Search

Your search keyword '"Chen Y. H."' showing total 5,338 results
Start Over Author "Chen Y. H."
5,338 results on '"Chen Y. H."'

1. Extragalactic fast X-ray transient from a weak relativistic jet associated with a Type Ic-BL supernova

Author

Sun, H., Li, W. -X., Liu, L. -D., Gao, H., Wang, X. -F., Yuan, W., Zhang, B., Filippenko, A. V., Xu, D., An, T., Ai, S., Brink, T. G., Liu, Y., Liu, Y. -Q., Wang, C. -Y., Wu, Q. -Y., Wu, X. -F., Yang, Y., Zhang, B. -B., Zheng, W. -K., Ahumada, T., Dai, Z. -G., Delaunay, J., Elias-Rosa, N., Benetti, S., Fu, S. -Y., Howell, D. A., Huang, Y. -F., Kasliwal, M. M., Karambelkar, V., Stein, R., Lei, W. -H., Lian, T. -Y., Peng, Z. -K., Ridnaia, A. V., Svinkin, D. S., Wang, X. -Y., Wang, A. -L., Wei, D. -M., An, J., Andrews, M., Bai, J. -M, Dai, C. -Y., Ehgamberdiev, S. A., Fan, Z., Farah, J., Feng, H. -C., Fynbo, J. P. U., Guo, W. -J., Guo, Z., Hu, M. -K., Hu, J. -W., Jiang, S. -Q., Jin, J. -J., Li, A., Li, J. -D., Li, R. -Z., Liang, Y. -F., Ling, Z. -X., Liu, X., Mao, J. -R., McCully, C., Mirzaqulov, D., Newsome, M., Gonzalez, E. Padilla, Pan, X., Terreran, G., Tinyanont, S., Wang, B. -T., Wang, L. -Z., Wen, X. -D., Xiang, D. -F., Xue, S. -J., Yang, J., Zhu, Z. -P., Cai, Z. -M., Castro-Tirado, A. J., Chen, F. -S., Chen, H. -L., Chen, T. -X., Chen, W., Chen, Y. -H., Chen, Y. -F., Chen, Y., Cheng, H. -Q., Cordier, B., Cui, C. -Z., Cui, W. -W., Dai, Y. -F., Fan, D. -W., Feng, H., Guan, J., Han, D. -W., Hou, D. -J., Hu, H. -B., Huang, M. -H., Huo, J., Jia, S. -M., Jia, Z. -Q., Jiang, B. -W., Jin, C. -C., Jin, G., Kuulkers, E., Li, C. -K., Li, D. -Y., Li, J. -F., Li, L. -H., Li, M. -S., Li, W., Li, Z. -D., Liu, C. -Z, Liu, H. -Y., Liu, H. -Q., Liu, M. -J., Lu, F. -J., Luo, L. -D., Ma, J., Mao, X., Nandra, K., O'Brien, P., Pan, H. -W., Rau, A., Rea, N., Sanders, J., Song, L. -M., Sun, S. -L., Sun, X. -J., Tan, Y. -Y., Tang, Q. -J., Tao, Y. -H., Wang, H., Wang, J., Wang, L., Wang, W. -X., Wang, Y. -L., Wang, Y. -S., Xiong, D. -R., Xu, H. -T., Xu, J. -J., Xu, X. -P., Xu, Y. -F., Xu, Z., Xue, C. -B., Xue, Y. -L., Yan, A. -L., Yang, H. -N., Yang, X. -T., Yang, Y. -J., Zhang, C., Zhang, J., Zhang, M., Zhang, S. -N., Zhang, W. -D., Zhang, W. -J., Zhang, Y. -H., Zhang, Z., Zhang, Z. -L., Zhao, D. -H., Zhao, H. -S., Zhao, X. -F., Zhao, Z. -J., Zhou, Y. -L., Zhu, Y. -X., and Zhu, Z. -C.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

Massive stars end their life as core-collapse supernovae, amongst which some extremes are Type Ic broad-lined supernovae associated with long-duration gamma-ray bursts (LGRBs) having powerful relativistic jets. Their less-extreme brethren make unsuccessful jets that are choked inside the stars, appearing as X-ray flashes or low-luminosity GRBs. On the other hand, there exists a population of extragalactic fast X-ray transients (EFXTs) with timescales ranging from seconds to thousands of seconds, whose origins remain obscure. Known sources that contribute to the observed EFXT population include the softer analogs of LGRBs, shock breakouts of supernovae, or unsuccessful jets. Here, we report the discovery of the bright X-ray transient EP240414a detected by the Einstein Probe (EP), which is associated with the Type Ic supernova SN 2024gsa at a redshift of 0.401. The X-ray emission evolution is characterised by a very soft energy spectrum peaking at < 1.3 keV, which makes it distinct from known LGRBs, X-ray flashes, or low-luminosity GRBs. Follow-up observations at optical and radio bands revealed the existence of a weak relativistic jet that interacts with an extended shell surrounding the progenitor star. Located on the outskirts of a massive galaxy, this event reveals a new population of explosions of Wolf-Rayet stars characterised by a less powerful engine that drives a successful but weak jet, possibly owing to a progenitor star with a smaller core angular momentum than in traditional LGRB progenitors., Comment: 43 pages, 9 figures, 4 tables, submitted. Comments are welcome

Published
2024

2. Measurement and analysis of the $^{246}$Cm and $^{248}$Cm neutron capture cross-sections at the EAR2 of the n TOF facility

Author

Alcayne, V., Kimura, A., Mendoza, E., Cano-Ott, D., Aberle, O., Álvarez-Velarde, F., Amaducci, S., Andrzejewski, J., Audouin, L., Bécares, V., Babiano-Suarez, V., Bacak, M., Barbagallo, M., Bečvář, F., Bellia, G., Berthoumieux, E., Billowes, J., Bosnar, D., Brown, A., Busso, M., Caamaño, M., Caballero-Ontanaya, L., Calviño, F., Calviani, M., Casanovas, A., Cerutti, F., Chen, Y. H., Chiaveri, E., Colonna, N., Cortés, G., Cortés-Giraldo, M. A., Cosentino, L., Cristallo, S., Damone, L. A., Diakaki, M., Dietz, M., Domingo-Pardo, C., Dressler, R., Dupont, E., Durán, I., Eleme, Z., Fernández-Domınguez, B., Ferrari, A., Finocchiaro, P., Furman, V., Göbel, K., Garg, R., Gawlik-Ramiega, A., Gilardoni, S., Glodariu, T., Gonçalves, I. F., González-Romero, E., Guerrero, C., Gunsing, F., Harada, H., Heinitz, S., Heyse, J., Jenkins, D. G., Jericha, E., Käppeler, F., Kadi, Y., Kivel, N., Kokkoris, M., Kopatch, Y., Krtička, M., Kurtulgil, D., Ladarescu, I., Lederer-Woods, C., Leeb, H., Lerendegui-Marco, J., Meo, S. Lo, Lonsdale, S. J., Macina, D., Manna, A., Martınez, T., Masi, A., Massimi, C., Mastinu, P., Mastromarco, M., Matteucci, F., Maugeri, E. A., Mazzone, A., Mengoni, A., Michalopoulou, V., Milazzo, P. M., Mingrone, F., Musumarra, A., Negret, A., Nolte, R., Ogállar, F., Oprea, A., Patronis, N., Pavlik, A., de Rada, A. Pérez, Perkowski, J., Persanti, L., Porras, I., Praena, J., Quesada, J. M., Radeck, D., Ramos-Doval, D., Rauscher, T., Reifarth, R., Rochman, D., Romanets, Y., Rubbia, C., Sabaté-Gilarte, M., Saxena, A., Schillebeeckx, P., Schumann, D., Smith, A. G., Sosnin, N. V., Stamatopoulos, A., Tagliente, G., Tain, J. L., Talip, T., Tarifeño-Saldivia, A., Tassan-Got, L., Torres-Sánchez, P., Tsinganis, A., Ulrich, J., Urlass, S., Valenta, S., Vannini, G., Variale, V., Vaz, P., Ventura, A., Vlachoudis, V., Vlastou, R., Wallner, A., Woods, P. J., Wright, T., and Žugec, P.

Subjects
Nuclear Experiment
Abstract

The $^{246}$Cm(n,$\gamma$) and $^{248}$Cm(n,$\gamma$) cross-sections have been measured at the Experimental Area 2 (EAR2) of the n_TOF facility at CERN with three C$_6$D$_6$ detectors. This measurement is part of a collective effort to improve the capture cross-section data for Minor Actinides (MAs), which are required to estimate the production and transmutation rates of these isotopes in light water reactors and innovative reactor systems. In particular, the neutron capture in $^{246}$Cm and $^{248}$Cm open the path for the formation of other Cm isotopes and heavier elements such as Bk and Cf and the knowledge of (n,$\gamma$) cross-sections of these Cm isotopes plays an important role in the transport, transmutation and storage of the spent nuclear fuel. The reactions $^{246}$Cm(n,$\gamma$) and $^{248}$Cm(n,$\gamma$) have been the two first capture measurements analyzed at n_TOF EAR2. Until this experiment and two recent measurements performed at J-PARC, there was only one set of data of the capture cross-sections of $^{246}$Cm and $^{248}$Cm, that was obtained in 1969 in an underground nuclear explosion experiment. In the measurement at n_TOF a total of 13 resonances of $^{246}$Cm between 4 and 400 eV and 5 of $^{248}$Cm between 7 and 100 eV have been identified and fitted. The radiative kernels obtained for $^{246}$Cm are compatible with JENDL-5, but some of them are not with JENDL-4, which has been adopted by JEFF-3.3 and ENDF/B-VIII.0. The radiative kernels obtained for the first three $^{248}$Cm resonances are compatible with JENDL-5, however, the other two are not compatible with any other evaluation and are 20% and 60% larger than JENDL-5.

Published
2024

3. Measurement of the 241Am(n,γ) cross section at the n_TOF facility at CERN

Author

Oprea A., Gunsing F., Schillebeeckx P., Aberle O., Bacak M., Berthoumieux E., Cano-Ott D., Diakaki M., Dupont E., Geslot B., Glodariu† T., Heyse J., Mendoza E., Negret A., Alcayne V., Amaducci S., Andrzejewski J., Audouin L., Bécares V., Babiano-Suarez V., Barbagallo M., Bečvář F., Bellia G., Billowes J., Bosnar D., Brown A., Busso M., Caamaño M., Caballero-Ontanaya L., Calviño F., Calviani M., Casanovas A., Cerutti F., Chen Y. H., Chiaveri E., Colonna N., Cortés G., Cortés-Giraldo M. A., Cosentino L., Cristallo S., Damone L. A., Dietz M., Domingo-Pardo C., Dressler R., Durán I., Eleme Z., Fernández-Domínguez B., Ferrari A., Finocchiaro P., Furman V., Göbel K., Garg R., Gawlik-Ramięga A., Gilardoni S., Gonçalves I. F., González-Romero E., Guerrero C., Harada H., Heinitz S., Jenkins D. G., Jericha E., Käppeler† F., Kaur G., Kadi Y., Kimura A., Kivel N., Kokkoris M., Kopatch Y., Krtička M., Kurtulgil D., Ladarescu I., Lederer-Woods C., Leeb H., Lerendegui-Marco J., Lo Meo S., Lonsdale S. J., Macina D., Manna A., Martínez T., Masi A., Massimi C., Mastinu P., Mastromarco M., Matteucci F., Maugeri E. A., Mazzone A., Mengoni A., Michalopoulou V., Milazzo P. M., Mingrone F., Musumarra A., Nolte R., Ogállar F., Patronis N., Pavlik A., Perkowski J., Piersanti L., Porras I., Praena J., Quesada J. M., Radeck D., Ramos-Doval D., Rauscher T., Reifarth R., Rochman D., Rubbia C., Sabaté-Gilarte M., Saxena A., Schumann D., Smith A. G., Sosnin N. V., Stamatopoulos A., Tagliente G., Tain J. L., Talip T., Tarifeño-Saldivia A., Tassan-Got L., Torres-Sánchez P., Tsinganis A., Ulrich J., Urlass S., Valenta S., Vannini G., Variale V., Vaz P., Ventura A., Vlachoudis V., Vlastou R., Wallner A., Woods P. J., Wright T., and Žugec P.

Subjects
Physics, QC1-999
Abstract

The neutron capture cross section of 241Am is an important quantity for nuclear energy production and fuel cycle scenarios. Several measurements have been performed in recent years with the aim to reduce existing uncertainties in evaluated data. Two previous measurements, performed at the 185 m flight-path station EAR1 of the neutron time-of-flight facility n_TOF at CERN, have permitted to substantially extend the resolved resonance region, but suffered in the near-thermal energy range from the unfavorable signal-to-background ratio resulting from the combination of the high radioactivity of 241Am and the rather low thermal neutron flux. The here presented 241Am(n,γ) measurement, performed with C6D6 liquid scintillator gamma detectors at the 20 m flight-path station EAR2 of the n_TOF facility, took advantage of the much higher neutron flux. The current status of the analysis of the data, focussed on the low-energy region, will be described here.

Published
2023
Full Text
View/download PDF

4. 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
View/download PDF

5. The Stellar 72Ge(n, γ) Cross Section for weak s-process: A First Measurement at n_TOF

Author

Dietz M., Lederer-Woods C., Tattersall A., Battino U., Gunsing F., Heinitz S., Lerendegui-Marco J., Krtička M., Reifarth R., Valenta S., Aberle O., Amaducci S., Andrzejewski J., Audouin L., Bacak M., Balibrea J., Barbagallo M., Bečvář F., Berthoumieux E., Billowes J., Bosnar D., Brown A., Caamaño M., Calviño F., Calviani M., Cano-Ott D., Cardella R., Casanovas A., Cerutti F., Chen Y. H., Chiaveri E., Colonna N., Cortés G., Cortés-Giraldo M. A., Cosentino L., Damone L. A., Diakaki M., Domingo-Pardo C., Dressler R., Dupont E., Durán I., Fernández-Domínguez B., Ferrari A., Ferreira P., Finocchiaro P., Göbel K., García A. R., Gawlik-Ramie˛ga A., Gilardoni S., Glodariu† T., Gonçalves I. F., González-Romero E., Griesmayer E., Guerrero C., Harada H., Heyse J., Jenkins D. G., Jericha E., Käppeler† F., Kadi Y., Kahl D., Kalamara A., Kavrigin P., Kimura A., Kivel N., Kokkoris M., Kurtulgil D., Leal-Cidoncha E., Leeb H., Lo Meo S., Lonsdale S. J., Macina D., Manna A., Marganiec J., Martínez T., Masi A., Massimi C., Mastinu P., Mastromarco M., Maugeri E. A., Mazzone A., Mendoza E., Mengoni A., Milazzo P. M., Mingrone F., Musumarra A., Negret A., Nolte R., Oprea A., Patronis N., Pavlik A., Perkowski J., Porras I., Praena J., Quesada J. M., Radeck D., Rauscher T., Rubbia C., Ryan J. A., Sabaté-Gilarte M., Saxena A., Schillebeeckx P., Schumann D., Smith A. G., Sosnin N. V., Stamatopoulos A., Tagliente G., Tain J. L., Tarifeño-Saldivia A., Tassan-Got L., Vannini G., Variale V., Vaz P., Ventura A., Vlachoudis V., Vlastou R., Wallner A., Warren S., Weiss C., Woods P. J., Wright T., and Žugec P.

Subjects
Physics, QC1-999
Abstract

The slow neutron capture process (s-process) is responsible for producing about half of the elemental abundances heavier than iron in the universe. Neutron capture cross sections on stable isotopes are a key nuclear physics input for s-process studies. The 72Ge(n, γ) Maxwellian-Averaged Cross Section (MACS) has an important influence on the production of isotopes between Ge and Zr in the weak s-process in massive stars and so far only theoretical estimations are available. An experiment was carried out at the neutron time-of-flight facility n_TOF at CERN to measure the 72Ge(n, γ) reaction for the first time at stellar neutron energies. The capture measurement was performed using an enriched 72GeO2 sample at a flight path length of 184 m, which provided high neutron energy resolution. The prompt gamma rays produced after neutron capture were detected with a set of liquid scintillation detectors (C6D6). The neutron capture yield is derived from the counting spectra taking into account the neutron flux and the gamma-ray detection efficiency using the Pulse Height Weighting Technique. Over 70 new neutron resonances were identified, providing an improved resolved reaction cross section to calculate experimental MACS values for the first time. The experiment, data analysis and the new MACS results will be presented including their impact on stellar nucleosynthesis, which was investigated using the post-processing nucleosynthesis code mppnp for a 25 solar mass model.

Published
2023
Full Text
View/download PDF

6. A bijection related to Bressoud's conjecture

Author

Chen, Y. H. and He, Thomas Y.

Subjects
Mathematics - Combinatorics
Abstract

Bressoud introduced the partition function $B(\alpha_1,\ldots,\alpha_\lambda;\eta,k,r;n)$, which counts the number of partitions with certain difference conditions. Bressoud posed a conjecture on the generating function for the partition function $B(\alpha_1,\ldots,\alpha_\lambda;\eta,k,r;n)$ in multi-summation form. In this article, we introduce a bijection related to Bressoud's conjecture. As an application, we give a new companion to the G\"ollnitz-Gordon identities.

Published
2024

7. Search for solar axions by Primakoff effect with the full dataset of the CDEX-1B Experiment

Author

Yang, L. T., Liu, S. K., Yue, Q., Kang, K. J., Li, Y. J., An, H. P., C., Greeshma, Chang, J. P., Chen, Y. H., Cheng, J. P., Dai, W. H., Deng, Z., Fang, C. H., Geng, X. P., Gong, H., Guo, Q. J., Guo, T., Guo, X. Y., He, L., He, J. R., Hu, J. W., Huang, H. X., Huang, T. C., Jiang, L., Karmakar, S., Li, H. B., Li, H. Y., Li, J. M., Li, J., Li, M. C., Li, Q. Y., Li, R. M. J., Li, X. Q., Li, Y. L., Liang, Y. F., Liao, B., Lin, F. K., Lin, S. T., Liu, J. X., Liu, Y. D., Liu, Y., Liu, Y. Y., Ma, H., Mao, Y. C., Nie, Q. Y., Pan, H., Qi, N. C., Ren, J., Ruan, X. C., Shen, M. B., Singh, M. K., Sun, T. X., Sun, W. L., Tang, C. J., Tian, Y., Wang, G. F., Wang, J. Z., Wang, L., Wang, Q., Wang, Y. F., Wang, Y. X., Wong, H. T., Wu, Y. C., Xing, H. Y., Xiong, K. Z., Xu, R., Xu, Y., Xue, T., Yan, Y. L., Yi, N., Yu, C. X., Yu, H. J., Zeng, M., Zeng, Z., Zhang, B. T., Zhang, F. S., Zhang, L., Zhang, P., Zhang, Z. H., Zhang, Z. Y., Zhao, J. Z., Zhao, K. K., Zhao, M. G., Zhou, J. F., Zhou, Z. Y., and Zhu, J. J.

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

We present the first limit on $g_{A\gamma}$ coupling constant using the Bragg-Primakoff conversion based on an exposure of 1107.5 kg days of data from the CDEX-1B experiment at the China Jinping Underground Laboratory. The data are consistent with the null signal hypothesis, and no excess signals are observed. Limits of the coupling $g_{A\gamma}<2.08\times10^{-9}$ GeV$^{-1}$ (95\% C.L.) are derived for axions with mass up to 100 eV/$c^2$. Within the hadronic model of KSVZ, our results exclude axion mass $>5.3~\rm{eV}/c^2$ at 95\% C.L., Comment: 7 pages, 5 figures

Published
2024

8. Soft X-ray prompt emission from a high-redshift gamma-ray burst EP240315a

Author

Liu, Y., Sun, H., Xu, D., Svinkin, D. S., Delaunay, J., Tanvir, N. R., Gao, H., Zhang, C., Chen, Y., Wu, X. -F., Zhang, B., Yuan, W., An, J., Bruni, G., Frederiks, D. D., Ghirlanda, G., Hu, J. -W., Li, A., Li, C. -K., Li, J. -D., Malesani, D. B., Piro, L., Raman, G., Ricci, R., Troja, E., Vergani, S. D., Wu, Q. -Y., Yang, J., Zhang, B. -B., Zhu, Z. -P., Postigo, A. de Ugarte, Demin, A. G., Dobie, D., Fan, Z., Fu, S. -Y., Fynbo, J. P. U., Geng, J. -J., Gianfagna, G., Hu, Y. -D., Huang, Y. -F., Jiang, S. -Q., Jonker, P. G., Julakanti, Y., Kennea, J. A., Kokomov, A. A., Kuulkers, E., Lei, W. -H., Leung, J. K., Levan, A. J., Li, D. -Y., Li, Y., Littlefair, S. P., Liu, X., Lysenko, A. L., Ma, Y. -N., Martin-Carrillo, A., O'Brien, P., Parsotan, T., Quirola-Vasquez, J., Ridnaia, A. V., Ronchini, S., Rossi, A., Mata-Sanchez, D., Schneider, B., Shen, R. -F., Thakur, A. L., Tohuvavohu, A., Torres, M. A. P., Tsvetkova, A. E., Ulanov, M. V., Wei, J. -J., Xiao, D., Yin, Y. -H. I., Bai, M., Burwitz, V., Cai, Z. -M., Chen, F. -S., Chen, H. -L., Chen, T. -X., Chen, W., Chen, Y. -F., Chen, Y. -H., Cheng, H. -Q., Cui, C. -Z., Cui, W. -W., Dai, Y. -F., Dai, Z. -G., Eder, J., Fan, D. -W., Feldman, C., Feng, H., Feng, Z., Friedrich, P., Gao, X., Guan, J., Han, D. -W, Han, J., Hou, D. -J., Hu, H. -B., Hu, T., Huang, M. -H., Huo, J., Hutchinson, I., Ji, Z., Jia, S. -M., Jia, Z. -Q., Jiang, B. -W., Jin, C. -C., Jin, G., Jin, J. -J., Keereman, A., Lerman, H., Li, J. -F., Li, L. -H., Li, M. -S., Li, W., Li, Z. -D., Lian, T. -Y., Liang, E. -W., Ling, Z. -X., Liu, C. -Z., Liu, H. -Y., Liu, H. -Q., Liu, M. -J., Liu, Y. -R., Lu, F. -J., LU, H. -J., Luo, L. -D., Ma, F. L., Ma, J., Mao, J. -R., Mao, X., McHugh, M., Meidinger, N., Nandra, K., Osborne, J. P., Pan, H. -W., Pan, X., Ravasio, M. E., Rau, A., Rea, N., Rehman, U., Sanders, J., Santovincenzo, A., Song, L. -M., Su, J., Sun, L. -J., Sun, S. -L., Sun, X. -J., Tan, Y. -Y., Tang, Q. -J., Tao, Y. -H., Tong, J. -Z., Wang, H., Wang, J., Wang, L., Wang, W. -X., Wang, X. -F., Wang, X. -Y., Wang, Y. -L., Wang, Y. -S., Wei, D. -M., Willingale, R., Xiong, S. -L., Xu, H. -T., Xu, J. -J., Xu, X. -P., Xu, Y. -F., Xu, Z., Xue, C. -B., Xue, Y. -L., Yan, A. -L., Yang, F., Yang, H. -N., Yang, X. -T., Yang, Y. -J, Yu, Y. -W., Zhang, J., Zhang, M., Zhang, S. -N., Zhang, W. -D., Zhang, W. -J., Zhang, Y. -H., Zhang, Z., Zhang, Z. -L., Zhao, D. -H., Zhao, H. -S., Zhao, X. -F., Zhao, Z. -J., Zhou, L. -X., Zhou, Y. -L., Zhu, Y. -X., Zhu, Z. -C., and Zuo, X. -X.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

Long gamma-ray bursts (GRBs) are believed to originate from core collapse of massive stars. High-redshift GRBs can probe the star formation and reionization history of the early universe, but their detection remains rare. Here we report the detection of a GRB triggered in the 0.5--4 keV band by the Wide-field X-ray Telescope (WXT) on board the Einstein Probe (EP) mission, designated as EP240315a, whose bright peak was also detected by the Swift Burst Alert Telescope and Konus-Wind through off-line analyses. At a redshift of $z=4.859$, EP240315a showed a much longer and more complicated light curve in the soft X-ray band than in gamma-rays. Benefiting from a large field-of-view ($\sim$3600 deg$^2$) and a high sensitivity, EP-WXT captured the earlier engine activation and extended late engine activity through a continuous detection. With a peak X-ray flux at the faint end of previously known high-$z$ GRBs, the detection of EP240315a demonstrates the great potential for EP to study the early universe via GRBs., Comment: 41 pages, 8 figures, 7 tables

Published
2024

9. First Search for Light Fermionic Dark Matter Absorption on Electrons Using Germanium Detector in CDEX-10 Experiment

Author

Liu, J. X., Yang, L. T., Yue, Q., Kang, K. J., Li, Y. J., An, H. P., C., Greeshma, Chang, J. P., Chen, Y. H., Cheng, J. P., Dai, W. H., Deng, Z., Fang, C. H., Geng, X. P., Gong, H., Guo, Q. J., Guo, T., Guo, X. Y., He, L., He, J. R., Hu, J. W., Huang, H. X., Huang, T. C., Jiang, L., Karmakar, S., Li, H. B., Li, H. Y., Li, J. M., Li, J., Li, M. C., Li, Q. Y., Li, R. M. J., Li, X. Q., Li, Y. L., Liang, Y. F., Liao, B., Lin, F. K., Lin, S. T., Liu, S. K., Liu, Y. D., Liu, Y., Liu, Y. Y., Ma, H., Mao, Y. C., Nie, Q. Y., Pan, H., Qi, N. C., Ren, J., Ruan, X. C., Shen, M. B., Singh, M. K., Sun, T. X., Sun, W. L., Tang, C. J., Tian, Y., Wang, G. F., Wang, J. Z., Wang, L., Wang, Q., Wang, Y. F., Wang, Y. X., Wong, H. T., Wu, Y. C., Xing, H. Y., Xiong, K. Z., Xu, R., Xu, Y., Xue, T., Yan, Y. L., Yi, N., Yu, C. X., Yu, H. J., Zeng, M., Zeng, Z., Zhang, B. T., Zhang, F. S., Zhang, L., Zhang, P., Zhang, Z. H., Zhang, Z. Y., Zhao, J. Z., Zhao, K. K., Zhao, M. G., Zhou, J. F., Zhou, Z. Y., and Zhu, J. J.

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

We present the first results of the search for sub-MeV fermionic dark matter absorbed by electron targets of Germanium using the 205.4~kg$\cdot$day data collected by the CDEX-10 experiment, with the analysis threshold of 160~eVee. No significant dark matter (DM) signals over the background are observed. Results are presented as limits on the cross section of DM--electron interaction. We present new constraints of cross section in the DM range of 0.1--10 keV/$c^2$ for vector and axial-vector interaction. The upper limit on the cross section is set to be $\rm 5.5\times10^{-46}~cm^2$ for vector interaction, and $\rm 1.8\times10^{-46}~cm^2$ for axial-vector interaction at DM mass of 5 keV/$c^2$., Comment: 6 pages, 4 figures

Published
2024

10. Constraints on the Blazar-Boosted Dark Matter from the CDEX-10 Experiment

Author

Xu, R., Yang, L. T., Yue, Q., Kang, K. J., Li, Y. J., An, H. P., C., Greeshma, Chang, J. P., Chen, Y. H., Cheng, J. P., Dai, W. H., Deng, Z., Fang, C. H., Geng, X. P., Gong, H., Guo, Q. J., Guo, T., Guo, X. Y., He, L., He, S. M., Hu, J. W., Huang, H. X., Huang, T. C., Jiang, L., Karmakar, S., Li, H. B., Li, H. Y., Li, J. M., Li, J., Li, Q. Y., Li, R. M. J., Li, X. Q., Li, Y. L., Liang, Y. F., Liao, B., Lin, F. K., Lin, S. T., Liu, J. X., Liu, S. K., Liu, Y. D., Liu, Y., Liu, Y. Y., Ma, H., Mao, Y. C., Nie, Q. Y., Ning, J. H., Pan, H., Qi, N. C., Ren, J., Ruan, X. C., Singh, M. K., Sun, T. X., Tang, C. J., Tian, Y., Wang, G. F., Wang, J. Z., Wang, L., Wang, Q., Wang, Y. F., Wang, Y. X., Wong, H. T., Wu, S. Y., Wu, Y. C., Xing, H. Y., Xu, Y., Xue, T., Yan, Y. L., Yi, N., Yu, C. X., Yu, H. J., Yue, J. F., Zeng, M., Zeng, Z., Zhang, B. T., Zhang, F. S., Zhang, L., Zhang, Z. H., Zhang, Z. Y., Zhao, J. Z., Zhao, K. K., Zhao, M. G., Zhou, J. F., Zhou, Z. Y., and Zhu, J. J.

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

We report new constraints on light dark matter (DM) boosted by blazars using the 205.4 kg day data from the CDEX-10 experiment located at the China Jinping Underground Laboratory. Two representative blazars, TXS 0506+56 and BL Lacertae are studied. The results derived from TXS 0506+56 exclude DM-nucleon elastic scattering cross sections from $4.6\times 10^{-33}\ \rm cm^2$ to $1\times10^{-26}\ \rm cm^2$ for DM masses between 10 keV and 1 GeV, and the results derived from BL Lacertae exclude DM-nucleon elastic scattering cross sections from $2.4\times 10^{-34}\ \rm cm^2$ to $1\times10^{-26}\ \rm cm^2$ for the same range of DM masses. The constraints correspond to the best sensitivities among solid-state detector experiments in the sub-MeV mass range., Comment: 7 pages, 4 figures

Published
2024

11. Probing Dark Matter Particles from Evaporating Primordial Black Holes via Electron Scattering in the CDEX-10 Experiment

Author

Zhang, Z. H., Yang, L. T., Yue, Q., Kang, K. J., Li, Y. J., An, H. P., C., Greeshma, Chang, J. P., Chen, Y. H., Cheng, J. P., Dai, W. H., Deng, Z., Fang, C. H., Geng, X. P., Gong, H., Guo, Q. J., Guo, T., Guo, X. Y., He, L., He, S. M., Hu, J. W., Huang, H. X., Huang, T. C., Jiang, L., Karmakar, S., Li, H. B., Li, H. Y., Li, J. M., Li, J., Li, Q. Y., Li, R. M. J., Li, X. Q., Li, Y. L., Liang, Y. F., Liao, B., Lin, F. K., Lin, S. T., Liu, J. X., Liu, S. K., Liu, Y. D., Liu, Y., Liu, Y. Y., Ma, H., Mao, Y. C., Nie, Q. Y., Ning, J. H., Pan, H., Qi, N. C., Ren, J., Ruan, X. C., Singh, M. K., Sun, T. X., Tang, C. J., Tian, Y., Wang, G. F., Wang, J. Z., Wang, L., Wang, Q., Wang, Y. F., Wang, Y. X., Wong, H. T., Wu, S. Y., Wu, Y. C., Xing, H. Y., Xu, R., Xu, Y., Xue, T., Yan, Y. L., Yi, N., Yu, C. X., Yu, H. J., Yue, J. F., Zeng, M., Zeng, Z., Zhang, B. T., Zhang, F. S., Zhang, L., Zhang, Z. Y., Zhao, J. Z., Zhao, K. K., Zhao, M. G., Zhou, J. F., Zhou, Z. Y., and Zhu, J. J.

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

Dark matter (DM) is a major constituent of the Universe. However, no definite evidence of DM particles (denoted as ``$\chi$") has been found in DM direct detection (DD) experiments to date. There is a novel concept of detecting $\chi$ from evaporating primordial black holes (PBHs). We search for $\chi$ emitted from PBHs by investigating their interaction with target electrons. The examined PBH masses range from 1$\times$10$^{15}$ to 7$\times$10$^{16}$ g under the current limits of PBH abundance $f_{PBH}$. Using 205.4 kg$\cdot$day data obtained from the CDEX-10 experiment conducted in the China Jinping Underground Laboratory, we exclude the $\chi$--electron ($\chi$--$e$) elastic-scattering cross section $\sigma_{\chi e} \sim 5\times10^{-29}$ cm$^2$ for $\chi$ with a mass $m_{\chi}\lesssim$ 0.1 keV from our results. With the higher radiation background but lower energy threshold (160 eV), CDEX-10 fill a part of the gap in the previous work. If ($m_{\chi}$, $\sigma_{\chi e}$) can be determined in the future, DD experiments are expected to impose strong constraints on $f_{PBH}$ for large $M_{PBH}$s., Comment: 9 pages, 6 figures, 3 tables. Version updated to match SCPMA version

Published
2024
Full Text
View/download PDF

13. An overpartition analogue of Bressoud conjecture for even moduli

Author

Chen, Y. H., Gu, T. T., He, Thomas Y., Tang, F., and Wei, J. J.

Subjects
Mathematics - Combinatorics
Abstract

In 1980, Bressoud conjectured a combinatorial identity $A_j=B_j$ for $j=0$ or $1$. In this paper, we introduce a new partition function $\overline{B}_0$ which can be viewed as an overpartition analogue of the partition function $B_0$. An overpartition is a partition such that the last occurrence of a part can be overlined. We build a bijection to get a relationship between $\overline{B}_0$ and $B_1$, based on which an overpartition analogue of Bressoud's conjecture for $j=0$ is obtained.

Published
2023

14. Experimental Limits on Solar Reflected Dark Matter with a New Approach on Accelerated-Dark-Matter-Electron Analysis in Semiconductors

Author

Zhang, Z. Y., Yang, L. T., Yue, Q., Kang, K. J., Li, Y. J., An, H. P., C., Greeshma, Chang, J. P., Chen, Y. H., Cheng, J. P., Dai, W. H., Deng, Z., Fang, C. H., Geng, X. P., Gong, H., Guo, Q. J., Guo, T., Guo, X. Y., He, L., He, S. M., Hu, J. W., Huang, H. X., Huang, T. C., Jiang, L., Karmakar, S., Li, H. B., Li, H. Y., Li, J. M., Li, J., Li, Q. Y., Li, R. M. J., Li, X. Q., Li, Y. L., Liang, Y. F., Liao, B., Lin, F. K., Lin, S. T., Liu, J. X., Liu, S. K., Liu, Y. D., Liu, Y., Liu, Y. Y., Ma, H., Mao, Y. C., Nie, Q. Y., Ning, J. H., Pan, H., Qi, N. C., Ren, J., Ruan, X. C., Singh, M. K., Sun, T. X., Tang, C. J., Tian, Y., Wang, G. F., Wang, J. Z., Wang, L., Wang, Q., Wang, Y. F., Wang, Y. X., Wong, H. T., Wu, S. Y., Wu, Y. C., Xing, H. Y., Xu, R., Xu, Y., Xue, T., Yan, Y. L., Yi, N., Yu, C. X., Yu, H. J., Yue, J. F., Zeng, M., Zeng, Z., Zhang, B. T., Zhang, F. S., Zhang, L., Zhang, Z. H., Zhao, J. Z., Zhao, K. K., Zhao, M. G., Zhou, J. F., Zhou, Z. Y., and Zhu, J. J.

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

Recently a dark matter-electron (DM-electron) paradigm has drawn much attention. Models beyond the standard halo model describing DM accelerated by high energy celestial bodies are under intense examination as well. In this Letter, a velocity components analysis (VCA) method dedicated to swift analysis of accelerated DM-electron interactions via semiconductor detectors is proposed and the first HPGe detector-based accelerated DM-electron analysis is realized. Utilizing the method, the first germanium based constraint on sub-GeV solar reflected DM-electron interaction is presented with the 205.4 kg$\cdot$day dataset from the CDEX-10 experiment. In the heavy mediator scenario, our result excels in the mass range of 5$-$15 keV/$c^2$, achieving a 3 orders of magnitude improvement comparing with previous semiconductor experiments. In the light mediator scenario, the strongest laboratory constraint for DM lighter than 0.1 MeV/$c^2$ is presented. The result proves the feasibility and demonstrates the vast potential of the VCA technique in future accelerated DM-electron analyses with semiconductor detectors., Comment: 7 pages, 4 figures. Version updated to match PRL version

Published
2023
Full Text
View/download PDF

15. Projected WIMP sensitivity of the CDEX-50 dark matter experiment

Author

Geng, X. P., Yang, L. T., Yue, Q., Kang, K. J., Li, Y. J., An, H. P., C., Greeshma, Chang, J. P., Chen, Y. H., Cheng, J. P., Dai, W. H., Deng, Z., Fang, C. H., Gong, H., Guo, Q. J., Guo, T., Guo, X. Y., He, L., He, S. M., Hu, J. W., Huang, H. X., Huang, T. C., Jiang, L., Karmakar, S., Li, H. B., Li, H. Y., Li, J. M., Li, J., Li, Q. Y., Li, R. M. J., Li, X. Q., Li, Y. L., Liang, Y. F., Liao, B., Lin, F. K., Lin, S. T., Liu, J. X., Liu, S. K., Liu, Y. D., Liu, Y., Liu, Y. Y., Ma, H., Mao, Y. C., Nie, Q. Y., Ning, J. H., Pan, H., Qi, N. C., Ren, J., Ruan, X. C., Singh, M. K., Sun, T. X., Tang, C. J., Tian, Y., Wang, G. F., Wang, J. Z., Wang, L., Wang, Q., Wang, Y. F., Wang, Y. X., Wong, H. T., Wu, S. Y., Wu, Y. C., Xing, H. Y., Xu, R., Xu, Y., Xue, T., Yan, Y. L., Yi, N., Yu, C. X., Yu, H. J., Yue, J. F., Zeng, M., Zeng, Z., Zhang, B. T., Zhang, F. S., Zhang, L., Zhang, Z. H., Zhang, Z. Y., Zhao, J. Z., Zhao, K. K., Zhao, M. G., Zhou, J. F., Zhou, Z. Y., and Zhu, J. J.

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

CDEX-50 is a next-generation project of the China Dark Matter Experiment (CDEX) that aims to search for dark matter using a 50-kg germanium detector array. This paper comprises a thorough summary of the CDEX-50 dark matter experiment, including an investigation of potential background sources and the development of a background model. Based on the baseline model, the projected sensitivity of weakly interacting massive particle (WIMP) is also presented. The expected background level within the energy region of interest, set to 2--2.5 keVee, is $\sim$0.01 counts keVee$^{-1}$ kg$^{-1}$ day$^{-1}$. At 90\% confidence level, the expected sensitivity to spin-independent WIMP-nucleon couplings is estimated to reach a cross-section of 5.1 $\times$ 10$^{-45}$ cm$^{2}$ for a WIMP mass of 5 GeV/c$^{2}$ with an exposure objective of 150 kg$\cdot$year and an analysis threshold of 160 eVee. This science goal will correspond to the most sensitive results for WIMPs with a mass of 2.2--8 GeV/c$^{2}$., Comment: 12 pages, 11 figures. Version updated to match JCAP version

Published
2023
Full Text
View/download PDF

16. Measurement and analysis of 155,157Gd(n,γ) from thermal energy to 1 keV

Author

Massimi C., Aberle O., Andrzejewski J., Audouin L., Bacak M., Balibrea J., Barbagallo M., Bečvář F., Berthoumieux E., Billowes J., Bosnar D., Brown A., Caamaño M., Calviño F., Calviani M., Cano-Ott D, Cardella R., Casanovas A., Castelluccio D. M., Cerutti F., Chen Y. H., Chiaveri E., Clai G., Colonna N., Console Camprini P., Cortés G., Cortés-Giraldo M. A., Cosentino L., Damone L. A., Diakaki M., Domingo-Pardo C, Dressler R., Dupont E., Durán I., Fernández-Domínguez B., Ferrari A., Ferreira P., Finocchiaro P., Furman V., Göbel K., García A. R., Gawlik A., Gilardoni S., Glodariu T., Gonçalves I. F., González-Romero E., Griesmayer E., Guerrero C., Guglielmelli A., Gunsing F., Harada H., Heinitz S., Heyse J., Jenkins D. G., Jericha E., Käppeler F., Kadi Y., Kalamara A., Kavrigin P., Kimura A., Kivel N., Knapova I., Kokkoris M., Krtička M., Kurtulgil D., Leal-Cidoncha E, Lederer C., Leeb H., Lerendegui-Marco J, Lonsdale S. J., Macina D., Manna A., Marganiec J., Martínez T., Masi A., Mastinu P., Mastromarco M., Maugeri E. A., Mazzone A., Mendoza E., Mengoni A., Milazzo P. M., Mingrone F., Mucciola R., Musumarra A., Negret A., Nolte R., Oprea A., Patronis N., Pavlik A., Perkowski J., Porras I., Praena J., Quesada J. M., Radeck D., Rauscher T., Reifarth R., Rocchi F., Rubbia C., Ryan J. A., Sabaté-Gilarte M., Saxena A., Schillebeeckx P., Schumann D., Sedyshev P., Smith A. G., Sosnin N. V., Stamatopoulos A., Tagliente G., Tain J. L, Tarifeño-Saldivia A., Tassan-Got L, Valenta S., Vannini G., Variale V., Vaz P., Ventura A., Vlachoudis V., Vlastou R., Wallner A., Warren S., Weiss C., Woods P. J., Wright T., and Žugec P.

Subjects
Physics, QC1-999
Abstract

We have measured the capture cross section of the 155Gd and 157Gd isotopes between 0.025 eV and 1 keV. The capture events were recorded by an array of 4 C6D6 detectors, and the capture yield was deduced exploiting the total energy detection system in combination with the Pulse Height Weighting Techniques. Because of the large cross section around thermal neutron energy, 4 metallic samples of different thickness were used to prevent problems related to self-shielding. The samples were isotopically enriched, with a cross contamination of the other isotope of less than 1.14%. The capture yield was analyzed with an R-Matrix code to describe the cross section in terms of resonance parameters. Near thermal energies, the results are significantly different from evaluations and from previous time-of-flight experiments. The data from the present measurement at n_TOF are publicly available in the experimental nuclear reaction database EXFOR.

Published
2020
Full Text
View/download PDF

17. Accurate measurement of the standard 235U(n,f) cross section from thermal to 170 keV neutron energy

Author

Amaducci S., Aberle O., Andrzejewski J., Audouin L., Bacak M., Balibrea J., Barbagallo M., Bečvář F., Berthoumieux E., Billowes J., Bosnar D., Brown A., Caamaño M., Calviño F., Calviani M., Cano-Ott D, Cardella R., Casanovas A., Cerutti F., Chen Y. H., Chiaveri E., Colonna N., Cortés G., Cortés-Girardo M. A., Cosentino L., Damone L. A., Diakaki M., Domingo-Pardo C, Dressler R., Dupont E., Durán I., Fernández-Domínguez B., Ferrari A., Ferreira P., Finocchiaro P., Furman V., Göbel K., García A. R., Gawlik A., Gilardoni S., Glodariu T., Gonçalves I. F., González-Romero E., Griesmayer E., Guerrero C., Gunsing F., Harada H., Heinitz S., Heyse J., Jenkins D. G., Jericha E., Käppeler F., Kadi Y., Kalamara A., Kavrigin P., Kimura A., Kivel N., Knapova I., Kokkoris M., Krtička M., Kurtulgil D., Leal-Cidoncha E, Lederer C., Leeb H., Lerendegui-Marco J, Lo Meo S., Lonsdale S. J., Macina D., Manna A., Marganiec J., Martínez T., Masi A., Massimi C., Mastinu P., Mastromarco M., Maugeri E. A., Mazzone A., Mendoza E., Mengoni A., Milazzo P. M., Mingrone F., Musumarra A., Negret A., Nolte R., Oprea A., Patronis N., Pavlik A., Perkowski J., Porras I., Praena J., Quesada J. M., Radeck D., Rauscher T., Reifarth R., Rubbia C., Ryan J. A., Sabaté-Gilarte M., Saxena A., Schillebeeckx P., Schumann D., Sedyshev P., Smith A. G., Sosnin N. V., Stamatopoulos A., Tagliente G., Tain J. L., Tarifeño-Saldivia A., Tassan-Got L, Valenta S., Vannini G., Variale V., Vaz P., Ventura A., Vlachoudis V., Vlastou R., Wallner A., Warren S., Weiss C., Woods P. J., Wright T., and Žugec P.

Subjects
Physics, QC1-999
Abstract

An accurate measurement of the 235U(n,f) cross section from thermal to 170 keV of neutron energy has recently been performed at n_TOF facility at CERN using 6Li(n,t)4He and 10B(n,α)7Li as references. This measurement has been carried out in order to investigate a possible overestimation of the 235U fission cross section evaluation provided by most recent libraries between 10 and 30 keV. A custom experimental apparatus based on in-beam silicon detectors has been used, and a Monte Carlo simulation in GEANT4 has been employed to characterize the setup and calculate detectors efficiency. The results evidenced the presence of an overestimation in the interval between 9 and 18 keV and the new data may be used to decrease the uncertainty of 235U(n,f) cross section in the keV region.

Published
2020
Full Text
View/download PDF

18. Study of the neutron-induced fission cross section of 237Np at CERN's n_TOF facility over a wide energy range

Author

Stamatopoulos A., Tsinganis A., Diakaki M., Colonna N., Kokkoris M., Vlastou R., Kalamara A., Schillebeeckx P., Tassan-Got L, Žugec P., Sabaté-Gilarte M., Patronis N., Eleme Z., Heyse J., Aberle O., Andrzejewski J., Audouin L., Bacak M., Balibrea J., Barbagallo M., Bečvář F., Berthoumieux E., Billowes J., Bosnar D., Brown A., Caamaño M., Calviño F., Calviani M., Cano-Ott D, Cardella R., Casanovas A., Cerutti F., Chen Y. H., Chiaveri E., Cortés G., Cortés-Giraldo M. A., Cosentino L., Damone L. A., Domingo-Pardo C, Dressler R., Dupont E., Durán, Femandez-Domínguez B., Ferrari A., Ferreira P., Finocchiaro P., Furman V., Göbel K., García A. R., Gawlik A., Gilardoni S., Glodariu† T., Gonçalves I. F., González-Romero E., Griesmayer E., Guerrero C., Gunsing F., Harada H., Heinitz S., Jenkins D. G., Jericha E., Käppeler F., Kadi Y., Kavrigin P., Kimura A., Kivel N., Knapova I., Krtička M., Kurtulgil D., Leal-Cidoncha E, Lederer C., Leeb H., Lerendegui-Marco J, Meo S. Lo, Lonsdale S. J., Macina D., Manna A., Marganiec J., Martínez T., Masi A., Massimi C., Mastinu P., Mastromarco M., Maugeri E. A., Mazzone A., Mendoza E., Mengoni A., Milazzo P. M., Mingrone F., Musumarra A., Negret A., Nolte R., Oprea A., Pavlik A., Perkowski J., Porras I., Praena J., Quesada J. M., Radeck D., Rauscher T., Reifarth R., Rubbia C., Ryan J. A., Saxena A., Schumann D., Sedyshev P., Smith A. G., Sosnin N. V., Tagliente G., Tain J. L., Tarifeño-Saldivia A., Valenta S., Vannini G., Variale V., Vaz P., Ventura A., Vescovi D., Vlachoudis V., Wallner A., Warren S., Weiss C., Woods P. J., and Wright T.

Subjects
Physics, QC1-999
Abstract

Neutron-induced fission cross sections of isotopes involved in the nuclear fuel cycle are vital for the design and safe operation of advanced nuclear systems. Such experimental data can also provide additional constraints for the adjustment of nuclear model parameters used in the evaluation process, resulting in the further development of fission models. In the present work, the 237Np(n,f) cross section was studied at the EAR2 vertical beam-line at CERN's n_TOF facility, over a wide range of neutron energies, from meV to MeV, using the time-of-flight technique and a set-up based on Micromegas detectors, in an attempt to provide accurate experimental data. Preliminary results in the 200 keV – 14 MeV neutron energy range as well as the experimental procedure, including a description of the facility and the data handling and analysis, will be presented.

Published
2020
Full Text
View/download PDF

19. Preliminary results on the 233U α-ratio measurement at n_TOF

Author

Bacak M., Aïche M., Bélier G., Berthoumieux E., Diakaki M., Dupont E., Gunsing F., Heyse J., Kopecky S., Krtička M., Laurent B., Leeb H., Mathieu L., Schillebeeckx P., Serot O., Taieb J., Valenta S., Vlachoudis V., Aberle O., Andrzejewski J., Audouin L., Balibrea J., Barbagallo M., Bečvář F., Billowes J., Bosnar D., Brown A., Caamaño M., Calviño F., Calviani, Cano-Ott D, Cardella R., Casanovas A., Cerutti F., Chen Y. H., Chiaveri E., Colonna, Cortés G., Cortés-Giraldo M. A., Cosentino L., Damone L. A., Domingo-Pardo C, Dressler R., Durán I., Fernández-Domínguez B., Ferrari A., Ferreira P., Finocchiaro P., Furman V., Göbel K., García A. R., Gawlik A., Gilardoni S., Glodariu T., Gonçalves I. F., González-Romero E., Griesmayer E., Guerrero C., Harada H., Heinitz S., Jenkins D. G., Jericha E., Käppeler F., Kadi Y., Kalamara A., Kavrigin P., Kimura A., Kivel N., Knapova I., Kokkoris M., Kurtulgil D., Leal-Cidoncha E, Lederer C., Lerendegui-Marco J, Meo S. Lo, Lonsdale S. J., Macina D., Manna A., Marganiec J., Martínez T., Masi A., Massimi C., Mastinu P., Mastromarco M., Maugeri E. A., Mazzone A., Mendoza E., Mengoni A., Milazzo P. M., Mingrone F., Musumarra A., Negret A., Nolte R., Oprea A., Patronis N., Pavlik A., Perkowski J., Porras I., Praena J., Quesada J. M., Radeck D., Rauscher T., Reifarth R., Rubbia C., Ryan J. A., Sabaté-Gilarte M., Saxena A., Schumann D., Sedyshev P., Smith A. G., Sosnin N. V., Stamatopoulos A., Tagliente G., Tain J. L., Tarifeño-Saldivia A., Tassan-Got L, Vannini G., Variale V., Vaz P., Ventura A., Vlastou R., Wallner A., Warren S., Weiss C., Woods P. J., Wright T., and Žugec P.

Subjects
Physics, QC1-999
Abstract

233U is the fissile nuclei in the Th-U fuel cycle with a particularily small neutron capture cross setion which is on average about one order of magnitude lower than its fission cross section. Hence, the measurement of the 233U(n, γ) cross section relies on a method to accurately distinguish between capture and fission γ-rays. A measurement of the 233U α-ratio has been performed at the n_TOF facility at CERN using a so-called fission tagging setup, coupling n_TOF 's Total Absorption Calorimeter with a novel fission chamber to tag the fission γ-rays. The experimental setup is described and essential parts of the analysis are discussed. Finally, a preliminary 233U α-ratio is presented.

Published
2020
Full Text
View/download PDF

20. Neutron capture cross section measurements of 241Am at the n_TOF facility

Author

Oprea A., Gunsing F., Schillebeeckx P., Aberle O., Bacak M., Berthoumieux E., Cano-Ott D, Diakaki M., Dupont E., Geslot B., Glodariu T., Heyse J., Mendoza E., Negret A., Alcayne V., Amaducci S., Andrzejewski J., Audouin L., Bécares V., Babiano-Suarez V, Barbagallo M., Becčvář F., Bellia G., Billowes J., Bosnar D., Brown A., Busso M., Caamaño M., Caballero-Ontanaya L, Calviño F., Calviani M., Casanovas A., Cerutti F., Chen Y. H., Chiaveri E., Colonna N., Cortés G., Cortés-Giraldo M. A., Cosentino L., Cristallo S., Damone L. A., Dietz M., Domingo-Pardo C, Dressler R., Durán I., Eleme Z., Femández-Domínguez B., Ferrari A., Finocchiaro P., Furman V., Göbel K., Garg R., Gawlik A., Gilardoni S., Goncalves I. F., González-Romero E., Guerrero C., Harada H., Heinitz S., Jenkins D. G., Jericha E., Käppeler F., Kadi Y., Kimura A., Kivel N., Kokkoris M., Kopatch Y., Krtička M., Kurtulgil D., Ladarescu I., Lederer-Woods C, Lerendegui-Marco J, Meo S. Lo, Lonsdale S. J., Macina D., Manna A., Martínez T., Masi A., Massimi C., Mastinu P., Mastromarco M., Matteucci F., Maugeri E. A., Mazzone A., Mengoni A., Michalopoulou V., Milazzo P. M., Mingrone F., Musumarra A., Nolte R., Ogállar F., Patronis N., Pavlik A., Perkowski J., Persanti L., Porras I., Praena J., Quesada J. M., Radeck D., Ramos-Doval D, Reifarth R., Rochman D., Rubbia C., Sabaté-Gilarte M., Saxena A., Schumann D., Smith A. G., Sosnin N. V., Stamatopoulos A., Tagliente G., Tain J. L., Talip T., Tarifeño-Saldivia A., Tassan-Got L, Torres-Sánchez P., Tsinganis A., Ulrich J., Urlass S., Valenta S., Vannini G., Variale V., Vaz P., Ventura A., Vlachoudis V., Vlastou R., Wallner A., Woods P. J., Wright T., and Žugec P.

Subjects
Physics, QC1-999
Abstract

Neutron capture on 241Am plays an important role in the nuclear energy production and also provides valuable information for the improvement of nuclear models and the statistical interpretation of the nuclear properties. A new experiment to measure the 241Am(n, γ) cross section in the thermal region and the first few resonances below 10 eV has been carried out at EAR2 of the n_TOF facility at CERN. Three neutron-insensitive C6D6 detectors have been used to measure the neutron-capture gamma cascade as a function of the neutron time of flight, and then deduce the neutron capture yield. Preliminary results will be presented and compared with previously obtained results at the same facility in EAR1. In EAR1 the gamma-ray background at thermal energies was about 90% of the signal while in EAR2 is up to a 25 factor much more favorable signal to noise ratio. We also extended the low energy limit down to subthermal energies. This measurement will allow a comparison with neutron capture measurements conducted at reactors and using a different experimental technique.

Published
2020
Full Text
View/download PDF

21. Measurement of the 244Cm capture cross sections at both CERN n_TOF experimental areas

Author

Alcayne V., Mendoza E., Cano-Ott D, Kimura A., Aberle O., Amaducci S., Andrzejewski J., Audouin L., Babiano-Suarez V, Bacak M., Barbagallo M., Bécares V., Bečvář F., Bellia G., Berthoumieux E., Billowes J., Bosnar D., Brown A. S., Busso M., Caamaño M., Caballero L., Calviani M., Calviño F., Casanovas A., Cerutti F., Chen Y. H., Chiaveri E., Colonna N., Cortés G. P., Cortés-Giraldo M. A., Cosentino L., Cristallo S., Damone L. A., Diakaki M., Dietz M., Domingo-Pardo C, Dressler R., Dupont E., Durán I., Eleme Z., Fernández-Domíngez B., Ferrari A., Ferro-Gonçalves I., Finocchiaro P., Furman V., Garg R., Gawlik A., Gilardoni S., Glodariu T., Göbel K., González-Romero E., Guerrero C., Gunsing F., Heinitz S., Heyse J., Jenkins D. G., Jericha E., Kadi Y., Käppeler F., Kivel N., Kokkoris M., Kopatch Y., Krtička M., Kurtulgil D., Ladarescu I., Lederer-Woods C, Lerendegui-Marco J, Lo Meo S., Lonsdale S.-J., Macina D., Manna A., Martínez T., Masi A., Massimi C., Mastinu P. F., Mastromarco M., Matteucci F., Maugeri E., Mazzone A., Mengoni A., Michalopoulou V., Milazzo P. M., Mingrone F., Musumarra A., Negret A., Nolte R., Ogállar F., Oprea A., Patronis N., Pavlik A., Perkowski J., Piersanti L., Porras I., Praena J., Quesada J. M., Radeck D., Ramos Doval D., Reifarth R., Rochman D., Rubbia C., Sabaté-Gilarte M., Saxena A., Schillebeeckx P., Schumann D., Smith A. G., Sosnin N., Stamatopoulos A., Tagliente G., Tain J. L., Talip Z., Tarifeño-Saldivia A. E., Tassan-Got L, Torres-Sánchez P., Tsinganis A., Ulrich J., Urlass S., Valenta S., Vannini G., Variale V., Vaz P., Ventura A., Vlachoudis V., Vlastou R., Wallner A., Woods P. J., Wright T. J., and Žugec P.

Subjects
Physics, QC1-999
Abstract

Accurate neutron capture cross section data for minor actinides (MAs) are required to estimate the production and transmutation rates of MAs in light water reactors with a high burnup, critical fast reactors like Gen-IV systems and other innovative reactor systems such as accelerator driven systems (ADS). Capture reactions of 244Cm open the path for the formation of heavier Cm isotopes and of heavier elements such as Bk and Cf. In addition, 244Cm shares nearly 50% of the total actinide decay heat in irradiated reactor fuels with a high burnup, even after three years of cooling. Experimental data for this isotope are very scarce due to the difficulties of providing isotopically enriched samples and because the high intrinsic activity of the samples requires the use of neutron facilities with high instantaneous flux. The only two previous experimental data sets for this neutron capture cross section have been obtained in 1969 using a nuclear explosion and, more recently, at J-PARC in 2010. The neutron capture cross sections have been measured at n_TOF with the same samples that the previous experiments in J-PARC. The samples were measured at n_TOF Experimental Area 2 (EAR-2) with three C6D6 detectors and also in Experimental Area 1 (EAR-1) with the Total Absorption Calorimeter (TAC). Preliminary results assessing the quality and limitations of these new experimental datasets are presented for the experiments in both areas. Preliminary yields of both measurements will be compared with evaluated libraries for the first time.

Published
2020
Full Text
View/download PDF

22. Measurement of the 242Pu(n, γ) cross section from thermal to 500 keV at the Budapest research reactor and CERN n_TOF-EAR1 facilities

Author

Lerendegui-Marco J, Guerrero C., Mendoza E., Quesada J. M., Eberhardt K., Junghans A., Krtiička M., Belgya T., Maróti B., Aberle O., Andrzejewski J., Audouin L., Bécares V., Bacak M., Balibrea J., Barbagallo M., Barros S., Bečvář F., Beinrucker C., Berthoumieux E., Billowes J., Bosnar D., Brugger M., Caamaño M., Calviño F., Calviani M., Cano-Ott D, Cardella R., Casanovas A., Castelluccio D. M., Cerutti F., Chen Y. H., Chiaveri E., Colonna N., Cortés G., Cortés-Giraldo M. A., Cosentino L., Damone L. A., Diakaki M., Domingo-Pardo C, Dressler R., Dupont E., Durán I., Fernández-Domínguez B., Ferrari A., Ferreira P., Finocchiaro P., Furman V., Göbel K., García A. R., Gawlik A., Glodariu T., Gonçalves I. F., González-Romero E., Goverdovski A., Griesmayer E., Gunsing F., Harada H., Heftrich T., Heinitz S., Heyse J., Jenkins D. G., Jericha E., Käppeler F., Kadi Y., Katabuchi T., Kavrigin P., Ketlerov V., Khryachkov V., Kimura A., Kivel N., Knapova I., Kokkoris M., Leal-Cidoncha E, Lederer C., Leeb H., Lo Meo S., Lonsdale S. J., Losito R., Macina D., Marganiec J., Martínez T., Massimi C., Mastinu P., Mastromarco M., Matteucci F., Maugeri E. A., Mengoni A., Milazzo P. M., Mingrone F., Mirea M., Montesano S., Musumarra A., Nolte R., Oprea A., Patronis N., Pavlik A., Perkowski J., Porras J. I., Praena J., Rajeev K., Rauscher T., Reifarth R., Riego-Perez A, Rout P. C., Rubbia C., Ryan J. A., Sabaté-Gilarte M., Saxena A., Schillebeeckx P., Schmidt S., Schumann D., Sedyshev P., Smith A. G., Stamatopoulos A., Tagliente G., Tain J. L., Tarifeño-Saldivia A., Tassan-Got L, Tsinganis A., Valenta S., Vannini G., Variale V., Vaz P., Ventura A., Vescovi D., Vlachoudis V., Vlastou R., Wallner A., Warren S., Weigand M., Weiss C., Wolf C., Woods P. J., Wright T., and Žugec P.

Subjects
Physics, QC1-999
Abstract

The design and operation of innovative nuclear systems requires a better knowledge of the capture and fission cross sections of the Pu isotopes. For the case of capture on 242Pu, a reduction of the uncertainty in the fast region down to 8-12% is required. Moreover, aiming at improving the evaluation of the fast energy range in terms of average parameters, the OECD NEA High Priority Request List (HPRL) requests high-resolution capture measurements with improved accuracy below 2 keV. The current uncertainties also affect the thermal point, where previous experiments deviate from each other by 20%. A fruitful collaboration betwen JGU Mainz and HZ Dresden-Rossendorf within the EC CHANDA project resulted in a 242Pu sample consisting of a stack of seven fission-like targets making a total of 95(4) mg of 242Pu electrodeposited on thin (11.5 μm) aluminum backings. This contribution presents the results of a set of measurements of the 242Pu(n, γ) cross section from thermal to 500 keV combining different neutron beams and techniques. The thermal point was determined at the Budapest Research Reactor by means of Neutron Activation Analysis and Prompt Gamma Analysis, and the resolved (1 eV - 4 keV) and unresolved (1 - 500 keV) resonance regions were measured using a set of four Total Energy detectors at the CERN n_TOF-EAR1.

Published
2020
Full Text
View/download PDF

23. Study of photon strength functions of 241Pu and 245Cm from neutron capture measurements

Author

Mendoza E., Alcayne V., Cano-Ott D, Kimura A., Skarbeli A. V., Aberle O., Amaducci S., Andrzejewski J., Audouin L., Babiano-Suarez V, Bacak M., Barbagallo M., Bécares V., Bečvář F., Bellia G., Berthoumieux E., Billowes J., Bosnar D., Brown A. S., Busso M., Caamaño M., Caballero L., Calviani M., Calviño F., Casanovas A., Cerutti F., Chen Y. H., Chiaveri E., Colonna N., Cortés G. P., Cortés-Giraldo M. A., Cosentino L., Cristallo S., Damone L. A., Diakaki M., Dietz M., Domingo-Pardo C, Dressler R., Dupont E., Durán I., Eleme Z., Fernández-Domíngez B., Ferrari A., Ferro-Gonçalves I., Finocchiaro P., Furman V., Garg R., Gawlik A., Gilardoni S., Glodariu T., Göbel K., González-Romero E., Guerrero C., Gunsing F., Heinitz S., Heyse J., Jenkins D. G., Jericha E., Kadi Y., Käppeler F., Kivel N., Kokkoris M., Kopatch Y., Krtička M., Kurtulgil D., Ladarescu I., Lederer-Woods C, Lerendegui-Marco J, Meo S. Lo, Lonsdale S.-J., Macina D., Manna A., Martínez T., Masi A., Massimi C., Mastinu P. F., Mastromarco M., Matteucci F., Maugeri E., Mazzone A., Mengoni A., Michalopoulou V., Milazzo P. M., Mingrone F., Musumarra A., Negret A., Nolte R., Ogállar F., Oprea A., Patronis N., Pavlik A., Perkowski J., Piersanti L., Porras I., Praena J., Quesada J. M., Radeck D., Doval D. Ramos, Reifarth R., Rochman D., Rubbia C., Sabaté-Gilarte M., Saxena A., Schillebeeckx P., Schumann D., Smith A. G., Sosnin N., Stamatopoulos A., Tagliente G., Tain J. L., Talip Z., Tarifeño-Saldivia A. E., Tassan-Got L, Torres-Sánchez P., Tsinganis A., Ulrich J., Urlass S., Valenta S., Vannini G., Variale V., Vaz P., Ventura A., Vlachoudis V., Vlastou R., Wallner A., Woods P. J., Wright T. J., and Žugec P.

Subjects
Physics, QC1-999
Abstract

We have measured the γ-rays following neutron capture on 240Pu and 244 Cm at the n_TOF facility at CERN with the Total Absorption Calorimeter (TAC) and with C6D6 organic scintillators. The TAC is made of 40 BaF2 crystals operating in coincidence and covering almost the entire solid angle. This allows to obtain information concerning the energy spectra and the multiplicity of the measured capture γ-ray cascades. Additional information is also obtained from the C6D6 detectors. We have analyzed the measured data in order to draw conclusions about the Photon Strength Functions (PSFs) of 241Pu and 245Cm below their neutron separation energies. The analysis has been performed by fitting the PSFs to the experimental results, using the differential evolution method, in order to find neutron capture cascades capable of reproducing at the same time a great variety of deposited energy spectra.

Published
2020
Full Text
View/download PDF

24. An initial analysis of a strongly-lensed QSOs candidate identified by LAMOST

Author

Chen, Y. H., Tang, M. Y., Shu, H., and Tu, H.

Subjects
Astrophysics - Astrophysics of Galaxies
Abstract

From 2011 to 2021, LAMOST has released a total of 76,167 quasar data. We try to search for gravitationally lensed QSOs by limiting coordinate differences and redshift differences of these QSOs. The name, brightness, spectrum, photometry and other information of each QSO will be visually checked carefully. Special attention should be paid to check whether there are groups of galaxies, gravitationally lensed arcs, Einstein crosses, or Einstein rings near the QSOs. Through careful selection, we select LAMOST J160603.01+290050.8 (A) and LAMOST J160602.81+290048.7 (B) as a candidate and perform an initial analysis. The component A and B are 3.36 arc seconds apart and they display blue during photometric observations. The redshift values of component A and B are 0.2\% different, their Gaia$\_$g values are 1.3\% different, and their ugriz values are 1.0\% or less different. For the spectra covering from 3,690 {\AA} to 9,100 {\AA}, the emission lines of C\,II, Mg, H\,$\gamma$, O\,III, and H\,$\beta$ are present for both component A and B and the ratio of flux(B) to flux(A) from LAMOST is basically a constant, around 2.2. We accidentally find a galaxy group near the component A and B. If the center of dark matter in the galaxy group is at the center between component A and B, the component A and B are probably gravitationally lensed QSOs. We estimate that the Einstein mass is 1.46 $\times$ $10^{11}$ $M_{\odot}$ and the total mass of the lens is 1.34 $\times$ $10^{13}$ $M_{\odot}$. The deflection angle is 1.97 arc seconds at positions A and B and the velocity dispersion is 261\,$km\,s^{-1}$. Theoretically, this candidate could be a pair of fold images of a strong lensing system by a galaxy group, and we will investigate the possibility when the redshifts of nearby galaxies are available., Comment: 2 tables and 4 figures, accepted by RAA on August 24, 2023

Published
2023

25. The Lobster Eye Imager for Astronomy Onboard the SATech-01 Satellite

Author

Ling, Z. X., Sun, X. J., Zhang, C., Sun, S. L., Jin, G., Zhang, S. N., Zhang, X. F., Chang, J. B., Chen, F. S., Chen, Y. F., Cheng, Z. W., Fu, W., Han, Y. X., Li, H., Li, J. F., Li, Y., Li, Z. D., Liu, P. R., Lv, Y. H., Ma, X. H., Tang, Y. J., Wang, C. B., Xie, R. J., Xue, Y. L., Yan, A. L., Zhang, Q., Bao, C. Y., Cai, H. B., Cheng, H. Q., Cui, C. Z., Dai, Y. F., Fan, D. W., Hu, H. B., Hu, J. W., Huang, M. H., Jia, Z. Q., Jin, C. C., Li, D. Y., Li, J. Q., Liu, H. Y., Liu, M. J., Liu, Y., Pan, H. W., Qiu, Y. L., Sugizaki, M., Sun, H., Wang, W. X., Wang, Y. L., Wu, Q. Y., Xu, X. P., Xu, Y. F., Yang, H. N., Yang, X., Zhang, B., Zhang, M., Zhang, W. D., Zhang, Z., Zhao, D. H., Cong, X. Q., Jiang, B. W., Li, L. H., Qiu, X. B., Sun, J. N., Su, D. T., Wang, J., Wu, C., Xu, Z., Yang, X. M., Zhang, S. K., Zhang, N., Zhu, Y. F., Ban, H. Y., Bi, X. Z., Cai, Z. M., Chen, W., Chen, X., Chen, Y. H., Cui, Y., Duan, X. L., Feng, Z. G, Gao, Y., He, J. W., He, T., Huang, J. J., Li, F., Li, J. S., Li, T. J., Li, T. T., Liu, H. Q., Liu, L., Liu, R., Liu, S., Meng, N., Shi, Q., Sun, A. T., Wang, Y. M., Wang, Y. B., Wu, H. C., Xu, D. X, Yang, Y. Q, Yang, Y., Yu, X. S., Zhang, K. X., Zhang, Y. L., Zhang, Y. H., Zhang, Y. T., Zhou, H., Zhu, X. C., Cheng, J. S., Qin, L., Wang, L., Wang, Q. L., Bai, M., Gao, R. L., Ji, Z., Liu, Y. R., Ma, F. L., Shi, Y. J., Su, J., Tan, Y. Y., Tong, J. Z., Xu, H. T., Xue, C. B., Xue, G. F., and Yuan, W.

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

The Lobster Eye Imager for Astronomy (LEIA), a pathfinder of the Wide-field X-ray Telescope of the Einstein Probe (EP) mission, was successfully launched onboard the SATech-01 satellite of the Chinese Academy of Sciences on 27 July 2022. In this paper, we introduce the design and on-ground test results of the LEIA instrument. Using state-of-the-art Micro-Pore Optics (MPO), a wide field-of-view (FoV) of 346 square degrees (18.6 degrees * 18.6 degrees) of the X-ray imager is realized. An optical assembly composed of 36 MPO chips is used to focus incident X-ray photons, and four large-format complementary metal-oxide semiconductor (CMOS) sensors, each of 6 cm * 6 cm, are used as the focal plane detectors. The instrument has an angular resolution of 4 - 8 arcmin (in FWHM) for the central focal spot of the point spread function, and an effective area of 2 - 3 cm2 at 1 keV in essentially all the directions within the field of view. The detection passband is 0.5 - 4 keV in the soft X-rays and the sensitivity is 2 - 3 * 10-11 erg s-1 cm-2 (about 1 mini-Crab) at 1,000 second observation. The total weight of LEIA is 56 kg and the power is 85 W. The satellite, with a design lifetime of 2 years, operates in a Sun-synchronous orbit of 500 km with an orbital period of 95 minutes. LEIA is paving the way for future missions by verifying in flight the technologies of both novel focusing imaging optics and CMOS sensors for X-ray observation, and by optimizing the working setups of the instrumental parameters. In addition, LEIA is able to carry out scientific observations to find new transients and to monitor known sources in the soft X-ray band, albeit limited useful observing time available., Comment: Accepted by RAA

Published
2023
Full Text
View/download PDF

26. Some Separable integer partition classes

Author

Chen, Y. H., He, Thomas Y., Tang, F., and Wei, J. J.

Subjects
Mathematics - Combinatorics
Abstract

Recently, Andrews introduced separable integer partition classes and analyzed some well-known theorems. In this paper, we investigate partitions with parts separated by parity introduced by Andrews with the aid of separable integer partition classes with modulus $2$. We also extend separable integer partition classes with modulus $1$ to overpartitions, called separable overpartition classes. We study overpartitions and the overpartition analogue of Rogers-Ramanujan identities, which are separable overpartition classes.

Published
2023

27. A Race Track Trapped-Ion Quantum Processor

Author

Moses, S. A., Baldwin, C. H., Allman, M. S., Ancona, R., Ascarrunz, L., Barnes, C., Bartolotta, J., Bjork, B., Blanchard, P., Bohn, M., Bohnet, J. G., Brown, N. C., Burdick, N. Q., Burton, W. C., Campbell, S. L., Campora III, J. P., Carron, C., Chambers, J., Chan, J. W., Chen, Y. H., Chernoguzov, A., Chertkov, E., Colina, J., Curtis, J. P., Daniel, R., DeCross, M., Deen, D., Delaney, C., Dreiling, J. M., Ertsgaard, C. T., Esposito, J., Estey, B., Fabrikant, M., Figgatt, C., Foltz, C., Foss-Feig, M., Francois, D., Gaebler, J. P., Gatterman, T. M., Gilbreth, C. N., Giles, J., Glynn, E., Hall, A., Hankin, A. M., Hansen, A., Hayes, D., Higashi, B., Hoffman, I. M., Horning, B., Hout, J. J., Jacobs, R., Johansen, J., Jones, L., Karcz, J., Klein, T., Lauria, P., Lee, P., Liefer, D., Lytle, C., Lu, S. T., Lucchetti, D., Malm, A., Matheny, M., Mathewson, B., Mayer, K., Miller, D. B., Mills, M., Neyenhuis, B., Nugent, L., Olson, S., Parks, J., Price, G. N., Price, Z., Pugh, M., Ransford, A., Reed, A. P., Roman, C., Rowe, M., Ryan-Anderson, C., Sanders, S., Sedlacek, J., Shevchuk, P., Siegfried, P., Skripka, T., Spaun, B., Sprenkle, R. T., Stutz, R. P., Swallows, M., Tobey, R. I., Tran, A., Tran, T., Vogt, E., Volin, C., Walker, J., Zolot, A. M., and Pino, J. M.

Subjects
Quantum Physics
Abstract

We describe and benchmark a new quantum charge-coupled device (QCCD) trapped-ion quantum computer based on a linear trap with periodic boundary conditions, which resembles a race track. The new system successfully incorporates several technologies crucial to future scalability, including electrode broadcasting, multi-layer RF routing, and magneto-optical trap (MOT) loading, while maintaining, and in some cases exceeding, the gate fidelities of previous QCCD systems. The system is initially operated with 32 qubits, but future upgrades will allow for more. We benchmark the performance of primitive operations, including an average state preparation and measurement error of 1.6(1)$\times 10^{-3}$, an average single-qubit gate infidelity of $2.5(3)\times 10^{-5}$, and an average two-qubit gate infidelity of $1.84(5)\times 10^{-3}$. The system-level performance of the quantum processor is assessed with mirror benchmarking, linear cross-entropy benchmarking, a quantum volume measurement of $\mathrm{QV}=2^{16}$, and the creation of 32-qubit entanglement in a GHZ state. We also tested application benchmarks including Hamiltonian simulation, QAOA, error correction on a repetition code, and dynamics simulations using qubit reuse. We also discuss future upgrades to the new system aimed at adding more qubits and capabilities., Comment: 24 pages, 24 figures. Made some minor edits and added several more authors

Published
2023
Full Text
View/download PDF

28. Searching for $^{76}$Ge neutrinoless double beta decay with the CDEX-1B experiment

Author

Zhang, B. T., Wang, J. Z., Yang, L. T., Yue, Q., Kang, K. J., Li, Y. J., An, H. P., C., Greeshma, Chang, J. P., Chen, Y. H., Cheng, J. P., Dai, W. H., Deng, Z., Fang, C. H., Geng, X. P., Gong, H., Guo, Q. J., Guo, X. Y., He, L., He, S. M., Hu, J. W., Huang, H. X., Huang, T. C., Jia, H. T., Jiang, X., Karmakar, S., Li, H. B., Li, J. M., Li, J., Li, Q. Y., Li, R. M. J., Li, X. Q., Li, Y. L., Liang, Y. F., Liao, B., Lin, F. K., Lin, S. T., Liu, J. X., Liu, S. K., Liu, Y. D., Liu, Y., Liu, Y. Y., Liu, Z. Z., Ma, H., Mao, Y. C., Nie, Q. Y., Ning, J. H., Pan, H., Qi, N. C., Ren, J., Ruan, X. C., She, Z., Singh, M. K., Sun, T. X., Tang, C. J., Tang, W. Y., Tian, Y., Wang, G. F., Wang, L., Wang, Q., Wang, Y. F., Wang, Y. X., Wong, H. T., Wu, S. Y., Wu, Y. C., Xing, H. Y., Xu, R., Xu, Y., Xue, T., Yan, Y. L., Yi, N., Yu, C. X., Yu, H. J., Yue, J. F., Zeng, M., Zeng, Z., Zhang, F. S., Zhang, L., Zhang, Z. H., Zhang, Z. Y., Zhao, K. K., Zhao, M. G., Zhou, J. F., Zhou, Z. Y., and Zhu, J. J.

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

We operated a p-type point contact high purity germanium (PPCGe) detector (CDEX-1B, 1.008 kg) in the China Jinping Underground Laboratory (CJPL) for 500.3 days to search for neutrinoless double beta ($0\nu\beta\beta$) decay of $^{76}$Ge. A total of 504.3 kg$\cdot$day effective exposure data was accumulated. The anti-coincidence and the multi/single-site event (MSE/SSE) discrimination methods were used to suppress the background in the energy region of interest (ROI, 1989$-$2089 keV for this work) with a factor of 23. A background level of 0.33 counts/(keV$\cdot$kg$\cdot$yr) was realized. The lower limit on the half life of $^{76}$Ge $0\nu\beta\beta$ decay was constrained as $T_{1/2}^{0\nu}\ > \ {1.0}\times 10^{23}\ \rm yr\ (90\% \ C.L.)$, corresponding to the upper limits on the effective Majorana neutrino mass: $\langle m_{\beta\beta}\rangle < $3.2$-$7.5$\ \mathrm{eV}$., Comment: 11 pages, 12 figures, 2 tables. Version updated to match CPC version

Published
2023
Full Text
View/download PDF

29. Preliminary results on the 233U capture cross section and alpha ratio measured at n_TOF (CERN) with the fission tagging technique

Author

Bacak M., Aiche M., Bélier G., Berthoumieux E., Diakaki M., Dupont E., Gunsing F., Heyse J., Kopecky S., Laurent B., Leeb H., Mathieu L., Schillebeeckx P., Serot O., Taieb J., Vlachoudis V., Aberle O., Andrzejewski J., Audouin L., Balibrea J., Barbagallo M., Bečvář F., Billowes J., Bosnar D., Brown A., Caamaño M., Calviño F., Calviani M., Cano-Ott D., Cardella R., Casanovas A., Cerutti F., Chen Y. H., Chiaveri E., Colonna N., Cortés G., Cortés-Giraldo M. A., Cosentino L., Damone L. A., Domingo-Pardo C., Dressler R., Durán I., Fernández-Domínguez B., Ferrari A., Ferreira P., Finocchiaro P., Furman V., Göbel K., García A. R., Gawlik A., Gilardoni S., Glodariu T., Gonçalves I. F., González-Romero E., Griesmayer E., Guerrero C., Harada H., Heinitz S., Jenkins D. G., Jericha E., Käppeler F., Kadi Y., Kalamara A., Kavrigin P., Kimura A., Kivel N., Knapova I., Kokkoris M., Krtička M., Kurtulgil D., Leal-Cidoncha E., Lederer C., Lerendegui-Marco J., Meo S. Lo, Lonsdale S. J., Macina D., Manna A., Marganiec J., Martínez T., Masi A., Massimi C., Mastinu P., Mastromarco M., Maugeri E. A., Mazzone A., Mendoza E., Mengoni A., Milazzo P. M., Mingrone F., Musumarra A., Negret A., Nolte R., Oprea A., Patronis N., Pavlik A., Perkowski J., Porras I., Praena J., Quesada J. M., Radeck D., Rauscher T., Reifarth R., Rubbia C., Ryan J. A., Sabaté-Gilarte M., Saxena A., Schumann D., Sedyshev P., Smith A. G., Sosnin N. V., Stamatopoulos A., Tagliente G., Tain J. L., Tarifeño-Saldivia A., Tassan-Got L., Valenta S., Vannini G., Variale V., Vaz P., Ventura A., Vlastou R., Wallner A., Warren S., Weiss C., Woods P. J., Wright T., and Žugec P.

Subjects
Physics, QC1-999
Abstract

233U is of key importance among the fissile nuclei in the Th-U fuel cycle. A particularity of 233U is its small neutron capture cross-section, which is on average about one order of magnitude lower than the fission cross-section. The accuracy in the measurement of the 233U capture cross-section depends crucially on an efficient capture-fission discrimination, thus a combined set-up of fission and γ-detectors is needed. A measurement of the 233U capture cross-section and capture-to-fission ratio was performed at the CERN n_TOF facility. The Total Absorption Calorimeter (TAC) of n_TOF was employed as γ-detector coupled with a novel compact ionization chamber as fission detector. A brief description of the experimental set-up will be given, and essential parts of the analysis procedure as well as the preliminary response of the set-up to capture are presented and discussed.

Published
2019
Full Text
View/download PDF

30. Measurement of the 244Cm and 246Cm neutron-induced capture cross sections at the n_TOF facility

Author

Alcayne V., Kimura A., Mendoza E., Cano-Ott D., Martínez T., Aberle O., Andrzejewski J., Audouin L., Bécares V., Bacak M., Barbagallo M., Becčvář 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-Domínguez B., Ferrari A., Finocchiaro P., Furman V., Göbel K., Gawlik A., Gilardoni S., Glodariu T., Gonçalves I. F., González-Romero E., Guerrero C., Gunsing F., Harada H., Heinitz S., Heyse J., Jenkins D. G., Käppeler F., Kadi Y., Katabuchi T., Kivel N., Knapova I., 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., 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., Perkowski J., Persanti L., Porras I., Praena J., Quesada J. M., Radeck D., Ramos-Doval D., Rauscher T., Reifarth R., Rochman D., Sabaté-Gilarte M., Saxena A., Schillebeeckx P., Schumann D., Simone S., 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., Vescovi D., Vlachoudis V., Vlastou R., Wallner A., Woods P. J., Wright T., and Žugec P.

Subjects
Physics, QC1-999
Abstract

The neutron capture reactions of the 244Cm and 246Cm isotopes open the path for the formation of heavier Cm isotopes and 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. There are only two previous 244Cm and 246Cm capture cross section measurements: one in 1969 using a nuclear explosion [1] and the most recent data measured at J-PARC in 2010 [2]. The data for both isotopes are very scarce due to the difficulties in performing the measurements: high intrinsic activity of the samples and limited facilities capable of providing isotopically enriched samples. We have measured both neutron capture cross sections at the n_TOF Experimental Area 2 (EAR-2) with three C6 D6 detectors and also at Area 1 (EAR-1) with the TAC. Preliminary results assessing the quality and limitations (back-ground subtraction, measurement technique and counting statistics) of this new experimental datasets are presented and discussed.

Published
2019
Full Text
View/download PDF

31. 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
Full Text
View/download PDF

32. Measurement of the radiative capture cross section of the s-process branching points 204Tl and 171Tm at the n_TOF facility (CERN)

Author

Casanovas A., Domingo-Pardo C., Guerrero C., Lerendegui-Marco J., Calviño F., Tarifeño-Saldivia A., Dressler R., Heinitz S., Kivel N., Quesada J. M., Schumann D., Aberle O., Alcayne V., Andrzejewski J., Audouin L., Bécares V., Bacak M., Barbagallo M., Bečvář F., Bellia G., Berthoumieux E., Billowes J., Bosnar D., Brown A., Busso M., Caamaño M., Caballero-Ontanaya L., Calviani M., Cano-Ott D., 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., Dupont E., Durán I., Eleme Z., Fernández-Domínguez B., Ferrari A., Ferreira P., Finocchiaro P., Furman V., Göbel K., Gawlik A., Gilardoni S., Glodariu T., Gonçalves I. F., González-Romero E., Gunsing F., Heyse J., Jenkins D. G., Käppeler F., Kadi Y., Katabuchi T., Kimura A., Kokkoris M., Kopatch Y., Krtička M., Kurtulgil D., Ladarescu I., Lederer-Woods C., Meo S. Lo, Lonsdale S. J., Macina D., 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., Persanti L., Porras I., Praena J., Radeck D., Ramos D., Rauscher T., Reifarth R., Rochman D., Sabaté-Gilarte M., Saxena A., Schillebeeckx P., Simone S., Smith A. G., Sosnin N. V., Stamatopoulos A., Tagliente G., Tain J. L., Talip T., Tassan-Got L., Tsinganis A., Ulrich J., Valenta S., Vannini G., Variale V., Vaz P., Ventura A., Vlachoudis V., Vlastou R., Wallner A., Woods P. J., Wright T., Žugec P., and Köster U

Subjects
Physics, QC1-999
Abstract

The neutron capture cross section of some unstable nuclei is especially relevant for s-process nucleosynthesis studies. This magnitude is crucial to determine the local abundance pattern, which can yield valuable information of the s-process stellar environment. In this work we describe the neutron capture (n,γ) measurement on two of these nuclei of interest, 204Tl and 171Tm, from target production to the final measurement, performed successfully at the n_TOF facility at CERN in 2014 and 2015. Preliminary results on the ongoing experimental data analysis will also be shown. These results include the first ever experimental observation of capture resonances for these two nuclei.

Published
2018
Full Text
View/download PDF

33. First Measurement of 72Ge(n, γ) at n_TOF

Author

Dietz M., Lederer-Woods C., Aberle O., Andrzejewski J., Audouin L., Bacak M., Balibrea J., Barbagallo M., Bečvář F., Berthoumieux E., Billowes J., Bosnar D., Brown A., Caamaño M., Calviño F., Calviani M., Cano-Ott D., Cardella R., Casanovas A., Cerutti F., Chen Y. H., Chiaveri E., Colonna N., Cortés G., Cortés-Giraldo M. A, Cosentino L., Damone L. A., Diakaki M., Domingo-Pardo C., Dressler R., Dupont E., Durán I., Fernández-Dominguez B., Ferrari A., Ferreira P., Finocchiaro P., Furman V., Göbel K., García A. R., Garg R., Gawlik A., Gilardoni S., Glodariu T., Goncalves 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., Kahl D., Kalamara A., Kavrigin P., Kimura A., Kivel N., Kokkoris M., Krtička M., Kurtulgil D., Leal-Cidoncha E., Leeb H., Lerendegui-Marco J., Lo Meo S., Lonsdale S. J, Macina D., Marganiec J., Martínez T., Masi A., Massimi C., Mastinu P., Mastromarco M., Maugeri E. A, Mazzone A., Mendoza E., Mengoni A., Milazzo P. M, Mingrone F., Musumarra A., Negret A., Nolte R., Oprea A., Patronis N., Pavlik A., Perkowski J., Porras I., Praena J., Quesada J. M, Radeck D., Rauscher T., Reifarth R., Rubbia C., Ryan J. A, Sabateé-Gilarte M., Saxena A., Schillebeeckx P., Schumann D., Sedyshev P., Smith A. G, Sosnin N. V, Stamatopoulos A., Tagliente G., Tain J. L, Tarifeño-Saldivia A., Tassan-Got L., Valenta S., Vannini G., Variale V., Vaz P., Ventura A., Vlachoudis V., Vlastou R., Wallner A., Warren S., Weiss C., Woods P. J, Wright T., and Žugec P.

Subjects
Physics, QC1-999
Abstract

The slow neutron capture process (s-process) is responsible for producing about half of the elemental abundances heavier than iron in the universe. Neutron capture cross sections on stable isotopes are a key nuclear physics input for s-process studies. The 72Ge(n, γ) cross section has an important influence on production of isotopes between Ge and Zr during s-process in massive stars and therefore experimental data are urgently required. 72Ge(n, γ) was measured at the neutron time-of-flight facility n_TOF (CERN) for the first time at stellar energies. The measurement was performed using an enriched 72GeO2 sample at a flight path of 185m with a set of liquid scintillation detectors (C6D6). The motivation, experiment and current status of the data analysis are reported.

Published
2018
Full Text
View/download PDF

34. Search for boosted keV-MeV light dark matter particles from evaporating primordial black holes at the CDEX-10 experiment

Author

Zhang, Z. H., Yang, L. T., Yue, Q., Kang, K. J., Li, Y. J., An, H. P., C., Greeshma, Chang, J. P., Chen, Y. H., Cheng, J. P., Dai, W. H., Deng, Z., Fang, C. H., Geng, X. P., Gong, H., Guo, Q. J., Guo, X. Y., He, L., He, S. M., Hu, J. W., Huang, H. X., Huang, T. C., Jia, H. T., Jiang, X., Karmakar, S., Li, H. B., Li, J. M., Li, J., Li, Q. Y., Li, R. M. J., Li, X. Q., Li, Y. L., Liang, Y. F., Liao, B., Lin, F. K., Lin, S. T., Liu, J. X., Liu, S. K., Liu, Y. D., Liu, Y., Liu, Y. Y., Liu, Z. Z., Ma, H., Mao, Y. C., Nie, Q. Y., Ning, J. H., Pan, H., Qi, N. C., Ren, J., Ruan, X. C., She, Z., Singh, M. K., Sun, T. X., Tang, C. J., Tang, W. Y., Tian, Y., Wang, G. F., Wang, L., Wang, Q., Wang, Y. F., Wang, Y. X., Wong, H. T., Wu, S. Y., Wu, Y. C., Xing, H. Y., Xu, R., Xu, Y., Xue, T., Yan, Y. L., Yi, N., Yu, C. X., Yu, H. J., Yue, J. F., Zeng, M., Zeng, Z., Zhang, B. T., Zhang, F. S., Zhang, L., Zhang, Z. Y., Zhao, K. K., Zhao, M. G., Zhou, J. F., Zhou, Z. Y., and Zhu, J. J.

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

We present novel constraints on boosted light dark matter particles (denoted as ``$\chi$'') from evaporating primordial black holes (PBHs) using 205.4 kg$\cdot$day data from the China Jinping Underground Laboratory's CDEX-10 p-type point contact germanium detector with a 160 eVee analysis threshold. $\chi$ from PBHs with masses ranging from 1$\times$10$^{15}$ g to 7$\times$10$^{16}$ g are searched in this work. In the presence of PBH abundance compatible with present bounds, our result excludes the $\chi$-nucleon elastic-scattering cross section region from 3.4$\times$10$^{-32}$ cm$^{2}$ to 2.3$\times$10$^{-29}$ cm$^{2}$ for $\chi$ of 1 keV to 24 MeV from PBHs with masses of 5$\times$10$^{15}$ g, as well as from 1.1$\times$10$^{-28}$ cm$^{2}$ to 7.6$\times$10$^{-28}$ cm$^{2}$ for $\chi$ of 1 keV to 0.6 MeV from PBHs with masses of 7$\times$10$^{16}$ g. If the $\chi$-nucleon elastic-scattering cross section can be determined in the future, the abundance of PBHs may be severely constrained by $\chi$ evaporation. With the lower threshold (160 eVee) of the CDEX-10 experiment compared to the previously used experiments, this work allows for a better reach at soft spectra produced by heavier PBHs, which demonstrates the vast potential of such a technical route to pursue $\chi$ from larger PBHs with a low threshold., Comment: 8 pages, 6 figures. Version updated to match PRD version

Published
2022
Full Text
View/download PDF

35. Deep underground laboratory measurement of $^{13}$C($\alpha$,$n$)$^{16}$O in the Gamow windows of the $s$- and $i$-processes

Author

Gao, B., Jiao, T. Y., Li, Y. T., Chen, H., Lin, W. P., An, Z., Ru, L. H., Zhang, Z. C., Tang, X. D., Wang, X. Y., Zhang, N. T., Fang, X., Xie, D. H., Fan, Y. H., Ma, L., Zhang, X., Bai, F., Wang, P., Fan, Y. X., Liu, G., Huang, H. X., Wu, Q., Zhu, Y. B., Chai, J. L., Li, J. Q., Sun, L. T., Wang, S., Cai, J. W., Li, Y. Z., Su, J., Zhang, H., Li, Z. H., Li, Y. J., Li, E. T., Chen, C., Shen, Y. P., Lian, G., Guo, B., Li, X. Y., Zhang, L. Y., He, J. J., Sheng, Y. D., Chen, Y. J., Wang, L. H., Zhang, L., Cao, F. Q., Nan, W., Nan, W. K., Li, G. X., Song, N., Cui, B. Q., Chen, L. H., Ma, R. G., Yan, S. Q., Liao, J. H., Wang, Y. B., Zeng, S., Nan, D., Fan, Q. W., Qi, N. C., Sun, W. L., Guo, X. Y., Zhang, P., Chen, Y. H., Zhou, Y., Zhou, J. F., He, J. R., Shang, C. S., Li, M. C., Kubono, S., Liu, W. P., deBoer, R. J., Wiescher, M., and Pignatari, M.

Subjects
Nuclear Experiment
Abstract

The $^{13}$C($\alpha$,$n$)$^{16}$O reaction is the main neutron source for the slow-neutron-capture (s-) process in Asymptotic Giant Branch stars and for the intermediate (i-) process. Direct measurements at astrophysical energies in above-ground laboratories are hindered by the extremely small cross sections and vast cosmic-ray induced background. We performed the first consistent direct measurement in the range of $E_{\rm c.m.}=$0.24 MeV to 1.9 MeV using the accelerators at the China Jinping Underground Laboratory (CJPL) and Sichuan University. Our measurement covers almost the entire i-process Gamow window in which the large uncertainty of the previous experiments has been reduced from 60\% down to 15\%, eliminates the large systematic uncertainty in the extrapolation arising from the inconsistency of existing data sets, and provides a more reliable reaction rate for the studies of the s- and i-processes along with the first direct determination of the alpha strength for the near-threshold state.

Published
2022
Full Text
View/download PDF

36. Investigation of wetting layers in InAs/GaAs self-assembled nanostructures with reflectance difference spectroscopy

Author

Zhang, H. Y., Chen, Y. H., and Wang, Z. G.

Subjects
Condensed Matter - Materials Science
Abstract

As a system with both profound physics and promising application potentials, the strain-induced self-assembled semiconductor nanostructures have been investigated for decades of years. The optical and electrical properties of this system are mainly determined by the nanostructures, but can be greatly affected by the generally existent two dimensional structures from which the nanostructures evolve, the so called wetting layer (WL). The WL configurations can be varied with different growth conditions, and further influence the nanostructure morphology and properties. This is a reviewing article introducing some recent progresses in investigating the evolution of WLs in InAs/GaAs system with reflectance difference spectroscopy. Different kinds of WL evolution processes in Stranski-Krastanov growth mode are introduced. The segregation and desorption of indium atoms and the effect of growth interruption are mentioned. The existence and the evolution process of wetting layers in droplet epitaxy method are also discussed.

Published
2022
Full Text
View/download PDF

37. Search for exotic interactions of solar neutrinos in the CDEX-10 experiment

Author

Geng, X. P., Yang, L. T., Yue, Q., Kang, K. J., Li, Y. J., An, H. P., C., Greeshma, Chang, J. P., Chen, Y. H., Cheng, J. P., Dai, W. H., Deng, Z., Fang, C. H., Gong, H., Guo, Q. J., Guo, X. Y., He, L., He, S. M., Hu, J. W., Huang, H. X., Huang, T. C., Jia, H. T., Jiang, X., Karmakar, S., Li, H. B., Li, J. M., Li, J., Li, Q. Y., Li, R. M. J., Li, X. Q., Li, Y. L., Liang, Y. F., Liao, B., Lin, F. K., Lin, S. T., Liu, J. X., Liu, S. K., Liu, Y. D., Liu, Y., Liu, Y. Y., Liu, Z. Z., Ma, H., Mao, Y. C., Nie, Q. Y., Ning, J. H., Pan, H., Qi, N. C., Ren, J., Ruan, X. C., She, Z., Singh, M. K., Sun, T. X., Tang, C. J., Tang, W. Y., Tian, Y., Wang, G. F., Wang, L., Wang, Q., Wang, Y. F., Wang, Y. X., Wong, H. T., Wu, S. Y., Wu, Y. C., Xing, H. Y., Xu, R., Xu, Y., Xue, T., Yan, Y. L., Yi, N., Yu, C. X., Yu, H. J., Yue, J. F., Zeng, M., Zeng, Z., Zhang, B. T., Zhang, F. S., Zhang, L., Zhang, Z. H., Zhang, Z. Y., Zhao, K. K., Zhao, M. G., Zhou, J. F., Zhou, Z. Y., and Zhu, J. J.

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

We investigate exotic neutrino interactions using the 205.4 kg$\cdot$day dataset from the CDEX-10 experiment at the China Jinping Underground Laboratory. New constraints on the mass and couplings of new gauge bosons are presented. Two nonstandard neutrino interactions are considered: a $U(1)_{B-L}$ gauge-boson-induced interaction between an active neutrino and electron/nucleus, and a dark-photon-induced interaction between a sterile neutrino and electron/nucleus via kinetic mixing with a photon. This work probes an unexplored parameter space involving sterile neutrino coupling with a dark photon. New laboratory limits are derived on dark photon masses below $1~{\rm eV}/c^{2}$ at some benchmark values of $\Delta m_{41}^{2}$ and $g^{\prime2}{\rm{sin}}^{2}2\theta_{14}$., Comment: 6 pages, 4 figures. Version updated to match PRD version

Published
2022
Full Text
View/download PDF

38. Exotic Dark Matter Search with CDEX-10 Experiment at China's Jinping Underground Laboratory

Author

Dai, W. H., Jia, L. P., Ma, H., Yue, Q., Kang, K. J., Li, Y. J., An, H. P., C., Greeshma, Chang, J. P., Chen, Y. H., Cheng, J. P., Deng, Z., Fang, C. H., Geng, X. P., Gong, H., Guo, Q. J., Guo, X. Y., He, L., He, S. M., Hu, J. W., Huang, H. X., Huang, T. C., Jia, H. T., Jiang, X., Karmakar, S., Li, H. B., Li, J. M., Li, J., Li, Q. Y., Li, R. M. J., Li, X. Q., Li, Y. L., Liang, Y. F., Liao, B., Lin, F. K., Lin, S. T., Liu, S. K., Liu, Y. D., Liu, Y., Liu, Y. Y., Liu, Z. Z., Mao, Y. C., Nie, Q. Y., Ning, J. H., Pan, H., Qi, N. C., Ren, J., Ruan, X. C., She, Z., Singh, M. K., Sun, T. X., Tang, C. J., Tang, W. Y., Tian, Y., Wang, G. F., Wang, L., Wang, Q., Wang, Y., Wang, Y. X., Wong, H. T., Wu, S. Y., Wu, Y. C., Xing, H. Y., Xu, R., Xu, Y., Xue, T., Yan, Y. L., Yang, L. T., Yi, N., Yu, C. X., Yu, H. J., Yue, J. F., Zeng, M., Zeng, Z., Zhang, B. T., Zhang, F. S., Zhang, L., Zhang, Z. H., Zhang, Z. Y., Zhao, K. K., Zhao, M. G., Zhou, J. F., Zhou, Z. Y., and Zhu, J. J.

Subjects
High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract

A search for exotic dark matter (DM) in the sub-GeV mass range has been conducted using 205 kg$\cdot$day data taken from a p-type point contact germanium detector of CDEX-10 experiment at China Jinping underground laboratory. New low-mass dark matter searching channels, neutral current fermionic DM absorption ($\chi+A\rightarrow \nu+A$) and DM-nucleus 3$\rightarrow$2 scattering ($\chi+\chi+A\rightarrow \phi+A$), have been analyzed with an energy threshold of 160 eVee. No significant signal was found. Thus new limits on the DM-nucleon interaction cross section are set for both models at sub-GeV DM mass region. A cross section limit for the fermionic DM absorption is set to be $\rm 2.5\times 10^{-46} cm^2$(90\% C.L.) at DM mass of 10 MeV/c$^2$. For the DM-nucleus 3$\rightarrow$2 scattering scenario, limits are extended to DM mass of 5 MeV/c$^2$ and 14 MeV/c$^2$ for the massless dark photon and bound DM final state, respectively., Comment: 5 pages, 7 figures

Published
2022
Full Text
View/download PDF

40. Constraints on Sub-GeV Dark Matter--Electron Scattering from the CDEX-10 Experiment

Author

Zhang, Z. Y., Yang, L. T., Yue, Q., Kang, K. J., Li, Y. J., Agartioglu, M., An, H. P., Chang, J. P., Chen, Y. H., Cheng, J. P., Dai, W. H., Deng, Z., Fang, C. H., Geng, X. P., Gong, H., Guo, Q. J., Guo, X. Y., He, L., He, S. M., Hu, J. W., Huang, H. X., Huang, T. C., Jia, H. T., Jiang, X., Li, H. B., Li, J. M., Li, J., Li, Q. Y., Li, R. M. J., Li, X. Q., Li, Y. L., Liang, Y. F., Liao, B., Lin, F. K., Lin, S. T., Liu, S. K., Liu, Y. D., Liu, Y., Liu, Y. Y., Liu, Z. Z., Ma, H., Mao, Y. C., Nie, Q. Y., Ning, J. H., Pan, H., Qi, N. C., Ren, J., Ruan, X. C., Saraswat, K., Sharma, V., She, Z., Singh, M. K., Sun, T. X., Tang, C. J., Tang, W. Y., Tian, Y., Wang, G. F., Wang, L., Wang, Q., Wang, Y., Wang, Y. X., Wong, H. T., Wu, S. Y., Wu, Y. C., Xing, H. Y., Xu, R., Xu, Y., Xue, T., Yan, Y. L., Yeh, C. H., Yi, N., Yu, C. X., Yu, H. J., Yue, J. F., Zeng, M., Zeng, Z., Zhang, B. T., Zhang, F. S., Zhang, L., Zhang, Z. H., Zhao, K. K., Zhao, M. G., Zhou, J. F., Zhou, Z. Y., and Zhu, J. J.

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

We present improved germanium-based constraints on sub-GeV dark matter via dark matter--electron ($\chi$-$e$) scattering using the 205.4 kg$\cdot$day dataset from the CDEX-10 experiment. Using a novel calculation technique, we attain predicted $\chi$-$e$ scattering spectra observable in high-purity germanium detectors. In the heavy mediator scenario, our results achieve 3 orders of magnitude of improvement for $m_{\chi}$ larger than 80 MeV/c$^2$ compared to previous germanium-based $\chi$-$e$ results. We also present the most stringent $\chi$-$e$ cross-section limit to date among experiments using solid-state detectors for $m_{\chi}$ larger than 90 MeV/c$^2$ with heavy mediators and $m_{\chi}$ larger than 100 MeV/c$^2$ with electric dipole coupling. The result proves the feasibility and demonstrates the vast potential of a new $\chi$-$e$ detection method with high-purity germanium detectors in ultralow radioactive background., Comment: 6 pages, 3 figures. Version updated to match PRL version

Published
2022
Full Text
View/download PDF

41. Measurement of the prompt fission γ235-rays from slow neutron-induced fission of γ235U with STEFF

Author

Wright, T., Smith, A. G., Sosnin, N. V., Bennett, S. A., Davies, P. J., Popescu, A. V., Ryan, J. A., Sekhar, A., Warren, S., Aberle, O., Amaducci, S., Andrzejewski, J., Audouin, L., Bacak, M., Balibrea, J., Barbagallo, M., Bečvář, F., Berthoumieux, E., Billowes, J., Bosnar, D., Brown, A., Caamaño, M., Calviño, F., Calviani, M., Cano-Ott, D., Cardella, R., Casanovas, A., Cerutti, F., Chen, Y. H., Chiaveri, E., Colonna, N., Cortés, G., Cortés-Giraldo, M. A., Cosentino, L., Damone, L. A., Diakaki, M., Domingo-Pardo, C., Dressler, R., Dupont, E., Durán, I., Fernández-Domínguez, B., Ferrari, A., Ferreira, P., Finocchiaro, P., Furman, V., Göbel, K., García, A. R., Gawlik-Ramięga, 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., Kokkoris, M., Krtička, M., Kurtulgil, D., Leal-Cidoncha, E., Lederer-Woods, C., Leeb, H., Lerendegui-Marco, J., Meo, S. Lo, Lonsdale, S. J., Macina, D., Manna, A., Marganiec, J., Martínez, T., Masi, A., Massimi, C., Mastinu, P., Mastromarco, M., Maugeri, E. A., Mazzone, A., Mendoza, E., Mengoni, A., Milazzo, P. M., Mingrone, F., Musumarra, A., Negret, A., Nolte, R., Oprea, A., Patronis, N., Pavlik, A., Perkowski, J., Porras, I., Praena, J., Quesada, J. M., Radeck, D., Rauscher, T., Reifarth, R., Rubbia, C., Sabaté-Gilarte, M., Saxena, A., Schillebeeckx, P., Schumann, D., Sedyshev, P., 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., Weiss, C., Woods, P. J., and Žugec, P.

Published
2024
Full Text
View/download PDF

42. The Nuclear Astrophysics program at n_TOF (CERN)

Author

Colonna N., 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., Clai G., Cortés G., Cortés-Giraldo M. A., Cosentino, Cristallo S., Damone L. A., Diakaki M., Domingo-Pardo C., Dressler L. R., Dupont E., Durán I., Fernández-Domínguez B., Ferrari A., Ferreira P., Finocchiaro P., Furman V., Göbel K., García A. R., Gawlik A., Gilardoni S., Glodariu T., Gonçalves I. F., González E., Griesmayer E., Guerrero C., Gunsing F., Harada H., Heinitz S., Hernandez-Prieto A., Heyse J., Jenkins D. G., Jericha E., Käppeler F., Kadi Y., Kalamara A., Kavrigin P., Kimura A., Kivel N., Kokkoris M., Kroll J., Krtička M., Kurtulgil D., Langer C., Leal-Cidoncha E., Lederer C., Lerendegui-Marco J., Leeb H., Lo Meo S., Lonsdale S. J., Losito S., Macina D., Mallik A., Marganiec J., Martínez T., Masi A., Massimi C., Mastinu P., Mastromarco M., Maugeri E. A., Mazzone A., Mendoza E., Mengoni A., Mingrone F., Milazzo P. M., Mirea M., Musumarra A., Negret A., Nolte R., Oprea A., Patronis N., Pavlik A., Perkowski J., Piersanti L., Porras I., Praena J., Quesada J. M., Radeck D., Rauscher T., Reifarth R., Riego A., Robles M.S., 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., Tsinganis A., Valenta S., Vannini G., Variale V., Vaz P., Ventura A., Vlachoudis V., Vlastou R., Wallner A., Warren S., Weiss C., Woods P. J., Wright T., and Žugec P.

Subjects
Physics, QC1-999
Abstract

An important experimental program on Nuclear Astrophysics is being carried out at the n_TOF since several years, in order to address the still open issues in stellar and primordial nucleosynthesis. Several neutron capture reactions relevant to s-process nucleosynthesis have been measured so far, some of which on important branching point radioisotopes. Furthermore, the construction of a second experimental area has recently opened the way to challenging measurements of (n, charged particle) reactions on isotopes of short half-life. The Nuclear Astrophysics program of the n_TOF Collaboration is here described, with emphasis on recent results relevant for stellar nucleosynthesis, stellar neutron sources and primordial nucleosynthesis.

Published
2017
Full Text
View/download PDF

43. Search for Neutrinoless Double-Beta Decay of $^{76}$Ge with a Natural Broad Energy Germanium Detector

Author

CDEX collaboration, Dai, W. H., Ma, H., Yue, Q., She, Z., Kang, K. J., Li, Y. J., Agartioglu, M., An, H. P., Chang, J. P., Chen, Y. H., Cheng, J. P., Deng, Z., Fang, C. H., Geng, X. P., Gong, H., Guo, Q. J., Guo, X. Y., He, L., He, S. M., Hu, J. W., Huang, H. X., Huang, T. C., Jia, H. T., Jiang, X., Li, H. B., Li, J. M., Li, J., Li, Q. Y., Li, R. M. J., Li, X. Q., Li, Y. L., Liang, Y. F., Liao, B., Lin, F. K., Lin, S. T., Liu, S. K., Liu, Y. D., Liu, Y., Liu, Y. Y., Liu, Z. Z., Mao, Y. C., Nie, Q. Y., Ning, J. H., Pan, H., Qi, N. C., Ren, J., Ruan, X. C., Saraswat, K., Sharma, V., Singh, M. K., Sun, T. X., Tang, C. J., Tang, W. Y., Tian, Y., Wang, G. F., Wang, L., Wang, Q., Wang, Y., Wang, Y. X., Wong, H. T., Wu, S. Y., Wu, Y. C., Xing, H. Y., Xu, R., Xu, Y., Xue, T., Yan, Y. L., Yang, L. T., Yeh, C. H., Yi, N., Yu, C. X., Yu, H. J., Yue, J. F., Zeng, M., Zeng, Z., Zhang, B. T., Zhang, F. S., Zhang, L., Zhang, Z. H., Zhang, Z. Y., Zhao, K. K., Zhao, M. G., Zhou, J. F., Zhou, Z. Y., and Zhu, J. J.

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

A natural broad energy germanium (BEGe) detector is operated in the China Jinping Underground Laboratory (CJPL) for a feasibility study of building the next generation experiment of the neutrinoless double-beta (0{$\nu\beta\beta$}) decay of $^{76}$Ge. The setup of the prototype facility, characteristics of the BEGe detector, background reduction methods, and data analysis are described in this paper. A background index of 6.4$\times$10$^{-3}$ counts/(keV$\cdot$kg$\cdot$day) is achieved and 1.86 times lower than our previous result of the CDEX-1 detector. No signal is observed with an exposure of 186.4 kg$\cdot$day, thus a limit on the half life of $^{76}$Ge 0$\nu\beta\beta$ decay is set at T$_{1/2}^{0\nu}$ $>$ 5.62$\times$10$^{22}$ yr at 90% C.L.. The limit corresponds to an effective Majorana neutrino mass in the range of 4.6 $\sim$ 10.3 eV, dependent on the nuclear matrix elements., Comment: 10 pages, 15 figures

Published
2022
Full Text
View/download PDF

44. 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

45. Constraints on sub-GeV dark matter boosted by cosmic rays from the CDEX-10 experiment at the China Jinping Underground Laboratory

Author

Xu, R., Yang, L. T., Yue, Q., Kang, K. J., Li, Y. J., Agartioglu, M., An, H. P., Chang, J. P., Chen, Y. H., Cheng, J. P., Dai, W. H., Deng, Z., Fang, C. H., Geng, X. P., Gong, H., Guo, X. Y., Guo, Q. J., He, L., He, S. M., Hu, J. W., Huang, H. X., Huang, T. C., Jia, H. T., Jiang, X., Li, H. B., Li, J. M., Li, J., Li, Q. Y., Li, R. M. J., Li, X. Q., Li, Y. L., Liang, Y. F., Liao, B., Lin, F. K., Lin, S. T., Liu, S. K., Liu, Y., Liu, Y. D., Liu, Y. Y., Liu, Z. Z., Ma, H., Mao, Y. C., Nie, Q. Y., Ning, J. H., Pan, H., Qi, N. C., Ren, J., Ruan, X. C., Saraswat, K., Sharma, V., She, Z., Singh, M. K., Sun, T. X., Tang, C. J., Tang, W. Y., Tian, Y., Wang, G. F., Wang, L., Wang, Q., Wang, Y., Wang, Y. X., Wong, H. T., Wu, S. Y., Wu, Y. C., Xing, H. Y., Xu, Y., Xue, T., Yan, Y. L., Yeh, C. H., Yi, N., Yu, C. X., Yu, H. J., Yue, J. F., Zeng, M., Zeng, Z., Zhang, B. T., Zhang, F. S., Zhang, L., Zhang, Z. H., Zhang, Z. Y., Zhao, K. K., Zhao, M. G., Zhou, J. F., Zhou, Z. Y., and Zhu, J. J.

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

We present new constraints on light dark matter boosted by cosmic rays (CRDM) using the 205.4 kg day data of the CDEX-10 experiment conducted at the China Jinping Underground Laboratory. The Monte Carlo simulation package CJPL\_ESS was employed to evaluate the Earth shielding effect. Several key factors have been introduced and discussed in our CRDM analysis, including the contributions from heavier CR nuclei than proton and helium, the inhomogeneity of CR distribution, and the impact of the form factor in the Earth attenuation calculation. Our result excludes the dark matter--nucleon elastic scattering cross-section region from $1.7\times 10^{-30}$ to $10^{-26}~\rm cm^2$ for dark matter of 10 keV$/c^2$ to 1 GeV$/c^2$., Comment: 9 pages, 7 figures. Version updated to match PRD version

Published
2022
Full Text
View/download PDF

46. Studies of the Earth shielding effect to direct dark matter searches at the China Jinping Underground Laboratory

Author

Liu, Z. Z., Yang, L. T., Yue, Q., Yeh, C. H., Kang, K. J., Li, Y. J., Agartioglu, M., An, H. P., Chang, J. P., Chen, J. H., Chen, Y. H., Cheng, J. P., Dai, W. H., Deng, Z., Fang, C. H., Geng, X. P., Gong, H., Guo, X. Y., Guo, Q. J., He, L., He, S. M., Hu, J. W., Huang, H. X., Huang, T. C., Jia, H. T., Jiang, X., Li, H. B., Li, J. M., Li, J., Li, R. M. J., Li, X. Q., Li, Y. L., Liao, B., Lin, F. K., Lin, S. T., Liu, S. K., Liu, Y., Liu, Y. D., Liu, Y. Y., Ma, H., Mao, Y. C., Nie, Q. Y., Ning, J. H., Pan, H., Qi, N. C., Ren, J., Ruan, X. C., Saraswat, K., Sharma, V., She, Z., Singh, M. K., Sun, T. X., Tang, C. J., Tang, W. Y., Tian, Y., Wang, G. F., Wang, L., Wang, Q., Wang, Y., Wang, Y. X., Wang, Z., Wong, H. T., Wu, S. Y., Wu, Y. C., Xing, H. Y., Xu, Y., Xue, T., Yan, Y. L., Yi, N., Yu, C. X., Yu, H. J., Yue, J. F., Zeng, M., Zeng, Z., Zhang, B. T., Zhang, F. S., Zhang, Z. H., Zhang, Z. Y., Zhao, K. K., Zhao, M. G., Zhou, J. F., Zhou, Z. Y., and Zhu, J. J.

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

Dark matter direct detection experiments mostly operate at deep underground laboratories. It is necessary to consider shielding effect of the Earth, especially for dark matter particles interacting with a large cross section. We analyzed and simulated the Earth shielding effect for dark matter at the China Jinping Underground Laboratory (CJPL) with a simulation package, CJPL Earth Shielding Simulation code (CJPL\_ESS), which is applicable to other underground locations. The further constraints on the $\chi$-N cross section exclusion regions are derived based on the studies with CDEX experiment data., Comment: 8 pages, 8 figures, 2 tables. Version updated to match PRD version

Published
2021
Full Text
View/download PDF

47. High-resolution cross section measurements for neutron interactions on 89Y with incident neutron energies up to 95 keV

Author

Tagliente, G., Milazzo, P. M., Paradela, C., Kopecky, S., Vescovi, D., Alaerts, G., Damone, L. A., Heyse, J., Krtička, M., Schillebeeckx, P., Mengoni, A., Wynants, R., Valenta, S., Aberle, O., Alcayne, V., 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., 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., 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., Jenkins, D. G., Jericha, E., Kadi, Y., Käppeler, F., Kimura, A., Kivel, N., Kokkoris, M., Kopatch, Y., Kurtulgil, D., Ladarescu, I., Larsen, A. C., Lederer-Woods, C., Lerendegui-Marco, J., Lo Meo, S., Lonsdale, S. J., Lugaro, M., Macina, D., Manna, A., Martínez, T., Masi, A., Massimi, C., Mastinu, P. F., Mastromarco, M., Matteucci, F., Maugeri, E., Mazzone, A., Mendoza, E., Michalopoulou, V., 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., Schumann, D., Smith, A. G., Spelta, M., Sosnin, N., Stamatopoulos, A., Tain, J. L., Talip, Z., Tarifeño-Saldivia, A. E., Tassan-Got, L., Torres-Sánchez, P., Tsinganis, A., Ulrich, J., Urlass, S., Vannini, G., Variale, V., Vaz, P., Ventura, A., Vlachoudis, V., Vlastou, R., Wallner, A., Woods, P. J., Wright, T. J., and Žugec, P.

Published
2024
Full Text
View/download PDF

48. EPIC 228782059: Asteroseismology of what could be the coolest pulsating helium-atmosphere white dwarf (DBV) known?

Author

Duan, R. M., Zong, W., Fu, J. -N., Chen, Y. H., Hermes, J. J., Vanderbosch, Zachary P., Ma, X. Y., and Charpinet, S.

Subjects
Astrophysics - Solar and Stellar Astrophysics
Abstract

We present analysis of a new pulsating helium-atmosphere (DB) white dwarf, EPIC~228782059, discovered from 55.1~days of {\em K2} photometry. The long duration, high quality light curves reveal 11 independent dipole and quadruple modes, from which we derive a rotational period of $34.1 \pm 0.4$~hr for the star. An optimal model is obtained from a series of grids constructed using the White Dwarf Evolution Code, which returns $M_{*} = 0.685 \pm 0.003 M_{\odot}$, $T_{\rm{eff}}= 21{,}910 \pm 23$\,K and $\log g = 8.14 \pm0.01$\,dex. These values are comparable to those derived from spectroscopy by Koester \& Kepler ($20{,}860 \pm 160$\,K and $7.94 \pm0.03$\,dex). If these values are confirmed or better constrained by other independent works, it would make EPIC~228782059 one of the coolest pulsating DB white dwarf star known, and would be helpful to test different physical treatments of convection, and to further investigate the theoretical instability strip of DB white dwarf stars., Comment: 9 pages, 5 figures, 2 tables, accepted by ApJ

Published
2021
Full Text
View/download PDF

49. A microscopic theory of Curzon-Ahlborn heat engine

Author

Chen, Y. H., Chen, Jin-Fu, Fei, Zhaoyu, and Quan, H. T.

Subjects
Condensed Matter - Statistical Mechanics
Abstract

Abstract The Curzon-Ahlborn (CA) efficiency, as the efficiency at the maximum power (EMP) of the endoreversible Carnot engine, has a significant impact on finite-time thermodynamics. However, the CA engine model is based on many assumptions. In the past few decades, although a lot of efforts have been made, a microscopic theory of the CA engine is still lacking. By adopting the method of the stochastic differential equation of energy, we formulate a microscopic theory of the CA engine realized with an underdamped Brownian particle in a class of non-harmonic potentials. This theory gives microscopic interpretation of all assumptions made by Curzon and Ahlborn, and thus puts the results about CA engine on a solid foundation. Also, based on this theory, we obtain analytical expressions of the power and the efficiency statistics for the Brownian CA engine. Our research brings new perspectives to experimental studies of finite-time microscopic heat engines featured with fluctuations., Comment: 6+15 pages, 2 figures

Published
2021
Full Text
View/download PDF

50. Surface optical phonon replica in photoluminescence spectroscopy of nitride nanostructures: Crystal structure and surface effects.

Author

Zhang, L., Chen, Y. H., Liu, Q., Liang, Z. W., Pang, C., and Wang, Q.

Subjects
*CRYSTAL structure, *CRYSTAL surfaces, *NANOWIRES, *PHONONS, *SURFACE structure, *NITRIDES, *PHONON scattering
Abstract

The surface optical (SO) phonon replica in photoluminescence (PL) spectroscopy of nitride nanowires (NWs) was theoretically investigated in this study. The dispersive relationships of SO phonon mode in anisotropic wurtzite (WZ) and isotropic zinc-blende (ZB) crystal structure NWs with circular and square cross sections (CSs) were derived within the framework of the dielectric continuum model. Based on the energy and momentum conservation laws, a constraint relationship between the frequency and wave-number was constructed for SO phonon-assisted excitonic PL spectra in the NW structure. By combining the dispersive and constraint relationships, the frequency and wave-number of the SO phonon replica in the PL spectra could be determined. The WZ and ZB crystal structures of nitride semiconductor were considered. The influences of surface factors including the CS shape, dielectric medium, and environment temperature on the frequency and photon wavelength of the band-edge emission of the SO phonon replica were studied in detail. Numerical results reveal that the crystal structure, surface factors, and environment temperature greatly affect the frequency and photon wavelength of the band-edge emission of the SO phonon replica. The calculated results for the photon wavelength agree well with the experimental values of the SO phonon replica in AlN NWs. The results of the dielectric effect obtained here are also supported by previous experimental and theoretical results for nitrides and other semiconductor NWs. The present theoretical scheme and numerical results can be used to analyze and design the SO phonon replica in PL spectra of nanostructures. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results