Search

Your search keyword '"Sprung P"' showing total 1,300 results
Start Over Author "Sprung P"
1,300 results on '"Sprung P"'

1. Resolving the pressure induced 'self-insertion' in skutterudite CoSb3

Author

Wang, Bihan, Pakhomova, Anna, Khandarkhaeva, Saiana, Pillaca, Mirtha, Gille, Peter, Ren, Zhe, Lapkin, Dmitry, Assalauova, Dameli, Alexeev, Pavel, Sergeev, Ilya, Kulkarni, Satishkumar, Weng, Tsu-Chien, Sprung, Michael, Liermann, Hanns-Peter, Vartanyants, Ivan A., and Glazyrin, Konstantin

Subjects
Condensed Matter - Materials Science, Condensed Matter - Disordered Systems and Neural Networks, Condensed Matter - Other Condensed Matter, Condensed Matter - Strongly Correlated Electrons
Abstract

CoSb3, a skutterudite compound, is key in studying thermoelectric materials. Under compression, it undergoes a 'self-insertion' isostructural transition, redistributing large Sb atoms among crystallographic sites. We investigated CoSb3's structural stability up to 70 GPa using single crystal X-ray diffraction and high-resolution X-ray scattering, including Bragg Coherent Diffraction Imaging. We examined the material in three pressure transmitting media (PTMs), exploring how PTMs and nonhydrostatic stresses affect CoSb3. Notably, the 'self-insertion' transition may reduce or even make compressibility negative. Additionally, we report a previously unknown phase transformation from cubic Im-3 to trigonal R-3 above 40 GPa and discuss the phases' distinctive behaviors., Comment: Manuscript: 27 pages, 12 Figures

Published
2024

2. Dynamic X-ray coherent diffraction analysis: bridging the timescales between imaging and photon correlation spectroscopy

Author

Hinsley, Gerard N., Westermeister, Fabian, Wang, Bihan, Ngoi, Kuan Hoon, Singh, Shweta, Rysov, Rustam, Sprung, Michael, Kewish, Cameron M., van Riessen, Grant A., and Vartanyants, Ivan A.

Subjects
Condensed Matter - Mesoscale and Nanoscale Physics, Physics - Applied Physics, Physics - Optics
Abstract

The advent of diffraction limited sources and developments in detector technology opens up new possibilities for the study of materials in situ and operando. Coherent X-ray diffraction techniques such as coherent X-ray diffractive imaging (CXDI) and X-ray photon correlation spectroscopy (XPCS) are capable for this purpose and provide complimentary information, although due to signal-to-noise requirements, their simultaneous demonstration has been limited. Here, we demonstrate a strategy for the simultaneous use of CXDI and XPCS to study in situ the Brownian motion of colloidal gold nanoparticles of 200 nm diameter suspended in a glycerol-water mixture. We visualise the process of agglomeration, examine the spatiotemporal space accessible with the combination of techniques, and demonstrate CXDI with 22 ms temporal resolution., Comment: 29 pages, 12 figures, 40 references

Published
2024

3. High resolution 80Se(n,γ) cross section measurement at CERN n_TOF

Author

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

Subjects
Physics, QC1-999
Abstract

Neutron capture cross section measurements of isotopes close to s-process branching-points are of fundamental importance for the understanding of this nucleosynthesis mechanism through which about 50% of the elements heavier than iron are produced. We present in this contribution the results corresponding to the high resolution measurement, for first time ever, of the 80Se(n, γ) cross section, in which 98 resonances never measured before have been reported. As a consequence, ten times more precise values for the MACS have been obtained compared to previous accepted value adopted in the astrophysical KADoNiS data base.

Published
2023
Full Text
View/download PDF

4. Measurement of the 235U(n,f) cross section relative to the 10B(n,α) reaction with Micromegas detectors at the CERN n_TOF facility: First results

Author

Michalopoulou Veatriki, Diakaki Maria, Vlastou Rosa, Kokkoris Michael, Stamatopoulos Athanasios, Tsinganis Andrea, Eleme Zinovia, Patronis Nikolas, Heyse Jan, Schillebeeckx Peter, Tassan-Got Laurent, Barbagallo Massimo, Colonna Nicola, Urlass Sebastian, Macina Daniela, Chiaveri Enrico, Aberle Oliver, Alcayne Victor, Amaducci Simone, Andrzejewski Józef, Audouin Laurent, Babiano-Suarez Victor, Bacak Michael, Bennett Samuel, Berthoumieux Eric, Billowes Jon, Bosnar Damir, Brown Adam, Busso Maurizio, Caamaño Manuel, Caballero-Ontanaya Luis, Calviño Francisco, Calviani Marco, Cano-Ott Daniel, Casanovas Adria, Cerutti Francesco, Cortés Guillem, Cortés-Giraldo Miguel, Cosentino Luigi, Cristallo Sergio, Damone Lucia-Anna, Davies Paul-John, Dietz Mirco, Domingo-Pardo César, Dressler Rugard, Ducasse Quentin, Dupont Emmeric, Durán Ignacio, Fernández-Domínguez Beatriz, Ferrari Alfredo, Finocchiaro Paolo, Göbel Kathrin, Garg Ruchi, Gawlik-Ramięga Aleksandra, Gilardoni Simone, Gonçalves Isabel, González-Romero Enrique, Guerrero Carlos, Gunsing Frank, Harada Hideo, Heinitz Stephan, Jenkins David, Junghans Arnd, Käppeler† Franz, Kadi Yacine, Kimura Atsushi, Knapová Ingrid, Krtička Milan, Kurtulgil Deniz, Ladarescu Ion, Lederer-Woods Claudia, Leeb Helmut, Lerendegui-Marco Jorge, Lonsdale Sarah-Jane, Manna Alice, Martínez Trinitario, Masi Alessandro, Massimi Cristian, Mastinu Pierfrancesco, Mastromarco Mario, Maugeri Emilio-Andrea, Mazzone Annamaria, Mendoza Emilio, Mengoni Alberto, Milazzo Paolo, Mingrone Federica, Moreno-Soto Javier, Musumarra Agatino, Negret Alexandru, Nolte Ralf, Ogállar Francisco, Oprea Andreea, Pavlik Andreas, Perkowski Jarosław, Piersanti Luciano, Petrone Cristina, Pirovano Elisa, Porras Ignacio, Praena Javier, Quesada José-Manuel, Ramos-Doval Diego, Rauscher Thomas, Reifarth René, Rochman Dimitri, Rubbia Carlo, Sabaté-Gilarte Marta, Saxena Alok, Schumann Dorothea, Sekhar Adhitya, Smith Gavin, Sosnin Nikolay, Sprung Peter, Tagliente Giuseppe, Tain José, Tarifeño-Saldivia Ariel, Thomas Benedikt, Torres-Sánchez Pablo, Ulrich Jiri, Valenta Stanislav, Vannini Gianni, Variale Vincenzo, Vaz Pedro, Ventura Alberto, Vescovi Diego, Vlachoudis Vasilis, Wallner Anton, Woods Philip-John, Wright Tobias, and Žugec Petar

Subjects
Physics, QC1-999
Abstract

Neutron cross section measurements are often made relative to a neutron cross section standard. Thus, the accuracy of the neutron standards determines the best possible accuracy of the neutron measurements. The 235U(n,f) cross section is widely used as reference, while it is considered a standard at thermal point and between 0.15 to 200 MeV. For this reason, additional cross section data for the 235U(n,f) reaction are useful in order to improve the accuracy and to extend the energy range of the standard. In this work, preliminary results of the measurement of the 235U(n,f) cross-section relative to the standard 10B(n,a) reaction are presented. The high accuracy measurement was performed at the experimental area EAR-1 of the n_TOF facility at CERN, aiming at covering the energy range from the thermal region up to approximately 100 keV. The samples were produced at JRC-Geel in Belgium, while the experimental setup was based on Micromegas detectors.

Published
2023
Full Text
View/download PDF

5. On the interplay of liquid-like and stress-driven dynamics in a metallic glass former observed by temperature scanning XPCS

Author

Frey, Maximilian, Neuber, Nico, Riegler, Sascha Sebastian, Cornet, Antoine, Chushkin, Yuriy, Zontone, Federico, Ruschel, Lucas, Adam, Bastian, Nabahat, Mehran, Yang, Fan, Shen, Jie, Westermeier, Fabian, Sprung, Michael, Cangialosi, Daniele, Di Lisio, Valerio, Gallino, Isabella, Busch, Ralf, Ruta, Beatrice, and Pineda, Eloi

Subjects
Condensed Matter - Materials Science, Condensed Matter - Soft Condensed Matter
Abstract

Modern detector technology and highly brilliant fourth-generation synchrotrons allow to improve the temporal resolution in time-resolved diffraction studies. Profiting from this, we applied temperature scanning X-ray photon correlation spectroscopy (XPCS) to probe the dynamics of a Pt-based metallic glass former in the glass, glass transition region, and supercooled liquid, covering up to six orders of magnitude in time scales. Our data demonstrates that the structural alpha-relaxation process is still observable in the glass, although it is partially masked by a faster source of decorrelation observed at atomic scale. We present an approach that interprets these findings as the superposition of heterogeneous liquid-like and stress-driven ballistic-like atomic motions. This work not only extends the dynamical range probed by standard isothermal XPCS, but also clarifies the fate of the alpha-relaxation across the glass transition and provides a new perception on the anomalous, compressed temporal decay of the density-density correlation functions observed in metallic glasses and many out-of-equilibrium soft materials.

Published
2024

6. European Society of Intensive Care Medicine guidelines on end of life and palliative care in the intensive care unit

Author

Kesecioglu, Jozef, Rusinova, Katerina, Alampi, Daniela, Arabi, Yaseen M., Benbenishty, Julie, Benoit, Dominique, Boulanger, Carole, Cecconi, Maurizio, Cox, Christopher, van Dam, Marjel, van Dijk, Diederik, Downar, James, Efstathiou, Nikolas, Endacott, Ruth, Galazzi, Alessandro, van Gelder, Fiona, Gerritsen, Rik T., Girbes, Armand, Hawyrluck, Laura, Herridge, Margaret, Hudec, Jan, Kentish-Barnes, Nancy, Kerckhoffs, Monika, Latour, Jos M., Malaska, Jan, Marra, Annachiara, Meddick-Dyson, Stephanie, Mentzelopoulos, Spyridon, Mer, Mervyn, Metaxa, Victoria, Michalsen, Andrej, Mishra, Rajesh, Mistraletti, Giovanni, van Mol, Margo, Moreno, Rui, Nelson, Judith, Suñer, Andrea Ortiz, Pattison, Natalie, Prokopova, Tereza, Puntillo, Kathleen, Puxty, Kathryn, Qahtani, Samah Al, Radbruch, Lukas, Rodriguez-Ruiz, Emilio, Sabar, Ron, Schaller, Stefan J., Siddiqui, Shahla, Sprung, Charles L., Umbrello, Michele, Vergano, Marco, Zambon, Massimo, Zegers, Marieke, Darmon, Michael, and Azoulay, Elie

Published
2024
Full Text
View/download PDF

9. First 80Se(n,γ) cross section measurement with high resolution in the full stellar energy range 1 eV - 100 keV and its astrophysical implications for the s-process

Author

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

Subjects
Physics, QC1-999
Abstract

Most elements heavier than iron have been generated in the stellar media by means of neutron capture reactions, approximately half are produced by the slow neutron capture or s-process. Radiative neutron capture cross section measurements are of fundamental importance for the study of this mechanism. In this contribution we present a brief summary on the measurement and results for the 80Se(n,γ) cross-section. The experiment was carried out at CERN n_TOF EAR1 via the time of flight (ToF) technique, using four C6D6 scintillation detectors with very fast response. More than a hundred new resonances have been analyzed for the first time with a high accuracy. The MACS obtained at kT = 8 keV is 36% smaller than the recommended value in KADo-NiS. Some of the astrophysical implications of this result are elucidated in this contribution.

Published
2022
Full Text
View/download PDF

10. High pressure X-Ray Photon Correlation Spectroscopy at 4th generation synchrotron sources

Author

Cornet, Antoine, Ronca, Alberto, Shen, Jie, Zontone, Federico, Chushkin, Yuriy, Cammarata, Marco, Garbarino, Gaston, Sprung, Michael, Westermaier, Fabian, Deschamps, Thierry, and Ruta, Beatrice

Subjects
Physics - Applied Physics, Condensed Matter - Materials Science
Abstract

A new experimental setup combining X-Ray Photon Correlation Spectroscopy (XPCS) in the hard x-ray regime and a high-pressure sample environment is developed to monitor the pressure dependence of the internal motion of complex systems down to the atomic scale in the multi-GPa range, from room temperature to 600K. The high flux of coherent high energy x-rays at 4th generation synchrotron source solves the problems caused by the absorption of the Diamond Anvil Cells used to generate the high pressure, enabling the measurement of the intermediate scattering function over 6 orders of magnitude in time, from $10^{-3}$ s to $10^{3}$s. The constraints posed by the high-pressure generation such as the preservation of the x-ray's coherence, as well as the sample, pressure and temperature stability are discussed, and the feasibility of high pressure XPCS is demonstrated through results obtained on metallic glasses.

Published
2024

12. On the signed Selmer groups for motives at non-ordinary primes in $\mathbb{Z}_p^2$-extensions

Author

Ray, Jishnu and Sprung, Florian

Subjects
Mathematics - Number Theory, primary: 11R23, Secondary: 11G10, 11R20
Abstract

Generalizing the work of Kobayashi and the second author for elliptic curves with supersingular reduction at the prime $p$, B\"uy\"ukboduk and Lei constructed multi-signed Selmer groups over the cyclotomic $\mathbb{Z}_p$-extension of a number field $F$ for more general non-ordinary motives. In particular, their construction applies to abelian varieties over $F$ with good supersingular reduction at all the primes of $F$ above $p$. In this article, we scrutinize the case in which $F$ is imaginary quadratic, and prove a control theorem (that generalizes Kim's control theorem for elliptic curves) of multi-signed Selmer groups of non-ordinary motives over the maximal abelian pro-$p$ extension of $F$ that is unramified outside $p$, which is the $\mathbb{Z}_p^2$-extension of $F$. We apply it to derive a sufficient condition when these multi-signed Selmer groups are cotorsion over the corresponding two-variable Iwasawa algebra. Furthermore, we compare the Iwasawa $\mu$-invariants of multi-signed Selmer groups over the $\mathbb{Z}_p^2$-extension for two such representations which are congruent modulo $p$.

Published
2023

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

Author

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

Subjects
Physics, QC1-999
Abstract

Although the 12C(n,p)12B and 12C(n,d)11B reactions are of interest in several fields of basic and applied Nuclear Physics the present knowledge of these two cross-sections is far from being accurate and reliable, with both evaluations and data showing sizable discrepancies. As part of the challenging n_TOF program on (n,cp) nuclear reactions study, the energy differential cross-sections of the 12C(n,p)12B and 12C(n,d)11 B reactions have been measured at CERN from the reaction thresholds up to 30 MeV neutron energy. Both measurements have been recently performed at the long flight-path (185 m) experimental area of the n_TOF facility at CERN using a pure (99.95%) rigid graphite target and two silicon telescopes. In this paper an overview of the experiment is presented together with a few preliminary results.

Published
2020
Full Text
View/download PDF

14. First results of the 241Am(n,f) cross section measurement at the Experimental Area 2 of the n_TOF facility at CERN

Author

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

Subjects
Physics, QC1-999
Abstract

Feasibility, design and sensitivity studies on innovative nuclear reactors that could address the issue of nuclear waste transmutation using fuels enriched in minor actinides, require high accuracy cross section data for a variety of neutron-induced reactions from thermal energies to several tens of MeV. The isotope 241Am (T1/2= 433 years) is present in high-level nuclear waste (HLW), representing about 1.8 % of the actinide mass in spent PWR UOx fuel. Its importance increases with cooling time due to additional production from the β-decay of 241Pu with a half-life of 14.3 years. The production rate of 241 Am in conventional reactors, including its further accumulation through the decay of 241Pu and its destruction through transmutation/incineration are very important parameters for the design of any recycling solution. In the present work, the 241 Am(n,f) reaction cross-section was measured using Micromegas detectors at the Experimental Area 2 of the n_TOF facility at CERN. For the measurement, the 235U(n,f) and 238U(n,f) reference reactions were used for the determination of the neutron flux. In the present work an overview of the experimental setup and the adopted data analysis techniques is given along with preliminary results.

Published
2020
Full Text
View/download PDF

15. Status and perspectives of the neutron time-of-flight facility n_TOF at CERN

Author

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

Subjects
Physics, QC1-999
Abstract

Since the start of its operation in 2001, based on an idea of Prof. Carlo Rubbia [1], the neutron time of-flight facility of CERN, n_TOF, has become one of the most forefront neutron facilities in the world for wide-energy spectrum neutron cross section measurements. Thanks to the combination of excellent neutron energy resolution and high instantaneous neutron flux available in the two experimental areas, the second of which has been constructed in 2014, n_TOF is providing a wealth of new data on neutron-induced reactions of interest for nuclear astrophysics, advanced nuclear technologies and medical applications. The unique features of the facility will continue to be exploited in the future, to perform challenging new measurements addressing the still open issues and long-standing quests in the field of neutron physics. In this document the main characteristics of the n_TOF facility and their relevance for neutron studies in the different areas of research will be outlined, addressing the possible future contribution of n_TOF in the fields of nuclear astrophysics, nuclear technologies and medical applications. In addition, the future perspectives of the facility will be described including the upgrade of the spallation target, the setup of an imaging installation and the construction of a new irradiation area.

Published
2020
Full Text
View/download PDF

16. The 154Gd neutron capture cross section measured at the n_TOF facility and its astrophysical implications

Author

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

Subjects
Physics, QC1-999
Abstract

The (n, γ) cross sections of the gadolinium isotopes play an important role in the study of the stellar nucleosynthesis. In particular, among the isotopes heavier than Fe, 154Gd together with 152Gd have the peculiarity to be mainly produced by the slow capture process, the so-called s-process, since they are shielded against the β-decay chains from the r-process region by their stable samarium isobars. Such a quasi pure s-process origin makes them crucial for testing the robustness of stellar models in galactic chemical evolution (GCE). According to recent models, the 154Gd and 152Gd abundances are expected to be 15-20% lower than the reference un-branched s-process 150Sm isotope. The close correlation between stellar abundances and neutron capture cross sections prompted for an accurate measurement of 154Gd cross section in order to reduce the uncertainty attributable to nuclear physics input and eventually rule out one of the possible causes of present discrepancies between observation and model predictions. To this end, the neutron capture cross section of 154Gd was measured in a wide neutron energy range (from thermal up to some keV) with high resolution in the first experimental area of the neutron time-of-flight facility n_TOF (EAR1) at CERN. In this contribution, after a brief description of the motivation and of the experimental setup used in the measurement, the preliminary results of the 154Gd neutron capture reaction as well as their astrophysical implications are presented.

Published
2020
Full Text
View/download PDF

17. Setup for the measurement of the 235U(n, f) cross section relative to n-p scattering up to 1 GeV

Author

Manna A., Aberle O., Alcayne V, Amaducci S., Andrzejewski J., Audouin L., Babiano V-Suarez, Bacak M., Barbagallo M., Bennett S., Berthoumieux E., Bosnar D., Brown A. S., Busso M., Caamaño M., Caballero L., Calviani M., Calvi Fño, Cano-Ott D, Casanovas A., Cerutti F., Chiaveri E., Colonna N., Cortés G. P., Cortés-Giraldo M. A., Coséntino L., Cristallo S., Damone L. A., Davies P. J., Diakaki M., Dietz M., Domingo-Pardo C, Dressler R., Ducasse Q., Dupont E., Durán I., Eleme Z., Fernández-Domíngez B., Ferrari A., Ferro-Goncalves I, Finocchiaro P., Furman V., Garg R., Gawlik A., Gilardoni S., Göbel K., González-Romero E., Guerrero C., Gunsing F, Heinitz S., Heyse J., Jenkins D. G., Jericha E., Jiri U., Junghans A., Kadi Y, Käppeler F, Kimura A., Knapová I., Kokkoris M., Kopatch Y., Krtiička M., Kurtulgil D., Ladarescu I., Lederer-Woods C, Lerendegui-Marco J, Lonsdale S.-J., Macina D., Martínez T, Masi A., Massimi C., Mastinu P. F, Mastromarco M., Maugeri E., Mazzone A., Mendoza E., Mengoni A., Michalopoulou V, Milazzo P. M., Millán-Callado M. A., Mingrone F, Moreno-Soto J, Musumarra A., Negret A., Nolte R., Ogállar F, Oprea A., Patronis N., Pavlik A., Perkowski J., Petrone C., Piersanti L., Pirovano E., Porras I., Praena J., Quesada J.M., Ramos D., Reifarth R., Rochman D., Rubbia C., Sabaté-Gilarte M., Saxena A., Schillebeeckx P., Schumann D., Sekhar A., Smith A.G., Sosnin N., Sprung P., Stamatopoulos A., Tagliente G., Tain J. L., Tarifeno-Saldivia A. E., Tassan-Got L, Thomas B., Torres-Sánchez P., Tsinganis A., Urlass S., Valenta S., Vannini G., Variale V., Vaz P., Ventura A., Vescovi D., Vlachoudis V, Vlastou R., Wallner A., Woods P. J., Wright T J., and Žugec P.

Subjects
Physics, QC1-999
Abstract

The neutron induced fission of 235U is extensively used as a reference for neutron fluence measurements in various applications, ranging from the investigation of the biological effectiveness of high energy neutrons, to the measurement of high energy neutron cross sections of relevance for accelerator driven nuclear systems. Despite its widespread use, no data exist on neutron induced fission of 235U above 200 MeV. The neutron facility n_TOF offers the possibility to improve the situation. The measurement of 235U(n,f) relative to the differential n-p scattering cross-section, was carried out in September 2018 with the aim of providing accurate and precise cross section data in the energy range from 10 MeV up to 1 GeV. In such measurements, Recoil Proton Telescopes (RPTs) are used to measure the neutron flux while the fission events are detected and counted with dedicated detectors. In this paper the measurement campaign and the experimental set-up are illustrated.

Published
2020
Full Text
View/download PDF

18. New reaction rates for the destruction of 7Be during big bang nucleosynthesis measured at CERN/n_TOF and their implications on the cosmological lithium problem

Author

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

Subjects
Physics, QC1-999
Abstract

New measurements of the 7Be(n,α)4He and 7Be(n,p)7Li reaction cross sections from thermal to keV neutron energies have been recently performed at CERN/n_TOF. Based on the new experimental results, astrophysical reaction rates have been derived for both reactions, including a proper evaluation of their uncertainties in the thermal energy range of interest for big bang nucleosynthesis studies. The new estimate of the 7Be destruction rate, based on these new results, yields a decrease of the predicted cosmological 7Li abundance insufficient to provide a viable solution to the cosmological lithium problem.

Published
2020
Full Text
View/download PDF

19. Monte Carlo simulations and n-p differential scattering data measured with Proton Recoil Telescopes

Author

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

Subjects
Physics, QC1-999
Abstract

The neutron-induced fission cross section of 235U, a standard at thermal energy and between 0.15 MeV and 200 MeV, plays a crucial role in nuclear technology applications. The long-standing need of improving cross section data above 20 MeV and the lack of experimental data above 200 MeV motivated a new experimental campaign at the n_TOF facility at CERN. The measurement has been performed in 2018 at the experimental area 1 (EAR1), located at 185 m from the neutron-producing target (the experiment is presented by A. Manna et al. in a contribution to this conference). The 235U(n,f) cross section from 20 MeV up to about 1 GeV has been measured relative to the 1H(n,n)1H reaction, which is considered the primary reference in this energy region. The neutron flux impinging on the 235U sample (a key quantity for determining the fission events) has been obtained by detecting recoil protons originating from n-p scattering in a C2H4 sample. Two Proton Recoil Telescopes (PRT), consisting of several layers of solid-state detectors and fast plastic scintillators, have been located at proton scattering angles of 25.07° and 20.32°, out of the neutron beam. The PRTs exploit the ΔE-E technique for particle identification, a basic requirement for the rejection of charged particles from neutron-induced reactions in carbon. Extensive Monte Carlo simulations were performed to characterize proton transport through the different slabs of silicon and scintillation detectors, to optimize the experimental set-up and to deduce the efficiency of the whole PRT detector. In this work we compare measured data collected with the PRTs with a full Monte Carlo simulation based on the Geant-4 toolkit.

Published
2020
Full Text
View/download PDF

20. First results of the 230Th(n,f) cross section measurements at the CERN n_TOF facility

Author

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

Subjects
Physics, QC1-999
Abstract

The study of neutron-induced reactions on actinides is of considerable importance for the design of advanced nuclear systems and alternative fuel cycles. Specifically, 230Th is produced from the α-decay of 234U as a byproduct of the 232Th/233U fuel cycle, thus the accurate knowledge of its fission cross section is strongly required. However, few experimental datasets exist in literature with large deviations among them, covering the energy range between 0.2 to 25 MeV. In addition, the study of the 230Th(n,f) cross-section is of great interest in the research on the fission process related to the structure of the fission barriers. Previous measurements have revealed a large resonance at En=715 keV and additional fine structures, but with high discrepancies among the cross-section values of these measurements. This contribution presents preliminary results of the 230Th(n,f) cross-section measurements at the CERN n_TOF facility. The high purity targets of the natural, but very rare isotope 230Th, were produced at JRC-Geel in Belgium. The measurements were performed at both experimental areas (EAR-1 and EAR-2) of the n_TOF facility, covering a very broad energy range from thermal up to at least 100 MeV. The experimental setup was based on Micromegas detectors with the 235U(n,f) and 238U(n,f) reaction cross-sections used as reference.

Published
2020
Full Text
View/download PDF

26. Cotorsion of anti-cyclotomic Selmer groups on average

Author

Kundu, Debanjana and Sprung, Florian

Subjects
Mathematics - Number Theory
Abstract

For an elliptic curve, we study how many Selmer groups are cotorsion over the anti-cyclotomic $\mathbb{Z}_p$-extension as one varies the prime $p$ or the quadratic imaginary field in question., Comment: 12+epsilon pages, comments very welcome

Published
2023

27. Interplay between atomic fluctuations and charge density waves in La$_{2-x}$Sr$_{x}$CuO$_{4}$

Author

Shen, L., Esposito, V., Burdet, N. G., Zhu, M., Petsch, A. N., Croft, T. P., Collins, S. P., Ren, Z., Westermeier, F., Sprung, M., Hayden, S. M., Turner, J. J., and Blackburn, E.

Subjects
Condensed Matter - Superconductivity, Condensed Matter - Materials Science, Condensed Matter - Strongly Correlated Electrons
Abstract

In the cuprate superconductors, the spatial coherence of the charge density wave (CDW) state grows rapidly below a characteristic temperature $T_\mathrm{CDW}$, the nature of which is debated. We have combined a set of x-ray scattering techniques to study La$_{1.88}$Sr$_{0.12}$CuO$_{4}$ ($T_\mathrm{CDW}$~$\approx$~80\,K) to shed light on this discussion. We observe the emergence of a crystal structure, which is consistent with the CDW modulation in symmetry, well above $T_\mathrm{CDW}$. This global structural change also induces strong fluctuations of local atomic disorder in the intermediate temperature region. At $T_\mathrm{CDW}$, the temperature dependence of this structure develops a kink, while the atomic disorder is minimized. We find that the atomic relaxation dynamics cross over from a cooperative to an incoherent response at $T_\mathrm{CDW}$. These results reveal a rich interplay between the CDWs and atomic fluctuations of distinct spatio-temporal scales. For example, the CDW coherence is enhanced on quasi-elastic timescales by incoherent atomic relaxation.

Published
2023
Full Text
View/download PDF

28. A Systematic Approach to Automotive Security

Author

Ebrahimi, Masoud, Marksteiner, Stefan, Ničković, Dejan, Bloem, Roderick, Schögler, David, Eisner, Philipp, Sprung, Samuel, Schober, Thomas, Chlup, Sebastian, Schmittner, Christoph, and König, Sandra

Subjects
Computer Science - Cryptography and Security
Abstract

We propose a holistic methodology for designing automotivesystems that consider security a central concern at every design stage.During the concept design, we model the system architecture and definethe security attributes of its components. We perform threat analysis onthe system model to identify structural security issues. From that analysis,we derive attack trees that define recipes describing steps to successfullyattack the system's assets and propose threat prevention measures.The attack tree allows us to derive a verification and validation (V&V)plan, which prioritizes the testing effort. In particular, we advocate usinglearning for testing approaches for the black-box components. It consistsof inferring a finite state model of the black-box component from its executiontraces. This model can then be used to generate new relevanttests, model check it against requirements, and compare two differentimplementations of the same protocol. We illustrate the methodologywith an automotive infotainment system example. Using the advocated approach, we could also document unexpected and potentially criticalbehavior in our example systems., Comment: Presented at Formal Methods 2023 25th International Symposium (FM'23). 12 pages, 5 figures

Published
2023
Full Text
View/download PDF

29. Study of the photon strength functions and level density in the gamma decay of the n + 234U reaction

Author

Moreno-Soto J., Berthoumieux E, Dupont E, Gunsing F, Serot O, Litaize O, Diakaki M, Chebboubi A, Dridi W, Valenta S, Krtiˇcka M., Aberle O, Alcayne V, Andrzejewski J, Audouin L, Bécares V., Babiano-Suarez V., Bacak M, Barbagallo M, Benedikt Th, Bennett S, Billowes J, Bosnar D, Brown A, Busso M, Caamaño M., Caballero-Ontanaya L., Calviño F., Calviani M, Cano-Ott D., Casanovas A, Cerutti F, Chiaveri E, Colonna N, Cortés G., Cortés-Giraldo M. A., Cosentino L, Cristallo S, Damone L. A, Davies P. J, Dietz M, Domingo-Pardo C., Dressler R, Ducasse Q, Durán I., Eleme Z, Fernández-Domínguez B., Ferrari A, Finocchiaro P, Furman V, Göbel K., Gawlik A, Gilardoni S, Gonçalves I. F., González-Romero E., Guerrero C, Heinitz S, Heyse J, Jenkins D. G, Junghans A, Käppeler F., Kadi Y, Kimura A, Knapova I, Kokkoris M, Kopatch Y, Kurtulgil D, Ladarescu I, Lederer-Woods C., Lonsdale S. J, Macina D, Manna A, Martínez T., Masi A, Massimi C, Mastinu P, Mastromarco M, Maugeri E. A, Mazzone A, Mendoza E, Mengoni A, Michalopoulou V, Milazzo P. M, Mingrone F, Musumarra A, Negret A, Ogállar F., Oprea A, Patronis N, Pavlik A, Perkowski J, Persanti L, Petrone C, Pirovano E, Porras I, Praena J, Quesada J. M, Ramos-Doval D., Rauscher T, Reifarth R, Rochman D, Sabaté-Gilarte M., Saxena A, Schillebeeckx P, Schumann D, Sekhar A, Simone S, Smith A. G, Sosnin N. V, Sprung P, Stamatopoulos A, Tagliente G, Tain J. L, Tarifeño-Saldivia A., Tassan-Got L., Tsinganis A, Ulrich J, Urlass 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 accurate calculations of neutron-induced reaction cross sections are relevant for many nuclear applications. The photon strength functions and nuclear level densities are essential inputs for such calculations. These quantities for 235U are studied using the measurement of the gamma de-excitation cascades in radiative capture on 234U with the Total Absorption Calorimeter at n_TOF at CERN. This segmented 4π gamma calorimeter is designed to detect gamma rays emitted from the nucleus with high efficiency. This experiment provides information on gamma multiplicity and gamma spectra that can be compared with numerical simulations. The code DICEBOXC is used to simulate the gamma cascades while GEANT4 is used for the simulation of the interaction of these gammas with the TAC materials. Available models and their parameters are being tested using the present data. Some preliminary results of this ongoing study are presented and discussed.

Published
2019
Full Text
View/download PDF

30. Fission program at n_TOF

Author

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

Subjects
Physics, QC1-999
Abstract

Since its start in 2001 the n_TOF collaboration developed a measurement program on fission, in view of advanced fuels in new generation reactors. A special effort was made on measurement of cross sections of actinides, exploiting the peculiarity of the n_TOF neutron beam which spans a huge energy domain, from the thermal region up to GeV. Moreover fission fragment angular distributions have also been measured. An overview of the cross section results achieved with different detectors is presented, including a discussion of the 237Np case where discrepancies showed up between different detector systems. The results on the anisotropy of the fission fragments and its implication on the mechanism of neutron absorption, and in applications, are also shown.

Published
2019
Full Text
View/download PDF

31. Coherent X-ray Scattering Reveals Nanoscale Fluctuations in Hydrated Proteins

Author

Bin, Maddalena, Reiser, Mario, Filianina, Mariia, Berkowicz, Sharon, Das, Sudipta, Timmermann, Sonja, Roseker, Wojciech, Bauer, Robert, Öström, Jonatan, Karina, Aigerim, Amann-Winkel, Katrin, Ladd-Parada, Marjorie, Westermeier, Fabian, Sprung, Michael, Möller, Johannes, Lehmkühler, Felix, Gutt, Christian, and Perakis, Fivos

Subjects
Condensed Matter - Soft Condensed Matter, Physics - Biological Physics, Physics - Chemical Physics
Abstract

Hydrated proteins undergo a transition in the deeply supercooled regime, which is attributed to rapid changes in hydration water and protein structural dynamics. Here, we investigate the nanoscale stress relaxation in hydrated lysozyme proteins stimulated and probed by X-ray Photon Correlation Spectroscopy (XPCS). This approach allows us to access the nanoscale dynamic response in the deeply supercooled regime (T = 180 K) which is typically not accessible through equilibrium methods. The relaxation time constants exhibit Arrhenius temperature dependence upon cooling with a minimum in the Kohlrausch-Williams-Watts exponent at T = 227 K. The observed minimum is attributed to an increase in dynamical heterogeneity, which coincides with enhanced fluctuations observed in the two-time correlation functions and a maximum in the dynamic susceptibility quantified by the normalised variance $\chi_T$. Our study provides new insights into X-ray stimulated stress relaxation and the underlying mechanisms behind spatio-temporal fluctuations in biological granular materials.

Published
2023
Full Text
View/download PDF

32. Mapping the 3D position of battery cathode particles in Bragg coherent diffractive imaging.

Author

Shabalin, A, Zhang, M, Yao, W, Rysov, R, Ren, Z, Lapkin, D, Kim, Y, Assalauova, D, Mukharamova, N, Sprung, M, Vartanyants, I, Meng, Y, and Shpyrko, O

Subjects
3D mapping, Bragg coherent X-ray diffractive imaging, Bragg diffraction, battery cathodes, extra-thick battery cathodes, sphere of confusion
Abstract

In Bragg coherent diffractive imaging, the precise location of the measured crystals in the interior of the sample is usually missing. Obtaining this information would help the study of the spatially dependent behavior of particles in the bulk of inhomogeneous samples, such as extra-thick battery cathodes. This work presents an approach to determine the 3D position of particles by precisely aligning them at the instrument axis of rotation. In the test experiment reported here, with a 60 µm-thick LiNi0.5Mn1.5O4 battery cathode, the particles were located with a precision of 20 µm in the out-of-plane direction, and the in-plane coordinates were determined with a precision of 1 µm.

Published
2023

33. La matrice de logarithme en termes de chiffres $p$-adiques (The logarithm matrix in terms of $p$-adic digits)

Author

Sprung, Florian

Subjects
Mathematics - Number Theory
Abstract

Nous donnons une nouvelle description de la matrice de logarithme d'une forme modulaire en termes de distributions, g\'en\'eralisant le travail de Dion et Lei pour le cas $a_p=0$. Ce qui nous permet d'inclure le cas $a_p\ne 0$ est une nouvelle d\'efinition, celle d'une matrice de distributions, et la caract\'erisation de cette matrice par de chiffres $p$-adiques. On peut appliquer ces m\'ethodes au cas correspondant d'une distribution \`a plusieurs variables. -- We give a new description of the logarithm matrix of a modular form in terms of distributions, generalizing the work of Dion and Lei for the case $a_p=0$. What allows us to include the case $a_p\ne 0$ is a new definition, that of a distribution matrix, and the characterization of this matrix by $p$-adic digits. One can apply these methods to the corresponding case of distributions in multiple variables., Comment: 6 pages, in French language. Comments very welcome!

Published
2022

34. Disentangling structural and kinetic components of the {\alpha}-relaxation in supercooled metallic liquids

Author

Neuber, Nico, Gross, Oliver, Frey, Maximilian, Bochtler, Benedikt, Kuball, Alexander, Hechler, Simon, Yang, Fan, Pineda, Eloi, Westermeier, Fabian, Sprung, Michael, Gallino, Isabella, Busch, Ralf, and Ruta, Beatrice

Subjects
Condensed Matter - Materials Science, Condensed Matter - Disordered Systems and Neural Networks
Abstract

The particle motion associated to the {\alpha}-relaxation in supercooled liquids is still challenging scientists due to its difficulty to be probed experimentally. By combining synchrotron techniques, we found the existence of microscopic structure-dynamics relationships in Pt42.5Cu27Ni9.5P21 and Pd42.5Cu27Ni9.5P21 liquids which allows us to disentangle structural and kinetic contributions to the {\alpha}-process. While the two alloys show similar kinetic fragilities, their structural fragilities differ and correlate with the temperature dependence of the stretching parameter describing the decay of the density fluctuations. This implies that the evolution of dynamical heterogeneities in supercooled alloys is determined by the rigidity of the melt structure. We find also that the atomic motion not only reflects the topological order but also the chemical short-range order, which can lead to a surprising slowdown of the {\alpha}-process at the mesoscopic length scale. These results will contribute to the comprehension of the glass transition, which is still missing.

Published
2022

37. Studying Hilbert's 10th problem via explicit elliptic curves

Author

Kundu, Debanjana, Lei, Antonio, and Sprung, Florian

Subjects
Mathematics - Number Theory, Mathematics - Logic
Abstract

N.Garc\'ia-Fritz and H.Pasten showed that Hilbert's 10th problem is unsolvable in the ring of integers of number fields of the form $\mathbb{Q}(\sqrt[3]{p},\sqrt{-q})$ for positive proportions of primes $p$ and $q$. We improve their proportions and extend their results to the case of number fields of the form $\mathbb{Q}(\sqrt[3]{p},\sqrt{Dq})$, where $D$ belongs to an explicit family of positive square-free integers. We achieve this by using multiple elliptic curves, and replace their Iwasawa theory arguments by a more direct method., Comment: Comments very welcome!

Published
2022

38. Strain and Crystallographic Identification of the Helically Concaved Surfaces of Nanoparticles

Author

Choi, Sungwook, Im, Sang Won, Huh, Ji-Hyeok, Kim, Sungwon, Kim, Jaeseung, Lim, Yae-Chan, Kim, Ryeong Myeong, Han, Jeong Hyun, Kim, Hyeohn, Sprung, Michael, Lee, Su Yong, Cha, Wonsuk, Harder, Ross, Lee, Seungwoo, Nam, Ki Tae, and Kim, Hyunjung

Subjects
Condensed Matter - Materials Science
Abstract

Identifying the three-dimensional (3D) crystal-plane and strain-field distributions of nanocrystals is essential for optical, catalytic, and electronic applications. Here, we developed a methodology for visualizing the 3D information of chiral gold nanoparticles with concave gap structures by Bragg coherent X-ray diffraction imaging. The distribution of the high-Miller-index planes constituting the concave chiral gap was precisely determined. The highly strained region adjacent to the chiral gaps was resolved, which was correlated to the 432-symmetric morphology of the nanoparticles and its corresponding plasmonic properties were numerically predicted from the atomically defined structures. This approach can serve as a general characterization platform for visualizing the 3D crystallographic and strain distributions of nanoparticles, especially for applications where structural complexity and local heterogeneity are major determinants, as exemplified in plasmonics., Comment: Sungwook Choi and Sang Won Im contributed equally to this work. Corresponding author. Email: nkitae@snu.ac.kr, hkim@sogang.ac.kr

Published
2022
Full Text
View/download PDF

39. On characteristic power series of dual signed Selmer groups

Author

Ray, Jishnu and Sprung, Florian

Subjects
Mathematics - Number Theory, Primary: 11R23, Secondary: 11R18, 11F11, 11F85
Abstract

We relate the cardinality of the $p$-primary part of the Bloch-Kato Selmer group over $\mathbb{Q}$ attached to a modular form at a non-ordinary prime $p$ to the constant term of the characteristic power series of the signed Selmer groups over the cyclotomic $\mathbb{Z}_p$-extension of $\mathbb{Q}$. This generalizes a result of Vigni and Longo in the ordinary case. In the case of elliptic curves, such results follow from earlier works by Greenberg, Kim, the second author, and Ahmed-Lim, covering both the ordinary and most of the supersingular case., Comment: Accepted in Annales de l'Institut Fourier

Published
2022

40. Nanoscale inhomogeneity of charge density waves dynamics in La$_{2-x}$Sr$_x$NiO$_4$

Author

Campi, Gaetano, Bianconi, Antonio, Joseph, Boby, Mishra, Shrawan Kr, Muller, Leonard, Zozulya, Alexey, Nugroho, Agustinus Agung, Roy, Sujoy, Sprung, Michael, and Ricci, Alessandro

Subjects
Condensed Matter - Strongly Correlated Electrons, Condensed Matter - Superconductivity, Quantum Physics
Abstract

While stripe phases with broken rotational symmetry of charge density appear in many complex correlated systems, the heterogeneity of spatial ordering and dynamics remains elusive. This missing info is at the heart of understanding the structure and function relation in quantum complex materials. We focus here on the spatial heterogeneity of the motion of charge density wave (CDW) at nanoscale in the archetypal case of La$_{2-x}$Sr$_x$NiO$_{4+y}$ perovskite at low temperature. We report compelling evidence that the unconventional increasing motion of CDW at T < 50K is related with the decreasing of its correlation length using resonant soft X-ray photon correlation spectroscopy (XPCS). The key result of this work is the direct visualization of nanoscale spatial inhomogeneity of CDW relaxation dynamics by scanning micro X-ray diffraction (SmXRD) showing a nanoscale landscape of percolating short range dynamic CDW puddles competing with large quasi-static CDW puddles giving rise to a novel form of nanoscale phase separation of the incommensurate stripes order landscape., Comment: 15 pages, 3 figures

Published
2022
Full Text
View/download PDF

41. Angular X-ray Cross-Correlation Analysis Applied to the Scattering Data in 3D Reciprocal Space from a Single Crystal

Author

Lapkin, Dmitry, Shabalin, Anatoly, Meijer, Janne-Mieke, Kurta, Ruslan, Sprung, Michael, Petukhov, Andrei V., and Vartanyants, Ivan A.

Subjects
Condensed Matter - Mesoscale and Nanoscale Physics, Condensed Matter - Materials Science
Abstract

We propose an application of the Angular X-ray Cross-Correlation Analysis (AXCCA) to the scattered intensity distribution measured in three-dimensional (3D) reciprocal space from a single crystalline sample. Contrary to the conventional application of AXCCA, when averaging over many two-dimensional (2D) diffraction patterns collected from different randomly oriented samples is required, the proposed approach gives an insight into the structure of a single specimen. This is particularly useful in studies of defect-reach samples that are unlikely to have the same structure. Here, we demonstrate an example of a qualitative structure determination of a colloidal crystal on the simulated as well as experimentally measured 3D scattered intensity distributions., Comment: 37 pages, 9 figures

Published
2022

47. In-situ Characterization of Crystallization and Melting of Soft, Thermoresponsive Microgels by Small-Angle X-ray Scattering

Author

Lapkin, Dmitry, Mukharamova, Nastasia, Assalauova, Dameli, Dubinina, Svetlana, Stellhorn, Jens, Westermeier, Fabian, Lazarev, Sergey, Sprung, Michael, Karg, Matthias, Vartanyants, Ivan A., and Meijer, Janne-Mieke

Subjects
Condensed Matter - Soft Condensed Matter
Abstract

Depending on the volume fraction and interparticle interactions, colloidal suspensions can form different phases, ranging from fluids, crystals, and glasses to gels. For soft microgels that are made from thermoresponsive polymers, the volume fraction can be tuned by temperature, making them excellent systems to experimentally study phase transitions in dense colloidal suspensions. However, investigations of phase transitions at high particle concentration and across the volume phase transition temperature in particular, are challenging due to the deformability and possibility for interpenetration between microgels. Here, we investigate the dense phases of composite core-shell microgels that have a small gold core and a thermoresponsive microgel shell. Employing Ultra Small Angle X-ray Scattering, we make use of the strong scattering signal from the gold cores with respect to the almost negligible signal from the shells. By changing the temperature we study the freezing and melting transitions of the system in-situ. Using Bragg peak analysis and the Williamson-Hall method, we characterize the phase transitions in detail. We show that the system crystallizes into an rhcp structure with different degrees of in-plane and out-of-plane stacking disorder that increase upon particle swelling. We further find that the melting process is distinctly different, where the system separates into two different crystal phases with different melting temperatures and interparticle interactions.

Published
2021

48. Angular structure factor of the hexatic-B liquid crystals: bridging theory and experiment

Author

Zaluzhnyy, Ivan A., Kurta, Ruslan P., Sprung, Michael, Vartanyants, Ivan A., and Ostrovskii, Boris I.

Subjects
Condensed Matter - Soft Condensed Matter
Abstract

We report results from X-ray scattering studies of the angular structure factor of liquid crystal hexatic-B films. According to the sixfold rotational symmetry of the hexatic-B phase, its characteristic scattering splits into six reflections. The shape of the radial and angular cross-sections of these reflections and their temperature evolution are analyzed. We find that over a wide temperature range of the hexatic-B phase existence the angular profiles of the in-plane X-ray scattering are well fitted by the Voigt function, which is a convolution of the Gaussian and Lorentzian functions. This result is supported by the known theoretical considerations of the hexatic structure factor below the smectic-hexatic phase transition temperture. Similar predictions for the angular shape of the hexatic peak in the vicinity of the smectic-hexatic phase transition temperature follow from the multicritical scaling theory of the hexatic-B phase in three dimensions. We find that the specific shape of the hexatic structure factor can be explained by the interplay of two distinct contributions to the free energy of the system, a liquid-like density term and a coupling term between the bond-orientational order and short-range density fluctuations., Comment: 8 pages, 8 figures, 41 references

Published
2021

49. Spatially resolved fluorescence of caesium lead halide perovskite supercrystals reveals quasi-atomic behavior of nanocrystals

Author

Lapkin, Dmitry, Kirsch, Christopher, Hiller, Jonas, Andrienko, Denis, Assalauova, Dameli, Braun, Kai, Carnis, Jerome, Kim, Young Yong, Mandal, Mukunda, Maier, Andre, Meixner, Alfred J., Mukharamova, Nastasia, Scheele, Marcus, Schreiber, Frank, Sprung, Michael, Wahl, Jan, Westendorf, Sophia, Zaluzhnyy, Ivan A., and Vartanyants, Ivan A.

Subjects
Condensed Matter - Materials Science
Abstract

We correlate spatially resolved fluorescence (-lifetime) measurements with X-ray nanodiffraction to reveal surface defects in supercrystals of self-assembled caesium lead halide perovskite nanocrystals and study their effect on the fluorescence properties. Upon comparison with density functional modelling, we show that a loss in structural coherence, an increasing atomic misalignment between adjacent nanocrystals, and growing compressive strain near the surface of the supercrystal are responsible for the observed fluorescence blueshift and decreased fluorescence lifetimes. Such surface defect-related optical properties extend the frequently assumed analogy between atoms and nanocrystals as so-called quasi-atoms. Our results emphasize the importance of minimizing strain during the self-assembly of perovskite nanocrystals into supercrystals for lighting application such as superfluorescent emitters., Comment: 61 pages, 34 figures

Published
2021
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results