z., Fernández-Domínguez B., Ferrari A., Finocchiaro P., Furman V., Göbel K., Garg R., Gawlik-Ramięga A., Gilardoni S., Gonçalves I. F., González-Romero E., Gunsing F., Harada H., Heinitz S., Heyse J., Jenkins D. G., Junghans A., Käppeler F., Kadi Y., Kimura A., Knapová I., Kokkoris M., Kopatch Y., Krtička M., Kurtulgil D., Lederer-Woods C., Leeb H., Lonsdale S. J., Macina D., Manna A., Martínez T., Masi A., Massimi C., Mastinu P., Mastromarco M., Maugeri E. A., Mazzone A., Mendoza E., Mengoni A., Michalopoulou V., Milazzo P. M., Mingrone F., Moreno-Soto J., Musumarra A., Negret A., Nolte R., Ogállar F., Oprea A., Patronis N., Pavlik A., Perkowski J., Persanti L., Petrone C., Pirovano E., Porras I., Praena J., Quesada J. M., Ramos-Doval D., Rauscher T., Reifarth R., Rochman D., Romanets Y., Rubbia C., Sabaté-Gilarte M., Saxena A., Schillebeeckx P., Schumann D., Sekhar A., Smith A. G., Sosnin N. V., Sprung P., Stamatopoulos A., Tagliente G., Tassan-Got L., Thomas Th., Torres-Sánchez P., 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., and Žugec P.
Subjects: Physics, QC1-999
Abstract: Most elements heavier than iron have been generated in the stellar media by means of neutron capture reactions, approximately half are produced by the slow neutron capture or s-process. Radiative neutron capture cross section measurements are of fundamental importance for the study of this mechanism. In this contribution we present a brief summary on the measurement and results for the 80Se(n,γ) cross-section. The experiment was carried out at CERN n_TOF EAR1 via the time of flight (ToF) technique, using four C6D6 scintillation detectors with very fast response. More than a hundred new resonances have been analyzed for the first time with a high accuracy. The MACS obtained at kT = 8 keV is 36% smaller than the recommended value in KADo-NiS. Some of the astrophysical implications of this result are elucidated in this contribution.
Published: 2022
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25. Magnetic field-temperature phase diagram of spin-1/2 triangular lattice antiferromagnet KYbSe$_2$

Author: Lee, Sangyun, Woods, Andrew J., Lee, Minseong, Zhang, Shengzhi, Choi, Eun Sang, Scheie, A. O., Tennant, D. A., Xing, J., Sefat, A. S., and Movshovich, R.
Subjects: Condensed Matter - Strongly Correlated Electrons, Condensed Matter - Materials Science
Abstract: A quantum spin liquid (QSL) is a state of matter characterized by fractionalized quasiparticle excitations, quantum entanglement, and a lack of long-range magnetic order. However, QSLs have evaded definitive experimental observation. Several Yb$^{3+}$-based triangular lattice antiferromagnets with effective $S$ = $\frac{1}{2}$ have been suggested to stabilize the QSL state as the ground state. Here, we build a comprehensive magnetic temperature phase diagram of a high-quality single crystalline KYbSe$_2$ via heat capacity and magnetocaloric effect down to 30 mK with magnetic field applied along the $a$-axis. At zero magnetic field, we observe the magnetic long-range order at $T_N$ = 0.29 K entering 120 degrees ordered state in heat capacity, consistent with neutron scattering studies. Analysis of the low-temperature ($T$) specific heat ($C$) at zero magnetic field indicates linear $T$-dependence of $C/T$ and a broad hump of $C/T$ in the proximate QSL region above $T_N$. By applying magnetic field, we observe the up-up-down phase with 1/3 magnetization plateau and oblique phases, in addition to two new phases. These observations strongly indicate that while KYbSe$_2$ closely exhibits characteristics resembling an ideal triangular lattice, deviations may exist, such as the effect of the next-nearest-neighbor exchange interaction, calling for careful consideration for spin Hamiltonian modeling. Further investigations into tuning parameters, such as chemical pressure, could potentially induce an intriguing QSL phase in the material.
Published: 2024

26. Semantic processing in older adults is associated with distributed neural activation which varies by association and abstractness of words

Author: Garcia, Amanda, Cohen, Ronald A., Langer, Kailey G., O’Neal, Alexandria G., Porges, Eric C., Woods, Adam J., and Williamson, John B.
Published: 2024
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27. Learning ratio performance on a brief visual learning and memory test moderates cognitive training gains in Double Decision task in healthy older adults

Author: Hardcastle, Cheshire, Kraft, Jessica N., Hausman, Hanna K., O’Shea, Andrew, Albizu, Alejandro, Evangelista, Nicole D., Boutzoukas, Emanuel M., Van Etten, Emily J., Bharadwaj, Pradyumna K., Song, Hyun, Smith, Samantha G., Porges, Eric, DeKosky, Steven T., Hishaw, Georg A., Wu, Samuel S., Marsiske, Michael, Cohen, Ronald, Alexander, Gene E., and Woods, Adam J.
Published: 2024
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28. Informing the design of fish-friendly shoreline retaining walls for freshwater systems

Author: Frempong-Manso, Acacia, Elvidge, Chris K., Woods, Sam J., Van de Riet, Keith, and Cooke, Steven J.
Published: 2024
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29. The impact of a tDCS and cognitive training intervention on task-based functional connectivity

Author: Kraft, Jessica N., Indahlastari, Aprinda, Boutzoukas, Emanuel M., Hausman, Hanna K., Hardcastle, Cheshire, Albizu, Alejandro, O’Shea, Andrew, Evangelista, Nicole D., Van Etten, Emily J., Bharadwaj, Pradyumna K., Song, Hyun, Smith, Samantha G., DeKosky, Steven T., Hishaw, Georg A., Wu, Samuel, Marsiske, Michael, Cohen, Ronald, Alexander, Gene E., Porges, Eric, and Woods, Adam J.
Published: 2024
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30. Frontal–temporal regional differences in brain energy metabolism and mitochondrial function using 31P MRS in older adults

Author: Lopez, Francesca V., O’Shea, Andrew, Huo, Zhiguang, DeKosky, Steven T., Trouard, Theodore P., Alexander, Gene E., Woods, Adam J., and Bowers, Dawn
Published: 2024
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31. Pushing the high count rate limits of scintillation detectors for challenging neutron-capture experiments

Author: Correa, J. Balibrea, Lerendegui-Marco, J., Babiano-Suarez, V., Domingo-Pardo, C., Ladarescu, I., Tarifeño-Saldivia, A., Alcayne, V., Cano-Ott, D., González-Romero, E., Martínez, T., Mendoza, E., de Rada, A. Pérez, del Olmo, J. Plaza, Sánchez-Caballero, A., Casanovas, A., Calviño, F., Valenta, S., Aberle, O., Altieri, S., Amaducci, S., Andrzejewski, J., Bacak, M., Beltrami, C., Bennett, S., Bernardes, A. P., Berthoumieux, E., Beyer, R., Boromiza, M., Bosnar, D., Caamaño, M., Calviani, M., Castelluccio, D. M., Cerutti, F., Cescutti, G., Chasapoglou, S., Chiaveri, E., Colombetti, P., Colonna, N., Camprini, P. Console, Cortés, G., Cortés-Giraldo, M. A., Cosentino, L., Cristallo, S., Dellmann, S., Di Castro, M., Di Maria, S., Diakaki, M., Dietz, M., Dressler, R., Dupont, E., Durán, I., Eleme, Z., Fargier, S., Fernández, B., Fernández-Domínguez, B., Finocchiaro, P., Fiore, S., Furman, V., García-Infantes, F., Gawlik-Ramikega, A., Gervino, G., Gilardoni, S., Guerrero, C., Gunsing, F., Gustavino, C., Heyse, J., Hillman, W., Jenkins, D. G., Jericha, E., Junghans, A., Kadi, Y., Kaperoni, K., Kaur, G., Kimura, A., Knapová, I., Kokkoris, M., Kopatch, Y., Krtička, M., Kyritsis, N., Lederer-Woods, C., Lerner, G., Manna, A., Masi, A., Massimi, C., Mastinu, P., Mastromarco, M., Maugeri, E. A., Mazzone, A., Mengoni, A., Michalopoulou, V., Milazzo, P. M., Mucciola, R., Murtas, F., Musacchio-Gonzalez, E., Musumarra, A., Negret, A., Pérez-Maroto, P., Patronis, N., Pavón-Rodríguez, J. A., Pellegriti, M. G., Perkowski, J., Petrone, C., Pirovano, E., Pomp, S., Porras, I., Praena, J., Quesada, J. M., Reifarth, R., Rochman, D., Romanets, Y., Rubbia, C., Sabaté-Gilarte, M., Schillebeeckx, P., Schumann, D., Sekhar, A., Smith, A. G., Sosnin, N. V., Stamati, M. E., Sturniolo, A., Tagliente, G., Tarrío, D., Torres-Sánchez, P., Vagena, E., Variale, V., Vaz, P., Vecchio, G., Vescovi, D., Vlachoudis, V., Vlastou, R., Wallner, A., Woods, P. J., Wright, T., Zarrella, R., and Žugec, P.
Subjects: Physics - Instrumentation and Detectors, Nuclear Experiment
Abstract: One of the critical aspects for the accurate determination of neutron capture cross sections when combining time-of-flight and total energy detector techniques is the characterization and control of systematic uncertainties associated to the measuring devices. In this work we explore the most conspicuous effects associated to harsh count rate conditions: dead-time and pile-up effects. Both effects, when not properly treated, can lead to large systematic uncertainties and bias in the determination of neutron cross sections. In the majority of neutron capture measurements carried out at the CERN n\_TOF facility, the detectors of choice are the C$_{6}$D$_{6}$ liquid-based either in form of large-volume cells or recently commissioned sTED detector array, consisting of much smaller-volume modules. To account for the aforementioned effects, we introduce a Monte Carlo model for these detectors mimicking harsh count rate conditions similar to those happening at the CERN n\_TOF 20~m fligth path vertical measuring station. The model parameters are extracted by comparison with the experimental data taken at the same facility during 2022 experimental campaign. We propose a novel methodology to consider both, dead-time and pile-up effects simultaneously for these fast detectors and check the applicability to experimental data from $^{197}$Au($n$,$\gamma$), including the saturated 4.9~eV resonance which is an important component of normalization for neutron cross section measurements.
Published: 2023

32. Anisotropic field-induced changes in the superconducting order parameter of UTe2

Author: Lee, Sangyun, Woods, Andrew J., Rosa, P. F. S., Thomas, S. M., Bauer, E. D., Lin, Shi-Zeng, and Movshovich, R.
Subjects: Condensed Matter - Superconductivity, Condensed Matter - Strongly Correlated Electrons
Abstract: UTe2 is a newly discovered unconventional superconductor, where electron Cooper pairs combine into a spin-triplet ground state. Here we report the specific heat C(H,T) of a high-quality single crystal of UTe2 with a single specific heat anomaly at the superconducting transition temperature T_c {\approx} 2 K and a small zero-field residual Sommerfeld coefficient {\gamma}_0 = C/T (T=0) = 10 mJ/mol-K^2. We applied magnetic field up to 12 T along the three principal crystallographic axes of UTe2 to probe the nature of the superconducting state. The evolution of the residual Sommerfeld coefficient as a function of magnetic field, {\gamma}_0 (H), is highly anisotropic and reveals distinct regions. In magnetic field up to 4 T applied along a, b, and c axes, we find {\gamma}_0{\approx}{\alpha}_i {\square}H, with i=a,b,c, as expected for an unconventional superconductor with nodes (zeros) of the superconducting order parameter on the Fermi surface. A pronounced kink in {\gamma}_0(H), however, is observed at roughly 4 T for field applied along both a and b axes, whereas a smooth change from square-root to linear behaviour is observed at 4 T for H//c. These results strongly indicate that a zero-field ground state is stable up to 4 T and undergoes a field-induced evolution above 4 T. {\alpha_c} > {\alpha_a} > {\alpha_b}, indicating that the nodes in the low-field state are predominantly located in the vicinity of the a-b plane. The modification of the order parameter is strongest when field is applied in the a-b plane, which causes nodes to move away from the direction of the applied field. Both d_(B_2u)+id_(B_1u) and d_(B_2u)+id_(A_u) two-component order parameters can account for our observations, with d_(B_2u)+id_(B_1u) a more likely candidate. In either scenario, our measurements indicate that B_2u is the primary superconducting order parameter in UTe2.
Published: 2023

33. Disorder and diffuse scattering in single-chirality (TaSe$_4$)$_2$I crystals

Author: Christensen, Jacob A., Bettler, Simon, Qu, Kejian, Huang, Jeffrey, Kim, Soyeun, Lu, Yinchuan, Zhao, Chengxi, Chen, Jin, Krogstad, Matthew J., Woods, Toby J., Mahmood, Fahad, Huang, Pinshane Y., Abbamonte, Peter, and Shoemaker, Daniel P.
Subjects: Condensed Matter - Strongly Correlated Electrons, Condensed Matter - Materials Science
Abstract: The quasi-one-dimensional chiral compound (TaSe$_4$)$_2$I has been extensively studied as a prime example of a topological Weyl semimetal. Upon crossing its phase transition temperature $T_\textrm{CDW}$ $\approx$ 263 K, (TaSe$_4$)$_2$I exhibits incommensurate charge density wave (CDW) modulations described by the well-defined propagation vector $\sim$(0.05, 0.05, 0.11), oblique to the TaSe$_4$ chains. Although optical and transport properties greatly depend on chirality, there is no systematic report about chiral domain size for (TaSe$_4$)$_2$I. In this study, our single-crystal scattering refinements reveal a bulk iodine deficiency, and Flack parameter measurements on multiple crystals demonstrate that separate (TaSe$_4$)$_2$I crystals have uniform handedness, supported by direct imaging and helicity dependent THz emission spectroscopy. Our single-crystal X-ray scattering and calculated diffraction patterns identify multiple diffuse features and create a real-space picture of the temperature-dependent (TaSe$_4$)$_2$I crystal structure. The short-range diffuse features are present at room temperature and decrease in intensity as the CDW modulation develops. These transverse displacements, along with electron pinning from the iodine deficiency, help explain why (TaSe$_4$)$_2$I behaves as an electronic semiconductor at temperatures above and below $T_\textrm{CDW}$, despite a metallic band structure calculated from density functional theory of the ideal structure., Comment: 25 pages, 20 figures, 5 tables
Published: 2023
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34. Actinium chelation and crystallization in a macromolecular scaffold

Author: Wacker, Jennifer N, Woods, Joshua J, Rupert, Peter B, Peterson, Appie, Allaire, Marc, Lukens, Wayne W, Gaiser, Alyssa N, Minasian, Stefan G, Strong, Roland K, and Abergel, Rebecca J
Subjects: Inorganic Chemistry, Chemical Sciences, 1.1 Normal biological development and functioning, Actinium, Chelating Agents, Crystallization, Radiopharmaceuticals, Humans, Ligands
Abstract: Targeted alpha therapy (TAT) pairs the specificity of antigen targeting with the lethality of alpha particles to eradicate cancerous cells. Actinium-225 [225Ac; t1/2 = 9.920(3) days] is an alpha-emitting radioisotope driving the next generation of TAT radiopharmaceuticals. Despite promising clinical results, a fundamental understanding of Ac coordination chemistry lags behind the rest of the Periodic Table due to its limited availability, lack of stable isotopes, and inadequate systems poised to probe the chemical behavior of this radionuclide. In this work, we demonstrate a platform that combines an 8-coordinate synthetic ligand and a mammalian protein to characterize the solution and solid-state behavior of the longest-lived Ac isotope, 227Ac [t1/2 = 21.772(3) years]. We expect these results to direct renewed efforts for 225Ac-TAT development, aid in understanding Ac coordination behavior relative to other +3 lanthanides and actinides, and more broadly inform this element's position on the Periodic Table.
Published: 2024

35. A better alpha - Incorporating spectral parameterization to improve measurement of listening effort

Author: Woods, Sarah J, Silcox, Jack W, and Payne, Brennan R
Subjects: Cognitive Neuroscience, Psychology, Language and thought, Perception, Electroencephalography (EEG)
Abstract: Understanding and quantifying listening effort (LE) is important to a better understanding of speech perception in acoustically challenging environments. EEG alpha power has shown promise as a measure of LE, but relationships between acoustic challenge and alpha have been inconsistent in prior work. We test whether these mixed findings are attributed to differences in alpha power measurement across studies. We compared traditional bandwidth measurement of alpha power to an algorithmic spectral parameterization (SP) approach which separates alpha from background changes in broadband aperiodic activity. Whereas the traditional approach yielded no significant difference in alpha between speech in quiet versus in background noise, the SP approach, which accounts for flattening of the broadband slope in noise, yielded a significant increase in alpha power to speech in noise. These results highlight the importance of accounting for aperiodic brain activity when considering oscillatory EEG markers of cognitive demand in speech perception.
Published: 2024

36. Measurement of the energy-differential cross-section of the 12C(n,p)12B and 12C(n,d)11B reactions at the n_TOF facility at CERN

Author: Barbagallo M., Aberle O., Alcayne V., Amaducci S., Andrzejewski J., Audouin L., Babiano-Suarez V, Bacak M., Bennett S., Berthoumieux E., Bosnar D., Brown A. S., Busso M., Caamaño M., Caballero L., Calviani M., Calviño F., Cano-Ott D, Casanovas A., Cerutti F., Chiaveri E., Colonna N., Cortés G. P., Cortés-Giraldo M. A., Cosentino L., Cristallo S., Damone L. A., Davies P. J., Diakaki M., Dietz M., Domingo-Pardo C, Dressler R., Ducasse Q., Dupont E., Durán I., Eleme Z., Fernández-Domíngez B., Ferrari A., Ferro-Gonçalves I., Finocchiaro P., Furman V., Garg R., Gawlik A., Gilardoni S., Göbel K., González-Romero E., Guerrero C., Gunsing F., Heinitz S., Heyse J., Jenkins D. G., Jericha E., Jiri U., Junghans A., Kadi Y., Käppeler F., Kimura A., Knapová I., Kokkoris M., Kopatch Y., Krtička M., Kurtulgil D., Ladarescu I., Lederer-Woods C, Lerendegui-Marco J, Lonsdale S.-J., Macina D., Manna A., Martínez T., Masi A., Massimi C., Mastinu P. F., Mastromarco M., Maugeri E., Mazzone A., Mendoza E., Mengoni A., Michalopoulou V., Milazzo P. M., Millán-Callado M. A., Mingrone F., Moreno-Soto J, Musumarra A., Negret A., Ogállar F., Oprea A., Patronis N., Pavlik A., Perkowski J., Petrone C., Piersanti L., Pirovano E., Porras I., Praena J., Quesada J. M., Ramos Doval D., Reifarth R., Rochman D., Rubbia C., Sabaté- Gilarte M., Saxena A., Schillebeeckx P., Schumann D., Sekhar A., Smith A. G., Sosnin N., Sprung P., Stamatopoulos A., Tagliente G., Tain J. L., Tarifeño-Saldivia A. E., Tassan-Got L, Thomas B., Torres-Sánchez P., Tsinganis A., 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. J., and Žugec P.
Subjects: Physics, QC1-999
Abstract: Although the 12C(n,p)12B and 12C(n,d)11B reactions are of interest in several fields of basic and applied Nuclear Physics the present knowledge of these two cross-sections is far from being accurate and reliable, with both evaluations and data showing sizable discrepancies. As part of the challenging n_TOF program on (n,cp) nuclear reactions study, the energy differential cross-sections of the 12C(n,p)12B and 12C(n,d)11 B reactions have been measured at CERN from the reaction thresholds up to 30 MeV neutron energy. Both measurements have been recently performed at the long flight-path (185 m) experimental area of the n_TOF facility at CERN using a pure (99.95%) rigid graphite target and two silicon telescopes. In this paper an overview of the experiment is presented together with a few preliminary results.
Published: 2020
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37. Measurement and analysis of 155,157Gd(n,γ) from thermal energy to 1 keV

Author: Massimi C., Aberle O., Andrzejewski J., Audouin L., Bacak M., Balibrea J., Barbagallo M., Bečvář F., Berthoumieux E., Billowes J., Bosnar D., Brown A., Caamaño M., Calviño F., Calviani M., Cano-Ott D, Cardella R., Casanovas A., Castelluccio D. M., Cerutti F., Chen Y. H., Chiaveri E., Clai G., Colonna N., Console Camprini P., Cortés G., Cortés-Giraldo M. A., Cosentino L., Damone L. A., Diakaki M., Domingo-Pardo C, Dressler R., Dupont E., Durán I., Fernández-Domínguez B., Ferrari A., Ferreira P., Finocchiaro P., Furman V., Göbel K., García A. R., Gawlik A., Gilardoni S., Glodariu T., Gonçalves I. F., González-Romero E., Griesmayer E., Guerrero C., Guglielmelli A., Gunsing F., Harada H., Heinitz S., Heyse J., Jenkins D. G., Jericha E., Käppeler F., Kadi Y., Kalamara A., Kavrigin P., Kimura A., Kivel N., Knapova I., Kokkoris M., Krtička M., Kurtulgil D., Leal-Cidoncha E, Lederer C., Leeb H., Lerendegui-Marco J, Lonsdale S. J., Macina D., Manna A., Marganiec J., Martínez T., Masi A., Mastinu P., Mastromarco M., Maugeri E. A., Mazzone A., Mendoza E., Mengoni A., Milazzo P. M., Mingrone F., Mucciola R., Musumarra A., Negret A., Nolte R., Oprea A., Patronis N., Pavlik A., Perkowski J., Porras I., Praena J., Quesada J. M., Radeck D., Rauscher T., Reifarth R., Rocchi F., Rubbia C., Ryan J. A., Sabaté-Gilarte M., Saxena A., Schillebeeckx P., Schumann D., Sedyshev P., Smith A. G., Sosnin N. V., Stamatopoulos A., Tagliente G., Tain J. L, Tarifeño-Saldivia A., Tassan-Got L, Valenta S., Vannini G., Variale V., Vaz P., Ventura A., Vlachoudis V., Vlastou R., Wallner A., Warren S., Weiss C., Woods P. J., Wright T., and Žugec P.
Subjects: Physics, QC1-999
Abstract: We have measured the capture cross section of the 155Gd and 157Gd isotopes between 0.025 eV and 1 keV. The capture events were recorded by an array of 4 C6D6 detectors, and the capture yield was deduced exploiting the total energy detection system in combination with the Pulse Height Weighting Techniques. Because of the large cross section around thermal neutron energy, 4 metallic samples of different thickness were used to prevent problems related to self-shielding. The samples were isotopically enriched, with a cross contamination of the other isotope of less than 1.14%. The capture yield was analyzed with an R-Matrix code to describe the cross section in terms of resonance parameters. Near thermal energies, the results are significantly different from evaluations and from previous time-of-flight experiments. The data from the present measurement at n_TOF are publicly available in the experimental nuclear reaction database EXFOR.
Published: 2020
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38. First results of the 241Am(n,f) cross section measurement at the Experimental Area 2 of the n_TOF facility at CERN

Author: Eleme Z., Patronis N., Stamatopoulos A., Tsinganis A., Kokkoris M., Michalopoulou V., Diakaki M., Vlastou R., Tassan-Got L, Colonna N., Heyse J., Barbagallo M., Mastromarco M., Macina D., Chiaveri E., Aberle O., Alcayne V., Amaducci S., Andrzejewski J., Audouin L., Babiano-Suarez V, Bacak M., Bennett S., Berthoumieux E., Bosnar D., Brown A. S., Busso M., Caamaño M., Caballero L., Calviani M., Calviño F., Cano-Ott D, Casanovas A., Cerutti F., Cortés G. P., Cortés-Giraldo M. A., Cosentino L., Cristallo S., Damone L. A., Davies P. J., Dietz M., Domingo-Pardo C, Dressler R., Ducasse Q., Dupont E., Durán I., Fernández-Domíngez B., Ferrari A., Ferro-Gonçalves I., Finocchiaro P., Furman V., Garg R., Gawlik A., Gilardoni S., Göbel K., González-Romero E., Guerrero C., Gunsing F., Heinitz S., Jenkins D. G., Jericha E., Jiri U., Junghans A., Kadi Y., Käppeler F., Kimura A., Knapová I., Kopatch Y., Krticˇka M., Kurtulgil D., Ladarescu I., Lederer-Woods C, Lerendegui-Marco J, Lonsdale S. J., Manna A., Martínez T., Masi A., Massimi C., Mastinu P. F., Maugeri E., Mazzone A., Mendoza E., Mengoni A., Milazzo P. M., Millán-Callado M. A., Mingrone F., Moreno-Soto J, Musumarra A., Negret A., Ogállar F., Oprea A., Pavlik A., Perkowski J., Petrone C., Piersanti L., Pirovano E., Porras I., Praena J., Quesada J. M., Ramos Doval D., Reifarth R., Rochman D., Rubbia C., Sabaté-Gilarte M., Saxena A., Schillebeeckx P., Schumann D., Sekhar A., Smith A. G., Sosnin N., Sprung P., Tagliente G., Tain J. L., Tarifeño-Saldivia A. E., Thomas B., Torres-Sánchez P., Urlass S., Valenta S., Vannini G., Variale V., Vaz P., Ventura A., Vescovi D., Vlachoudis V., Wallner A., Woods P. J., Wright T. J., and Žugec P.
Subjects: Physics, QC1-999
Abstract: Feasibility, design and sensitivity studies on innovative nuclear reactors that could address the issue of nuclear waste transmutation using fuels enriched in minor actinides, require high accuracy cross section data for a variety of neutron-induced reactions from thermal energies to several tens of MeV. The isotope 241Am (T1/2= 433 years) is present in high-level nuclear waste (HLW), representing about 1.8 % of the actinide mass in spent PWR UOx fuel. Its importance increases with cooling time due to additional production from the β-decay of 241Pu with a half-life of 14.3 years. The production rate of 241 Am in conventional reactors, including its further accumulation through the decay of 241Pu and its destruction through transmutation/incineration are very important parameters for the design of any recycling solution. In the present work, the 241 Am(n,f) reaction cross-section was measured using Micromegas detectors at the Experimental Area 2 of the n_TOF facility at CERN. For the measurement, the 235U(n,f) and 238U(n,f) reference reactions were used for the determination of the neutron flux. In the present work an overview of the experimental setup and the adopted data analysis techniques is given along with preliminary results.
Published: 2020
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39. Accurate measurement of the standard 235U(n,f) cross section from thermal to 170 keV neutron energy

Author: Amaducci S., Aberle O., Andrzejewski J., Audouin L., Bacak M., Balibrea J., Barbagallo M., Bečvář F., Berthoumieux E., Billowes J., Bosnar D., Brown A., Caamaño M., Calviño F., Calviani M., Cano-Ott D, Cardella R., Casanovas A., Cerutti F., Chen Y. H., Chiaveri E., Colonna N., Cortés G., Cortés-Girardo M. A., Cosentino L., Damone L. A., Diakaki M., Domingo-Pardo C, Dressler R., Dupont E., Durán I., Fernández-Domínguez B., Ferrari A., Ferreira P., Finocchiaro P., Furman V., Göbel K., García A. R., Gawlik A., Gilardoni S., Glodariu T., Gonçalves I. F., González-Romero E., Griesmayer E., Guerrero C., Gunsing F., Harada H., Heinitz S., Heyse J., Jenkins D. G., Jericha E., Käppeler F., Kadi Y., Kalamara A., Kavrigin P., Kimura A., Kivel N., Knapova I., Kokkoris M., Krtička M., Kurtulgil D., Leal-Cidoncha E, Lederer C., Leeb H., Lerendegui-Marco J, Lo Meo S., Lonsdale S. J., Macina D., Manna A., Marganiec J., Martínez T., Masi A., Massimi C., Mastinu P., Mastromarco M., Maugeri E. A., Mazzone A., Mendoza E., Mengoni A., Milazzo P. M., Mingrone F., Musumarra A., Negret A., Nolte R., Oprea A., Patronis N., Pavlik A., Perkowski J., Porras I., Praena J., Quesada J. M., Radeck D., Rauscher T., Reifarth R., Rubbia C., Ryan J. A., Sabaté-Gilarte M., Saxena A., Schillebeeckx P., Schumann D., Sedyshev P., Smith A. G., Sosnin N. V., Stamatopoulos A., Tagliente G., Tain J. L., Tarifeño-Saldivia A., Tassan-Got L, Valenta S., Vannini G., Variale V., Vaz P., Ventura A., Vlachoudis V., Vlastou R., Wallner A., Warren S., Weiss C., Woods P. J., Wright T., and Žugec P.
Subjects: Physics, QC1-999
Abstract: An accurate measurement of the 235U(n,f) cross section from thermal to 170 keV of neutron energy has recently been performed at n_TOF facility at CERN using 6Li(n,t)4He and 10B(n,α)7Li as references. This measurement has been carried out in order to investigate a possible overestimation of the 235U fission cross section evaluation provided by most recent libraries between 10 and 30 keV. A custom experimental apparatus based on in-beam silicon detectors has been used, and a Monte Carlo simulation in GEANT4 has been employed to characterize the setup and calculate detectors efficiency. The results evidenced the presence of an overestimation in the interval between 9 and 18 keV and the new data may be used to decrease the uncertainty of 235U(n,f) cross section in the keV region.
Published: 2020
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40. Study of the neutron-induced fission cross section of 237Np at CERN's n_TOF facility over a wide energy range

Author: Stamatopoulos A., Tsinganis A., Diakaki M., Colonna N., Kokkoris M., Vlastou R., Kalamara A., Schillebeeckx P., Tassan-Got L, Žugec P., Sabaté-Gilarte M., Patronis N., Eleme Z., Heyse J., Aberle O., Andrzejewski J., Audouin L., Bacak M., Balibrea J., Barbagallo M., Bečvář F., Berthoumieux E., Billowes J., Bosnar D., Brown A., Caamaño M., Calviño F., Calviani M., Cano-Ott D, Cardella R., Casanovas A., Cerutti F., Chen Y. H., Chiaveri E., Cortés G., Cortés-Giraldo M. A., Cosentino L., Damone L. A., Domingo-Pardo C, Dressler R., Dupont E., Durán, Femandez-Domínguez B., Ferrari A., Ferreira P., Finocchiaro P., Furman V., Göbel K., García A. R., Gawlik A., Gilardoni S., Glodariu† T., Gonçalves I. F., González-Romero E., Griesmayer E., Guerrero C., Gunsing F., Harada H., Heinitz S., Jenkins D. G., Jericha E., Käppeler F., Kadi Y., Kavrigin P., Kimura A., Kivel N., Knapova I., Krtička M., Kurtulgil D., Leal-Cidoncha E, Lederer C., Leeb H., Lerendegui-Marco J, Meo S. Lo, Lonsdale S. J., Macina D., Manna A., Marganiec J., Martínez T., Masi A., Massimi C., Mastinu P., Mastromarco M., Maugeri E. A., Mazzone A., Mendoza E., Mengoni A., Milazzo P. M., Mingrone F., Musumarra A., Negret A., Nolte R., Oprea A., Pavlik A., Perkowski J., Porras I., Praena J., Quesada J. M., Radeck D., Rauscher T., Reifarth R., Rubbia C., Ryan J. A., Saxena A., Schumann D., Sedyshev P., Smith A. G., Sosnin N. V., Tagliente G., Tain J. L., Tarifeño-Saldivia A., Valenta S., Vannini G., Variale V., Vaz P., Ventura A., Vescovi D., Vlachoudis V., Wallner A., Warren S., Weiss C., Woods P. J., and Wright T.
Subjects: Physics, QC1-999
Abstract: Neutron-induced fission cross sections of isotopes involved in the nuclear fuel cycle are vital for the design and safe operation of advanced nuclear systems. Such experimental data can also provide additional constraints for the adjustment of nuclear model parameters used in the evaluation process, resulting in the further development of fission models. In the present work, the 237Np(n,f) cross section was studied at the EAR2 vertical beam-line at CERN's n_TOF facility, over a wide range of neutron energies, from meV to MeV, using the time-of-flight technique and a set-up based on Micromegas detectors, in an attempt to provide accurate experimental data. Preliminary results in the 200 keV – 14 MeV neutron energy range as well as the experimental procedure, including a description of the facility and the data handling and analysis, will be presented.
Published: 2020
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41. The 154Gd neutron capture cross section measured at the n_TOF facility and its astrophysical implications

Author: Mastromarco M., Mazzone A., Massimi C., Cristallo S., Colonna N., Aberle O., Alcayne V., Amaducci S., Andrzejewski J., Audouin L., Babiano-Suarez V, Bacak M., Barbagallo M., Bennett S., Berthoumieux E., Bosnar D., Brown A. S., Busso M., Caamaño M., Caballero L., Calviani M., Calviño F., Cano-Ott D, Casanovas A., Cerutti F., Chiaveri E., Cortés G. P., Cortés-Giraldo M. A., Cosentino L., Damone L. A., Davies P. J., Diakaki M., Dietz M., Domingo-Pardo C, Dressler R., Ducasse Q., Dupont E., Durán I., Eleme Z., Fernández-Domíngez B., Ferrari A., Ferro-Gonçalves I., Finocchiaro P., Furman V., Garg R., Gawlik A., Gilardoni S., Göbel K., González-Romero E., Guerrero C., Gunsing F., Heinitz S., Heyse J., Jenkins D. G., Jericha E., Jiri U., Junghans A., Kadi Y., Käppeler F., Kimura A., Knapová I., Kokkoris M., Kopatch Y., Krtička M., Kurtulgil D., Ladarescu I., Lederer-Woods C, Lerendegui-Marco J, Lonsdale S.-J., Macina D., Manna A., Martínez T., Masi A., Mastinu P. F., Maugeri E., Mendoza E., Mengoni A., Michalopoulou V., Milazzo P. M., Millán-Callado M. A., Mingrone F., Moreno-Soto J, Musumarra A., Negret A., Ogállar F., Oprea A., Patronis N., Pavlik A., Perkowski J., Petrone C., Piersanti L., Pirovano E., Porras I., Praena J., Quesada J. M., Doval D. Ramos, Reifarth R., Rochman D., Rubbia C., Sabaté-Gilarte M., Saxena A., Schillebeeckx P., Schumann D., Sekhar A., Smith A. G., Sosnin N., Sprung P., Stamatopoulos A., Tagliente G., Tain J. L., Tarifeño-Saldivia A. E., Tassan-Got L, Thomas B., Torres-Sánchez P., Tsinganis A., 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. J., and Žugec P.
Subjects: Physics, QC1-999
Abstract: The (n, γ) cross sections of the gadolinium isotopes play an important role in the study of the stellar nucleosynthesis. In particular, among the isotopes heavier than Fe, 154Gd together with 152Gd have the peculiarity to be mainly produced by the slow capture process, the so-called s-process, since they are shielded against the β-decay chains from the r-process region by their stable samarium isobars. Such a quasi pure s-process origin makes them crucial for testing the robustness of stellar models in galactic chemical evolution (GCE). According to recent models, the 154Gd and 152Gd abundances are expected to be 15-20% lower than the reference un-branched s-process 150Sm isotope. The close correlation between stellar abundances and neutron capture cross sections prompted for an accurate measurement of 154Gd cross section in order to reduce the uncertainty attributable to nuclear physics input and eventually rule out one of the possible causes of present discrepancies between observation and model predictions. To this end, the neutron capture cross section of 154Gd was measured in a wide neutron energy range (from thermal up to some keV) with high resolution in the first experimental area of the neutron time-of-flight facility n_TOF (EAR1) at CERN. In this contribution, after a brief description of the motivation and of the experimental setup used in the measurement, the preliminary results of the 154Gd neutron capture reaction as well as their astrophysical implications are presented.
Published: 2020
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42. Preliminary results on the 233U α-ratio measurement at n_TOF

Author: Bacak M., Aïche M., Bélier G., Berthoumieux E., Diakaki M., Dupont E., Gunsing F., Heyse J., Kopecky S., Krtička M., Laurent B., Leeb H., Mathieu L., Schillebeeckx P., Serot O., Taieb J., Valenta S., Vlachoudis V., Aberle O., Andrzejewski J., Audouin L., Balibrea J., Barbagallo M., Bečvář F., Billowes J., Bosnar D., Brown A., Caamaño M., Calviño F., Calviani, Cano-Ott D, Cardella R., Casanovas A., Cerutti F., Chen Y. H., Chiaveri E., Colonna, Cortés G., Cortés-Giraldo M. A., Cosentino L., Damone L. A., Domingo-Pardo C, Dressler R., Durán I., Fernández-Domínguez B., Ferrari A., Ferreira P., Finocchiaro P., Furman V., Göbel K., García A. R., Gawlik A., Gilardoni S., Glodariu T., Gonçalves I. F., González-Romero E., Griesmayer E., Guerrero C., Harada H., Heinitz S., Jenkins D. G., Jericha E., Käppeler F., Kadi Y., Kalamara A., Kavrigin P., Kimura A., Kivel N., Knapova I., Kokkoris M., Kurtulgil D., Leal-Cidoncha E, Lederer C., Lerendegui-Marco J, Meo S. Lo, Lonsdale S. J., Macina D., Manna A., Marganiec J., Martínez T., Masi A., Massimi C., Mastinu P., Mastromarco M., Maugeri E. A., Mazzone A., Mendoza E., Mengoni A., Milazzo P. M., Mingrone F., Musumarra A., Negret A., Nolte R., Oprea A., Patronis N., Pavlik A., Perkowski J., Porras I., Praena J., Quesada J. M., Radeck D., Rauscher T., Reifarth R., Rubbia C., Ryan J. A., Sabaté-Gilarte M., Saxena A., Schumann D., Sedyshev P., Smith A. G., Sosnin N. V., Stamatopoulos A., Tagliente G., Tain J. L., Tarifeño-Saldivia A., Tassan-Got L, Vannini G., Variale V., Vaz P., Ventura A., Vlastou R., Wallner A., Warren S., Weiss C., Woods P. J., Wright T., and Žugec P.
Subjects: Physics, QC1-999
Abstract: 233U is the fissile nuclei in the Th-U fuel cycle with a particularily small neutron capture cross setion which is on average about one order of magnitude lower than its fission cross section. Hence, the measurement of the 233U(n, γ) cross section relies on a method to accurately distinguish between capture and fission γ-rays. A measurement of the 233U α-ratio has been performed at the n_TOF facility at CERN using a so-called fission tagging setup, coupling n_TOF 's Total Absorption Calorimeter with a novel fission chamber to tag the fission γ-rays. The experimental setup is described and essential parts of the analysis are discussed. Finally, a preliminary 233U α-ratio is presented.
Published: 2020
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43. Setup for the measurement of the 235U(n, f) cross section relative to n-p scattering up to 1 GeV

Author: Manna A., Aberle O., Alcayne V, Amaducci S., Andrzejewski J., Audouin L., Babiano V-Suarez, Bacak M., Barbagallo M., Bennett S., Berthoumieux E., Bosnar D., Brown A. S., Busso M., Caamaño M., Caballero L., Calviani M., Calvi Fño, Cano-Ott D, Casanovas A., Cerutti F., Chiaveri E., Colonna N., Cortés G. P., Cortés-Giraldo M. A., Coséntino L., Cristallo S., Damone L. A., Davies P. J., Diakaki M., Dietz M., Domingo-Pardo C, Dressler R., Ducasse Q., Dupont E., Durán I., Eleme Z., Fernández-Domíngez B., Ferrari A., Ferro-Goncalves I, Finocchiaro P., Furman V., Garg R., Gawlik A., Gilardoni S., Göbel K., González-Romero E., Guerrero C., Gunsing F, Heinitz S., Heyse J., Jenkins D. G., Jericha E., Jiri U., Junghans A., Kadi Y, Käppeler F, Kimura A., Knapová I., Kokkoris M., Kopatch Y., Krtiička M., Kurtulgil D., Ladarescu I., Lederer-Woods C, Lerendegui-Marco J, Lonsdale S.-J., Macina D., Martínez T, Masi A., Massimi C., Mastinu P. F, Mastromarco M., Maugeri E., Mazzone A., Mendoza E., Mengoni A., Michalopoulou V, Milazzo P. M., Millán-Callado M. A., Mingrone F, Moreno-Soto J, Musumarra A., Negret A., Nolte R., Ogállar F, Oprea A., Patronis N., Pavlik A., Perkowski J., Petrone C., Piersanti L., Pirovano E., Porras I., Praena J., Quesada J.M., Ramos D., Reifarth R., Rochman D., Rubbia C., Sabaté-Gilarte M., Saxena A., Schillebeeckx P., Schumann D., Sekhar A., Smith A.G., Sosnin N., Sprung P., Stamatopoulos A., Tagliente G., Tain J. L., Tarifeno-Saldivia A. E., Tassan-Got L, Thomas B., Torres-Sánchez P., Tsinganis A., 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 J., and Žugec P.
Subjects: Physics, QC1-999
Abstract: The neutron induced fission of 235U is extensively used as a reference for neutron fluence measurements in various applications, ranging from the investigation of the biological effectiveness of high energy neutrons, to the measurement of high energy neutron cross sections of relevance for accelerator driven nuclear systems. Despite its widespread use, no data exist on neutron induced fission of 235U above 200 MeV. The neutron facility n_TOF offers the possibility to improve the situation. The measurement of 235U(n,f) relative to the differential n-p scattering cross-section, was carried out in September 2018 with the aim of providing accurate and precise cross section data in the energy range from 10 MeV up to 1 GeV. In such measurements, Recoil Proton Telescopes (RPTs) are used to measure the neutron flux while the fission events are detected and counted with dedicated detectors. In this paper the measurement campaign and the experimental set-up are illustrated.
Published: 2020
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44. Neutron capture cross section measurements of 241Am at the n_TOF facility

Author: Oprea A., Gunsing F., Schillebeeckx P., Aberle O., Bacak M., Berthoumieux E., Cano-Ott D, Diakaki M., Dupont E., Geslot B., Glodariu T., Heyse J., Mendoza E., Negret A., Alcayne V., Amaducci S., Andrzejewski J., Audouin L., Bécares V., Babiano-Suarez V, Barbagallo M., Becčvář F., Bellia G., Billowes J., Bosnar D., Brown A., Busso M., Caamaño M., Caballero-Ontanaya L, Calviño F., Calviani M., Casanovas A., Cerutti F., Chen Y. H., Chiaveri E., Colonna N., Cortés G., Cortés-Giraldo M. A., Cosentino L., Cristallo S., Damone L. A., Dietz M., Domingo-Pardo C, Dressler R., Durán I., Eleme Z., Femández-Domínguez B., Ferrari A., Finocchiaro P., Furman V., Göbel K., Garg R., Gawlik A., Gilardoni S., Goncalves I. F., González-Romero E., Guerrero C., Harada H., Heinitz S., Jenkins D. G., Jericha E., Käppeler F., Kadi Y., Kimura A., Kivel N., Kokkoris M., Kopatch Y., Krtička M., Kurtulgil D., Ladarescu I., Lederer-Woods C, Lerendegui-Marco J, Meo S. Lo, Lonsdale S. J., Macina D., Manna A., Martínez T., Masi A., Massimi C., Mastinu P., Mastromarco M., Matteucci F., Maugeri E. A., Mazzone A., Mengoni A., Michalopoulou V., Milazzo P. M., Mingrone F., Musumarra A., Nolte R., Ogállar F., Patronis N., Pavlik A., Perkowski J., Persanti L., Porras I., Praena J., Quesada J. M., Radeck D., Ramos-Doval D, Reifarth R., Rochman D., Rubbia C., Sabaté-Gilarte M., Saxena A., Schumann D., Smith A. G., Sosnin N. V., Stamatopoulos A., Tagliente G., Tain J. L., Talip T., Tarifeño-Saldivia A., Tassan-Got L, Torres-Sánchez P., Tsinganis A., Ulrich J., Urlass S., Valenta S., Vannini G., Variale V., Vaz P., Ventura A., Vlachoudis V., Vlastou R., Wallner A., Woods P. J., Wright T., and Žugec P.
Subjects: Physics, QC1-999
Abstract: Neutron capture on 241Am plays an important role in the nuclear energy production and also provides valuable information for the improvement of nuclear models and the statistical interpretation of the nuclear properties. A new experiment to measure the 241Am(n, γ) cross section in the thermal region and the first few resonances below 10 eV has been carried out at EAR2 of the n_TOF facility at CERN. Three neutron-insensitive C6D6 detectors have been used to measure the neutron-capture gamma cascade as a function of the neutron time of flight, and then deduce the neutron capture yield. Preliminary results will be presented and compared with previously obtained results at the same facility in EAR1. In EAR1 the gamma-ray background at thermal energies was about 90% of the signal while in EAR2 is up to a 25 factor much more favorable signal to noise ratio. We also extended the low energy limit down to subthermal energies. This measurement will allow a comparison with neutron capture measurements conducted at reactors and using a different experimental technique.
Published: 2020
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45. Measurement of the 244Cm capture cross sections at both CERN n_TOF experimental areas

Author: Alcayne V., Mendoza E., Cano-Ott D, Kimura A., Aberle O., Amaducci S., Andrzejewski J., Audouin L., Babiano-Suarez V, Bacak M., Barbagallo M., Bécares V., Bečvář F., Bellia G., Berthoumieux E., Billowes J., Bosnar D., Brown A. S., Busso M., Caamaño M., Caballero L., Calviani M., Calviño F., Casanovas A., Cerutti F., Chen Y. H., Chiaveri E., Colonna N., Cortés G. P., Cortés-Giraldo M. A., Cosentino L., Cristallo S., Damone L. A., Diakaki M., Dietz M., Domingo-Pardo C, Dressler R., Dupont E., Durán I., Eleme Z., Fernández-Domíngez B., Ferrari A., Ferro-Gonçalves I., Finocchiaro P., Furman V., Garg R., Gawlik A., Gilardoni S., Glodariu T., Göbel K., González-Romero E., Guerrero C., Gunsing F., Heinitz S., Heyse J., Jenkins D. G., Jericha E., Kadi Y., Käppeler F., Kivel N., Kokkoris M., Kopatch Y., Krtička M., Kurtulgil D., Ladarescu I., Lederer-Woods C, Lerendegui-Marco J, Lo Meo S., Lonsdale S.-J., Macina D., Manna A., Martínez T., Masi A., Massimi C., Mastinu P. F., Mastromarco M., Matteucci F., Maugeri E., Mazzone A., Mengoni A., Michalopoulou V., Milazzo P. M., Mingrone F., Musumarra A., Negret A., Nolte R., Ogállar F., Oprea A., Patronis N., Pavlik A., Perkowski J., Piersanti L., Porras I., Praena J., Quesada J. M., Radeck D., Ramos Doval D., Reifarth R., Rochman D., Rubbia C., Sabaté-Gilarte M., Saxena A., Schillebeeckx P., Schumann D., Smith A. G., Sosnin N., Stamatopoulos A., Tagliente G., Tain J. L., Talip Z., Tarifeño-Saldivia A. E., Tassan-Got L, Torres-Sánchez P., Tsinganis A., Ulrich J., Urlass S., Valenta S., Vannini G., Variale V., Vaz P., Ventura A., Vlachoudis V., Vlastou R., Wallner A., Woods P. J., Wright T. J., and Žugec P.
Subjects: Physics, QC1-999
Abstract: Accurate neutron capture cross section data for minor actinides (MAs) are required to estimate the production and transmutation rates of MAs in light water reactors with a high burnup, critical fast reactors like Gen-IV systems and other innovative reactor systems such as accelerator driven systems (ADS). Capture reactions of 244Cm open the path for the formation of heavier Cm isotopes and of heavier elements such as Bk and Cf. In addition, 244Cm shares nearly 50% of the total actinide decay heat in irradiated reactor fuels with a high burnup, even after three years of cooling. Experimental data for this isotope are very scarce due to the difficulties of providing isotopically enriched samples and because the high intrinsic activity of the samples requires the use of neutron facilities with high instantaneous flux. The only two previous experimental data sets for this neutron capture cross section have been obtained in 1969 using a nuclear explosion and, more recently, at J-PARC in 2010. The neutron capture cross sections have been measured at n_TOF with the same samples that the previous experiments in J-PARC. The samples were measured at n_TOF Experimental Area 2 (EAR-2) with three C6D6 detectors and also in Experimental Area 1 (EAR-1) with the Total Absorption Calorimeter (TAC). Preliminary results assessing the quality and limitations of these new experimental datasets are presented for the experiments in both areas. Preliminary yields of both measurements will be compared with evaluated libraries for the first time.
Published: 2020
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46. Measurement of the 242Pu(n, γ) cross section from thermal to 500 keV at the Budapest research reactor and CERN n_TOF-EAR1 facilities

Author: Lerendegui-Marco J, Guerrero C., Mendoza E., Quesada J. M., Eberhardt K., Junghans A., Krtiička M., Belgya T., Maróti B., Aberle O., Andrzejewski J., Audouin L., Bécares V., Bacak M., Balibrea J., Barbagallo M., Barros S., Bečvář F., Beinrucker C., Berthoumieux E., Billowes J., Bosnar D., Brugger M., Caamaño M., Calviño F., Calviani M., Cano-Ott D, Cardella R., Casanovas A., Castelluccio D. M., Cerutti F., Chen Y. H., Chiaveri E., Colonna N., Cortés G., Cortés-Giraldo M. A., Cosentino L., Damone L. A., Diakaki M., Domingo-Pardo C, Dressler R., Dupont E., Durán I., Fernández-Domínguez B., Ferrari A., Ferreira P., Finocchiaro P., Furman V., Göbel K., García A. R., Gawlik A., Glodariu T., Gonçalves I. F., González-Romero E., Goverdovski A., Griesmayer E., Gunsing F., Harada H., Heftrich T., Heinitz S., Heyse J., Jenkins D. G., Jericha E., Käppeler F., Kadi Y., Katabuchi T., Kavrigin P., Ketlerov V., Khryachkov V., Kimura A., Kivel N., Knapova I., Kokkoris M., Leal-Cidoncha E, Lederer C., Leeb H., Lo Meo S., Lonsdale S. J., Losito R., Macina D., Marganiec J., Martínez T., Massimi C., Mastinu P., Mastromarco M., Matteucci F., Maugeri E. A., Mengoni A., Milazzo P. M., Mingrone F., Mirea M., Montesano S., Musumarra A., Nolte R., Oprea A., Patronis N., Pavlik A., Perkowski J., Porras J. I., Praena J., Rajeev K., Rauscher T., Reifarth R., Riego-Perez A, Rout P. C., Rubbia C., Ryan J. A., Sabaté-Gilarte M., Saxena A., Schillebeeckx P., Schmidt S., Schumann D., Sedyshev P., Smith A. G., Stamatopoulos A., Tagliente G., Tain J. L., Tarifeño-Saldivia A., Tassan-Got L, Tsinganis A., Valenta S., Vannini G., Variale V., Vaz P., Ventura A., Vescovi D., Vlachoudis V., Vlastou R., Wallner A., Warren S., Weigand M., Weiss C., Wolf C., Woods P. J., Wright T., and Žugec P.
Subjects: Physics, QC1-999
Abstract: The design and operation of innovative nuclear systems requires a better knowledge of the capture and fission cross sections of the Pu isotopes. For the case of capture on 242Pu, a reduction of the uncertainty in the fast region down to 8-12% is required. Moreover, aiming at improving the evaluation of the fast energy range in terms of average parameters, the OECD NEA High Priority Request List (HPRL) requests high-resolution capture measurements with improved accuracy below 2 keV. The current uncertainties also affect the thermal point, where previous experiments deviate from each other by 20%. A fruitful collaboration betwen JGU Mainz and HZ Dresden-Rossendorf within the EC CHANDA project resulted in a 242Pu sample consisting of a stack of seven fission-like targets making a total of 95(4) mg of 242Pu electrodeposited on thin (11.5 μm) aluminum backings. This contribution presents the results of a set of measurements of the 242Pu(n, γ) cross section from thermal to 500 keV combining different neutron beams and techniques. The thermal point was determined at the Budapest Research Reactor by means of Neutron Activation Analysis and Prompt Gamma Analysis, and the resolved (1 eV - 4 keV) and unresolved (1 - 500 keV) resonance regions were measured using a set of four Total Energy detectors at the CERN n_TOF-EAR1.
Published: 2020
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47. Study of photon strength functions of 241Pu and 245Cm from neutron capture measurements

Author: Mendoza E., Alcayne V., Cano-Ott D, Kimura A., Skarbeli A. V., Aberle O., Amaducci S., Andrzejewski J., Audouin L., Babiano-Suarez V, Bacak M., Barbagallo M., Bécares V., Bečvář F., Bellia G., Berthoumieux E., Billowes J., Bosnar D., Brown A. S., Busso M., Caamaño M., Caballero L., Calviani M., Calviño F., Casanovas A., Cerutti F., Chen Y. H., Chiaveri E., Colonna N., Cortés G. P., Cortés-Giraldo M. A., Cosentino L., Cristallo S., Damone L. A., Diakaki M., Dietz M., Domingo-Pardo C, Dressler R., Dupont E., Durán I., Eleme Z., Fernández-Domíngez B., Ferrari A., Ferro-Gonçalves I., Finocchiaro P., Furman V., Garg R., Gawlik A., Gilardoni S., Glodariu T., Göbel K., González-Romero E., Guerrero C., Gunsing F., Heinitz S., Heyse J., Jenkins D. G., Jericha E., Kadi Y., Käppeler F., Kivel N., Kokkoris M., Kopatch Y., Krtička M., Kurtulgil D., Ladarescu I., Lederer-Woods C, Lerendegui-Marco J, Meo S. Lo, Lonsdale S.-J., Macina D., Manna A., Martínez T., Masi A., Massimi C., Mastinu P. F., Mastromarco M., Matteucci F., Maugeri E., Mazzone A., Mengoni A., Michalopoulou V., Milazzo P. M., Mingrone F., Musumarra A., Negret A., Nolte R., Ogállar F., Oprea A., Patronis N., Pavlik A., Perkowski J., Piersanti L., Porras I., Praena J., Quesada J. M., Radeck D., Doval D. Ramos, Reifarth R., Rochman D., Rubbia C., Sabaté-Gilarte M., Saxena A., Schillebeeckx P., Schumann D., Smith A. G., Sosnin N., Stamatopoulos A., Tagliente G., Tain J. L., Talip Z., Tarifeño-Saldivia A. E., Tassan-Got L, Torres-Sánchez P., Tsinganis A., Ulrich J., Urlass S., Valenta S., Vannini G., Variale V., Vaz P., Ventura A., Vlachoudis V., Vlastou R., Wallner A., Woods P. J., Wright T. J., and Žugec P.
Subjects: Physics, QC1-999
Abstract: We have measured the γ-rays following neutron capture on 240Pu and 244 Cm at the n_TOF facility at CERN with the Total Absorption Calorimeter (TAC) and with C6D6 organic scintillators. The TAC is made of 40 BaF2 crystals operating in coincidence and covering almost the entire solid angle. This allows to obtain information concerning the energy spectra and the multiplicity of the measured capture γ-ray cascades. Additional information is also obtained from the C6D6 detectors. We have analyzed the measured data in order to draw conclusions about the Photon Strength Functions (PSFs) of 241Pu and 245Cm below their neutron separation energies. The analysis has been performed by fitting the PSFs to the experimental results, using the differential evolution method, in order to find neutron capture cascades capable of reproducing at the same time a great variety of deposited energy spectra.
Published: 2020
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48. Monte Carlo simulations and n-p differential scattering data measured with Proton Recoil Telescopes

Author: Terranova N., Aberle O., Alcayne V., Amaducci S., Andrzejewski J., Audouin L., Babiano-Suarez V, Bacak M., Barbagallo M., Bennett S., Berthoumieux E., Bosnar D., Brown A. S., Busso M., Caamaño M., Caballero L., Calviani M., Calviño F., Cano-Ott D, Casanovas A., Cerutti F., Chiaveri E., Colonna N., Cortés G. P., Cortés-Giraldo M. A., Cosentino L., Cristallo S., Damone L. A., Davies P. J., Diakaki M., Dietz M., Domingo-Pardo C, Dressler R., Ducasse Q., Dupont E., Durán I., Eleme Z., Fernández-Domíngez B., Ferrari A., Ferro-Gonçalves I., Finocchiaro P., Furman V., Garg R., Gawlik A., Gilardoni S., Göbel K., González-Romero E., Guerrero C., Gunsing F., Heinitz S., Heyse J., Jenkins D. G., Jericha E., Jiri U., Junghans A., Kadi Y., Käppeler F., Kimura A., Knapová I., Kokkoris M., Kopatch Y., Krtička M., Kurtulgil D., Ladarescu I., Lederer-Woods C, Lerendegui-Marco J, Lonsdale S.-J., Macina D., Manna A., Martínez T., Masi A., Massimi C., Mastinu P. F., Mastromarco M., Maugeri E., Mazzone A., Mendoza E., Mengoni A., Michalopoulou V., Milazzo P. M., Millán-Callado M. A., Mingrone F., Moreno-Soto J, Musumarra A., Negret A., Ogállar F., Oprea A., Patronis N., Pavlik A., Perkowski J., Petrone C., Piersanti L., Pirovano E., Porras I., Praena J., Quesada J. M., Doval D. Ramos, Reifarth R., Rochman D., Rubbia C., Sabaté-Gilarte M., Saxena A., Schillebeeckx P., Schumann D., Sekhar A., Smith A. G., Sosnin N., Sprung P., Stamatopoulos A., Tagliente G., Tain J. L., Tarifeño-Saldivia A. E., Tassan-Got L, Thomas B., Torres-Sánchez P., Tsinganis A., 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. J., and Žugec P.
Subjects: Physics, QC1-999
Abstract: The neutron-induced fission cross section of 235U, a standard at thermal energy and between 0.15 MeV and 200 MeV, plays a crucial role in nuclear technology applications. The long-standing need of improving cross section data above 20 MeV and the lack of experimental data above 200 MeV motivated a new experimental campaign at the n_TOF facility at CERN. The measurement has been performed in 2018 at the experimental area 1 (EAR1), located at 185 m from the neutron-producing target (the experiment is presented by A. Manna et al. in a contribution to this conference). The 235U(n,f) cross section from 20 MeV up to about 1 GeV has been measured relative to the 1H(n,n)1H reaction, which is considered the primary reference in this energy region. The neutron flux impinging on the 235U sample (a key quantity for determining the fission events) has been obtained by detecting recoil protons originating from n-p scattering in a C2H4 sample. Two Proton Recoil Telescopes (PRT), consisting of several layers of solid-state detectors and fast plastic scintillators, have been located at proton scattering angles of 25.07° and 20.32°, out of the neutron beam. The PRTs exploit the ΔE-E technique for particle identification, a basic requirement for the rejection of charged particles from neutron-induced reactions in carbon. Extensive Monte Carlo simulations were performed to characterize proton transport through the different slabs of silicon and scintillation detectors, to optimize the experimental set-up and to deduce the efficiency of the whole PRT detector. In this work we compare measured data collected with the PRTs with a full Monte Carlo simulation based on the Geant-4 toolkit.
Published: 2020
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49. First results of the 230Th(n,f) cross section measurements at the CERN n_TOF facility

Author: Michalopoulou V., Stamatopoulos A., Vlastou R., Kokkoris M., Tsinganis A., Diakaki M., Eleme Z., Patronis N., Heyse J., Schillebeeckx P., Tassan-Got L, Barbagallo M., Colonna N., Urlass S., Macina D., Chiaveri E., Aberle O., Alcayne V., Amaducci S., Andrzejewski J., Audouin L., Babiano-Suarez V, Bacak M., Bennett S., Berthoumieux E., Bosnar D., Brown A. S., Busso M., Caamaño M., Caballero L., Calviani M., Calviño F., Cano-Ott D, Casanovas A., Cerutti F., Cortés G. P., Cortés-Giraldo M. A., Cosentino L., Cristallo S., Damone L. A., Davies P. J., Dietz M., Domingo-Pardo C, Dressler R., Ducasse Q., Dupont E., Durán I., Femández-Domíngez B., Ferrari A., Ferro-Gonçalves I., Finocchiaro P., Furman V., Garg R., Gawlik A., Gilardoni S., Göbel K., González-Romero E., Guerrero C., Gunsing F., Heinitz S., Jenkins D. G., Jericha E., Jiri U., Junghans A., Kadi Y., Käppeler F., Kimura A., Knapová I., Kopatch Y., Krtiička M., Kurtulgil D., Ladarescu I., Lederer-Woods C, Lerendegui-Marco J, Lonsdale S.-J., Manna A., Martínez T., Masi A., Massimi C., Mastinu P. F., Mastromarco M., Maugeri E., Mazzone A., Mendoza E., Mengoni A., Milazzo P. M., Millán-Callado M. A., Mingrone F., Moreno-Soto J, Musumarra A., Negret A., Ogállar F., Oprea A., Pavlik A., Perkowski J., Petrone C., Piersanti L., Pirovano E., Porras I., Praena J., Quesada J. M., Ramos Doval D., Reifarth R., Rochman D., Rubbia C., Sabaté-Gilarte M., Saxena A., Schumann D., Sekhar A., Smith A. G., Sosnin N., Sprung P., Tagliente G., Tain J. L., Tarifeño-Saldivia A. E., Thomas B., Torres-Sánchez P., Valenta S., Vannini G., Variale V., Vaz P., Ventura A., Vescovi D., Vlachoudis V., Wallner A., Woods P. J., Wright T. J., and Žugec P.
Subjects: Physics, QC1-999
Abstract: The study of neutron-induced reactions on actinides is of considerable importance for the design of advanced nuclear systems and alternative fuel cycles. Specifically, 230Th is produced from the α-decay of 234U as a byproduct of the 232Th/233U fuel cycle, thus the accurate knowledge of its fission cross section is strongly required. However, few experimental datasets exist in literature with large deviations among them, covering the energy range between 0.2 to 25 MeV. In addition, the study of the 230Th(n,f) cross-section is of great interest in the research on the fission process related to the structure of the fission barriers. Previous measurements have revealed a large resonance at En=715 keV and additional fine structures, but with high discrepancies among the cross-section values of these measurements. This contribution presents preliminary results of the 230Th(n,f) cross-section measurements at the CERN n_TOF facility. The high purity targets of the natural, but very rare isotope 230Th, were produced at JRC-Geel in Belgium. The measurements were performed at both experimental areas (EAR-1 and EAR-2) of the n_TOF facility, covering a very broad energy range from thermal up to at least 100 MeV. The experimental setup was based on Micromegas detectors with the 235U(n,f) and 238U(n,f) reaction cross-sections used as reference.
Published: 2020
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50. DOMINO++: Domain-aware Loss Regularization for Deep Learning Generalizability

Author: Stolte, Skylar E., Volle, Kyle, Indahlastari, Aprinda, Albizu, Alejandro, Woods, Adam J., Brink, Kevin, Hale, Matthew, and Fang, Ruogu
Subjects: Computer Science - Computer Vision and Pattern Recognition, Computer Science - Machine Learning, Electrical Engineering and Systems Science - Image and Video Processing
Abstract: Out-of-distribution (OOD) generalization poses a serious challenge for modern deep learning (DL). OOD data consists of test data that is significantly different from the model's training data. DL models that perform well on in-domain test data could struggle on OOD data. Overcoming this discrepancy is essential to the reliable deployment of DL. Proper model calibration decreases the number of spurious connections that are made between model features and class outputs. Hence, calibrated DL can improve OOD generalization by only learning features that are truly indicative of the respective classes. Previous work proposed domain-aware model calibration (DOMINO) to improve DL calibration, but it lacks designs for model generalizability to OOD data. In this work, we propose DOMINO++, a dual-guidance and dynamic domain-aware loss regularization focused on OOD generalizability. DOMINO++ integrates expert-guided and data-guided knowledge in its regularization. Unlike DOMINO which imposed a fixed scaling and regularization rate, DOMINO++ designs a dynamic scaling factor and an adaptive regularization rate. Comprehensive evaluations compare DOMINO++ with DOMINO and the baseline model for head tissue segmentation from magnetic resonance images (MRIs) on OOD data. The OOD data consists of synthetic noisy and rotated datasets, as well as real data using a different MRI scanner from a separate site. DOMINO++'s superior performance demonstrates its potential to improve the trustworthy deployment of DL on real clinical data., Comment: 12 pages, 5 figures, 5 tables, Accepted by the International Conference on Medical Image Computing and Computer Assisted Intervention (MICCAI) 2023
Published: 2023

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