Thermal neutron flux (Фth) of Americium-Beryllium (Am-Be) neutron source has been measured by adopting the foil activation method. The neutrons emitted from Am-Be source are used to activate the indium-115 (115In) foil. The gamma radiations emitted from the activated isomer 116m1In are measured with NaI(Tl) and HPGe detectors. The thermal neutron flux is measured by adopting the cadmium (Cd) foil difference technique in which the Cd foil placed in front of the source to prevent the thermal neutrons from entering into the indium foil. The neutron flux is determined by measuring the gamma radiation emitted from indium foil using a low and high energy resolution NaI(Tl) and HPGe detectors respectively. The measured thermal neutron flux obtained from both detectors has been compared and found that the Фth does not depend on the resolution and type of the detectors used in the present investigations.
{"title":"Determination of the Thermal Neutron Flux by Measuring Gamma Radiations with High and Low Resolution Detectors","authors":"M. Hosamani, A. S. Bennal, N. M. Badiger","doi":"10.15415/jnp.2019.62027","DOIUrl":"https://doi.org/10.15415/jnp.2019.62027","url":null,"abstract":"Thermal neutron flux (Фth) of Americium-Beryllium (Am-Be) neutron source has been measured by adopting the foil activation method. The neutrons emitted from Am-Be source are used to activate the indium-115 (115In) foil. The gamma radiations emitted from the activated isomer 116m1In are measured with NaI(Tl) and HPGe detectors. The thermal neutron flux is measured by adopting the cadmium (Cd) foil difference technique in which the Cd foil placed in front of the source to prevent the thermal neutrons from entering into the indium foil. The neutron flux is determined by measuring the gamma radiation emitted from indium foil using a low and high energy resolution NaI(Tl) and HPGe detectors respectively. The measured thermal neutron flux obtained from both detectors has been compared and found that the Фth does not depend on the resolution and type of the detectors used in the present investigations.","PeriodicalId":16534,"journal":{"name":"Journal of Nuclear Physics, Material Sciences, Radiation and Applications","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83079896","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 : 2019-02-26DOI: 10.15415/jnp.2019.6.02.0134-141
B. Maheshwari
{"title":"Goodness of Generalized Seniority in Even-even Sn Isotopes","authors":"B. Maheshwari","doi":"10.15415/jnp.2019.6.02.0134-141","DOIUrl":"https://doi.org/10.15415/jnp.2019.6.02.0134-141","url":null,"abstract":"","PeriodicalId":16534,"journal":{"name":"Journal of Nuclear Physics, Material Sciences, Radiation and Applications","volume":"24 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75043506","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}
Seniority has proved to be a unique and simple probe to address some of the complex issues underlying nuclear structure of nuclei close to magic numbers. An extension from the concept of seniority in single-j shell to generalized seniority in multi-j shell has recently been provided by us. We have, consequently, established new selection rules for gamma decays and discovered the new seniority isomers decaying via odd electric multipole operators. We have successfully explained the B(EL; L=1,2,3) behavior of various high spin isomers and other excited states. More specifically, we have been able to explain the long-standing puzzle of double hump in the B(E2) values for the first excited 2+ states of even-even Z=50 (Sn) isotopes. In the present paper, we review these generalized seniority calculations with emphasis on even-even Sn isotopes. We first discuss the generalized seniority results for the E1 decaying 13- isomers and E2 decaying 10+, 15- isomers, and then present the cases of first-excited 2+ and 3- states. The generalized seniority proves out to be a reasonably good quantum number. The significance of configuration mixing is found to be true. The calculated results has been validated till high seniority v=4 states and expected to be valid for higher seniority v=6,… states also.
{"title":"Goodness of Generalized Seniority in Even-even Sn Isotopes.","authors":"B. Maheshwari","doi":"10.15415/JNP.2019.62023","DOIUrl":"https://doi.org/10.15415/JNP.2019.62023","url":null,"abstract":"Seniority has proved to be a unique and simple probe to address some of the complex issues underlying nuclear structure of nuclei close to magic numbers. An extension from the concept of seniority in single-j shell to generalized seniority in multi-j shell has recently been provided by us. We have, consequently, established new selection rules for gamma decays and discovered the new seniority isomers decaying via odd electric multipole operators. We have successfully explained the B(EL; L=1,2,3) behavior of various high spin isomers and other excited states. More specifically, we have been able to explain the long-standing puzzle of double hump in the B(E2) values for the first excited 2+ states of even-even Z=50 (Sn) isotopes. In the present paper, we review these generalized seniority calculations with emphasis on even-even Sn isotopes. We first discuss the generalized seniority results for the E1 decaying 13- isomers and E2 decaying 10+, 15- isomers, and then present the cases of first-excited 2+ and 3- states. The generalized seniority proves out to be a reasonably good quantum number. The significance of configuration mixing is found to be true. The calculated results has been validated till high seniority v=4 states and expected to be valid for higher seniority v=6,… states also. \u0000 ","PeriodicalId":16534,"journal":{"name":"Journal of Nuclear Physics, Material Sciences, Radiation and Applications","volume":"15 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80369704","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}
H. Vega-Carrillo, V.P. Singh, C. R. Escobedo-Galván, Diego Medina Castro, Arturo Agustin Ortiz Hernandez, Teodoro Rivera-Montalvo, Segundo Agustín Martínez-Ovalle
A mini subcritical nuclear reactor was designed using Monte Carlo methods. The reactor has light water as moderator, natural uranium as fuel, and a 239PuBe neutron source. In the design uranium fuel was modeled in an arrangement of concentric rings: 8.5, 14.5, 20.5 26.5, 32.5 cm-inner radius, 3 cm-thick, and 36 cm-high. Different models were made from a single ring of natural uranium to five rings. For each case, the neutron spectra, the neutron fluence distribution, the effective multiplication factor, the amplification factor, and the reactor power were estimated. The ambient dose equivalent rate outside the mini reactor was also estimated. The maximum value for the keff (0.78) was obtained when five rings of fuel were used; this value is close to 0.86 which belongs to a Nuclear Chicago subcritical reactor which requires almost twice the amount of uranium than the mini subcritical reactor.
{"title":"Mini Subcritical Nuclear Reactor","authors":"H. Vega-Carrillo, V.P. Singh, C. R. Escobedo-Galván, Diego Medina Castro, Arturo Agustin Ortiz Hernandez, Teodoro Rivera-Montalvo, Segundo Agustín Martínez-Ovalle","doi":"10.15415/JNP.2019.62026","DOIUrl":"https://doi.org/10.15415/JNP.2019.62026","url":null,"abstract":"A mini subcritical nuclear reactor was designed using Monte Carlo methods. The reactor has light water as moderator, natural uranium as fuel, and a 239PuBe neutron source. In the design uranium fuel was modeled in an arrangement of concentric rings: 8.5, 14.5, 20.5 26.5, 32.5 cm-inner radius, 3 cm-thick, and 36 cm-high. Different models were made from a single ring of natural uranium to five rings. For each case, the neutron spectra, the neutron fluence distribution, the effective multiplication factor, the amplification factor, and the reactor power were estimated. The ambient dose equivalent rate outside the mini reactor was also estimated. The maximum value for the keff (0.78) was obtained when five rings of fuel were used; this value is close to 0.86 which belongs to a Nuclear Chicago subcritical reactor which requires almost twice the amount of uranium than the mini subcritical reactor.","PeriodicalId":16534,"journal":{"name":"Journal of Nuclear Physics, Material Sciences, Radiation and Applications","volume":"42 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82283021","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}
With reference to our earlier published views on large nuclear gravitational constant Gs, nuclear elementary charge es and strong coupling constant αs ≅ e/es 2, in this paper, we present simple relations for nuclear stability range, binding energy of isotopes and magic proton numbers. Even though ‘speculative’ in nature, proposed concepts are simple to understand, easy to implement, result oriented, effective and unified. Our proposed model seems to span across the Planck scale and nuclear scale and can be called as SPAN model (STRANGE* physics of atomic nucleus)
{"title":"On the Role of Large Nuclear Gravity in Understanding Strong Coupling Constant, Nuclear Stability Range, Binding Energy of Isotopes and Magic proton numbers – A Critical Review","authors":"U.V.S. Seshavatharam, S. Lakshminarayana","doi":"10.15415/jnp.2019.62024","DOIUrl":"https://doi.org/10.15415/jnp.2019.62024","url":null,"abstract":"With reference to our earlier published views on large nuclear gravitational constant Gs, nuclear elementary charge es and strong coupling constant αs ≅ e/es 2, in this paper, we present simple relations for nuclear stability range, binding energy of isotopes and magic proton numbers. Even though ‘speculative’ in nature, proposed concepts are simple to understand, easy to implement, result oriented, effective and unified. Our proposed model seems to span across the Planck scale and nuclear scale and can be called as SPAN model (STRANGE* physics of atomic nucleus)","PeriodicalId":16534,"journal":{"name":"Journal of Nuclear Physics, Material Sciences, Radiation and Applications","volume":"36 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76688933","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 : 2018-10-03DOI: 10.20944/PREPRINTS201810.0053.V1
U. Seshavatharam, S. Lakshminarayana
With reference to our earlier published views on large nuclear gravitational constant , nuclear elementary charge and strong coupling constant , in this paper, we present simple relations for nuclear stability range, binding energy of isotopes and magic proton numbers.
{"title":"On the Role of Large Nuclear Gravity in Understanding Strong Coupling Constant, Nuclear Stability Range, Binding Energy of Isotopes and Magic proton numbers – A Critical Review","authors":"U. Seshavatharam, S. Lakshminarayana","doi":"10.20944/PREPRINTS201810.0053.V1","DOIUrl":"https://doi.org/10.20944/PREPRINTS201810.0053.V1","url":null,"abstract":"With reference to our earlier published views on large nuclear gravitational constant , nuclear elementary charge and strong coupling constant , in this paper, we present simple relations for nuclear stability range, binding energy of isotopes and magic proton numbers.","PeriodicalId":16534,"journal":{"name":"Journal of Nuclear Physics, Material Sciences, Radiation and Applications","volume":"30 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77544267","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. A. Fuentes, L. Mandujano, R. López, L. Guarneros, E. Azorín, D. Osorio-González, Molecular Biophysical Modeling
The prostate-specific membrane antigen (PSMA) is a 100 kDa type II transmembrane glycoprotein with enzymatic activity similar to the family of zinc-dependent exopeptidases. This protein is of great medical and pharmacological interest as overexpression in prostate cells is related to the progression of prostate cancer; therefore, it represents an important target for the design of radiopharmaceuticals. The presence of two Zn2+ ions in the active site is crucial to the enzymatic activity and the design of high-affinity inhibitors. The amino acid residues coordinating these ions are highly conserved in PSMA orthologs from plants to mammals, and site-mutagenesis assays of these residues show a loss of enzymatic function or reduction of the kinetic parameters. In the present work, we performed molecular dynamics simulation of PSMA with the purpose of characterizing it energetically and structurally. We elucidated the differences of PSMA with its two Zn+2 ions as cofactors and without them in the free energy profile, and in four structural parameters: root mean square deviations and root mean square fluctuations by atom and amino acid residue, radius of gyration, and solvent accessible surface area.
{"title":"In silico Analysis of the Structural Properties of PSMA and its Energetic Relationship with Zn as Cofactor","authors":"M. A. Fuentes, L. Mandujano, R. López, L. Guarneros, E. Azorín, D. Osorio-González, Molecular Biophysical Modeling","doi":"10.15415/JNP.2018.61020","DOIUrl":"https://doi.org/10.15415/JNP.2018.61020","url":null,"abstract":"The prostate-specific membrane antigen (PSMA) is a 100 kDa type II transmembrane glycoprotein with enzymatic activity similar to the family of zinc-dependent exopeptidases. This protein is of great medical and pharmacological interest as overexpression in prostate cells is related to the progression of prostate cancer; therefore, it represents an important target for the design of radiopharmaceuticals. The presence of two Zn2+ ions in the active site is crucial to the enzymatic activity and the design of high-affinity inhibitors. The amino acid residues coordinating these ions are highly conserved in PSMA orthologs from plants to mammals, and site-mutagenesis assays of these residues show a loss of enzymatic function or reduction of the kinetic parameters. In the present work, we performed molecular dynamics simulation of PSMA with the purpose of characterizing it energetically and structurally. We elucidated the differences of PSMA with its two Zn+2 ions as cofactors and without them in the free energy profile, and in four structural parameters: root mean square deviations and root mean square fluctuations by atom and amino acid residue, radius of gyration, and solvent accessible surface area.","PeriodicalId":16534,"journal":{"name":"Journal of Nuclear Physics, Material Sciences, Radiation and Applications","volume":"88 1","pages":"115-120"},"PeriodicalIF":0.0,"publicationDate":"2018-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73632824","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}
B. Leal-Acevedo, P. G. Reyes-Romero, Fermín Castillo, I. Gamboa-deBuen
The specific and linear energy was calculated in target sizes of 10 μm, 5 μm, 1 μm, 60 nm, 40nm and 20 nm by taking into account the contribution of the primary photon beams and the electrons generated by them in LiF: Mg, Ti (TLD-100). The simulations were carried out by the code PENELOPE 2011. Using different histories of primary particles, for each energy beams the mean deposited energy is the same, but to achieve a statistical deviation lower than 1% the value of 108was fixed. We find that setting the values C1 = 0.1 C2 = 0.1 and Wcc = Wcr = 50 eV the time of simulation decreases around the 25%. The uncertainties (1 SD) in the specific energy increases with energy for all target sizes and decreases with target size, with values from 1.7 to 94% for 20 nm and between 0.1 and 0.8% for 10 μm. As expected, the specific and linear energies decrease with target size but not in a geometrical behavior.
{"title":"Effect of the Target Size in the Calculation of the Energy Deposited Using PENELOPE Code","authors":"B. Leal-Acevedo, P. G. Reyes-Romero, Fermín Castillo, I. Gamboa-deBuen","doi":"10.15415/JNP.2018.61011","DOIUrl":"https://doi.org/10.15415/JNP.2018.61011","url":null,"abstract":"The specific and linear energy was calculated in target sizes of 10 μm, 5 μm, 1 μm, 60 nm, 40nm and 20 nm by taking into account the contribution of the primary photon beams and the electrons generated by them in LiF: Mg, Ti (TLD-100). The simulations were carried out by the code PENELOPE 2011. Using different histories of primary particles, for each energy beams the mean deposited energy is the same, but to achieve a statistical deviation lower than 1% the value of 108was fixed. We find that setting the values C1 = 0.1 C2 = 0.1 and Wcc = Wcr = 50 eV the time of simulation decreases around the 25%. The uncertainties (1 SD) in the specific energy increases with energy for all target sizes and decreases with target size, with values from 1.7 to 94% for 20 nm and between 0.1 and 0.8% for 10 μm. As expected, the specific and linear energies decrease with target size but not in a geometrical behavior.","PeriodicalId":16534,"journal":{"name":"Journal of Nuclear Physics, Material Sciences, Radiation and Applications","volume":"1 1","pages":"67-70"},"PeriodicalIF":0.0,"publicationDate":"2018-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80689068","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. L. Flores, Puebla Mexico th south street, R. Palomino-Merino, E. Moreno-Barbosa, J.N. Domínguez-Kondo, V. Castaño, A. Sánchez, J. Golzarri, G. Espinosa
This work presents the development of an analysis of the potential radiological risk generated by alpha particles emitted by radon-222, content in a spring water, for the population that usually swims in the place and for the people who live near this spring. This spring is located in the state of Puebla. Several measurements in the water of this place by researchers from IF-UNAM showed that it contains an average radon concentration level of 70 Bq/m3. To evaluate this radiological risk, it has been developed a computational simulation to know the area and the height where the alpha particles deposit their energy to the medium, as well as the amount of energy that they transfer. This simulation was developed in the Geant4 scientific software and the calculations were executed in the supercomputer of the Laboratorio Nacional de Supercomputo del Sureste de Mexico of the BUAP. The results show that the energy deposit occurs within the superficial limits of the spring, between 7 and 8 meters high. This deposited is not only by the alpha particles, but also by the secondary particles that are generated by the interaction of alpha particles with the environment. Based on these results, it is confirmed that there is no radiological risk by energy deposit by alpha particles for the people.
{"title":"Analysis of the Energy Deposit in the Air by Radiation of Alpha Particles Emitted by the Water of a Spring Through the Geant4 Software","authors":"A. L. Flores, Puebla Mexico th south street, R. Palomino-Merino, E. Moreno-Barbosa, J.N. Domínguez-Kondo, V. Castaño, A. Sánchez, J. Golzarri, G. Espinosa","doi":"10.15415/JNP.2018.61010","DOIUrl":"https://doi.org/10.15415/JNP.2018.61010","url":null,"abstract":"This work presents the development of an analysis of the potential radiological risk generated by alpha particles emitted by radon-222, content in a spring water, for the population that usually swims in the place and for the people who live near this spring. This spring is located in the state of Puebla. Several measurements in the water of this place by researchers from IF-UNAM showed that it contains an average radon concentration level of 70 Bq/m3. To evaluate this radiological risk, it has been developed a computational simulation to know the area and the height where the alpha particles deposit their energy to the medium, as well as the amount of energy that they transfer. This simulation was developed in the Geant4 scientific software and the calculations were executed in the supercomputer of the Laboratorio Nacional de Supercomputo del Sureste de Mexico of the BUAP. The results show that the energy deposit occurs within the superficial limits of the spring, between 7 and 8 meters high. This deposited is not only by the alpha particles, but also by the secondary particles that are generated by the interaction of alpha particles with the environment. Based on these results, it is confirmed that there is no radiological risk by energy deposit by alpha particles for the people.","PeriodicalId":16534,"journal":{"name":"Journal of Nuclear Physics, Material Sciences, Radiation and Applications","volume":"15 1","pages":"61-66"},"PeriodicalIF":0.0,"publicationDate":"2018-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88576674","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}
L. Hallado, J. Poveda, E. Prieto, A. Guerrero, I. Álvarez, C. Cisneros
{"title":"Laser Radiation Effects on Adenine","authors":"L. Hallado, J. Poveda, E. Prieto, A. Guerrero, I. Álvarez, C. Cisneros","doi":"10.15415/JNP.2018.61018","DOIUrl":"https://doi.org/10.15415/JNP.2018.61018","url":null,"abstract":"","PeriodicalId":16534,"journal":{"name":"Journal of Nuclear Physics, Material Sciences, Radiation and Applications","volume":"556 1","pages":"103-108"},"PeriodicalIF":0.0,"publicationDate":"2018-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82968964","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}