P. Vasileiou, T. Mertzimekis, A. Chalil, A. Zyriliou, S. Pelonis, V. Lagaki, G. Siltzovalis, M. Efstathiou, Pavlos Koseoglu, D. Bonatsos, A. Martinou, N. Minkov, N. Mărginean, Constantinescu Mihai, N. Florea, S. Ujeniuc, Andrei Tuturica, C. Costache, R. Mihai, L. Stan, D. Filipescu, S. Toma, I. Gheorghe, I. Dinescu, A. Ionescu, L. Stoica, S. Calinescu, A. Oprea, A. Stoica, C. Sotty, C. Clisu, C. Nita, C. Neascu
This work features preliminary results from a recent experimental campaign at IFIN-HH, Romania, aimed at measuring lifetimes of excited states in the neutron-rich 180Hf, by means of the RDDS technique. The 181Ta(11B,12C)180Hf proton pick-up reaction was used to populate excited states in the 180Hf nucleus. The ROSPHERE array loaded with 25 HPGe detectors was employed for the detection of the γ transitions depopulating the levels of interest. The array was coupled to the SORCERER particle detector and a plunger device enabling the study of p-γ and p-γ-γ coinciding events. Six different plunger foil distances were chosen, allowing for the construction of the decay curves of the observed γ transitions of interest, from which the corresponding level lifetimes can subsequently be deduced.
{"title":"Experimental Study of the Nuclear Structure of 180Hf: Preliminary results","authors":"P. Vasileiou, T. Mertzimekis, A. Chalil, A. Zyriliou, S. Pelonis, V. Lagaki, G. Siltzovalis, M. Efstathiou, Pavlos Koseoglu, D. Bonatsos, A. Martinou, N. Minkov, N. Mărginean, Constantinescu Mihai, N. Florea, S. Ujeniuc, Andrei Tuturica, C. Costache, R. Mihai, L. Stan, D. Filipescu, S. Toma, I. Gheorghe, I. Dinescu, A. Ionescu, L. Stoica, S. Calinescu, A. Oprea, A. Stoica, C. Sotty, C. Clisu, C. Nita, C. Neascu","doi":"10.12681/hnps.3612","DOIUrl":"https://doi.org/10.12681/hnps.3612","url":null,"abstract":"This work features preliminary results from a recent experimental campaign at IFIN-HH, Romania, aimed at measuring lifetimes of excited states in the neutron-rich 180Hf, by means of the RDDS technique. The 181Ta(11B,12C)180Hf proton pick-up reaction was used to populate excited states in the 180Hf nucleus. The ROSPHERE array loaded with 25 HPGe detectors was employed for the detection of the γ transitions depopulating the levels of interest. The array was coupled to the SORCERER particle detector and a plunger device enabling the study of p-γ and p-γ-γ coinciding events. Six different plunger foil distances were chosen, allowing for the construction of the decay curves of the observed γ transitions of interest, from which the corresponding level lifetimes can subsequently be deduced.","PeriodicalId":262803,"journal":{"name":"HNPS Advances in Nuclear Physics","volume":"106 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115681988","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
K. Bosmpotinis, M. Kokkoris, A. Lagoyannis, E. Taimpiri, A. Ziagkova
In this study we present the experimental cross sections of the natO(p,p0) elastic scattering, determined via the relative measurement technique, in the proton energy range Elab=4-6 MeV, at six backscattering detector angles between 120o and 170o, with a 10o step. The measurements were performed using the Van de Graaff Tandem 5.5 MV Accelerator of N.C.S.R. “Demokritos” in Athens, Greece and a high precision goniometer.
在这项研究中，我们展示了通过相对测量技术在质子能量范围Elab=4-6 MeV内，在6个反向散射探测器角度在1200 - 170之间，以100步长进行的北约(p,p0)弹性散射的实验截面。在希腊雅典，利用nc.s.r.“Demokritos”的Van de Graaff串联5.5 MV加速器和高精度测角仪进行了测量。
{"title":"Measurement of elastic backscattering differential cross sections for protons on natO in the energy range E= 4-6 MeV, suitable for EBS","authors":"K. Bosmpotinis, M. Kokkoris, A. Lagoyannis, E. Taimpiri, A. Ziagkova","doi":"10.12681/hnps.3714","DOIUrl":"https://doi.org/10.12681/hnps.3714","url":null,"abstract":"In this study we present the experimental cross sections of the natO(p,p0) elastic scattering, determined via the relative measurement technique, in the proton energy range Elab=4-6 MeV, at six backscattering detector angles between 120o and 170o, with a 10o step. The measurements were performed using the Van de Graaff Tandem 5.5 MV Accelerator of N.C.S.R. “Demokritos” in Athens, Greece and a high precision goniometer.","PeriodicalId":262803,"journal":{"name":"HNPS Advances in Nuclear Physics","volume":"8 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115877444","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Zyriliou, T. Mertzimekis, A. Chalil, P. Vasileiou, S. Pelonis, M. Efstathiou, L. Stan, A. Turturica, C. Costache, R. Mihai, R. Borcea, S. Ujeniuc, S. Toma, C. Clisu, A. Oprea, A. Ionescu, I. Gheorghe, M. Boromiza, Constantinescu Mihai, C. Sotty, C. Nita, N. Mărginean, R. Mărginean, N. Florea, I. Dinescu, D. Bucurescu, D. Filipescu, R. Lica, L. Stroe, R. Șuvăilă
The medium-to-heavy mass ytterbium isotopes (70Yb) in the rare-earth mass region are known to be well-deformed nuclei, which can be populated to very high spin, and are predicted to exhibit interesting phenomena, such as shape coexistence. The lack of any experimental information on the structure of the neutron-rich 180Yb isotope and the lifetime of the 21+ state of 178Yb have greatly motivated this study, which can offer useful information for the collective behavior of neutrons and protons in neutron-rich Yb isotopes. A measurement was performed to investigate the population of excited states and a first measurement of the unknown 21+ lifetime of 178Yb by means of a two neutron-transfer reaction 176Yb(18O,16O)178Yb at energies 68-74 MeV using the ROSPHERE array at IFIN-HH, Romania.
{"title":"Nuclear Structure Investigations in Yb isotopes","authors":"A. Zyriliou, T. Mertzimekis, A. Chalil, P. Vasileiou, S. Pelonis, M. Efstathiou, L. Stan, A. Turturica, C. Costache, R. Mihai, R. Borcea, S. Ujeniuc, S. Toma, C. Clisu, A. Oprea, A. Ionescu, I. Gheorghe, M. Boromiza, Constantinescu Mihai, C. Sotty, C. Nita, N. Mărginean, R. Mărginean, N. Florea, I. Dinescu, D. Bucurescu, D. Filipescu, R. Lica, L. Stroe, R. Șuvăilă","doi":"10.12681/hnps.3609","DOIUrl":"https://doi.org/10.12681/hnps.3609","url":null,"abstract":"The medium-to-heavy mass ytterbium isotopes (70Yb) in the rare-earth mass region are known to be well-deformed nuclei, which can be populated to very high spin, and are predicted to exhibit interesting phenomena, such as shape coexistence. The lack of any experimental information on the structure of the neutron-rich 180Yb isotope and the lifetime of the 21+ state of 178Yb have greatly motivated this study, which can offer useful information for the collective behavior of neutrons and protons in neutron-rich Yb isotopes. A measurement was performed to investigate the population of excited states and a first measurement of the unknown 21+ lifetime of 178Yb by means of a two neutron-transfer reaction 176Yb(18O,16O)178Yb at energies 68-74 MeV using the ROSPHERE array at IFIN-HH, Romania.","PeriodicalId":262803,"journal":{"name":"HNPS Advances in Nuclear Physics","volume":"98 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133604308","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. Nikas, A. Kankainen, O. Beliuskina, D. Nesterenko
Nuclear masses are a key aspect in the modelling of nuclear reaction rates for the r-process nucleosynthesis. High precision mass measurements drastically reduce the associated uncertainties in the modelling of r-process nucleosynthesis. We investigate the impact of nuclear mass uncertainties on neutron-capture rates calculations using a Hauser – Feshbach statistical code in the vicinity of 132Sn. Finally, we study the impact of the propagated neutron-capture reaction rates uncertainties on the r-process nucleosynthesis. We find that mass measurements with uncertainties higher than 20 keV affect the calculation of reaction rates. We also note that modelling of reaction rates can differ for more than a factor of two even for experimentally known nuclear masses.
{"title":"Impact of nuclear mass measurements in the vicinity of 132Sn on the r-process nucleosynthesis","authors":"S. Nikas, A. Kankainen, O. Beliuskina, D. Nesterenko","doi":"10.12681/hnps.3605","DOIUrl":"https://doi.org/10.12681/hnps.3605","url":null,"abstract":"Nuclear masses are a key aspect in the modelling of nuclear reaction rates for the r-process nucleosynthesis. High precision mass measurements drastically reduce the associated uncertainties in the modelling of r-process nucleosynthesis. We investigate the impact of nuclear mass uncertainties on neutron-capture rates calculations using a Hauser – Feshbach statistical code in the vicinity of 132Sn. Finally, we study the impact of the propagated neutron-capture reaction rates uncertainties on the r-process nucleosynthesis. We find that mass measurements with uncertainties higher than 20 keV affect the calculation of reaction rates. We also note that modelling of reaction rates can differ for more than a factor of two even for experimentally known nuclear masses.","PeriodicalId":262803,"journal":{"name":"HNPS Advances in Nuclear Physics","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126113373","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A recent example of successful technology transition from high energy physics to practical engineering applications is cosmic ray muon tomography. Cosmic ray muon tomography, is a promising non-destructive technique that has been recently utilized to monitor or image the contents of dense or well shielded objects, typically not feasible with conventional radiography techniques, e.g., x-ray or neutron. Cosmic ray muon tomography has been used with various levels of success in spent nuclear fuel monitoring, volcano imaging, and cargo container imaging. Further, knowledge of cosmic ray muon momentum spectrum has the potential to significantly improve and expand the use of a variety of recently developed muon-based radiographic techniques. However, existing muon tomography systems rely only on muon tracking and have no momentum measurement capabilities which reduces the image resolution and requires longer measurement times. A fieldable cosmic ray muon spectrometer with momentum measurement capabilities for use in muon tomography is currently missing. In this paper, we will discuss and explore recent advances in cosmic ray muon computed tomography and spectroscopy and their applications to engineering including a new concept for measuring muon momentum using multiple gaseous Cherenkov radiators. By varying the pressure of multiple gas Cherenkov radiators, a set of muon momentum threshold levels can be selected that are triggered only when the incoming muon momentum exceeds that level. As a result, depending on the incoming muon momentum, none to all Cherenkov radiators can be triggered. By analyzing the signals from each radiator, we can estimate the actual muon momentum.
{"title":"Advances in Cosmic Ray Muon Computed Tomography and Fieldable Spectroscopy","authors":"S. Chatzidakis, Junghyun Bae","doi":"10.12681/hnps.3584","DOIUrl":"https://doi.org/10.12681/hnps.3584","url":null,"abstract":"A recent example of successful technology transition from high energy physics to practical engineering applications is cosmic ray muon tomography. Cosmic ray muon tomography, is a promising non-destructive technique that has been recently utilized to monitor or image the contents of dense or well shielded objects, typically not feasible with conventional radiography techniques, e.g., x-ray or neutron. Cosmic ray muon tomography has been used with various levels of success in spent nuclear fuel monitoring, volcano imaging, and cargo container imaging. Further, knowledge of cosmic ray muon momentum spectrum has the potential to significantly improve and expand the use of a variety of recently developed muon-based radiographic techniques. However, existing muon tomography systems rely only on muon tracking and have no momentum measurement capabilities which reduces the image resolution and requires longer measurement times. A fieldable cosmic ray muon spectrometer with momentum measurement capabilities for use in muon tomography is currently missing. In this paper, we will discuss and explore recent advances in cosmic ray muon computed tomography and spectroscopy and their applications to engineering including a new concept for measuring muon momentum using multiple gaseous Cherenkov radiators. By varying the pressure of multiple gas Cherenkov radiators, a set of muon momentum threshold levels can be selected that are triggered only when the incoming muon momentum exceeds that level. As a result, depending on the incoming muon momentum, none to all Cherenkov radiators can be triggered. By analyzing the signals from each radiator, we can estimate the actual muon momentum.","PeriodicalId":262803,"journal":{"name":"HNPS Advances in Nuclear Physics","volume":"118 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125253752","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Major nuclear accidents are rare events causing large and long-lasting medical, environmental, economic, and societal consequences. Urgent mass evacuation and long-term displacement of about 165.000 persons and their long-term resettlement after the 2011 Fukushima-1 accident destabilized Japan. As of March 2020, the official number of displaced persons from their home in Fukushima Prefecture was reduced to 40.335, an action that averted a collective effective dose of about 3,000 man.Sv. Most of the causalities were elderely volunarable pesons, such as patients with chronic diseases, instititionalized individuals, and very poor persons. However, no early radiation-induced somatic effects to public were reported. This article seeks to compare the benefit of the evacuation/resettlement procedure with its cost. The accident-related death toll in Fukushima Prefecture has to be differantiated from that due to the earthquaque and the tsunami that trigered the foressen and prevenatble nuclear 2011 accident. Taking into acount the ratio of the direct and the indirect deaths at the Miyagi and Iwate Prefectures, can be assumed that out the 2.313 indirect life losses in Fukushima registered up at to 2020, only about 165 could be attributed to the eartquake and the tsuami, and few tens due to the radiation induced cancer among the dispaced persons. The mass dispacement resulted in increased incidence of severe somatic effects, mental and psychic disorders, social isolation, insecurity, unemployment, poverty, urbanization, and exploitation. Therefore, the mitigation actions, as designed and implemented, led in a secondary tragedy larger than that due the accident itself, resulting among other things to the death of about 2.100 persons in the name of sparing, in theory, about 150 lives with a latency time of decades
{"title":"Suffering in the Name of Protecting: The Case of the Fukushima Population","authors":"J. Kalef-Ezra","doi":"10.12681/hnps.4795","DOIUrl":"https://doi.org/10.12681/hnps.4795","url":null,"abstract":"Major nuclear accidents are rare events causing large and long-lasting medical, environmental, economic, and societal consequences. Urgent mass evacuation and long-term displacement of about 165.000 persons and their long-term resettlement after the 2011 Fukushima-1 accident destabilized Japan. As of March 2020, the official number of displaced persons from their home in Fukushima Prefecture was reduced to 40.335, an action that averted a collective effective dose of about 3,000 man.Sv. Most of the causalities were elderely volunarable pesons, such as patients with chronic diseases, instititionalized individuals, and very poor persons. However, no early radiation-induced somatic effects to public were reported. This article seeks to compare the benefit of the evacuation/resettlement procedure with its cost. The accident-related death toll in Fukushima Prefecture has to be differantiated from that due to the earthquaque and the tsunami that trigered the foressen and prevenatble nuclear 2011 accident. Taking into acount the ratio of the direct and the indirect deaths at the Miyagi and Iwate Prefectures, can be assumed that out the 2.313 indirect life losses in Fukushima registered up at to 2020, only about 165 could be attributed to the eartquake and the tsuami, and few tens due to the radiation induced cancer among the dispaced persons. The mass dispacement resulted in increased incidence of severe somatic effects, mental and psychic disorders, social isolation, insecurity, unemployment, poverty, urbanization, and exploitation. Therefore, the mitigation actions, as designed and implemented, led in a secondary tragedy larger than that due the accident itself, resulting among other things to the death of about 2.100 persons in the name of sparing, in theory, about 150 lives with a latency time of decades","PeriodicalId":262803,"journal":{"name":"HNPS Advances in Nuclear Physics","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115166636","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Iason Mitsios, F. Pappa, D. Patiris, P. Rouni, M. Anagnostakis, C. Tsabaris
In this work a thorough analysis of the vertical distribution of natural and artificial radionuclides and trace elements in a sediment core sample was conducted. A sediment core of 39 cm length was grabbed from the deep-sea trench (1540 m depth) southern of Samothrace Island, Aegean Sea. The sediment core was then treated at the Hellenic Centre for Marine Research, separated at 1cm increment samples, ranging from 0cm to 39 cm, dried, and milled. A first analysis of the samples was also conducted at HCMR using gamma spectroscopic techniques. Further spectroscopic analysis continued at Nuclear Engineering Department of the National Technical University of Athens (NED-NTUA) using an Extended Range Germanium Detector. The following radionuclides were determined 210Pb, 234Th, 226Ra, 228Ra, 228Th, 137Cs and 40K. Additionally, Instrumental Neutron Activation Analysis was used and the following major and trace elements were identified and quantified: Al, V, La, Sc, Mn, As, Ga, Cr, Zn, Co, Rb, Fe, K, Na and Ce. Based on the analysis of each sample, the vertical distribution of most natural radionuclides showed no significant variation. The vertical distribution of anthropogenic 137Cs was very low and almost constant. Unsupported 210Pb activity was about six times higher than 226Ra, indicating high radon fluxes. Furthermore, neutron activation analysis results indicate that almost all elements are within the expected range based on literature, while K and Na show a slightly increased concentration. For the area, these findings indicate steady and calm sedimentation processes.
{"title":"In Depth Analysis of a Sediment Core from North Aegean Sea","authors":"Iason Mitsios, F. Pappa, D. Patiris, P. Rouni, M. Anagnostakis, C. Tsabaris","doi":"10.12681/hnps.3608","DOIUrl":"https://doi.org/10.12681/hnps.3608","url":null,"abstract":"In this work a thorough analysis of the vertical distribution of natural and artificial radionuclides and trace elements in a sediment core sample was conducted. A sediment core of 39 cm length was grabbed from the deep-sea trench (1540 m depth) southern of Samothrace Island, Aegean Sea. The sediment core was then treated at the Hellenic Centre for Marine Research, separated at 1cm increment samples, ranging from 0cm to 39 cm, dried, and milled. A first analysis of the samples was also conducted at HCMR using gamma spectroscopic techniques. Further spectroscopic analysis continued at Nuclear Engineering Department of the National Technical University of Athens (NED-NTUA) using an Extended Range Germanium Detector. The following radionuclides were determined 210Pb, 234Th, 226Ra, 228Ra, 228Th, 137Cs and 40K. Additionally, Instrumental Neutron Activation Analysis was used and the following major and trace elements were identified and quantified: Al, V, La, Sc, Mn, As, Ga, Cr, Zn, Co, Rb, Fe, K, Na and Ce. Based on the analysis of each sample, the vertical distribution of most natural radionuclides showed no significant variation. The vertical distribution of anthropogenic 137Cs was very low and almost constant. Unsupported 210Pb activity was about six times higher than 226Ra, indicating high radon fluxes. Furthermore, neutron activation analysis results indicate that almost all elements are within the expected range based on literature, while K and Na show a slightly increased concentration. For the area, these findings indicate steady and calm sedimentation processes.","PeriodicalId":262803,"journal":{"name":"HNPS Advances in Nuclear Physics","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127610238","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We have studied shape transition and development of quadrupole deformation in even-even 18-36Ne isotopes by employing covariant density functional theory (CDFT) with density-dependent meson exchange (DD-ME2) and density-dependent point coupling (DD-PC1) parameter sets. A sudden shape transition is observed in the Ne isotopic chain and can be related to the evolution of shell structure of single-particle orbitals. The correlations between shape transition and discontinuity in the other physical observables are also examined. Our results for ground-state properties are in good agreement with the available experimental data and the result of various theoretical models. The present calculations infer the neutron drip line at 34Ne. In addition to shape transition, the bubble structure is also studied for magic nuclei in this chain.
{"title":"A study of shape transition and bubbleness in Ne isotopes","authors":"Pankaj Kumar, V. Thakur, S. K. Dhiman","doi":"10.12681/hnps.3540","DOIUrl":"https://doi.org/10.12681/hnps.3540","url":null,"abstract":"We have studied shape transition and development of quadrupole deformation in even-even 18-36Ne isotopes by employing covariant density functional theory (CDFT) with density-dependent meson exchange (DD-ME2) and density-dependent point coupling (DD-PC1) parameter sets. A sudden shape transition is observed in the Ne isotopic chain and can be related to the evolution of shell structure of single-particle orbitals. The correlations between shape transition and discontinuity in the other physical observables are also examined. Our results for ground-state properties are in good agreement with the available experimental data and the result of various theoretical models. The present calculations infer the neutron drip line at 34Ne. In addition to shape transition, the bubble structure is also studied for magic nuclei in this chain.","PeriodicalId":262803,"journal":{"name":"HNPS Advances in Nuclear Physics","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133945750","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
E. Tsivouraki, S. Chasapoglou, Michalis Serris, M. Axiotis, Georgios Gkatis, S. Harissopulos, M. Kokkoris, A. Lagoyannis, Stavros Patas, R. Vlastou
Neutron nuclear reactions can provide significant information in the field of nuclear physics and applications. Hafnium (Hf) is one of the rare-earth isotopes with a relative large neutron total cross-section in the thermal neutron energy region and neutron induced reactions in reactor materials could lead to the production of long-lived isomeric states of Hf isotopes. Thus, the knowledge of neutron cross-sections on Hf isotopes is of great importance for basic research in Nuclear Physics as well as for applications concerning the interaction of neutrons with matter. In this study measurements of experimental cross section for the 176Hf(n,2n)175Hf and 180Hf(n,n΄γ)180mHf reactions were carried out, using the activation technique. The neutron beam energy at 18.9 MeV was produced via the 3H(d,n)4He reaction at the 5.5 MeV Tandem Van de Graaf accelerator laboratory of NCSR “Demokritos”. A thin metallic foil of natural Hf was used, while for the determination of the neutron flux at the target position a reference foil of Al was placed at the back of the Hf target. The irradiation was continuous for 28 hours leading to a total neutron fluence of 1010 n/cm2 and a BF3 detector was used for monitoring the neutron flux during the irradiation. After the end of irradiation, the activity of the Hf target and the Al foil were measured off-line by two HPGe detectors. Both detector efficiencies were obtained using a calibrated 152Eu source, placed in the same distance as the target and the reference foil. The 176Hf(n,2n)175Hf reaction has been corrected from the contribution of 177Hf(n,3n)175Hf and the 174Hf(n,γ)175Hf reactions and the 180Hf(n,n΄γ)180mHf reaction from the 179Hf(n,γ)180mHf. Theoretical calculations of the 174Hf(n,2n)175Hf, 176Hf(n,2n)175Hf and 180Hf(n,n΄γ)180mHf reaction cross-sections have also been performed using the nuclear statistical code “EMPIRE 3.2.3” and they have been compared with the data.
中子核反应在核物理和应用领域提供了重要的信息。铪(Hf)是热中子能区中子总截面较大的稀土同位素之一，反应堆材料中的中子诱导反应可产生Hf同位素的长寿命同分异构体态。因此，了解Hf同位素的中子截面对核物理学的基础研究以及中子与物质相互作用的应用具有重要意义。本研究采用活化技术测量了176Hf(n,2n)175Hf和180Hf(n,n΄γ)180mHf反应的实验截面。在NCSR“Demokritos”5.5 MeV串联Van de Graaf加速器实验室，通过3H(d,n)4He反应产生了18.9 MeV的中子束能量。使用天然Hf的薄金属箔，而在Hf靶的背面放置Al的参考箔来测定靶位置的中子通量。辐照持续28小时，总中子通量为1010 n/cm2，辐照过程中使用BF3探测器监测中子通量。辐照结束后，用两台HPGe探测器离线测量Hf靶和Al箔的活度。两个探测器的效率都是使用校准的152Eu源获得的，该源与目标和参考箔放置在相同的距离。由177Hf(n,3n)175Hf和174Hf(n，γ)175Hf的贡献修正了176Hf(n,2n)175Hf反应，由179Hf(n，γ)180mHf修正了180Hf(n,n΄γ)180mHf反应。用核统计程序“EMPIRE 3.2.3”对174Hf(n,2n)175Hf、176Hf(n,2n)175Hf和180Hf(n,n΄γ)180mHf反应截面进行了理论计算，并与实验数据进行了比较。
{"title":"Study of the 176Hf(n,2n)175Hf cross section at 18.9 MeV","authors":"E. Tsivouraki, S. Chasapoglou, Michalis Serris, M. Axiotis, Georgios Gkatis, S. Harissopulos, M. Kokkoris, A. Lagoyannis, Stavros Patas, R. Vlastou","doi":"10.12681/hnps.3710","DOIUrl":"https://doi.org/10.12681/hnps.3710","url":null,"abstract":"Neutron nuclear reactions can provide significant information in the field of nuclear physics and applications. Hafnium (Hf) is one of the rare-earth isotopes with a relative large neutron total cross-section in the thermal neutron energy region and neutron induced reactions in reactor materials could lead to the production of long-lived isomeric states of Hf isotopes. Thus, the knowledge of neutron cross-sections on Hf isotopes is of great importance for basic research in Nuclear Physics as well as for applications concerning the interaction of neutrons with matter. In this study measurements of experimental cross section for the 176Hf(n,2n)175Hf and 180Hf(n,n΄γ)180mHf reactions were carried out, using the activation technique. The neutron beam energy at 18.9 MeV was produced via the 3H(d,n)4He reaction at the 5.5 MeV Tandem Van de Graaf accelerator laboratory of NCSR “Demokritos”. A thin metallic foil of natural Hf was used, while for the determination of the neutron flux at the target position a reference foil of Al was placed at the back of the Hf target. The irradiation was continuous for 28 hours leading to a total neutron fluence of 1010 n/cm2 and a BF3 detector was used for monitoring the neutron flux during the irradiation. After the end of irradiation, the activity of the Hf target and the Al foil were measured off-line by two HPGe detectors. Both detector efficiencies were obtained using a calibrated 152Eu source, placed in the same distance as the target and the reference foil. The 176Hf(n,2n)175Hf reaction has been corrected from the contribution of 177Hf(n,3n)175Hf and the 174Hf(n,γ)175Hf reactions and the 180Hf(n,n΄γ)180mHf reaction from the 179Hf(n,γ)180mHf. Theoretical calculations of the 174Hf(n,2n)175Hf, 176Hf(n,2n)175Hf and 180Hf(n,n΄γ)180mHf reaction cross-sections have also been performed using the nuclear statistical code “EMPIRE 3.2.3” and they have been compared with the data.","PeriodicalId":262803,"journal":{"name":"HNPS Advances in Nuclear Physics","volume":"251 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123326298","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Stamati, N. Patronis, M. Bacak, S. Amaducci, Adrià Casanovas Hoste, Francisco Garcia Infantes, A. Manna, A. Mengoni, Jose Antonio Pavon Rodriguez, Antonio Javier Praena Rodriguez, M. Spelta
After CERN’s Long Shutdown 2, the n_TOF facility infrastructure was largely upgraded. The biggest change is the installation of a new lead spallation target, the performance of which needs to be carefully examined. During Summer 2021, the facility’s two flight paths were characterised in terms of neutron beam energy distribution, profile and resolution. In this work, the characterisation of the facility is described and the first results are given.
{"title":"Preparing Phase 4 of the n_TOF/CERN facility","authors":"M. Stamati, N. Patronis, M. Bacak, S. Amaducci, Adrià Casanovas Hoste, Francisco Garcia Infantes, A. Manna, A. Mengoni, Jose Antonio Pavon Rodriguez, Antonio Javier Praena Rodriguez, M. Spelta","doi":"10.12681/hnps.3610","DOIUrl":"https://doi.org/10.12681/hnps.3610","url":null,"abstract":"After CERN’s Long Shutdown 2, the n_TOF facility infrastructure was largely upgraded. The biggest change is the installation of a new lead spallation target, the performance of which needs to be carefully examined. During Summer 2021, the facility’s two flight paths were characterised in terms of neutron beam energy distribution, profile and resolution. In this work, the characterisation of the facility is described and the first results are given.","PeriodicalId":262803,"journal":{"name":"HNPS Advances in Nuclear Physics","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123527309","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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