Pub Date : 2020-11-20DOI: 10.1142/s0218301320500925
A. Yasser, T. A. Nahool, M. Anwar, C. Bowerman, G. A. Yahya
In this paper, we investigate the benefits of machine learning (ML) approaches in predicting the spectra of meson bound states. A linear model (LM) approach is used to predict the spectra of some heavy mesons. Our proposed method has been successfully reproduced in recent experiments, to validate known outcomes. Our results are compared favorably to those obtained using other techniques. This novel perspective opens up a new future in the use of ML in the field of particle physics.
{"title":"A new machine learning approach for predicting the spectra of meson bound states","authors":"A. Yasser, T. A. Nahool, M. Anwar, C. Bowerman, G. A. Yahya","doi":"10.1142/s0218301320500925","DOIUrl":"https://doi.org/10.1142/s0218301320500925","url":null,"abstract":"In this paper, we investigate the benefits of machine learning (ML) approaches in predicting the spectra of meson bound states. A linear model (LM) approach is used to predict the spectra of some heavy mesons. Our proposed method has been successfully reproduced in recent experiments, to validate known outcomes. Our results are compared favorably to those obtained using other techniques. This novel perspective opens up a new future in the use of ML in the field of particle physics.","PeriodicalId":14032,"journal":{"name":"International Journal of Modern Physics E-nuclear Physics","volume":"8 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84166169","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}
Pub Date : 2020-11-18DOI: 10.1142/s0218301320500846
Nabeel F. Lattoofi, A. Alzubadi
The partial photonuclear [Formula: see text], pn) and [Formula: see text] and the total photonuclear cross-sections (the giant dipole resonance (GDR)) have been investigated theoretically for neodymium isotopes, namely [Formula: see text]Nd, using framework of the EMPIRE 3.2.2 code. The energy, width and cross-section parameters of the GDR used in our calculations have been investigated in this paper depending on the deformation parameters of nuclei. The calculated results have been compared with the experimental data and with those calculated using Lorentzian fitting parameters. Our calculations show a good agreement for all isotopes under study and give better results than the results calculated with Lorentzian parameters. Furthermore, the neutron number dependence of the total and partial photonuclear cross-sections has also been discussed. The results appear that the EMPIRE code used is a perfect tool for reproducing the splitting in the GDR for deformed [Formula: see text]Nd isotope in two distinct dipole modes which are perfectly consistent with the experimental results. It has also been shown that the present parameters are suitable parameters for reproducing the GDR for spherical, or nearly spherical, and the deformed ([Formula: see text]Nd) neodymium isotopes. The parameters have been indicating the small deformation in [Formula: see text]Nd, which cannot be shown by the Lorentzian fitting parameters.
{"title":"Study of giant dipole resonances for neodymium isotopes with an exciton model","authors":"Nabeel F. Lattoofi, A. Alzubadi","doi":"10.1142/s0218301320500846","DOIUrl":"https://doi.org/10.1142/s0218301320500846","url":null,"abstract":"The partial photonuclear [Formula: see text], pn) and [Formula: see text] and the total photonuclear cross-sections (the giant dipole resonance (GDR)) have been investigated theoretically for neodymium isotopes, namely [Formula: see text]Nd, using framework of the EMPIRE 3.2.2 code. The energy, width and cross-section parameters of the GDR used in our calculations have been investigated in this paper depending on the deformation parameters of nuclei. The calculated results have been compared with the experimental data and with those calculated using Lorentzian fitting parameters. Our calculations show a good agreement for all isotopes under study and give better results than the results calculated with Lorentzian parameters. Furthermore, the neutron number dependence of the total and partial photonuclear cross-sections has also been discussed. The results appear that the EMPIRE code used is a perfect tool for reproducing the splitting in the GDR for deformed [Formula: see text]Nd isotope in two distinct dipole modes which are perfectly consistent with the experimental results. It has also been shown that the present parameters are suitable parameters for reproducing the GDR for spherical, or nearly spherical, and the deformed ([Formula: see text]Nd) neodymium isotopes. The parameters have been indicating the small deformation in [Formula: see text]Nd, which cannot be shown by the Lorentzian fitting parameters.","PeriodicalId":14032,"journal":{"name":"International Journal of Modern Physics E-nuclear Physics","volume":"8 1","pages":"2050084"},"PeriodicalIF":0.0,"publicationDate":"2020-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74754455","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}
Pub Date : 2020-11-18DOI: 10.1142/s0218301320500858
N. N. Le, N. N. Duy
This study reports the [Formula: see text]-decay half-lives of 39 transfermium isotopes with [Formula: see text], most of which have not been observed. The half-lives were calculated using micro–macroscopic approaches and semi-empirical formulae, applying current [Formula: see text]-decay Q-values from the latest mass database, AME2016. These results were compared to predicted values in previous works to evaluate the efficiency of and difference between various calculation methods. We found that the [Formula: see text]-resonance approach used in a previous study is not appropriate to predict though most other approaches are mutually consistent. An uncertainty of 70% was observed in the present theoretical calculations, similar to that observed in measurements. A Q-value uncertainty of 10% can lead to a large variation of 3 orders of magnitude in predicted [Formula: see text]-decay half-life. We also found that the dominance of either [Formula: see text] decay or spontaneous fission is unclear for the isotopes with [Formula: see text]–[Formula: see text], whereas most of the nuclei of [Formula: see text]–[Formula: see text] can be clearly identified as [Formula: see text] emitters. Finally, we provide the updated [Formula: see text]-decay half-lives for the isotopes of interest, including their uncertainties and corresponding decay modes.
{"title":"Examination of α-decay half-lives of undetected transfermium isotopes","authors":"N. N. Le, N. N. Duy","doi":"10.1142/s0218301320500858","DOIUrl":"https://doi.org/10.1142/s0218301320500858","url":null,"abstract":"This study reports the [Formula: see text]-decay half-lives of 39 transfermium isotopes with [Formula: see text], most of which have not been observed. The half-lives were calculated using micro–macroscopic approaches and semi-empirical formulae, applying current [Formula: see text]-decay Q-values from the latest mass database, AME2016. These results were compared to predicted values in previous works to evaluate the efficiency of and difference between various calculation methods. We found that the [Formula: see text]-resonance approach used in a previous study is not appropriate to predict though most other approaches are mutually consistent. An uncertainty of 70% was observed in the present theoretical calculations, similar to that observed in measurements. A Q-value uncertainty of 10% can lead to a large variation of 3 orders of magnitude in predicted [Formula: see text]-decay half-life. We also found that the dominance of either [Formula: see text] decay or spontaneous fission is unclear for the isotopes with [Formula: see text]–[Formula: see text], whereas most of the nuclei of [Formula: see text]–[Formula: see text] can be clearly identified as [Formula: see text] emitters. Finally, we provide the updated [Formula: see text]-decay half-lives for the isotopes of interest, including their uncertainties and corresponding decay modes.","PeriodicalId":14032,"journal":{"name":"International Journal of Modern Physics E-nuclear Physics","volume":"546 1","pages":"2050085"},"PeriodicalIF":0.0,"publicationDate":"2020-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85661498","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}
Pub Date : 2020-11-09DOI: 10.1142/s0218301320500901
A. Allami, A. Alzubadi
The nuclear shell model with the Skyrme–Hartree–Fock (SHF), as a nonrelativistic approach, and the Relativistic Hartree–Fock–Bogoliubov (RHFB) methods have been used to study the nuclear structure of some exotic nuclei at the proton and neutron drip lines. Different Skyrme parametrizations, in particular SkM*, SkX, SkO, SLy4, Skxs25 and Z, have been used in the nonrelativistic region. In the relativistic region, the density-dependence meson-exchange models and density-dependence point-coupling models are used. Both methods are used to study ground state properties such as binding energy, mass radial density distribution and the corresponding root mean square (rms) mass radii. The fragmentation reaction cross-section is used as an important property to investigate the halo structure. Strong evidence for existence of a neutron halo in [Formula: see text]Li and [Formula: see text]Be and proton halo in [Formula: see text]Ne, [Formula: see text]Al and [Formula: see text]P are found using the SHF model and reaction cross-section. The ability of the SHF model to study the exotic structure with shell model occupation probability is confirmed.
{"title":"Study of the nuclear structure of some exotic nuclei using nonrelativistic and relativistic mean-field methods","authors":"A. Allami, A. Alzubadi","doi":"10.1142/s0218301320500901","DOIUrl":"https://doi.org/10.1142/s0218301320500901","url":null,"abstract":"The nuclear shell model with the Skyrme–Hartree–Fock (SHF), as a nonrelativistic approach, and the Relativistic Hartree–Fock–Bogoliubov (RHFB) methods have been used to study the nuclear structure of some exotic nuclei at the proton and neutron drip lines. Different Skyrme parametrizations, in particular SkM*, SkX, SkO, SLy4, Skxs25 and Z, have been used in the nonrelativistic region. In the relativistic region, the density-dependence meson-exchange models and density-dependence point-coupling models are used. Both methods are used to study ground state properties such as binding energy, mass radial density distribution and the corresponding root mean square (rms) mass radii. The fragmentation reaction cross-section is used as an important property to investigate the halo structure. Strong evidence for existence of a neutron halo in [Formula: see text]Li and [Formula: see text]Be and proton halo in [Formula: see text]Ne, [Formula: see text]Al and [Formula: see text]P are found using the SHF model and reaction cross-section. The ability of the SHF model to study the exotic structure with shell model occupation probability is confirmed.","PeriodicalId":14032,"journal":{"name":"International Journal of Modern Physics E-nuclear Physics","volume":"27 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76332780","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}
Pub Date : 2020-11-02DOI: 10.1142/S0218301320500792
O. Artun
The charge, proton and neutron density distributions along with nuclear properties were calculated by Hartree–Fock approach with Skyrme force interaction for isotopic Pb chain (88 ≤ N ≤ 184). The e...
{"title":"Nuclear structure properties in neutron stars","authors":"O. Artun","doi":"10.1142/S0218301320500792","DOIUrl":"https://doi.org/10.1142/S0218301320500792","url":null,"abstract":"The charge, proton and neutron density distributions along with nuclear properties were calculated by Hartree–Fock approach with Skyrme force interaction for isotopic Pb chain (88 ≤ N ≤ 184). The e...","PeriodicalId":14032,"journal":{"name":"International Journal of Modern Physics E-nuclear Physics","volume":"214 1","pages":"2050079"},"PeriodicalIF":0.0,"publicationDate":"2020-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84682889","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}
Pub Date : 2020-11-01DOI: 10.1142/s0218301320400078
D. Tlustý
The exploration of the Quantum Chromodynamics (QCD) phase diagram has been one of the main drivers of contemporary nuclear physics. Heavy-ion collisions provide a powerful tool to explore phase structures of strongly interacting hot and dense nuclear matter called Quark–Gluon Plasma (QGP). The Relativistic Heavy Ion Collider (RHIC) is uniquely suited to map the QCD phase diagram by varying the energy of collisions, as well as nuclei species. These proceedings discuss the most recent results from the STAR experiment at RHIC and future plans.
{"title":"STAR Heavy-ion results","authors":"D. Tlustý","doi":"10.1142/s0218301320400078","DOIUrl":"https://doi.org/10.1142/s0218301320400078","url":null,"abstract":"The exploration of the Quantum Chromodynamics (QCD) phase diagram has been one of the main drivers of contemporary nuclear physics. Heavy-ion collisions provide a powerful tool to explore phase structures of strongly interacting hot and dense nuclear matter called Quark–Gluon Plasma (QGP). The Relativistic Heavy Ion Collider (RHIC) is uniquely suited to map the QCD phase diagram by varying the energy of collisions, as well as nuclei species. These proceedings discuss the most recent results from the STAR experiment at RHIC and future plans.","PeriodicalId":14032,"journal":{"name":"International Journal of Modern Physics E-nuclear Physics","volume":"12 1","pages":"2040007"},"PeriodicalIF":0.0,"publicationDate":"2020-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72914968","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}
Pub Date : 2020-11-01DOI: 10.1142/s0218301320400030
I. Artem
Heavy-flavor quarks are considered to be effective probes of the Quark–Gluon Plasma (QGP) produced in ultra-relativistic heavy-ion collisions. Since quarks have a large mass, their production takes place mostly in initial hard processes, and it is calculable using perturbative QCD. Thus, heavy flavor quarks can be considered as ideal early-generated penetrating probes of the created medium and utilized to investigate mass-dependent properties of in-medium parton energy loss. Moreover, the measurement of heavy-flavor jet production in pp, besides being a natural reference for Pb–Pb studies, allows testing pQCD calculations and models of charm fragmentation in vacuum. In addition, similar measurements in p–Pb collisions allow assessing the importance of cold nuclear matter effects. The ALICE experiment at the LHC has excellent particle tracking capabilities, that allow for a precise jet reconstruction and for the identification of [Formula: see text]-meson and beauty hadron decay vertices, displaced hundreds of micrometers from the primary interaction vertex. In this proceedings, we will report the latest heavy-flavor jet measurements performed in p–Pb and pp collisions.
{"title":"Heavy flavor jets in ALICE","authors":"I. Artem","doi":"10.1142/s0218301320400030","DOIUrl":"https://doi.org/10.1142/s0218301320400030","url":null,"abstract":"Heavy-flavor quarks are considered to be effective probes of the Quark–Gluon Plasma (QGP) produced in ultra-relativistic heavy-ion collisions. Since quarks have a large mass, their production takes place mostly in initial hard processes, and it is calculable using perturbative QCD. Thus, heavy flavor quarks can be considered as ideal early-generated penetrating probes of the created medium and utilized to investigate mass-dependent properties of in-medium parton energy loss. Moreover, the measurement of heavy-flavor jet production in pp, besides being a natural reference for Pb–Pb studies, allows testing pQCD calculations and models of charm fragmentation in vacuum. In addition, similar measurements in p–Pb collisions allow assessing the importance of cold nuclear matter effects. The ALICE experiment at the LHC has excellent particle tracking capabilities, that allow for a precise jet reconstruction and for the identification of [Formula: see text]-meson and beauty hadron decay vertices, displaced hundreds of micrometers from the primary interaction vertex. In this proceedings, we will report the latest heavy-flavor jet measurements performed in p–Pb and pp collisions.","PeriodicalId":14032,"journal":{"name":"International Journal of Modern Physics E-nuclear Physics","volume":"1 1","pages":"2040003"},"PeriodicalIF":0.0,"publicationDate":"2020-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89602473","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}
Pub Date : 2020-10-28DOI: 10.1142/s0218301320500731
S. Åberg, Akhilesh Yadav, A. Shukla
Experimental observation of 34Si as a proton bubble nuclei has heated up the interest in the study of exotic bubble shaped nuclei. In this work, some of the potential doubly bubble-like (for proton as well as neutron both simultaneously) cases have been explored using relativistic Hartree–Bogoliubov (RHB) in light mass region, specially around N or Z = 14. Further, the role of pairing and the evolution of new shell gaps around N or Z = 32 and 34 have been investigated, as one moves toward drip lines. This study suggests that the occupancies/vacancies of neutron/proton orbitals for lower angular momentum state plays major role in nuclear structure to create bubble-like structure and 822O14, 1220Mg8 and 1448Si34 may have dual bubble-like structures.
{"title":"Possible dual bubble-like structure predicted by the relativistic Hartree–Bogoliubov model","authors":"S. Åberg, Akhilesh Yadav, A. Shukla","doi":"10.1142/s0218301320500731","DOIUrl":"https://doi.org/10.1142/s0218301320500731","url":null,"abstract":"Experimental observation of 34Si as a proton bubble nuclei has heated up the interest in the study of exotic bubble shaped nuclei. In this work, some of the potential doubly bubble-like (for proton as well as neutron both simultaneously) cases have been explored using relativistic Hartree–Bogoliubov (RHB) in light mass region, specially around N or Z = 14. Further, the role of pairing and the evolution of new shell gaps around N or Z = 32 and 34 have been investigated, as one moves toward drip lines. This study suggests that the occupancies/vacancies of neutron/proton orbitals for lower angular momentum state plays major role in nuclear structure to create bubble-like structure and 822O14, 1220Mg8 and 1448Si34 may have dual bubble-like structures.","PeriodicalId":14032,"journal":{"name":"International Journal of Modern Physics E-nuclear Physics","volume":"76 1","pages":"2050073"},"PeriodicalIF":0.0,"publicationDate":"2020-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73205194","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}
Pub Date : 2020-10-22DOI: 10.1142/s0218301320500706
S. Nejati, O. N. Ghodsi
In this study, the effect of the surface symmetry energy on the neutron skin thickness and division of it into the bulk and surface parts are investigated by determination of the symmetry energy co...
{"title":"Study of the dependence of alpha decay half-life on the surface symmetry energy","authors":"S. Nejati, O. N. Ghodsi","doi":"10.1142/s0218301320500706","DOIUrl":"https://doi.org/10.1142/s0218301320500706","url":null,"abstract":"In this study, the effect of the surface symmetry energy on the neutron skin thickness and division of it into the bulk and surface parts are investigated by determination of the symmetry energy co...","PeriodicalId":14032,"journal":{"name":"International Journal of Modern Physics E-nuclear Physics","volume":"29 1","pages":"2050070"},"PeriodicalIF":0.0,"publicationDate":"2020-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74641744","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}
Pub Date : 2020-10-10DOI: 10.1142/s021830132050069x
K. Jha, Pawan Kumar, S. Sarkar, P. K. Raina
In many shell model interactions, the tensor force monopole matrix elements often retain systematic trends originating in the bare tensor force. However, in this work, we find that Isospin T = 0 te...
{"title":"Modification of tensor force in 0p-shell model effective interaction","authors":"K. Jha, Pawan Kumar, S. Sarkar, P. K. Raina","doi":"10.1142/s021830132050069x","DOIUrl":"https://doi.org/10.1142/s021830132050069x","url":null,"abstract":"In many shell model interactions, the tensor force monopole matrix elements often retain systematic trends originating in the bare tensor force. However, in this work, we find that Isospin T = 0 te...","PeriodicalId":14032,"journal":{"name":"International Journal of Modern Physics E-nuclear Physics","volume":"23 1","pages":"2050069"},"PeriodicalIF":0.0,"publicationDate":"2020-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73849312","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}