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94 results on '"Cortes G. P."'

1. $\beta$-delayed neutron spectroscopy of $^{85, 86}$As with MONSTER at IGISOL

Author

Fiol, A. Pérez de Rada, Martínez, T., Cano-Ott, D., Penttilä, H., Agramunt, J., Alcayne, V., Algora, A., Alhomaidhi, S., Äystö, J., Banerjee, K., Beliuskina, O., Benito, J., Bhattacharya, C., Calviño, F., Cortés, G., de Groote, R. P., de Roubin, A., Delafosse, C., Domingo-Pardo, C., Geldhof, S., Gins, W., Hukkanen, M., Jokinen, A., Kankainen, A., Lerendegui-Marco, J., Gamonoso, J. Llanes, Matea, I., Mendoza, E., Mistry, A. K., Nesterenko, D. A., Plaza, J., Pohjalainen, I., Rinta-Antila, S., Roy, P., Sanchez-Caballero, A., Taín, J. L., Villamarín, D., and Vilen, M.

Subjects
Nuclear Experiment
Abstract

The $\beta$-delayed neutron emission in the $^{85, 86}$As $\beta$-decays has been measured at the Ion Guide Isotope Separator On Line facility of the Accelerator Laboratory of the University of Jyv\"askyl\"a. The complete $\beta$-decays have been studied with a complex setup that consists of a plastic scintillator for $\beta$-particles, MONSTER -- the MOdular Neutron time-of-flight SpectromeTER -- for neutrons, and a high-purity germanium and four LaBr$_3$ crystals for $\gamma$-rays. The $\beta$-delayed neutron energy distributions have been determined by unfolding the time-of-flight spectra with an innovative methodology based on the iterative Bayesian unfolding method and accurate Monte Carlo simulations. The results obtained for $^{85}$As are in excellent agreement with the existing evaluated data, validating the proposed methodology. In the case of $^{86}$As, a stronger neutron intensity at higher energies than previously predicted is discovered., Comment: 10 pages, 11 figures, to be submitted to Physical Review C

Published
2025

2. Radiative neutron capture cross section of $^{242}$Pu measured at n_TOF-EAR1 in the unresolved resonance region up to 600 keV

Author

Lerendegui-Marco, J., Guerrero, C., Mendoza, E., Quesada, J. M., Eberhardt, K., Junghans, A. R., Alcayne, V., Babiano, V., Aberle, O., Andrzejewski, J., Audouin, L., Becares, V., Bacak, M., Balibrea-Correa, J., Barbagallo, M., Barros, S., Becvar, 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., Dietz, 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., Goncalves, 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., Kokkoris, M., Krticka, M., Leal-Cidoncha, E., Lederer-Woods, C., Leeb, H., Meo, S. Lo, 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., Vlachoudis, V., Vlastou, R., Wallner, A., Warren, S., Weigand, M., Weiss, C., Wolf, C., Woods, P. J., Wright, T., Zugec, P., and Collaboration, the n_TOF

Subjects
Nuclear Experiment
Abstract

The design of fast reactors burning MOX fuels requires accurate capture and fission cross sections. For the particular case of neutron capture on 242Pu, the NEA recommends that an accuracy of 8-12% should be achieved in the fast energy region (2 keV-500 keV) compared to their estimation of 35% for the current uncertainty. Integral irradiation experiments suggest that the evaluated cross section of the JEFF-3.1 library overestimates the 242Pu(n,{\gamma}) cross section by 14% in the range between 1 keV and 1 MeV. In addition, the last measurement at LANSCE reported a systematic reduction of 20-30% in the 1-40 keV range relative to the evaluated libraries and previous data sets. In the present work this cross section has been determined up to 600 keV in order to solve the mentioned discrepancies. A 242Pu target of 95(4) mg enriched to 99.959% was irradiated at the n TOF-EAR1 facility at CERN. The capture cross section of 242Pu has been obtained between 1 and 600 keV with a systematic uncertainty (dominated by background subtraction) between 8 and 12%, reducing the current uncertainties of 35% and achieving the accuracy requested by the NEA in a large energy range. The shape of the cross section has been analyzed in terms of average resonance parameters using the FITACS code as implemented in SAMMY, yielding results compatible with our recent analysis of the resolved resonance region.The results are in good agreement with the data of Wisshak and K\"appeler and on average 10-14% below JEFF-3.2 from 1 to 250 keV, which helps to achieve consistency between integral experiments and cross section data. At higher energies our results show a reasonable agreement within uncertainties with both ENDF/B-VII.1 and JEFF-3.2. Our results indicate that the last experiment from DANCE underestimates the capture cross section of 242Pu by as much as 40% above a few keV., Comment: 20 pages, 19 figures, submitted to Phys. Rev. C

Published
2024

3. Towards a new generation of solid total-energy detectors for neutron-capture time-of-flight experiments with intense neutron beams

Author

Balibrea-Correa, J., Babiano-Suarez, V., Lerendegui-Marco, J., Domingo-Pardo, C., Ladarescu, I., Tarifeño-Saldivia, A., de la Fuente-Rosales, G., Gameiro, B., Zaitseva, N., 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., Krtìvcka, 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 Zugec, P.

Subjects
Physics - Instrumentation and Detectors, Nuclear Experiment
Abstract

Challenging neutron-capture cross-section measurements of small cross sections and samples with a very limited number of atoms require high-flux time-of-flight facilities. In turn, such facilities need innovative detection setups that are fast, have low sensitivity to neutrons, can quickly recover from the so-called $\gamma$-flash, and offer the highest possible detection sensitivity. In this paper, we present several steps toward such advanced systems. Specifically, we describe the performance of a high-sensitivity experimental setup at CERN n\_TOF EAR2. It consists of nine sTED detector modules in a compact cylindrical configuration, two conventional used large-volume C$_{6}$D$_{6}$ detectors, and one LaCl$_{3}$(Ce) detector. The performance of these detection systems is compared using $^{93}$Nb($n$,$\gamma$) data. We also developed a detailed \textsc{Geant4} Monte Carlo model of the experimental EAR2 setup, which allows for a better understanding of the detector features, including their efficiency determination. This Monte Carlo model has been used for further optimization, thus leading to a new conceptual design of a $\gamma$ detector array, STAR, based on a deuterated-stilbene crystal array. Finally, the suitability of deuterated-stilbene crystals for the future STAR array is investigaged experimentally utilizing a small stilbene-d12 prototype. The results suggest a similar or superior performance of STAR with respect to other setups based on liquid-scintillators, and allow for additional features such as neutron-gamma discrimination and a higher level of customization capability.

Published
2024

4. 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
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5. 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

6. Commissioning of miniBELEN-10A, a moderated neutron counter with a flat efficiency for thick-target neutron yields measurements

Author

Mont-Geli, N, Tarifeño-Saldivia, A, Fraile, L M, Viñals, S, Perea, A, Pallàs, M, Cortés, G, Garcia, G, Nácher, E, Tain, J L, Alcayne, V, Alonso-Sañudo, O, Algora, A, Balibrea-Correa, J, Benito, J, Borge, M J G, Briz, J A, Calviño, F, Cano-Ott, D, De Blas, A, Domingo-Pardo, C, Fernández, B, Garcia, R, Gómez-Camacho, J, González-Romero, E M, Guerrero, C, Lerendegui-Marco, J, Llanos, M, Martínez, T, Martínez-Nouvilas, V, Mendoza, E, Murias, J R, Orrigo, S E A, de Rada, A Pérez, Pesudo, V, Plaza, J, Quesada, J M, Sánchez, A, Sánchez-Tembleque, V, Santorelli, R, Tengblad, O, Udías, J M, and Villamarín, D

Subjects
Physics - Instrumentation and Detectors, Nuclear Experiment
Abstract

miniBELEN-10A is a modular and transportable moderated neutron counter with a nearly flat detection efficiency up to 8 MeV. The detector was designed to carry out measurements of (alpha, n) reactions in the context of the Measurement of Alpha Neutron Yields (MANY) project. In this work we present the results of the commissioning of miniBELEN-10A using the relatively well-known thick-target neutron yields from 27Al(alpha, n)30P.

Published
2023

7. miniBELEN: a modular neutron counter for (alpha,n) reactions

Author

Mont-Geli, N, Tarifeño-Saldivia, A, Fraile, L M, Viñals, S, Perea, A, Pallàs, M, Cortés, G, Nácher, E, Tain, J L, Alcayne, V, Algora, A, Balibrea-Correa, J, Benito, J, Borge, M J G, Briz, J A, Calviño, F, Cano-Ott, D, De Blas, A, Domingo-Pardo, C, Fernández, B, Garcia, R, García, G, Gómez-Camacho, J, González-Romero, E M, Guerrero, C, Lerendegui-Marco, J, Llanos, M, Martínez, T, Mendoza, E, Murias, J R, Orrigo, S E A, de Rada, A Pérez, Pesudo, V, Plaza, J, Quesada, J M, Sánchez, A, Sánchez-Tembleque, V, Santorelli, R, Tengblad, O, Udías, J M, and Villamarín, D

Subjects
Physics - Instrumentation and Detectors, Nuclear Experiment
Abstract

miniBELEN is a modular and transportable neutron moderated counter with a nearly flat neutron detection efficiency up to 10 MeV. Modularity implies that the moderator can be reassembled in different ways in order to obtain different types of response. The detector has been developed in the context of the Measurement of Alpha Neutron Yields (MANY) collaboration, which is a scientific effort aiming to carry out measurements of (alpha,n) production yields, reaction cross-sections and neutron energy spectra. In this work we present and discuss several configurations of the miniBELEN detector. The experimental validation of the efficiency calculations using 252Cf sources and the measurement of the 27Al(alpha,n)30P reaction is also presented., Comment: 15th International Conference on Nuclear Data for Science and Technology (ND2022)

Published
2023
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8. First measurement of the $^{94}$Nb($n$,$\gamma$) cross section at the CERN n\_TOF facility

Author

Balibrea-Correa, J., Babiano-Suarez, V., Lerendegui-Marco, J., Domingo-Pardo, C., Ladarescu, I., Tarifeño-Saldivia, A., Alcayne, V., Cano-Ott, D., González-Romero, E., Martínez, T., Mendoza, E., Plaza, J., Sánchez-Caballero, A., Calviño, F., Casanovas, A., Guerrero, C., Heinitz, S., Köster, U., Maugeri, E. A., Dressler, R., Schumann, D., Mönch, I., Cristallo, S., Lederer-Woods, C., Aberle, O., Altieri, S., Amaducci, S., Andrzejewski, J., Bacak, M., Beltrami, C., Bennett, S., Bernardes, A. P., Berthoumieux, E., Boromiza, M., Bosnar, D., Caamaño, M., Calviani, M., Cerutti, F., Cescutti, G., Chasapoglou, S., Chiaveri, E., Colombetti, P., Colonna, N., Camprini, P. Console, Cortés, G., Cortés-Giraldo, M. A., Cosentino, L., 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., Furman, V., 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., Kopatch, Y., Krtička, M., Kyritsis, N., 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., de Rada, A. Pérez, 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., 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., Žugec, P., and Collaboration, the n_TOF

Subjects
Nuclear Experiment
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 $^{94}$Nb, the $^{94}$Nb($n$,$\gamma$) cross-section could play a role in the determination of the $s$-process production of $^{94}$Mo in AGB stars, which presently cannot be reproduced by state-of-the-art stellar models. There are no previous $^{94}$Nb($n$,$\gamma$) experimental data for the resolved and unresolved resonance regions mainly due to the difficulties in producing high-quality 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 $^{94}$Nb($n$,$\gamma$) 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 $^{94}$Nb-sample. The latter was based on hyper-pure $^{93}$Nb 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 C$_{6}$D$_{6}$ detectors and a high-resolution LaCl$_{3}$(Ce)-detector, which will be employed for addressing reliably systematic effects and uncertainties.At the current status of the data analysis, 18 resonance in $^{94}$Nb+$n$ have been observed for the first time in the neutron energy range from thermal up to 10 keV., Comment: NPA-X conference proceeding

Published
2023
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9. Measurement of the $^{14}$N(n,p)$^{14}$C cross section at the CERN n_TOF facility from sub-thermal energy to 800 keV

Author

Torres-Sánchez, P., Praena, J., Porras, I., Sabaté-Gilarte, M., Lederer-Woods, C., Aberle, O., Alcayne, V., 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, L., Calviño, F., Calviani, M., Cano-Ott, D., 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-Domínguez, B., Ferrari, A., Ferrer, F. J., Finocchiaro, P., Furman, V., Göbel, K., Garg, R., Gawlik-Ramięga, A., Geslot, B., 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., Kimura, A., Kivel, N., Kokkoris, M., Kopatch, Y., Krtička, M., Kurtulgil, D., Ladarescu, I., Leeb, H., 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., Mendoza, E., 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., Quesada, J. M., Radeck, D., Ramos-Doval, D., Rauscher, T., Reifarth, R., Rochman, D., Rubbia, C., 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., 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

Background: The $^{14}$N(n,p)$^{14}$C reaction is of interest in neutron capture therapy, where nitrogen-related dose is the main component due to low-energy neutrons, and in astrophysics, where 14N acts as a neutron poison in the s-process. Several discrepancies remain between the existing data obtained in partial energy ranges: thermal energy, keV region and resonance region. Purpose: Measuring the 14N(n,p)14C cross section from thermal to the resonance region in a single measurement for the first time, including characterization of the first resonances, and providing calculations of Maxwellian averaged cross sections (MACS). Method: Time-of-flight technique. Experimental Area 2 (EAR-2) of the neutron time-of-flight (n_TOF) facility at CERN. $^{10}$B(n,${\alpha}$)$^7$Li and $^{235}$U(n,f) reactions as references. Two detection systems running simultaneously, one on-beam and another off-beam. Description of the resonances with the R-matrix code sammy. Results: The cross section has been measured from sub-thermal energy to 800 keV resolving the two first resonances (at 492.7 and 644 keV). A thermal cross-section (1.809$\pm$0.045 b) lower than the two most recent measurements by slightly more than one standard deviation, but in line with the ENDF/B-VIII.0 and JEFF-3.3 evaluations has been obtained. A 1/v energy dependence of the cross section has been confirmed up to tens of keV neutron energy. The low energy tail of the first resonance at 492.7 keV is lower than suggested by evaluated values, while the overall resonance strength agrees with evaluations. Conclusions: Our measurement has allowed to determine the $^{14}$N(n,p) cross-section over a wide energy range for the first time. We have obtained cross-sections with high accuracy (2.5 %) from sub-thermal energy to 800 keV and used these data to calculate the MACS for kT = 5 to kT = 100 keV., Comment: 18 pages, 15 figures, 4 tables

Published
2022
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10. The CERN n TOF NEAR station for astrophysics- and application-related neutron activation measurements

Author

Patronis, N., Mengoni, A., Colonna, N., Cecchetto, M., Domingo-Pardo, C., Aberle, O., Lerendegui-Marco, J., Gervino, G., Stamati, M. E., Goula, S., Bernardes, A. P., Mastromarco, M., Manna, A., Vlastou, R., Massimi, C., Calviani, M., Alcayne, V., Altieri, S., Amaducci, S., Andrzejewski, J., Babiano-Suarez, V., Bacak, M., Balibrea, J., Beltrami, C., Bennett, S., Berthoumieux, E., Boromiza, M., Bosnar, D., Caamano, M., Calvino, F., Cano-Ott, D., Casanovas, A., Cerutti, F., Cescutti, G., Chasapoglou, S., Chiaveri, E., Colombetti, P., Camprini, P. Console, Cortes, G., Cortes-Giraldo, M. A., Cosentino, L., Cristallo, S., Dellmann, S., Di Castro, M., Di Maria, S., Diakaki, M., Dietz, M., Dressler, R., Dupont, E., Duran, I., Eleme, Z., Fargier, S., Fernandez, B., Fernandez-Dominguez, B., Finocchiaro, P., Fiore, S., Furman, V., Garcia-Infantes, F., Gawlik-Ramiega, A., Gilardoni, S., Gonzalez-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., Knapova, I., Kokkoris, M., Kopatch, Y., Krticka, M., Kyritsis, N., Ladarescu, I., Lederer-Woods, C., Lerner, G., Martınez, T., Masi, A., Mastinu, P., Maugeri, E. A., Mazzone, A., Mendoza, E., Milazzo, P. M., Mucciola, R., Murtas, F., Musacchio-Gonzalez, E., Musumarra, A., Negret, A., de Rada, A. Perez, Perez-Maroto, P., Pavon-Rodrıguez, 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., Sanchez, A., Sabate-Gilarte, M., Schillebeeckx, P., Schumann, D., Sekhar, A., Smith, A. G., Sosnin, N. V., Sturniolo, A., Tagliente, G., Tarrio, D., Torres-Sanchez, P., Urlass, S., Vagena, E., Valenta, S., Variale, V., Vaz, P., Vecchio, G., Vescovi, D., Vlachoudis, V., Wallner, T., Woods, P. J., Wright, T., Zarrella, R., and Zugec, P.

Subjects
Physics - Instrumentation and Detectors, Astrophysics - Instrumentation and Methods for Astrophysics, Nuclear Experiment
Abstract

A new experimental area, the NEAR station, has recently been built at the CERN n TOF facility, at a short distance from the spallation target (1.5 m). The new area, characterized by a neutron beam of very high flux, has been designed with the purpose of performing activation measurements of interest for astrophysics and various applications. The beam is transported from the spallation target to the NEAR station through a hole in the shielding wall of the target, inside which a collimator is inserted. The new area is complemented with a {\gamma}-ray spectroscopy laboratory, the GEAR station, equipped with a high efficiency HPGe detector, for the measurement of the activity resulting from irradiation of a sample in the NEAR station. The use of a moderator/filter assembly is envisaged, in order to produce a neutron beam of Maxwellian shape at different thermal energies, necessary for the measurement of Maxwellian Averaged Cross Sections of astrophysical interest. A new fast-cycling activation technique is also being investigated, for measurements of reactions leading to isotopes of very short half life.

Published
2022

11. Advances and new ideas for neutron-capture astrophysics experiments at CERN n_TOF

Author

Domingo-Pardo, C., Babiano-Suarez, V., Balibrea-Correa, J., Caballero, L., Ladarescu, I., Lerendegui-Marco, J., Tain, J. L., Tarifeño-Saldivia, A., Aberle, O., Alcayne, V., Altieri, S., Amaducci, S., Andrzejewski, J., Bacak, M., Beltrami, C., Bennett, S., Bernardes, A. P., Berthoumieux, E., Boromiza, M., Bosnar, D., Caamaño, M., Calviño, F., Calviani, M., Cano-Ott, D., Casanovas, A., Cerutti, F., Cescutti, G., Chasapoglou, S., Chiaveri, E., Chiera, N. M., 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-Ramiega, A., Gervino, G., Gilardoni, S., González-Romero, E., Guerrero, C., Gunsing, F., Gustavino0, C., Heyse, J., Hillman, W., Jenkins, D. G., Jericha, E., Junghans, A., Kadi, Y., Kaperoni, K., Käppeler, F., Kaur, G., Kimura, A., Knapová, I., Koester, U., Kokkoris, M., Kopatch, Y., 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., Milazzo, P. M., Mönch, I., Mucciola, R., Murtas, F., Musacchio-Gonzalez, E., Musumarra, A., Negret, A., de Rada, A. Pérez, 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., Sturniolo, A., Tagliente, G., Tarrío, D., Torres-Sánchez, P., Turko, J., 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
Nuclear Experiment
Abstract

This article presents a few selected developments and future ideas related to the measurement of $(n,\gamma)$ data of astrophysical interest at CERN n_TOF. The MC-aided analysis methodology for the use of low-efficiency radiation detectors in time-of-flight neutron-capture measurements is discussed, with particular emphasis on the systematic accuracy. Several recent instrumental advances are also presented, such as the development of total-energy detectors with $\gamma$-ray imaging capability for background suppression, and the development of an array of small-volume organic scintillators aimed at exploiting the high instantaneous neutron-flux of EAR2. Finally, astrophysics prospects related to the intermediate $i$ neutron-capture process of nucleosynthesis are discussed in the context of the new NEAR activation area., Comment: preprint submitted to the European Physical Journal A, 11 pages, 4 figures

Published
2022
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12. Long-term evolution of the neutron rate at the Canfranc Underground Laboratory

Author

Orrigo, S. E. A., Tain, J. L., Mont-Geli, N., Tarifeño-Saldivia, A., Fraile, L. M., Grieger, M., Agramunt, J., Algora, A., Bemmerer, D., Calviño, F., Cortés, G., De Blas, A., Dillmann, I., Bugarín, A. Domínguez, García, R., Nacher, E., and Tolosa-Delgado, A.

Subjects
Nuclear Experiment, High Energy Physics - Experiment
Abstract

We report results on the long-term variation of the neutron counting rate at the Canfranc Underground Laboratory, of importance for several low-background experiments installed there, including rare-event searches. The measurement campaign was performed employing the High Efficiency Neutron Spectrometry Array (HENSA) mounted in Hall A and lasted 412 live days. The present study is the first long-term measurement of the neutron rate with sensitivity over a wide range of neutron energies (from thermal up to 0.1 GeV and beyond) performed in any underground laboratory so far. Data on the environmental variables inside the experimental hall (radon concentration, air temperature, air pressure and humidity) were also acquired during all the measurement campaign. We have investigated for the first time the evolution of the neutron rate for different energies of the neutrons and its correlation with the ambient variables., Comment: 12 pages, 5 figures, 2 tables

Published
2022
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13. High accuracy, high resolution 235U(n,f) cross section from n_TOF (CERN) in the thermal to 10 keV energy range

Author

collaboration, n_TOF, Mastromarco, M., Amaducci, S., Colonna, N., Finocchiaro, P., Cosentino, L., 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., Damone, L. A., Diakaki, M., Domingo-Pardo, C., Dressler, R., Dupont, E., Durán, I., Fernández-Domínguez, B., Ferrari, A., Ferreira, 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., Meo, S. Lo, Lonsdale, S. J., Macina, D., Manna, A., Marganiec, J., Martínez, T., Masi, A., Massimi, C., Mastinu, P., 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
Nuclear Experiment
Abstract

The 235U(n,f) cross section was measured in a wide energy range (25 meV - 170 keV) at the n_TOF facility at CERN, relative to 6Li(n,t) and 10B(n,alpha) standard reactions, with high resolution and accuracy, with a setup based on a stack of six samples and six silicon detectors placed in the neutron beam. In this paper we report on the results in the region between thermal and 10 keV neutron energy. A resonance analysis has been performed up to 200 eV, with the code SAMMY. The resulting fission kernels are compared with the ones extracted on the basis of the resonance parameters of the most recent major evaluated data libraries. A comparison of the n_TOF data with the evaluated cross sections is also performed from thermal to 10 keV neutron energy for the energy-averaged cross section in energy groups of suitably chosen width. A good agreement is found in average between the new results and the latest evaluated data files ENDF-B/VIII and JEFF-3.3, as well as with respect to the IAEA reference files. However, some discrepancies are still present in some specific energy regions. The new dataset here presented, characterized by unprecedented resolution and accuracy, can help improving the evaluations in the Resolved Resonance Region and up to 10 keV, and reduce the uncertainties that affect this region.

Published
2022

14. First results from the HENSA/ANAIS collaboration at the Canfranc Underground Laboratory

Author

Mont-Geli, N, Tarifeño-Saldivia, A, Orrigo, S E A, Tain, J L, Grieger, M, Agramunt, J, Algora, A, Amaré, J, Bemmerer, D, Calviño, F, Cebrián, S, Coarasa, I, Cortés, G, De Blas, A, Dillmann, I, Fraile, L M, García, E, García, R, Martínez, M, Nacher, E, Ortigoza, Y, Ortiz, A, Pallàs, M, Puimedón, J, Salinas, A, Sarsa, M L, and Tolosa-Delgado, A

Subjects
Nuclear Experiment
Abstract

The HENSA/ANAIS collaboration aims for the precise determination of the neutron flux that could affect ANAIS-112, an experiment looking for the dark matter annual modulation using NaI(Tl) scintillators. In this work, the first measurements of the neutron flux and Monte Carlo simulations of the neutron spectrum are reported.

Published
2021
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15. Measurement of the neutron flux at the Canfranc Underground Laboratory with HENSA

Author

Orrigo, S. E. A., Tain, J. L., Mont-Geli, N., Tarifeño-Saldivia, A., Fraile, L. M., Grieger, M., Agramunt, J., Algora, A., Bemmerer, D., Calviño, F., Cortés, G., De Blas, A., Dillmann, I., Bugarín, A. Domínguez, García, R., Nacher, E., and Tolosa, A.

Subjects
Nuclear Experiment, High Energy Physics - Experiment
Abstract

We have performed a long-term measurement of the neutron flux with the High Efficiency Neutron Spectrometry Array HENSA in the Hall A of the Canfranc Underground Laboratory. The Hall A measurement campaign lasted from October 2019 to March 2021, demonstrating an excellent stability of the HENSA setup. Preliminary results on the neutron flux from this campaign are presented for the first time. In Phase 1 (113 live days) a total neutron flux of 1.66(2) $\times$10$^{-5}$ cm$^{-2}$ s$^{-1}$ is obtained. Our results are in good agreement with those from our previous shorter measurement where a reduced experimental setup was employed., Comment: Proceedings of the 17th International Conference on Topics in Astroparticle and Underground Physics (TAUP 2021)

Published
2021
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16. Imaging neutron capture cross sections: i-TED proof-of-concept and future prospects based on Machine-Learning techniques

Author

Babiano-Suárez, V., Lerendegui-Marco, J., Balibrea-Correa, J., Caballero, L., Calvo, D., Ladarescu, I., Domingo-Pardo, C., Calviño, F., Casanovas, A., Tarifeño-Saldivia, A., Alcayne, V., Guerrero, C., Millán-Callado, M. A., González, M. T. Rodríguez, Barbagallo, M., Aberle, O., Amaducci, S., Andrzejewski, J., Audouin, L., Bacak, 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., Fern\', B., ez-Domínguez, Ferrari, A., Finocchiaro, P., Furman, V., Göbel, K., Garg, R., Gawlik, 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., Knapova, I., Kokkoris, M., Kopatch, Y., Krtička, M., Kurtulgil, D., Lederer-Woods, C., Leeb, H., Lonsdale, S. J., Macina, D., Manna, A., Martinez, 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., 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., 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., Tain, J. L., 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 - Instrumentation and Detectors, Astrophysics - Instrumentation and Methods for Astrophysics, Nuclear Experiment
Abstract

i-TED is an innovative detection system which exploits Compton imaging techniques to achieve a superior signal-to-background ratio in ($n,\gamma$) cross-section measurements using time-of-flight technique. This work presents the first experimental validation of the i-TED apparatus for high-resolution time-of-flight experiments and demonstrates for the first time the concept proposed for background rejection. To this aim both $^{197}$Au($n,\gamma$) and $^{56}$Fe($n, \gamma$) reactions were measured at CERN n\_TOF using an i-TED demonstrator based on only three position-sensitive detectors. Two \cds detectors were also used to benchmark the performance of i-TED. The i-TED prototype built for this study shows a factor of $\sim$3 higher detection sensitivity than state-of-the-art \cds detectors in the $\sim$10~keV neutron energy range of astrophysical interest. This paper explores also the perspectives of further enhancement in performance attainable with the final i-TED array consisting of twenty position-sensitive detectors and new analysis methodologies based on Machine-Learning techniques., Comment: 16 pages, 16 figures

Published
2020
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17. Coronavirus Optimization Algorithm: A bioinspired metaheuristic based on the COVID-19 propagation model

Author

Martínez-Álvarez, F., Asencio-Cortés, G., Torres, J. F., Gutiérrez-Avilés, D., Melgar-García, L., Pérez-Chacón, R., Rubio-Escudero, C., Riquelme, J. C., and Troncoso, A.

Subjects
Computer Science - Artificial Intelligence
Abstract

A novel bioinspired metaheuristic is proposed in this work, simulating how the coronavirus spreads and infects healthy people. From an initial individual (the patient zero), the coronavirus infects new patients at known rates, creating new populations of infected people. Every individual can either die or infect and, afterwards, be sent to the recovered population. Relevant terms such as re-infection probability, super-spreading rate or traveling rate are introduced in the model in order to simulate as accurately as possible the coronavirus activity. The Coronavirus Optimization Algorithm has two major advantages compared to other similar strategies. First, the input parameters are already set according to the disease statistics, preventing researchers from initializing them with arbitrary values. Second, the approach has the ability of ending after several iterations, without setting this value either. Infected population initially grows at an exponential rate but after some iterations, when considering social isolation measures and the high number recovered and dead people, the number of infected people starts decreasing in subsequent iterations. Furthermore, a parallel multi-virus version is proposed in which several coronavirus strains evolve over time and explore wider search space areas in less iterations. Finally, the metaheuristic has been combined with deep learning models, in order to find optimal hyperparameters during the training phase. As application case, the problem of electricity load time series forecasting has been addressed, showing quite remarkable performance., Comment: 30 pages, 4 figures

Published
2020
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18. Review and new concepts for neutron-capture measurements of astrophysical interest

Author

Domingo-Pardo, C., Babiano-Suarez, V., Balibrea-Correa, J., Caballero, L., Ladarescu, I., Lerendegui-Marco, J., Tain, J. L., Calviño, F., Casanovas, A., Segarra, A., Tarifeño-Saldivia, A. E., Guerrero, C., Millán-Callado, M. A., Quesada, J. M., Rodríguez-González, M. T., Aberle, O., Alcayne, V., Amaducci, S., Andrzejewski, J., Audouin, L., Bacak, M., Barbagallo, M., Bennett, S., Berthoumieux, E., Bosnar, D., Brown, A. S., Busso, M., Caamaño, M., Calviani, M., Cano-Ott, D., 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., 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., Gunsing, F., 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., Lederer-Woods, C., 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., 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., 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., 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., Zugec, P. v, and Collaboration, The n_TOF

Subjects
Physics - Instrumentation and Detectors
Abstract

The idea of slow-neutron capture nucleosynthesis formulated in 1957 triggered a tremendous experimental effort in different laboratories worldwide to measure the relevant nuclear physics input quantities, namely ($n,\gamma$) cross sections over the stellar temperature range (from few eV up to several hundred keV) for most of the isotopes involved from Fe up to Bi. A brief historical review focused on total energy detectors will be presented to illustrate how, advances in instrumentation have led, over the years, to the assessment and discovery of many new aspects of $s$-process nucleosynthesis and to the progressive refinement of theoretical models of stellar evolution. A summary will be presented on current efforts to develop new detection concepts, such as the Total-Energy Detector with $\gamma$-ray imaging capability (i-TED). The latter is based on the simultaneous combination of Compton imaging with neutron time-of-flight (TOF) techniques, in order to achieve a superior level of sensitivity and selectivity in the measurement of stellar neutron capture rates., Comment: Nuclear Physics in Astrophysics IX - Conference Proceedings

Published
2019
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19. Measurement of the 235U(n,f) cross section relative to the 6Li(n,t) and 10B(n,alpha) standards from thermal to 170 keV neutron energy range at n_TOF

Author

Amaducci, S., Cosentino, L., Barbagallo, M., Colonna, N., Mengoni, A., Massimi, C., Meo, S. Lo, Finocchiaro, P., Aberle, O., Andrzejewski, J., Audouin, L., Bacak, M., Balibrea, J., 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., Damone, L. A., Diakaki, M., Domingo-Pardo, C., Dressler, R., Dupont, E., Durán, I., Fernández-Domínguez, B., Ferrari, A., Ferreira, 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., Lonsdale, S. J., Macina, D., Manna, A., Marganiec, J., Martínez, T., Masi, A., Mastinu, P., Mastromarco, M., Maugeri, E. A., Mazzone, A., Mendoza, E., 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
Nuclear Experiment, High Energy Physics - Experiment
Abstract

The 235U(n,f) cross section was measured in a wide energy range at n_TOF relative to 6Li(n,t) and 10B(n,alpha), with high resolution and in a wide energy range, with a setup based on a stack of six samples and six silicon detectors placed in the neutron beam. This allowed us to make a direct comparison of the reaction yields under the same experimental conditions, and taking into account the forward/backward emission asymmetry. A hint of an anomaly in the 10{\div}30 keV neutron energy range had been previously observed in other experiments, indicating a cross section systematically lower by several percent relative to major evaluations. The present results indicate that the evaluated cross section in the 9{\div}18 keV neutron energy range is indeed overestimated, both in the recent updates of ENDF/B-VIII.0 and of the IAEA reference data. Furthermore, these new high-resolution data confirm the existence of resonance-like structures in the keV neutron energy region. The new, high accuracy results here reported may lead to a reduction of the uncertainty in the 1{\div}100 keV neutron energy region. Finally, the present data provide additional confidence on the recently re-evaluated cross section integral between 7.8 and 11 eV., Comment: 22 pages, 20 figures, submitted to PRC

Published
2019
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20. Commissioning of the BRIKEN detector for the measurement of very exotic beta-delayed neutron emitters

Author

Tolosa-Delgado, A., Agramunt, J., Tain, J. L., Algora, A., Domingo-Pardo, C., Morales, A. I., Rubio, B., Tarifeno-Saldivia, A., Calvino, F., Cortes, G., Brewer, N. T., Rasco, B. C., Rykaczewski, K. P., Stracener, D. W., Allmond, J. M., Grzywacz, R., Yokoyama, R., Singh, M., King, T., Madurga, M., Nishimura, S., Phong, V. H., Go, S., Liu, J., Matsui, K., Sakurai, H., Kiss, G. G., Isobe, T., Baba, H., Kubono, S., Fukuda, N., Ahn, D. S., Shimizu, Y., Sumikama, T., Suzuki, H., Takeda, H., Soderstrom, P. A., Takechi, M., Bruno, C. G., Davinson, T., Griffin, C. J., Hall, O., Kahl, D., Woods, P. J., Coleman-Smith, P. J., Labiche, M., Lazarus, I., Morrall, P., Pucknell, V. F. E., Simpson, J., Thomas, S. L., Prydderch, M., Harkness-Brennan, L. J., Page, R. D., Dillmann, I., Caballero-Folch, R., Saito, Y., Estrade, A., Nepal, N., Montes, F., Lorusso, G., Liang, J., Bae, S., Ha, J., Moon, B., and collaboration, the BRIKEN

Subjects
Physics - Instrumentation and Detectors
Abstract

A new detection system has been installed at the RIKEN Nishina Center (Japan) to investigate decay properties of very neutron-rich nuclei. The setup consists of three main parts: a moderated neutron counter, a detection system sensitive to the implantation and decay of radioactive ions, and gamma-ray detectors. We describe here the setup, the commissioning experiment and some selected results demonstrating its performance for the measurement of half-lives and beta-delayed neutron emission probabilities. The methodology followed in the analysis of the data is described in detail. Particular emphasis is placed on the correction of the accidental neutron background.

Published
2018
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21. The $^{7}$Be($\boldsymbol{n,p}$)$^{7}$Li reaction and the Cosmological Lithium Problem: measurement of the cross section in a wide energy range at n_TOF (CERN)

Author

Damone, L., Barbagallo, M., Mastromarco, M., Mengoni, A., Cosentino, L., Maugeri, E., Heinitz, S., Schumann, D., Dressler, R., Käppeler, F., Colonna, N., Finocchiaro, P., Andrzejewski, J., Perkowski, J., Gawlik, A., Aberle, O., Altstadt, S., Ayranov, M., Audouin, L., Bacak, M., Balibrea-Correa, J., Ballof, J., Bécares, V., Bečvář, F., Beinrucker, C., Bellia, G., Bernardes, A. P., Berthoumieux, E., Billowes, J., Borge, M. J. G., Bosnar, D., Brown, A., Brugger, M., Busso, M., Caamaño, M., Calviño, F., Calviani, M., Cano-Ott, D., Cardella, R., Casanovas, A., Castelluccio, D. M., Catherall, R., Cerutti, F., Chen, Y. H., Chiaveri, E., Cortés, G., Cortés-Giraldo, M. A., Cristallo, S., Diakaki, M., Dietz, M., Domingo-Pardo, C., Dorsival, A., Dupont, E., Duran, I., Fernandez-Dominguez, B., Ferrari, A., Ferreira, P., Furman, W., Ganesan, S., García-Rio, A., Gilardoni, S., Glodariu, T., Göbel, K., Gonçalves, I. F., González-Romero, E., Goodacre, T. D., Griesmayer, E., Guerrero, C., Gunsing, F., Harada, H., Heftrich, T., Heyse, J., Jenkins, D. G., Jericha, E., Johnston, K., Kadi, Y., Kalamara, A., Katabuchi, T., Kavrigin, P., Kimura, A., Kivel, N., Kohester, U., Kokkoris, M., Krtička, M., Kurtulgil, D., Leal-Cidoncha, E., Lederer-Woods, C., Leeb, H., Lerendegui-Marco, J., Meo, S. Lo, Lonsdale, S. J., Losito, R., Macina, D., Marganiec, J., Marsh, B., Martíne, T., Correia, J. G. Martins, Masi, A., Massimi, C., Mastinu, P., Matteucci, F., Mazzone, A., Mendoza, E., Milazzo, P. M., Mingrone, F., Mirea, M., Musumarra, A., Negret, A., Nolte, R., Oprea, A., Patronis, N., Pavlik, A., Piersanti, L., Piscopo, M., Plompen, A., Porras, I., Praena, J., Quesada, J. M., Radeck, D., Rajeev, K., Rauscher, T., Reifarth, R., Riego-Perez, A., Rothe, S., Rout, P., Rubbia, C., Ryan, J., Sabaté-Gilarte, M., Saxena, A., Schell, J., Schillebeeckx, P., Schmidt, S., Sedyshev, P., Seiffert, C., Smith, A. G., Sosnin, N. V., Stamatopoulos, A., Stora, T., Tagliente, G., Tain, J. L., Tarifeño-Saldivia, A., Tassan-Got, L., Tsinganis, A., Valenta, S., Vannini, G., Variale, V., Vaz, P., Ventura, A., Vlachoudis, V., Vlastou, R., Wallner, A., Warren, S., Weigand, M., Weiß, C., Wolf, C., Woods, P. J., Wright, T., and Žugec, P.

Subjects
Nuclear Experiment
Abstract

We report on the measurement of the $^{7}$Be($n, p$)$^{7}$Li cross section from thermal to approximately 325 keV neutron energy, performed in the high-flux experimental area (EAR2) of the n\_TOF facility at CERN. This reaction plays a key role in the lithium yield of the Big Bang Nucleosynthesis (BBN) for standard cosmology. The only two previous time-of-flight measurements performed on this reaction did not cover the energy window of interest for BBN, and showed a large discrepancy between each other. The measurement was performed with a Si-telescope, and a high-purity sample produced by implantation of a $^{7}$Be ion beam at the ISOLDE facility at CERN. While a significantly higher cross section is found at low-energy, relative to current evaluations, in the region of BBN interest the present results are consistent with the values inferred from the time-reversal $^{7}$Li($p, n$)$^{7}$Be reaction, thus yielding only a relatively minor improvement on the so-called Cosmological Lithium Problem (CLiP). The relevance of these results on the near-threshold neutron production in the p+$^{7}$Li reaction is also discussed.

Published
2018
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22. Cross section measurements of $^{155,157}$Gd(n,$\gamma$) induced by thermal and epithermal neutrons

Author

Mastromarco, M., Manna, A., Aberle, O., Amaducci, S., Andrzejewski, J., Audouin, L., Bacak, M., Balibrea, J., Barbagallo, M., Becvar, F., Berthoumieux, E., Billowes, J., Bosnar, D., Brown, A., Caamano, M., Calvino, F., Calviani, M., Cano-Ott, D., Cardella, R., Casanovas, A., Castelluccio, D. M., Cerutti, F., Chen, Y. H., Chiaveri, E., Clai, G., Colonna, N., Cortes, G., Cortes-Giraldo, M. A., Cosentino, L., Damone, L. A., Diakaki, M., Dietz, M., Domingo-Pardo, C., Dressler, R., Dupont, E., Duran, I., Fernandez-Domnguez, B., Ferrari, A., Ferreira, P., Finocchiaro, P., Furman, V., Gobel, K., Garca, A. R., Gawlik, A., Gilardoni, S., Glodariu, T., Goncalves, I. F., Gonzalez-Romero, E., Griesmayer, E., Guerrero, C., Guglielmelli, A., Gunsing, F., Harada, H., Heinitz, S., Heyse, J., Jenkins, D. G., Jericha, E., Kaeppeler, F., Kadi, Y., Kalamara, A., Kavrigin, P., Kimura, A., Kivel, N., Kokkoris, M., Krticka, M., Kurtulgil, D., Leal-Cidoncha, E., Lederer-Woods, C., Leeb, H., Lerendegui-Marco, J., Lonsdale, S. J., Macina, D., Marganiec, J., Martnez, T., Masi, A., Massimi, C., Mastinu, P., 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., Rocchi, F., Rubbia, C., Ryan, J. A., Sabate-Gilarte, M., Saxena, A., Schillebeeckx, P., Schumann, D., Sedyshev, P., Smith, A. G., Sosnin, N. V., Stamatopoulos, A., Tagliente, G., Tain, J. L., Tarifeno-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 Zugec, P.

Subjects
Nuclear Experiment
Abstract

Neutron capture measurements on $^{155}$Gd and $^{157}$Gd were performed using the time-of-flight technique at the n\_TOF facility at CERN. Four samples in form of self-sustaining metallic discs isotopically enriched in $^{155}$Gd and $^{157}$Gd were used. The measurements were carried out at the experimental area (EAR1) at 185 m from the neutron source, with an array of 4 C$_6$D$_6$ liquid scintillation detectors. The capture cross sections of $^{155}$Gd and $^{157}$Gd at neutron kinetic energy of 0.0253 eV have been estimated to be 62.2(2.2) kb and 239.8(9.3) kb, respectively, thus up to 6\% different relative to the ones reported in the nuclear data libraries. A resonance shape analysis has been performed in the resolved resonance region up to 180 eV and 300 eV, respectively, in average resonance parameters have been found in good agreement with evaluations. Above these energies the observed resonance-like structures in the cross section have been tentatively characterised in terms of resonance energy and area up to 1 keV.

Published
2018
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23. First determination of $\beta$-delayed multiple neutron emission beyond A = 100 through direct neutron measurement: The P$_{2n}$ value of $^{136}$Sb

Author

Caballero-Folch, R., Dillmann, I., Agramunt, J., Taín, J. L., Algora, A., Äystö, J., Calviño, F., Canete, L., Cortès, G., Domingo-Pardo, C., Eronen, T., Ganioglu, E., Gelletly, W., Gorelov, D., Guadilla, V., Hakala, J., Jokinen, A., Kankainen, A., Kolhinen, V., Koponen, J., Marta, M., Mendoza, E., Montaner-Pizá, A., Moore, I., Nobs, C. R., Orrigo, S. E. A., Penttila, H., Pohjalainen, I., Reinikainen, J., Riego, A., Rinta-Antila, S., Rubio, B., Salvador-Castiñeira, P., Simutkin, V., Tarifeño-Saldivia, A., Tolosa-Delgado, A., and Voss, A.

Subjects
Nuclear Experiment
Abstract

Background: $\beta$-delayed multiple neutron emission has been observed for some nuclei with A$\leq$100, with $^{100}$Rb being the heaviest $\beta$2n emitter measured to date. So far, only 25 P$_{2n}$ values have been determined for the $\sim$300 nuclei that may decay in this way. Accordingly, it is of interest to measure P$_{2n}$ values for the other possible multiple neutron emitters throughout the chart of the nuclides. It is of particular interest to make such measurement for nuclei with A$>$100 to test the predictions of theoretical models and simulation tools for the decays of heavy nuclei in the region of very neutron-rich nuclei. In addition, the decay properties of these nuclei are fundamental for the understanding of astrophysical nucleosynthesis processes such as the $r$-process, and safety inputs for nuclear reactors. Purpose: To determine for the first time the two neutron branching ratio, P$_{2n}$ value, for $^{136}$Sb through a direct neutron measurement, and to provide precise P$_{1n}$ values for $^{136}$Sb and $^{136}$Te. Method: Pure beams were provided by the JYFLTRAP at the IGISOL facility of the University of Jyv\"askyl\"a, Finland. The purified ions were implanted into a moving tape at the end of the beam line. The detection setup consisted of a plastic scintillator placed right behind the implantation point, and the BELEN detector, based on neutron counters embedded in a polyethylene matrix. The analysis was based on the study of the $\beta$- and neutron- growth-and-decay curves and the $\beta$-one-neutron and $\beta$-two-neutron time correlations. Results: The P$_{2n}$ value of $^{136}$Sb was found to be 0.14(3)\% and the measured P$_{1n}$ values for $^{136}$Sb and $^{136}$Te were found to be 32.2(15)\% and 1.47(6)\%, respectively. The measured P$_{2n}$ value is a factor 44 smaller than predicted by the FRDM+QRPA model used for $r$-process calculations., Comment: 11 pages, 10 figures

Published
2018
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24. Experimental setup and procedure for the measurement of the 7Be(n,p)7Li reaction at n_TOF

Author

Barbagallo, M., Andrzejewski, J., Mastromarco, M., Perkowski, J., Damone, L. A., Gawlik, A., Cosentino, L., Finocchiaro, P., Maugeri, E. A., Mazzone, A., Dressler, R., Heinitz, S., Kivel, N., Schumann, D., Colonna, N., Aberle, O., Amaducci, S., Audouin, L., Bacak, M., Balibrea, J., Bečvář, F., Bellia, G., 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., Cristallo, S., Diakaki, M., Dietz, M., Domingo-Pardo, C., Dupont, E., Durán, I., Fernández-Domínguez, B., Ferrari, A., Ferreira, P., Furman, V., Göbel, K., García, A. R., Gilardoni, S., Glodariu, T., Gonçalves, I. F., González-Romero, E., Griesmayer, E., Guerrero, C., Gunsing, F., Harada, H., Heyse, J., Jenkins, D. G., Jericha, E., Johnston, K., Käppeler, F., Kadi, Y., Kalamara, A., Kavrigin, P., Kimura, A., Kokkoris, M., Krtička, M., Kurtulgil, D., Lederer, C., Leeb, H., Lerendegui-Marco, J., Meo, S. Lo, Lonsdale, S. J., Macina, D., Manna, A., Marganiec, J., Martínez, T., Martins-Correia, J. G., Masi, A., Massimi, C., Mastinu, P., Mendoza, E., Mengoni, A., Milazzo, P. M., Mingrone, F., Musumarra, A., Negret, A., Nolte, R., Oprea, A., Pappalardo, A. D., Patronis, N., Pavlik, A., Piscopo, M., Porras, I., Praena, J., Quesada, J. M., Radeck, D., Rauscher, T., Reifarth, R., Robles, M. S., Rubbia, C., Ryan, J. A., Sabaté-Gilarte, M., Saxena, A., Schell, J., Schillebeeckx, P., 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 - Instrumentation and Detectors
Abstract

Following the completion of the second neutron beam line and the related experimental area (EAR2) at the n_TOF spallation neutron source at CERN, several experiments were planned and performed. The high instantaneous neutron flux available in EAR2 allows to investigate neutron indiced reactions with charged particles in the exit channel even employing targets made out of small amounts of short-lived radioactive isotopes. After the successful measurement of the 7Be(n,{\alpha}){\alpha} cross section, the 7Be(n,p)7Li reaction was studied in order to provide still missing cross section data of relevance for Big Bang Nucleosynthesis (BBN), in an attempt to find a solution to the cosmological Lithium abundance problem. This paper describes the experimental setup employed in such a measurement and its characterization.

Published
2017
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25. $\beta$-decay half-lives and $\beta$-delayed neutron emission probabilities for several isotopes of Au, Hg, Tl, Pb and Bi, beyond N=126

Author

Caballero-Folch, R., Domingo-Pardo, C., Agramunt, J., Algora, A., Ameil, F., Ayyad, Y., Benlliure, J., Bowry, M., Calviño, F., Cano-Ott, D., Cortès, G., Davinson, T., Dillmann, I., Estrade, A., Evdokimov, A., Faestermann, T., Farinon, F., Galaviz, D., García, A. R., Geissel, H., Gelletly, W., Gernhäuser, R., Gómez-Hornillos, M. B., Guerrero, C., Heil, M., Hinke, C., Knöbel, R., Kojouharov, I., Kurcewicz, J., Kurz, N., Litvinov, Yu. A., Maier, L., Marganiec, J., Marta, M., Martínez, T., Montes, F., Mukha, I., Napoli, D. R., Nociforo, C., Paradela, C., Pietri, S., Podolyák, Zs., Prochazka, A., Rice, S., Riego, A., Rubio, B., Schaffner, H., Scheidenberger, Ch., Smith, K., Sokol, E., Steiger, K., Sun, B., Taín, J. L., Takechi, M., Testov, D., Weick, H., Wilson, E., Winfield, J. S., Wood, R., Woods, P. J., and Yeremin, A.

Subjects
Nuclear Experiment
Abstract

$Background:$ Previous measurements of $\beta$-delayed neutron emitters comprise around 230 nuclei, spanning from the $^{8}$He up to $^{150}$La. Apart from $^{210}$Tl, with a minuscule branching ratio of 0.007\%, no other neutron emitter is measured yet beyond $A=150$. Therefore new data are needed, particularly in the heavy mass region around N=126, in order to guide theoretical models and to understand the formation of the third r-process peak at $A\sim195$. $Purpose:$ To measure both, $\beta$-decay half-lives and neutron branching ratios of several neutron-rich Au, Hg, Tl, Pb and Bi isotopes beyond $N=126$. $Method:$ Ions of interest are produced by fragmentation of a $^{238}$U beam, selected and identified via the GSI-FRS fragment separator. A stack of segmented silicon detectors (SIMBA) is used to measure ion-implants and $\beta$-decays. An array of 30 $^3$He tubes embedded in a polyethylene matrix (BELEN) is used to detect neutrons with high efficiency and selectivity. A self-triggered digital system is employed to acquire data and to enable time-correlations. The latter are analyzed with an analytical model and results for the half-lives and neutron-branching ratios are derived using the binned Maximum-Likelihood method. $Results:$ Twenty new $\beta$-decay half-lives are reported for $^{204-206}$Au, $^{208-211}$Hg,$^{211-216}$Tl,$^{215-218}$Pb and $^{218-220}$Bi, nine of them for the first time. Neutron emission probabilities are reported for $^{210,211}$Hg and $^{211-216}$Tl. $Conclusions:$ The new $\beta$-decay half-lives are in good agreement with previous measurements in this region. The measured neutron emission probabilities are comparable or smaller than values predicted by global models like RHB+RQRPA., Comment: 17 pages, 21 figures, will be submitted at PRC

Published
2017
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26. Neutron capture cross section measurement of 238U at the n TOF CERN facility with C6D6 scintillation detectors in the energy region from 1 eV to 700 keV

Author

Collaboration, n_TOF, Mingrone, F., Massimi, C., Vannini, G., Colonna, N., Gunsing, F., Žugec, P., Altstadt, S., Andrzejewski, J., Audouin, L., Barbagallo, M., Bécares, V., Bečvář, F., Belloni, F., Berthoumieux, E., Billowes, J., Bosnar, D., Brugger, M., Calviani, M., Calviño, F., Cano-Ott, D., Carrapiço, C., Cerutti, F., Chiaveri, E., Chin, M., Cortés, G., Cortés-Giraldo, M. A., Diakaki, M., Domingo-Pardo, C., Duran, I., Dressler, R., Eleftheriadis, C., Ferrari, A., Fraval, K., Ganesan, S., García, A. R., Giubrone, G., Gonçalves, I. F., González-Romero, E., Griesmayer, E., Guerrero, C., Hernández-Prieto, A., Jenkins, D. G., Jericha, E., Kadi, Y., Käppeler, F., Karadimos, D., Kivel, N., Koehler, P., Kokkoris, M., Krtička, 1 M., Kroll, J., Lampoudis, C., Langer, C., Leal-Cidoncha, E., Lederer, C., Leeb, H., Leong, L. S., Meo, S. Lo, Losito, R., Mallick, A., Manousos, A., Marganiec, J., Martínez, T., Mastinu, P. F., Mastromarco, M., Mendoza, E., Mengoni, A., Milazzo, P. M., Mirea, M., Mondalaers, W., Paradela, C., Pavlik, A., Perkowski, J., Plompen, A., Praena, J., Quesada, J. M., Rauscher, T., Reifarth, R., Riego, A., Robles, M. S., Rubbia, C., Sabaté-Gilarte, M., Sarmento, R., Saxena, A., Schillebeeckx, P., Schmidt, S., Schumann, D., Tagliente, G., Tain, J. L., Tarrío, D., Tassan-Got, L., Tsinganis, A., Valenta, S., Variale, V., Vaz, P., Ventura, A., Vermeulen, M. J., Vlachoudis, V., Vlastou, R., Wallner, A., Ware, T., Weigand, M., Weiß, C., and Wright, T.

Subjects
Nuclear Experiment
Abstract

The aim of this work is to provide a precise and accurate measurement of the 238U(n,g) reaction cross section in the energy region from 1 eV to 700 keV. This reaction is of fundamental importance for the design calculations of nuclear reactors, governing the behaviour of the reactor core. In particular, fast reactors, which are experiencing a growing interest for their ability to burn radioactive waste, operate in the high energy region of the neutron spectrum. In this energy region most recent evaluations disagree due to inconsistencies in the existing measurements of up to 15%. In addition, the assessment of nuclear data uncertainty performed for innovative reactor systems shows that the uncertainty in the radiative capture cross-section of 238U should be further reduced to 1-3% in the energy region from 20 eV to 25 keV. To this purpose, addressed by the Nuclear Energy Agency as a priority nuclear data need, complementary experiments, one at the GELINA and two at the n_TOF facility, were proposed and carried out within the 7th Framework Project ANDES of the European Commission. The results of one of these 238U(n,g) measurements performed at the n_TOF CERN facility are presented in this work. The gamma-ray cascade following the radiative neutron capture has been detected exploiting a setup of two C6D6 liquid scintillators. Resonance parameters obtained from this work are on average in excellent agreement with the ones reported in evaluated libraries. In the unresolved resonance region, this work yields a cross section in agreement with evaluated libraries up to 80 keV, while for higher energies our results are significantly higher., Comment: 15 pages, 10 captioned figures

Published
2016
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27. Conceptual design of the BRIKEN detector: A hybrid neutron-gamma detection system for nuclear physics at the RIB facility of RIKEN

Author

Tarifeño-Saldivia, A., Tain, J. L., Domingo-Pardo, C., Calviño, F., Cortes, G., Phong, V. H., Riego, A., and collaboration, The BRIKEN

Subjects
Physics - Instrumentation and Detectors, Nuclear Experiment
Abstract

BRIKEN is a complex detection system to be installed at the RIB-facility of the RIKEN Nishina Center. It is aimed at the detection of heavy-ion implants, $\beta$-particles, $\gamma$-rays and $\beta$-delayed neutrons. The whole detection setup involves the Advanced Implantation Detection Array (AIDA), two HPGe Clover detectors and a large set of 166 counters of 3He embedded in a high-density polyethylene matrix. This article reports on a novel methodology developed for the conceptual design and optimisation of the 3He-tubes array, aiming at the best possible performance in terms of neutron detection. The algorithm is based on a geometric representation of two selected parameters of merit, namely, average neutron detection efficiency and efficiency flatness, as a function of a reduced number of geometric variables. The response of the detection system itself, for each configuration, is obtained from a systematic MC-simulation implemented realistically in Geant4. This approach has been found to be particularly useful. On the one hand, due to the different types and large number of 3He-tubes involved and, on the other hand, due to the additional constraints introduced by the ancillary detectors for charged particles and gamma-rays. Empowered by the robustness of the algorithm, we have been able to design a versatile detection system, which can be easily re-arranged into a compact mode in order to maximize the neutron detection performance, at the cost of the gamma-ray sensitivity. In summary, we have designed a system which shows, for neutron energies up to 1(5) MeV, a rather flat and high average efficiency of 68.6%(64%) and 75.7%(71%) for the hybrid and compact modes, respectively. The performance of the BRIKEN system has been also quantified realistically by means of MC-simulations made with different neutron energy distributions.

Published
2016
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28. Integral measurement of the $^{12}$C(n,p)$^{12}$B reaction up to 10 GeV

Author

Žugec, P., Colonna, N., Bosnar, D., Ventura, A., Mengoni, A., Altstadt, S., Andrzejewski, J., Audouin, L., Barbagallo, M., Bécares, V., Bečvář, F., Belloni, F., Berthoumieux, E., Billowes, J., Boccone, V., Brugger, M., Calviani, M., Calviño, F., Cano-Ott, D., Carrapiço, C., Cerutti, F., Chiaveri, E., Chin, M., Cortés, G., Cortés-Giraldo, M. A., Cosentino, L., Diakaki, M., Domingo-Pardo, C., Dressler, R., Duran, I., Eleftheriadis, C., Ferrari, A., Finocchiaro, P., Fraval, K., Ganesan, S., García, A. R., Giubrone, G., Gómez-Hornillos, M. B., Gonçalves, I. F., González-Romero, E., Griesmayer, E., Guerrero, C., Gunsing, F., Gurusamy, P., Heinitz, S., Jenkins, D. G., Jericha, E., Käppeler, F., Karadimos, D., Kivel, N., Kokkoris, M., Krtička, M., Kroll, J., Langer, C., Lederer, C., Leeb, H., Leong, L. S., Meo, S. Lo, Losito, R., Manousos, A., Marganiec, J., Martínez, T., Massimi, C., Mastinu, P., Mastromarco, M., Mendoza, E., Milazzo, P. M., Mingrone, F., Mirea, M., Mondalaers, W., Musumarra, A., Paradela, C., Pavlik, A., Perkowski, J., Plompen, A., Praena, J., Quesada, J., Rauscher, T., Reifarth, R., Riego, A., Roman, F., Rubbia, C., Sarmento, R., Saxena, A., Schillebeeckx, P., Schmidt, S., Schumann, D., Tagliente, G., Tain, J. L., Tarrío, D., Tassan-Got, L., Tsinganis, A., Valenta, S., Vannini, G., Variale, V., Vaz, P., Versaci, R., Vermeulen, M. J., Vlachoudis, V., Vlastou, R., Wallner, A., Ware, T., Weigand, M., Weiß, C., and Wright, T.

Subjects
Nuclear Experiment
Abstract

The integral measurement of the $^{12}$C(n,p)$^{12}$B reaction was performed at the neutron time of flight facility n_TOF at CERN. The total number of $^{12}$B nuclei produced per neutron pulse of the n_TOF beam was determined using the activation technique in combination with a time of flight technique. The cross section is integrated over the n_TOF neutron energy spectrum from reaction threshold at 13.6 MeV to 10 GeV. Having been measured up to 1 GeV on basis of the $^{235}$U(n,f) reaction, the neutron energy spectrum above 200 MeV has been reevaluated due to the recent extension of the cross section reference for this particular reaction, which is otherwise considered a standard up to 200 MeV. The results from the dedicated GEANT4 simulations have been used to evaluate the neutron flux from 1 GeV up to 10 GeV. The experimental results related to the $^{12}$C(n,p)$^{12}$B reaction are compared with the evaluated cross sections from major libraries and with the predictions of different GEANT4 models, which mostly underestimate the $^{12}$B production. On the contrary, a good reproduction of the integral cross section derived from measurements is obtained with TALYS-1.6 calculations, with optimized parameters., Comment: 14 pages, 11 figures, 3 tables

Published
2016
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29. Experimental setup and procedure for the measurement of the 7Be(n,{\alpha}){\alpha} reaction at n_TOF

Author

Cosentino, L., Musumarra, A., Barbagallo, M., Pappalardo, A., Colonna, N., Damone, L., Piscopo, M., Finocchiaro, P., Maugeri, E., Heinitz, S., Schumann, D., Dressler, R., Kivel, N., Aberle, O., Andrzejewski, J., Audouin, L., Ayranov, M., Bacak, M., Barros, S., Balibrea-Correa, J., Beecares, V., Becvar, F., Beinrucker, C., Berthoumieux, E., Billowes, J., Bosnar, D., Brugger, M., Caamano, M., Calviani, M., Calvino, F., Cano-Ott, D., Cardella, R., Casanovas, A., Castelluccio, D. M., Cerutti, F., Chen, Y. H., Chiaveri, E., Cortes, G., Cortes-Giraldo, M. A., Diakaki, M., Domingo-Pardo, C., Dupont, E., Duran, I., Fernandez-Dominguez, B., Ferrari, A., Ferreira, P., Furman, W., Ganesan, S., Garcia-Rios, A., Gawlik, A., Gheorghe, I., Glodariu, T., Goebel, K., Goncalves, I. F., Gonzalez-Romero, E., Griesmayer, E., Guerrero, C., Gunsing, F., Harada, H., Heftrich, T., Heyse, J., Jenkins, D. G., Jericha, E., Kaeppeler, F., Katabuchi, T., Kavrigin, P., Kimura, A., Kokkoris, M., Krticka, M., Leal-Chidonca, E., Lerendegui, J., Lederer, C., Leeb, H., Meo, S. Lo, Lonsdale, S., Losito, R., Macina, D., Marganiec, J., Martinez, T., Massimi, C., Mastinu, P., Mastromarco, M., Matteucci, F., Mazzone, A., Mendoza, E., Mengoni, A., Milazzo, P. M., Mingrone, F., Mirea, M., Montesano, S., Nolte, R., Oprea, A., Patronis, N., Pavlik, A., Perkowski, J., Praena, J., Quesada, J., Rajeev, K., Rauscher, T., Reifarth, R., Riego-Perez, A., Rout, P., Rubbia, C., Ryan, J., Sabate-Gilarte, M., Saxena, A., Schillebeeckx, P., Schmidt, S., Sedyshev, P., Stamatopoulos, A., Tagliente, G., Tain, J. L., Tarifeno-Saldivia, A., Tassan-Got, L., Tsinganis, A., Valenta, S., Vannini, G., Variale, V., Vaz, P., Ventura, A., Vlachoudis, V., Vlastou, R., Vollaire, J., Wallner, A., Warren, S., Weigand, M., Weiß, C., Wolf, C., Woods, P. J., Wright, T., Zugec, P., and collaboration, n_TOF

Subjects
Physics - Instrumentation and Detectors, High Energy Physics - Experiment, Nuclear Experiment
Abstract

The newly built second experimental area EAR2 of the n_TOF spallation neutron source at CERN allows to perform (n, charged particles) experiments on short-lived highly radioactive targets. This paper describes a detection apparatus and the experimental procedure for the determination of the cross-section of the 7Be(n,{\alpha}) reaction, which represents one of the focal points toward the solution of the cosmological Lithium abundance problem, and whose only measurement, at thermal energy, dates back to 1963. The apparently unsurmountable experimental difficulties stemming from the huge 7Be {\gamma}-activity, along with the lack of a suitable neutron beam facility, had so far prevented further measurements. The detection system is subject to considerable radiation damage, but is capable of disentangling the rare reaction signals from the very high background. This newly developed setup could likely be useful also to study other challenging reactions requiring the detectors to be installed directly in the neutron beam., Comment: submitted to Nuclear Instruments and Methods in Physics Research A

Published
2016
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30. First measurement of several $\beta$-delayed neutron emitting isotopes beyond N=126

Author

Caballero-Folch, R., Domingo-Pardo, C., Agramunt, J., Algora, A., Ameil, F., Arcones, A., Ayyad, Y., Benlliure, J., Borzov, I. N., Bowry, M., Calvino, F., Cano-Ott, D., Cortés, G., Davinson, T., Dillmann, I., Estrade, A., Evdokimov, A., Faestermann, T., Farinon, F., Galaviz, D., García, A. R., Geissel, H., Gelletly, W., Gernhäuser, R., Gómez-Hornillos, M. B., Guerrero, C., Heil, M., Hinke, C., Knöbel, R., Kojouharov, I., Kurcewicz, J., Kurz, N., Litvinov, Y., Maier, L., Marganiec, J., Marketin, T., Marta, M., Martínez, T., Martínez-Pinedo, G., Montes, F., Mukha, I., Napoli, D. R., Nociforo, C., Paradela, C., Pietri, S., Podolyák, Zs., Prochazka, A., Rice, S., Riego, A., Rubio, B., Schaffner, H., Scheidenberger, Ch., Smith, K., Sokol, E., Steiger, K., Sun, B., Taín, J. L., Takechi, M., Testov, D., Weick, H., Wilson, E., Winfield, J. S., Wood, R., Woods, P., and Yeremin, A.

Subjects
Nuclear Experiment, Nuclear Theory
Abstract

The $\beta$-delayed neutron emission probabilities of neutron rich Hg and Tl nuclei have been measured together with $\beta$-decay half-lives for 20 isotopes of Au, Hg, Tl, Pb and Bi in the mass region N$\gtrsim$126. These are the heaviest species where neutron emission has been observed so far. These measurements provide key information to evaluate the performance of nuclear microscopic and phenomenological models in reproducing the high-energy part of the $\beta$-decay strength distribution. In doing so, it provides important constraints to global theoretical models currently used in $r$-process nucleosynthesis., Comment: Submitted to Phys. Rev. Lett

Published
2015
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31. Measurement and analysis of the Am-243 neutron capture cross section at the n_TOF facility at CERN

Author

Collaboration, n_TOF, Mendoza, E., Cano-Ott, D., Guerrero, C., Berthoumieux, E., Abbondanno, U., Aerts, G., Alvarez-Velarde, F., Andriamonje, S., Andrzejewski, J., Assimakopoulos, P., Audouin, L., Badurek, G., Balibrea, J., Baumann, P., Becvar, F., Belloni, F., Calvino, F., Calviani, M., Capote, R., Carrapico, C., de Albornoz, A. Carrillo, Cennini, P., Chepel, V., Chiaveri, E., Colonna, N., Cortes, G., Couture, A., Cox, J., Dahlfors, M., David, S., Dillmann, I., Dolfini, R., Domingo-Pardo, C., Dridi, W., Duran, I., Eleftheriadis, C., Ferrant, L., Ferrari, A., Ferreira-Marques, R., Fitzpatrick, L., Frais-Koelbl, H., Fujii, K., Furman, W., Goncalves, I., Gonzalez-Romero, E., Goverdovski, A., Gramegna, F., Griesmayer, E., Gunsing, F., Haas, B., Haight, R., Heil, M., Herrera-Martinez, A., Igashira, M., Isaev, S., Jericha, E., Kappeler, F., Kadi, Y., Karadimos, D., Karamanis, D., Ketlerov, V., Kerveno, M., Koehler, P., Konovalov, V., Kossionides, E., Krticka, M., Lampoudis, C., Leeb, H., Lindote, A., Lopes, I., Lossito, R., Lozano, M., Lukic, S., Marganiec, J., Marques, L., Marrone, S., Martinez, T., Massimi, C., Mastinu, P., Mengoni, A., Milazzo, P. M., Moreau, C., Mosconi, M., Neves, F., Oberhummer, H., Brien, S. O, Oshima, M., Pancin, J., Papachristodoulou, C., Papadopoulos, C., Paradela, C., Patronis, N., Pavlik, A., Pavlopoulos, P., Perrot, L., Pigni, M. T., Plag, R., Plompen, A., Plukis, A., Poch, A., Praena, J., Pretel, C., Quesada, J., Rauscher, T., Reifarth, R., Rosetti, M., Rubbia, C., Rudolf, G., Rullhusen, P., Salgado, J., Santos, C., Sarchiapone, L., Savvidis, I., Stephan, C., Tagliente, G., Tain, J. L., Tassan-Got, L., Tavora, L., Terlizzi, R., Vannini, G., Vaz, P., Ventura, A., Villamarin, D., Vicente, M. C., Vlachoudis, V., Vlastou, R., Voss, F., Walter, S., Wendler, H., Wiescher, M., and Wisshak, K.

Subjects
Nuclear Experiment
Abstract

Background:The design of new nuclear reactors and transmutation devices requires to reduce the present neutron cross section uncertainties of minor actinides. Purpose: Reduce the $^{243}$Am(n,$\gamma$) cross section uncertainty. Method: The $^{243}$Am(n,$\gamma$) cross section has been measured at the n_TOF facility at CERN with a BaF$_{2}$ Total Absorption Calorimeter, in the energy range between 0.7 eV and 2.5 keV. Results: The $^{243}$Am(n,$\gamma$) cross section has been successfully measured in the mentioned energy range. The resolved resonance region has been extended from 250 eV up to 400 eV. In the unresolved resonance region our results are compatible with one of the two incompatible capture data sets available below 2.5 keV. The data available in EXFOR and in the literature has been used to perform a simple analysis above 2.5 keV. Conclusions: The results of this measurement contribute to reduce the $^{243}$Am(n,$\gamma$) cross section uncertainty and suggest that this cross section is underestimated up to 25% in the neutron energy range between 50 eV and a few keV in the present evaluated data libraries.

Published
2014
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32. High accuracy determination of the $^{238}$U/$^{235}$U fission cross section ratio up to $\sim$1 GeV at n_TOF (CERN)

Author

Paradela, C., Calviani, M., Tarrío, D., Leal-Cidoncha, E., Leong, L. S., Tassan-Got, L., Naour, C. Le, Duran, I., Colonna, N., Audouin, L., Mastromarco, M., Meo, S. Lo, Ventura, A., Altstadt, S., Andrzejewski, J., Barbagallo, M., Bécares, V., Bečvář, F., Belloni, F., Berthoumieux, E., Billowes, J., Boccone, V., Bosnar, D., Brugger, M., Calviño, F., Cano-Ott, D., Carrapiço, C., Cerutti, F., Chiaveri, E., Chin, M., Cortés, G., Cortés-Giraldo, M. A., Cosentino, L., Diakaki, M., Domingo-Pardo, C., Dressler, R., Eleftheriadis, C., Ferrari, A., Finocchiaro, P., Fraval, K., Ganesan, S., García, A. R., Giubrone, G., Gómez-Hornillos, M. B., Gonçalves, I. F., González-Romero, E., Griesmayer, E., Guerrero, C., Gunsing, F., Gurusamy, P., Heinitz, S., Jenkins, D. G., Jericha, E., Käppeler, F., Karadimos, D., Kivel, N., Kokkoris, M., Krtička, M., Kroll, J., Langer, C., Lederer, C., Leeb, H., Losito, R., Manousos, A., Marganiec, J., Martínez, T., Massimi, C., Mastinu, P., Mendoza, E., Mengoni, A., Milazzo, P. M., Mingrone, F., Mirea, M., Mondalaers, W., Musumarra, A., Pavlik, A., Perkowski, J., Plompen, A., Praena, J., Quesada, J., Rauscher, T., Reifarth, R., Riego, A., Roman, F., Rubbia, C., Sarmento, R., Saxena, A., Schillebeeckx, P., Schmidt, S., Schumann, D., Tagliente, G., Tain, J. L., Tsinganis, A., Valenta, S., Vannini, G., Variale, V., Vaz, P., Versaci, R., Vermeulen, M. J., Vlachoudis, V., Vlastou, R., Wallner, A., Ware, T., Weigand, M., Weiß, C., Wright, T., and Žugec, P.

Subjects
Nuclear Experiment
Abstract

The $^{238}$U to $^{235}$U fission cross section ratio has been determined at n_TOF up to $\sim$1 GeV, with two different detection systems, in different geometrical configurations. A total of four datasets have been collected and compared. They are all consistent to each other within the relative systematic uncertainty of 3-4%. The data collected at n_TOF have been suitably combined to yield a unique fission cross section ratio as a function of the neutron energy. The result confirms current evaluations up to 200 MeV. A good agreement is also observed with theoretical calculations based on the INCL++/Gemini++ combination up to the highest measured energy. The n_TOF results may help solving a long-standing discrepancy between the two most important experimental dataset available so far above 20 MeV, while extending the neutron energy range for the first time up to $\sim$1 GeV.

Published
2014
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33. Measurement of the $^{12}$C($n,p$)$^{12}$B cross section at n_TOF (CERN) by in-beam activation analysis

Author

Žugec, P., Colonna, N., Bosnar, D., Mengoni, A., Altstadt, S., Andrzejewski, J., Audouin, L., Barbagallo, M., Bécares, V., Bečvář, F., Belloni, F., Berthoumieux, E., Billowes, J., Boccone, V., Brugger, M., Calviani, M., Cano-Ott, F. Calviño D., Carrapiço, C., Cerutti, F., Chiaveri, E., Chin, M., Cortés, G., Cortés-Giraldo, M. A., Cosentino, L., Diakaki, M., Domingo-Pardo, C., Dressler, R., Duran, I., Eleftheriadis, C., Ferrari, A., Finocchiaro, P., Fraval, K., Ganesan, S., García, A. R., Giubrone, G., Gómez-Hornillos, M. B., Gonçalves, I. F., González-Romero, E., Griesmayer, E., Guerrero, C., Gunsing, F., Gurusamy, P., Heinitz, S., Jenkins, D. G., Jericha, E., Käppeler, F., Karadimos, D., Kivel, N., Kokkoris, M., Krtička, M., Kroll, J., Langer, C., Lederer, C., Leeb, H., Leong, L. S., LoMeo, S., Losito, R., Manousos, A., Marganiec, J., Martínez, T., Massimi, C., Mastinu, P., Mastromarco, M., Mendoza, E., Milazzo, P. M., Mingrone, F., Mirea, M., Mondalaers, W., Musumarra, A., Paradela, C., Pavlik, A., Perkowski, J., Plompen, A., Praena, J., Quesada, J., Rauscher, T., Reifarth, R., Riego, A., Roman, F., Rubbia, C., Sarmento, R., Saxena, A., Schillebeeckx, P., Schmidt, S., Schumann, D., Tagliente, G., Tain, J. L., Tarrío, D., Tassan-Got, L., Tsinganis, A., Valenta, S., Vannini, G., Variale, V., Vaz, P., Ventura, A., Versaci, R., Vermeulen, M. J., Vlachoudis, V., Vlastou, R., Wallner, A., Ware, T., Weigand, M., Weiß, C., and Wright, T.

Subjects
Nuclear Experiment
Abstract

The integral cross section of the $^{12}$C($n,p$)$^{12}$B reaction has been determined for the first time in the neutron energy range from threshold to several GeV at the n_TOF facility at CERN. The measurement relies on the activation technique, with the $\beta$-decay of $^{12}$B measured over a period of four half-lives within the same neutron bunch in which the reaction occurs. The results indicate that model predictions, used in a variety of applications, are mostly inadequate. The value of the integral cross section reported here can be used as a benchmark for verifying or tuning model calculations., Comment: 6 pages, 4 figures

Published
2014
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34. GEANT4 simulation of the neutron background of the C$_6$D$_6$ set-up for capture studies at n_TOF

Author

collaboration, n_TOF, Žugec, P., Colonna, N., Bosnar, D., Altstadt, S., Andrzejewski, J., Audouin, L., Barbagallo, M., Bécares, V., Bečvář, F., Belloni, F., Berthoumieux, E., Billowes, J., Boccone, V., Brugger, M., Calviani, M., Calviño, F., Cano-Ott, D., Carrapiço, C., Cerutti, F., Chiaveri, E., Chin, M., Cortés, G., Cortés-Giraldo, M. A., Diakaki, M., Domingo-Pardo, C., Dressler, R., Duran, I., Dzysiuk, N., Eleftheriadis, C., Ferrari, A., Fraval, K., Ganesan, S., García, A. R., Giubrone, G., Gómez-Hornillos, M. B., Gonçalves, I. F., González-Romero, E., Griesmayer, E., Guerrero, C., Gunsing, F., Gurusamy, P., Heinitz, S., Jenkins, D. G., Jericha, E., Kadi, Y., Käppeler, F., Karadimos, D., Kivel, N., Koehler, P., Kokkoris, M., Krtička, M., Kroll, J., Langer, C., Lederer, C., Leeb, H., Leong, L. S., Meo, S. Lo, Losito, R., Manousos, A., Marganiec, J., Martìnez, T., Massimi, C., Mastinu, P. F., Mastromarco, M., Meaze, M., Mendoza, E., Mengoni, A., Milazzo, P. M., Mingrone, F., Mirea, M., Mondalaers, W., Paradela, C., Pavlik, A., Perkowski, J., Plompen, A., Praena, J., Quesada, J. M., Rauscher, T., Reifarth, R., Riego, A., Roman, F., Rubbia, C., Sarmento, R., Saxena, A., Schillebeeckx, P., Schmidt, S., Schumann, D., Tagliente, G., Tain, J. L., Tarrío, D., Tassan-Got, L., Tsinganis, A., Valenta, S., Vannini, G., Variale, V., Vaz, P., Ventura, A., Versaci, R., Vermeulen, M. J., Vlachoudis, V., Vlastou, R., Wallner, A., Ware, T., Weigand, M., Weiß, C., and Wright, T.

Subjects
Physics - Instrumentation and Detectors, Nuclear Experiment
Abstract

The neutron sensitivity of the C$_6$D$_6$ detector setup used at n_TOF for capture measurements has been studied by means of detailed GEANT4 simulations. A realistic software replica of the entire n_TOF experimental hall, including the neutron beam line, sample, detector supports and the walls of the experimental area has been implemented in the simulations. The simulations have been analyzed in the same manner as experimental data, in particular by applying the Pulse Height Weighting Technique. The simulations have been validated against a measurement of the neutron background performed with a $^\mathrm{nat}$C sample, showing an excellent agreement above 1 keV. At lower energies, an additional component in the measured $^\mathrm{nat}$C yield has been discovered, which prevents the use of $^\mathrm{nat}$C data for neutron background estimates at neutron energies below a few hundred eV. The origin and time structure of the neutron background have been derived from the simulations. Examples of the neutron background for two different samples are demonstrating the important role of accurate simulations of the neutron background in capture cross section measurements.

Published
2014
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35. $^{62}$Ni($n,\gamma$) and $^{63}$Ni($n,\gamma$) cross sections measured at n_TOF/CERN

Author

Lederer, C., Massimi, C., Berthoumieux, E., Colonna, N., Dressler, R., Guerrero, C., Gunsing, F., Käppeler, F., Kivel, N., Pignatari, M., Reifarth, R., Schumann, D., Wallner, A., Altstadt, S., Andriamonje, S., Andrzejewski, J., Audouin, L., Barbagallo, M., Becares, V., Becvar, F., Belloni, F., Berthier, B., Billowes, J., Boccone, V., Bosnar, D., Brugger, M., Calviani, M., Calvino, F., Cano-Ott, D., Carrapico, C., Cerutti, F., Chiaveri, E., Chin, M., Cortes, G., Cortes-Giraldo, M. A., Dillmann, I., Domingo-Pardo, C., Duran, I., Dzysiuk, N., Eleftheriadis, C., Fernandez-Ordonez, M., Ferrari, A., Fraval, K., Ganesan, S., Garcıa, A. R., Giubrone, G., Gomez-Hornillos, M. B., Goncalves, I. F., Gonzalez-Romero, E., Gramegna, F., Griesmayer, E., Gurusamy, P., Harrisopulos, S., Heil, M., Ioannides, K., Jenkins, D. G., Jericha, E., Kadi, Y., Karadimos, D., Korschinek, G., Krticka, M., Kroll, J., Langer, C., Lebbos, E., Leeb, H., Leong, L. S., Losito, R., Lozano, M., Manousos, A., Marganiec, J., Marrone, S., Martinez, T., Mastinu, P. F., Mastromarco, M., Meaze, M., Mendoza, E., Mengoni, A., Milazzo, P. M., Mingrone, F., Mirea, M., Mondalaers, W., Paradela, C., Pavlik, A., Perkowski, J., Plag, R., Plompen, A., Praena, J., Quesada, J. M., Rauscher, T., Riego, A., Roman, F., Rubbia, C., Sarmento, R., Schillebeeckx, P., Schmidt, S., Tagliente, G., Tain, J. L., Tarrıo, D., Tassan-Got, L., Tsinganis, A., Tlustos, L., Valenta, S., Vannini, G., Variale, V., Vaz, P., Ventura, A., Vermeulen, M. J., Versaci, R., Vlachoudis, V., Vlastou, R., Ware, T., Weigand, M., Weiß, C., Wright, T. J., and Zugec, P.

Subjects
Nuclear Experiment
Abstract

The cross section of the $^{62}$Ni($n,\gamma$) reaction was measured with the time-of-flight technique at the neutron time-of-flight facility n_TOF at CERN. Capture kernels of 42 resonances were analyzed up to 200~keV neutron energy and Maxwellian averaged cross sections (MACS) from $kT=5-100$ keV were calculated. With a total uncertainty of 4.5%, the stellar cross section is in excellent agreement with the the KADoNiS compilation at $kT=30$ keV, while being systematically lower up to a factor of 1.6 at higher stellar temperatures. The cross section of the $^{63}$Ni($n,\gamma$) reaction was measured for the first time at n_TOF. We determined unresolved cross sections from 10 to 270 keV with a systematic uncertainty of 17%. These results provide fundamental constraints on $s$-process production of heavier species, especially the production of Cu in massive stars, which serve as the dominant source of Cu in the solar system.

Published
2014
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36. Experimental neutron capture data of $^{58}$Ni from the CERN n_TOF facility

Author

collaboration, n_TOF, Žugec, P., Barbagallo, M., Colonna, N., Bosnar, D., Altstadt, S., Andrzejewski, J., Audouin, L., Bécares, V., Bečvář, F., Belloni, F., Berthoumieux, E., Billowes, J., Boccone, V., Brugger, M., Calviani, M., Calviño, F., Cano-Ott, D., Carrapiço, C., Cerutti, F., Chiaveri, E., Chin, M., Cortés, G., Cortés-Giraldo, M. A., Diakaki, M., Domingo-Pardo, C., Duran, I., Dzysiuk, N., Eleftheriadis, C., Ferrari, A., Fraval, K., Ganesan, S., García, A. R., Giubrone, G., Gómez-Hornillos, M. B., Gonçalves, I. F., González-Romero, E., Griesmayer, E., Guerrero, C., Gunsing, F., Gurusamy, P., Jenkins, D. G., Jericha, E., Kadi, Y., Käppeler, F., Karadimos, D., Koehler, P., Kokkoris, M., Krtička, M., Kroll, J., Langer, C., Lederer, C., Leeb, H., Leong, L. S., Losito, R., Manousos, A., Marganiec, J., Martìnez, T., Massimi, C., Mastinu, P. F., Mastromarco, M., Meaze, M., Mendoza, E., Mengoni, A., Milazzo, P. M., Mingrone, F., Mirea, M., Mondalaers, W., Paradela, C., Pavlik, A., Perkowski, J., Pignatari, M., Plompen, A., Praena, J., Quesada, J. M., Rauscher, T., Reifarth, R., Riego, A., Roman, F., Rubbia, C., Sarmento, R., Schillebeeckx, P., Schmidt, S., Tagliente, G., Tain, J. L., Tarrío, D., Tassan-Got, L., Tsinganis, A., Valenta, S., Vannini, G., Variale, V., Vaz, P., Ventura, A., Versaci, R., Vermeulen, M. J., Vlachoudis, V., Vlastou, R., Wallner, A., Ware, T., Weigand, M., Weiß, C., and Wright, T.

Subjects
Nuclear Experiment
Abstract

The $^{58}$Ni $(n,\gamma)$ cross section has been measured at the neutron time of flight facility n_TOF at CERN, in the energy range from 27 meV up to 400 keV. In total, 51 resonances have been analyzed up to 122 keV. Maxwellian averaged cross sections (MACS) have been calculated for stellar temperatures of kT$=$5-100 keV with uncertainties of less than 6%, showing fair agreement with recent experimental and evaluated data up to kT = 50 keV. The MACS extracted in the present work at 30 keV is 34.2$\pm$0.6$_\mathrm{stat}\pm$1.8$_\mathrm{sys}$ mb, in agreement with latest results and evaluations, but 12% lower relative to the recent KADoNIS compilation of astrophysical cross sections. When included in models of the s-process nucleosynthesis in massive stars, this change results in a 60% increase of the abundance of $^{58}$Ni, with a negligible propagation on heavier isotopes. The reason is that, using both the old or the new MACS, 58Ni is efficiently depleted by neutron captures., Comment: 10 pages, 8 figures, 5 tables

Published
2014
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37. Characterization and First Test of an i-TED Prototype at CERN n_TOF

Author

Babiano-Suarez, V., Caballero, L., Domingo-Pardo, C., Ladarescu, I., Aberle, O., Alcayne, V., Amaducci, S., Andrzejewski, J., Audouin, L., Bacak, M., Barbagallo, M., Bécares, V., Bečvář, F., Bellia, G., Berthoumieux, E., Billowes, J., Bosnar, D., Brown, A. S., Busso, M., Caamaño, M., Calviani, M., Calviño, F., Cano-Ott, D., 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., Dressler, R., Dupont, E., Durán, I., Eleme, Z., Fernández-Domíngez, B., Ferrari, A., Ferro-Gon calves, I., Finocchiaro, P., Furman, V., Gawlik, A., Gilardoni, S., Glodariu, T., Göbel, K., González-Romero, E., Guerrero, C., Gunsing, F., Heinitz, S., Heyse, J., Jenkins, D. G., Kadi, Y., Käppeler, F., Kimura, A., Kivel, N., Kokkoris, M., Kopatch, Y., Krtička, M., Kurtulgil, D., 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., Mendoza, E., 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., Rausher, T., 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., 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., Žugec, P., García-Ramos, José-Enrique, editor, Andrés, María V., editor, Valera, José A. Lay, editor, Moro, Antonio M., editor, and Pérez-Bernal, Francisco, editor

Published
2019
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38. Measurement of the Cm Neutron-Induced Cross Sections at the n_TOF Facility

Author

Alcayne, V., Kimura, A., Mendoza, E., Cano-Ott, D., 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-Gon calves, I., Finocchiaro, P., Furman, V., Gawlik, A., Gilardoni, S., Glodariu, T., Göbel, K., González-Romero, E., Guerrero, C., Gunsing, F., Heinitz, S., Heyse, J., Jenkins, D. G., 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, Rausher, T., 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., 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., Žugec, P., García-Ramos, José-Enrique, editor, Andrés, María V., editor, Valera, José A. Lay, editor, Moro, Antonio M., editor, and Pérez-Bernal, Francisco, editor

Published
2019
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39. Approaching the precursor nuclei of the third r-process peak with RIBs

Author

Domingo-Pardo, C., Caballero-Folch, R., Agramunt, J., Algora, A., Arcones, A., Ameil, F., Ayyad, Y., Benlliure, J., Bowry, M., Calviño, F., Cano-Ott, D., Cortés, G., Davinson, T., Dillmann, I., Estrade, A., Evdokimov, A., Faestermann, T., Farinon, F., Galaviz, D., García-Rios, A., Geissel, H., Gelletly, W., Gernhäuser, R., Gómez-Hornillos, M. B., Guerrero, C., Heil, M., Hinke, C., Knöbel, R., Kojouharov, I., Kurcewicz, J., Kurz, N., Litvinov, Y., Maier, L., Marganiec, J., Marta, M., Martínez, T., Martínez-Pinedo, G., Meyer, B. S., Montes, F., Mukha, I., Napoli, D. R., Nociforo, Ch., Paradela, C., Pietri, S., Podolyák, Z., Prochazka, A., Rice, S., Riego, A., Rubio, B., Schaffner, H., Scheidenberger, Ch., Smith, K., Sokol, E., Steiger, K., Sun, B., Taín, J. L., Takechi, M., Testov, D., Weick, H., Wilson, E., Winfield, J. S., Wood, R., Woods, P., and Yeremin, A.

Subjects
Nuclear Experiment
Abstract

The rapid neutron nucleosynthesis process involves an enormous amount of very exotic neutron-rich nuclei, which represent a theoretical and experimental challenge. Two of the main decay properties that affect the final abundance distribution the most are half-lives and neutron branching ratios. Using fragmentation of a primary $^{238}$U beam at GSI we were able to measure such properties for several neutron-rich nuclei from $^{208}$Hg to $^{218}$Pb. This contribution provides a short update on the status of the data analysis of this experiment, together with a compilation of the latest results published in this mass region, both experimental and theoretical. The impact of the uncertainties connected with the beta-decay rates and with beta-delayed neutron emission is illustrated on the basis of $r$-process network calculations. In order to obtain a reasonable reproduction of the third $r$-process peak, it is expected that both half-lives and neutron branching ratios are substantially smaller, than those based on FRDM+QRPA, commonly used in $r$-process model calculations. Further measurements around $N\sim126$ are required for a reliable modelling of the underlying nuclear structure, and for performing more realistic $r$-process abundance calculations., Comment: Nuclear Physics in Astrophysics VI, Lisbon 2013, Conference Proceedings

Published
2013

40. Neutron capture cross section of unstable 63Ni: implications for stellar nucleosynthesis

Author

Lederer, C., Massimi, C., Altstadt, S., Andrzejewski, J., Audouin, L., Barbagallo, M., Bécares, V., Bevá, F., Belloni, F., Berthoumieux, E., Billowes, J., Boccone, V., Bosnar, D., Brugger, M., Calviani, M., Calviño, F., Cano-Ott, D., Carrapiço, C., Cerutti, F., Chiaveri, E., Chin, M., Colonna, N., Cortés, G., Cortés-Giraldo, M. A., Diakaki, M., Domingo-Pardo, C., Duran, I., Dressler, R., Dzysiuk, N., Eleftheriadis, C., Ferrari, A., Fraval, K., Ganesan, S., García, A. R., Giubrone, G., Gómez-Hornillos, M. B., Gonçalves, I. F., González-Romero, E., Griesmayer, E., Guerrero, C., Gunsing, F., Gurusamy, P., Jenkins, D. G., Jericha, E., Kadi, Y., Käppeler, F., Karadimos, D., Kivel, N., Koehler, P., Kokkoris, M., Korschinek, G., Krtika, M., Kroll, J., Langer, C., Leeb, H., Leong, L. S., Losito, R., Manousos, A., Marganiec, J., Martínez, T., Mastinu, P. F., Mastromarco, M., Meaze, M., Mendoza, E., Mengoni, A., Milazzo, P. M., Mingrone, F., Mirea, M., Mondelaers, W., Paradela, C., Pavlik, A., Perkowski, J., Pignatari, M., Plompen, A., Praena, J., Quesada, J. M., Rauscher, T., Reifarth, R., Riego, A., Roman, F., Rubbia, C., Sarmento, R., Schillebeeckx, P., Schmidt, S., Schumann, D., Tagliente, G., Tain, J. L., Tarrío, D., Tassan-Got, L., Tsinganis, A., Valenta, S., Vannini, G., Variale, V., Vaz, P., Ventura, A., Versaci, R., Vermeulen, M. J., Vlachoudis, V., Vlastou, R., Wallner, A., Ware, T., Weigand, M., Weiß, C., Wright, T. J., and Zugec, P.

Subjects
Nuclear Experiment, Astrophysics - Solar and Stellar Astrophysics
Abstract

The $^{63}$Ni($n, \gamma$) cross section has been measured for the first time at the neutron time-of-flight facility n\_TOF at CERN from thermal neutron energies up to 200 keV. In total, capture kernels of 12 (new) resonances were determined. Maxwellian Averaged Cross Sections were calculated for thermal energies from kT = 5 keV to 100 keV with uncertainties around 20%. Stellar model calculations for a 25 M$_\odot$ star show that the new data have a significant effect on the $s$-process production of $^{63}$Cu, $^{64}$Ni, and $^{64}$Zn in massive stars, allowing stronger constraints on the Cu yields from explosive nucleosynthesis in the subsequent supernova.

Published
2013
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42. Measurement of the neutron-induced fission cross-section of 241Am at the time-of-flight facility n_TOF

Author

Belloni, F., Calviani, M., Colonna, N., Mastinu, P., Milazzo, P. M., Abbondanno, U., Aerts, G., Álvarez, H., Alvarez-Velarde, F., Andriamonje, S., Andrzejewski, J., Audouin, L., Badurek, G., Barbagallo, M., Baumann, P., Bečvář, F., Berthoumieux, E., Calviño, F., Cano-Ott, D., Capote, R., Carrapiço, C., Cennini, P., Chepel, V., Chiaveri, E., Cortes, G., Couture, A., Cox, J., Dahlfors, M., David, S., Dillmann, I., Domingo-Pardo, C., Dridi, W., Duran, I., Eleftheriadis, C., Embid-Segura, M., Ferrari, A., Ferreira-Marques, R., Fujii, K., Furman, W., Goncalves, I., Gonzalez-Romero, E., Goverdovski, A., Gramegna, F., Guerrero, C., Gunsing, F., Haas, B., Haight, R., Heil, M., Herrera-Martinez, A., Igashira, M., Jericha, E., Käppeler, F., Kadi, Y., Karadimos, D., Karamanis, D., Kerveno, M., Koehler, P., Kossionides, E., Krtička, M., Lamboudis, C., Leeb, H., Lindote, A., Lopes, I., Lozano, M., Lukic, S., Marganiec, J., Marrone, S., Martínez, T., Massimi, C., Meaze, M. H., Mengoni, A., Moreau, C., Mosconi, M., Neves, F., Oberhummer, H., O’Brien, S., Papachristodoulou, C., Papadopoulos, C., Paradela, C., Patronis, N., Pavlik, A., Pavlopoulos, P., Perrot, L., Pigni, M. T., Plag, R., Plompen, A., Plukis, A., Poch, A., Praena, J., Pretel, C., Quesada, J., Rauscher, T., Reifarth, R., Rosetti, M., Rubbia, C., Rudolf, G., Rullhusen, P., Salgado, J., Santos, C., Sarchiapone, L., Savvidis, I., Stephan, C., Tagliente, G., Tain, J. L., Tarrio, D., Tassan-Got, L., Tavora, L., Terlizzi, R., Vannini, G., Vaz, P., Ventura, A., Villamarin, D., Vincente, M. C., Vlachoudis, V., Vlastou, R., Voss, F., Walter, S., Wiescher, M., and Wisshak, K.

Published
2013
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43. Measurement of the neutron-induced fission cross-section of 243Am relative to 235U from 0.5 to 20 MeV

Author

Belloni, F., Calviani, M., Colonna, N., Mastinu, P., Milazzo, P. M., Abbondanno, U., Aerts, G., Álvarez, H., Alvarez-Velarde, F., Andriamonje, S., Andrzejewski, J., Audouin, L., Badurek, G., Barbagallo, M., Baumann, P., Bečvář, F., Berthoumieux, E., Calviño, F., Cano-Ott, D., Capote, R., Carrapiço, C., Cennini, P., Chepel, V., Chiaveri, E., Cortes, G., Couture, A., Cox, J., Dahlfors, M., David, S., Dillmann, I., Domingo-Pardo, C., Dridi, W., Duran, I., Eleftheriadis, C., Embid-Segura, M., Ferrari, A., Ferreira-Marques, R., Fujii, K., Furman, W., Goncalves, I., Gonzalez-Romero, E., Goverdovski, A., Gramegna, F., Guerrero, C., Gunsing, F., Haas, B., Haight, R., Heil, M., Herrera-Martinez, A., Igashira, M., Jericha, E., Käppeler, F., Kadi, Y., Karadimos, D., Karamanis, D., Kerveno, M., Koehler, P., Kossionides, E., Krtička, M., Lamboudis, C., Leeb, H., Lindote, A., Lopes, I., Lozano, M., Lukic, S., Marganiec, J., Marrone, S., Martínez, T., Massimi, C., Meaze, M. H., Mengoni, A., Moreau, C., Mosconi, M., Neves, F., Oberhummer, H., O’Brien, S., Pancin, J., Papachristodoulou, C., Papadopoulos, C., Paradela, C., Patronis, N., Pavlik, A., Pavlopoulos, P., Perrot, L., Pigni, M. T., Plag, R., Plompen, A., Plukis, A., Poch, A., Praena, J., Pretel, C., Quesada, J., Rauscher, T., Reifarth, R., Rosetti, M., Rubbia, C., Rudolf, G., Rullhusen, P., Salgado, J., Santos, C., Sarchiapone, L., Savvidis, I., Stephan, C., Tagliente, G., Tain, J. L., Tarrio, D., Tassan-Got, L., Tavora, L., Terlizzi, R., Vannini, G., Vaz, P., Ventura, A., Villamarin, D., Vincente, M. C., Vlachoudis, V., Vlastou, R., Voss, F., Walter, S., Wiescher, M., and Wisshak, K.

Published
2011
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44. Neutron-induced fission cross-section of 233U in the energy range 0.5 < En < 20 MeV

Author

Belloni, F., Calviani, M., Colonna, N., Mastinu, P., Milazzo, P. M., Abbondanno, U., Aerts, G., Álvarez, H., Alvarez-Velarde, F., Andriamonje, S., Andrzejewski, J., Audouin, L., Badurek, G., Baumann, P., Bečvář, F., Berthoumieux, E., Calviño, F., Cano-Ott, D., Capote, R., Carrapiço, C., Cennini, P., Chepel, V., Chiaveri, E., Cortes, G., Couture, A., Cox, J., Dahlfors, M., David, S., Dillmann, I., Domingo-Pardo, C., Dridi, W., Duran, I., Eleftheriadis, C., Embid-Segura, M., Ferrari, A., Ferreira-Marques, R., Fujii, K., Furman, W., Goncalves, I., Gonzalez-Romero, E., Goverdovski, A., Gramegna, F., Guerrero, C., Gunsing, F., Haas, B., Haight, R., Heil, M., Herrera-Martinez, A., Igashira, M., Jericha, E., Käppeler, F., Kadi, Y., Karadimos, D., Karamanis, D., Kerveno, M., Koehler, P., Kossionides, E., Krtička, M., Lamboudis, C., Leeb, H., Lindote, A., Lopes, I., Lozano, M., Lukic, S., Marganiec, J., Marrone, S., Martınez, T., Massimi, C., Meaze, M. H., Mengoni, A., Moreau, C., Mosconi, M., Neves, F., Oberhummer, H., O’Brien, S., Pancin, J., Papachristodoulou, C., Papadopoulos, C., Paradela, C., Patronis, N., Pavlik, A., Pavlopoulos, P., Perrot, L., Pigni, M. T., Plag, R., Plompen, A., Plukis, A., Poch, A., Praena, J., Pretel, C., Quesada, J., Rauscher, T., Reifarth, R., Rosetti, M., Rubbia, C., Rudolf, G., Rullhusen, P., Salgado, J., Santos, C., Sarchiapone, L., Savvidis, I., Stephan, C., Tagliente, G., Tain, J. L., Tassan-Got, L., Tavora, L., Terlizzi, R., Vannini, G., Vaz, P., Ventura, A., Villamarin, D., Vincente, M. C., Vlachoudis, V., Vlastou, R., Voss, F., Walter, S., Wiescher, M., Wisshak, K., and The n_TOF Collaboration

Published
2011
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46. Measurement of the 244Cm and 246Cm neutron-induced cross sections at the n_TOF facility

Author

Alcayne V., Kimura A., Mendoza E., Cano-Ott D., Aberle O., Amaducci S., Andrzejewski J., Audouin L., Babiano-Suarez V., Bacak M., Barbagallo M., Becares V., Becvar F., Bellia G., Berthoumieux E., Billowes J., Bosnar D., Brown A. S., Busso M., Caamano M., Caballero L., Calviani M., Calvino F., Casanovas A., Cerutti F., Chen Y. H., Chiaveri E., Colonna N., Cortes G. P., Cortes-Giraldo M. A., Cosentino L., Cristallo S., Damone L. A., Diakaki M., Dietz M., Domingo-Pardo C., Dressler R., Dupont E., Duran I., Eleme Z., Fernandez-Domingez B., Ferrari A., Ferro-Goncalves I., Finocchiaro P., Furman V., Gawlik A., Gilardoni S., Glodariu T., Gobel K., Gonzalez-Romero E., Guerrero C., Gunsing F., Heinitz S., Heyse J., Jenkins D. G., Kadi Y., Kappeler F., Kivel N., Kokkoris M., Kopatch Y., Krticka M., Kurtulgil D., Ladarescu I., Lederer-Woods C., Lerendegui-Marco J., Meo S. L., Lonsdale S. -J., Macina D., Manna A., Martinez T., Masi A., 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., Ogallar F., Oprea A., Patronis N., Pavlik A., Perkowski J., Piersanti L., Porras I., Praena J., Quesada J. M., Radeck D., Doval D. R., Rausher T., Reifarth R., Rochman D., Rubbia C., Sabate-Gilarte M., Saxena A., Schillebeeckx P., Schumann D., Smith A. G., Sosnin N., Stamatopoulos A., Tagliente G., Tain J. L., Talip Z., Tarifeno-Saldivia A. E., Tassan-Got L., 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., Zugec P., Alcayne, V., Kimura, A., Mendoza, E., Cano-Ott, D., Aberle, O., Amaducci, S., Andrzejewski, J., Audouin, L., Babiano-Suarez, V., Bacak, M., Barbagallo, M., Becares, V., Becvar, F., Bellia, G., Berthoumieux, E., Billowes, J., Bosnar, D., Brown, A. S., Busso, M., Caamano, M., Caballero, L., Calviani, M., Calvino, F., Casanovas, A., Cerutti, F., Chen, Y. H., Chiaveri, E., Colonna, N., Cortes, G. P., Cortes-Giraldo, M. A., Cosentino, L., Cristallo, S., Damone, L. A., Diakaki, M., Dietz, M., Domingo-Pardo, C., Dressler, R., Dupont, E., Duran, I., Eleme, Z., Fernandez-Domingez, B., Ferrari, A., Ferro-Goncalves, I., Finocchiaro, P., Furman, V., Gawlik, A., Gilardoni, S., Glodariu, T., Gobel, K., Gonzalez-Romero, E., Guerrero, C., Gunsing, F., Heinitz, S., Heyse, J., Jenkins, D. G., Kadi, Y., Kappeler, F., Kivel, N., Kokkoris, M., Kopatch, Y., Krticka, M., Kurtulgil, D., Ladarescu, I., Lederer-Woods, C., Lerendegui-Marco, J., Meo, S. L., Lonsdale, S. -J., Macina, D., Manna, A., Martinez, T., Masi, A., 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., Ogallar, F., Oprea, A., Patronis, N., Pavlik, A., Perkowski, J., Piersanti, L., Porras, I., Praena, J., Quesada, J. M., Radeck, D., Doval, D. R., Rausher, T., Reifarth, R., Rochman, D., Rubbia, C., Sabate-Gilarte, M., Saxena, A., Schillebeeckx, P., Schumann, D., Smith, A. G., Sosnin, N., Stamatopoulos, A., Tagliente, G., Tain, J. L., Talip, Z., Tarifeno-Saldivia, A. E., Tassan-Got, L., 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 Zugec, P.

Abstract

The neutron capture reactions of the 244Cm and 246Cm isotopes open the path for the formation of heavier Cm isotopes and of heavier elements such as Bk and Cf in a nuclear reactor. In addition, both isotopes belong to the minor actinides with a large contribution to the decay heat and to the neutron emission in irradiated fuels proposed for the transmutation of nuclear waste and fast critical reactors. The available experimental data for both isotopes are very scarce. We measured the neutron capture cross section with isotopically enriched samples of 244Cm and 246Cm provided by JAEA. The measurement covers the range from 1 eV to 250 eV in the n_TOF Experimental Area 2 (EAR-2). In addition, a normalization measurement with the 244Cm sample was performed at Experimental Area 1 (EAR-1) with the Total Absorption Calorimeter (TAC).

Published
2019

47. 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
Full Text
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48. Galeras Volcano: International Workshop and Eruption

Author

Muñoz, F. A., primary, Calvache, M. L., additional, Cortes, G. P., additional, Gomez, D. M., additional, Narvaez, L., additional, Ordonez, M., additional, Ortega, A., additional, Torres, R., additional, Silva, B., additional, Williams, S. N., additional, Sanders, C. O., additional, and Stix, J., additional

Published
1993
Full Text
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49. Importance of electron cyclotron wave energy transport in ITER

Author

Albajar, F., Bornatici, M., Cortes, G., Dies, J., Engelmann, F., Garcia, J., and Izquierdo, J.

Abstract

The importance of electron cyclotron (EC) wave emission to the local electron power balance is analysed for various ITER operation regimes and, for comparison, for typical working conditions of FIRE, IGNITOR and the reactor-grade ITER concept as considered during the Engineering Design Phase (ITER-EDA). To cover the non-local effects in EC wave emission as well, the CYTRAN routine along with the ASTRA transport code is used. As a result, EC wave emission is shown to be a significant contributor to core electron cooling if the core electron temperature is about 35 keV or higher, as expected for ITER and tokamak reactor steady-state operation; in fact, it becomes the dominant core electron cooling mechanism at temperatures exceeding 40 keV, as such affecting the core plasma power balance in an important way.

Published
2005

50. Agreement between analytic values of blood samples extracted with peripheral catheters and those extracted using direct puncture.

Author

Granados Gámez F, Granados Gámez G, Gómez Rubio J, Caparros Cortes G, Pícher Vidal DJ, and Gómez Gómez P

Abstract

Copyright of Enfermería Clínica is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Published
2003

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