Home [31–40] << 41 42 43 44 45 46 47 48 49 50 >> [51–60]
List View
 | 
Citations
 | 
Details
   web
Records
Author Piriz, G.H.; Gonzalez-Sprinberg, G.A.; Ballester, F.; Vijande, J.
Title Dosimetry of Large Field Valencia applicators for Cobalt-60-based brachytherapy Type Journal Article
Year 2024 Publication Medical Physics Abbreviated Journal Med. Phys.
Volume 51 Issue Pages 5094-5098
Keywords dosimetry; Monte Carlo; skin brachytherapy; Valencia applicators
Abstract (up) BackgroundNon-melanoma skin cancer is one of the most common types of cancer and one of the main approaches is brachytherapy. For small lesions, the treatment of this cancer with brachytherapy can be done with two commercial applicators, one of these is the Large Field Valencia Applicators (LFVA).PurposeThe aim of this study is to test the capabilities of the LFVA to use clinically 60Co sources instead of the 192Ir ones. This study was designed for the same dwell positions and weights for both sources.MethodsThe Penelope Monte Carlo code was used to evaluate dose distribution in a water phantom when a 60Co source is considered. The LFVA design and the optimized dwell weights reported for the case of 192Ir are maintained with the only exception of the dwell weight of the central position, that was increased. 2D dose distributions, field flatness, symmetry and the leakage dose distribution around the applicator were calculated.ResultsWhen comparing the dose distributions of both sources, field flatness and symmetry remain unchanged. The only evident difference is an increase of the penumbra regions for all depths when using the 60Co source. Regarding leakage, the maximum dose within the air volume surrounding the applicator is in the order of 20% of the prescription dose for the 60Co source, but it decreases to less than 5% at about 1 cm distance.ConclusionsFlatness and symmetry remains unaltered as compared with 192Ir sources, while an increase in leakage has been observed. This proves the feasibility of using the LFVA in a larger range of clinical applications.
Address [Piriz, Gustavo H.; Gonzalez-Sprinberg, Gabriel A.] Univ Republica, Fac Sci, Med Phys Unit, Montevideo, Uruguay, Email: ghpiriz@gmail.com
Corporate Author Thesis
Publisher Wiley Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0094-2405 ISBN Medium
Area Expedition Conference
Notes WOS:001187737100001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6011
Permanent link to this record
 
 
Author Gargalionis, J.; Herrero-Garcia, J.; Schmidt, M.A.
Title Model-independent estimates for loop-induced baryon-number-violating nucleon decays Type Journal Article
Year 2024 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 06 Issue 6 Pages 182 - 52pp
Keywords Baryon/Lepton Number Violation; SMEFT
Abstract (up) Baryon number is an accidental symmetry of the Standard Model (SM) Lagrangian that so far has been measured to be exactly preserved, although it is expected to be violated at higher energies. In this work we compute order-of-magnitude estimates for the matching contributions of generic ultraviolet models to effective operators that generate nucleon decay processes. This is done in a systematic and automated way using operators constructed from SM fields up to dimension nine and working in a framework that has proved useful in the study of lepton-number violation. For each of the operators we derive estimates for the rates of different nucleon-decay channels. These allow us to establish model-independent lower bounds on the underlying new-physics scale and identify potential correlations between the various decay modes. The results are most relevant for families of models that generate the considered operator. This analysis is especially timely given the expected future sensitivities in numerous experiments such as Hyper-K, DUNE, JUNO and THEIA.
Address [Gargalionis, John; Herrero-Garcia, Juan] Univ Valencia, Dept Fis Teor, Burjassot 46100, Spain, Email: john.gargalionis@ific.uv.es;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:001257098800002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6166
Permanent link to this record
 
 
Author Dombos, A.C.; Spyrou, A.; Naqvi, F.; Quinn, S.J.; Liddick, S.N.; Algora, A.; Baumann, T.; Brett, J.; Crider, B.P.; DeYoung, P.A.; Ginter, T.; Gombas, J.; Kwan, E.; Lyons, S.; Ong, W.J.; Palmisano, A.; Pereira, J.; Prokop, C.J.; Scriven, D.P.; Simon, A.; Smith, M.K.; Sumithrarachchi, C.S.
Title beta-decay half-lives of neutron-rich nuclides in the A=100-110 mass region Type Journal Article
Year 2019 Publication Physical Review C Abbreviated Journal Phys. Rev. C
Volume 99 Issue 1 Pages 015802 - 8pp
Keywords
Abstract (up) beta-decay half-lives of neutron-rich nuclides in the A = 100-110 mass region have been measured using an implantation station installed inside of the Summing NaI(T1) (SuN) detector at the National Superconducting Cyclotron Laboratory. Accurate half-lives for these nuclides are important for nuclear astrophysics, nuclear structure, and nuclear technology. The half-lives from the present work are compared with previous measurements, showing overall good agreement.
Address [Dombos, A. C.; Spyrou, A.; Naqvi, F.; Quinn, S. J.; Liddick, S. N.; Baumann, T.; Crider, B. P.; Ginter, T.; Kwan, E.; Lyons, S.; Ong, W. -J.; Palmisano, A.; Pereira, J.; Prokop, C. J.; Smith, M. K.; Sumithrarachchi, C. S.] Michigan State Univ, Natl Superconducting Cyclotron Lab, E Lansing, MI 48824 USA, Email: dombos@nscl.msu.edu
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9985 ISBN Medium
Area Expedition Conference
Notes WOS:000455685700006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3876
Permanent link to this record
 
 
Author Yokoyama, R. et al; Tain, J.L.; Algora, A.; Agramunt, J.; Domingo-Pardo, C.; Morales, A.I.; Rubio, B.; Tolosa-Delgado, A.
Title β-delayed neutron emissions from N > 50 gallium isotopes Type Journal Article
Year 2023 Publication Physical Review C Abbreviated Journal Phys. Rev. C
Volume 108 Issue 6 Pages 064307 - 15pp
Keywords
Abstract (up) beta-delayed gamma-neutron spectroscopy has been performed on the decay of A=84 to 87 gallium isotopes at the RI-beam Factory at the RIKEN Nishina Center using a high-efficiency array of 3He neutron counters (BRIKEN). beta-2n-gamma events were measured in the decays of all of the four isotopes for the first time, which is direct evidence for populating the excited states of two-neutron daughter nuclei. Detailed decay schemes with the gamma branching ratios were obtained for these isotopes, and the neutron emission probabilities (P-xn) were updated from the previous study. Hauser-Feshbach statistical model calculations were performed to understand the experimental branching ratios. We found that the P-1n and P-2n values are sensitive to the nuclear level densities of 1n daughter nuclei and showed that the statistical model reproduced the P-2n/P-1n ratio better when experimental levels plus shell-model level densities fit by the Gilbert-Cameron formula were used as the level-density input. We also showed the neutron and gamma branching ratios are sensitive to the ground-state spin of the parent nucleus. Our statistical model analysis suggested J <= 3 for the unknown ground-state spin of the odd-odd nucleus Ga-86, from the I gamma(4(+)-> 2(+))/I-gamma(2(+)-> 0(+)) ratio of Ga-84 and the P-2n/P-1n ratio. These results show the necessity of detailed understanding of the decay scheme, including data from neutron spectroscopy, in addition to gamma measurements of the multineutron emitters.
Address [Yokoyama, R.; Grzywacz, R.; Rasco, B. C.; Brewer, N.; Heideman, J.; King, T. T.; Madurga, M.; Singh, M.] Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA, Email: yokoyama@cns.s.u-tokyo.ac.jp
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9985 ISBN Medium
Area Expedition Conference
Notes WOS:001159167500001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5939
Permanent link to this record
 
 
Author Dimitriou, P. et al; Tain, J.L.; Algora, A.
Title Development of a Reference Database for Beta-Delayed Neutron Emission Type Journal Article
Year 2021 Publication Nuclear Data Sheets Abbreviated Journal Nucl. Data Sheets
Volume 173 Issue Pages 144-238
Keywords
Abstract (up) Beta-delayed neutron emission is important for nuclear structure and astrophysics as well as for reactor applications. Significant advances in nuclear experimental techniques in the past two decades have led to a wealth of new measurements that remain to be incorporated in the databases. We report on a coordinated effort to compile and evaluate all the available beta-delayed neutron emission data. The different measurement techniques have been assessed and the data have been compared with semi-microscopic and microscopic-macroscopic models. The new microscopic database has been tested against aggregate total delayed neutron yields, time-dependent group parameters in 6-and 8-group re-presentation, and aggregate delayed neutron spectra. New recommendations of macroscopic delayed-neutron data for fissile materials of interest to applications are also presented.
Address [Dimitriou, P.; Verpelli, M.] IAEA, NAPC Nucl Data Sect, A-1400 Vienna, Austria, Email: p.dimitriou@iaea.org
Corporate Author Thesis
Publisher Academic Press Inc Elsevier Science Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0090-3752 ISBN Medium
Area Expedition Conference
Notes WOS:000647012500006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4828
Permanent link to this record
 
 
Author Yokoyama, R. et al; Tain, J.L.; Algora, A.; Agramunt, J.; Domingo-Pardo, C.; Morales, A.I.; Rubio, B.; Tolosa-Delgado, A.
Title Strong one-neutron emission from two-neutron unbound states in beta decays of the r-process nuclei Ga-86,Ga-87 Type Journal Article
Year 2019 Publication Physical Review C Abbreviated Journal Phys. Rev. C
Volume 100 Issue 3 Pages 031302 - 6pp
Keywords
Abstract (up) beta-delayed one-neutron and two-neutron branching ratios (P-1n and P-2n) have been measured in the decay of A = 84 to 87 Ga isotopes at the Radioactive-Isotope Beam Factory (RIBF) at the RIKEN Nishina Center using a high-efficiency array of He-3 neutron counters (BRIKEN). Two-neutron emission was observed in the decay of Ga-84,Ga-85,Ga-87 for the first time and the branching ratios were measured to be P-2n = 1.6(2)%, 1.3(2)%, and 10.2(28)(stat)(5)(sys)%, respectively. One-neutron branching ratio of Ga-87 (P-1n = 81(9)(stat)(8)(sys)%) and half-life of 29(4) ms were measured for the first time. The branching ratios of Ga-86 were also measured to be P-1n = 74(2)(stat)(8)(sys)% and 16.2(9)(stat)(6)(sys)% with better precision than a previous study. The observation that P-1n > P-2n for both Ga-86,Ga-87 was unexpected and is interpreted as a signature of dominating one-neutron emission from the two-neutron unbound excited states in Ge-86,Ge-87. In order to interpret the experimental results, shell-model and Hauser-Feshbach statistical model calculations of delayed particle and gamma-ray emission probabilities were performed. This model framework reproduces the experimental results. The shell model alone predicts P-2n significantly larger than P-1n for the Ga-87 decay, and it is necessary to invoke a statistical description to successfully explain the observation that P-1n > P-2n. Our new results demonstrate the relevance and importance of a statistical description of neutron emission for the prediction of the decay properties of multineutron emitters and that it must be included in the r-process modeling.
Address [Yokoyama, R.; Grzywacz, R.; Rasco, B. C.; Brewer, N.; Heideman, J.; King, T. T.; Madurga, M.; Singh, M.] Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA, Email: ryokoyam@utk.edu
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9985 ISBN Medium
Area Expedition Conference
Notes WOS:000486641000001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4145
Permanent link to this record
 
 
Author Ding, G.J.; Nath, N.; Srivastava, R.; Valle, J.W.F.
Title Status and prospects of 'bi-large' leptonic mixing Type Journal Article
Year 2019 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 796 Issue Pages 162-167
Keywords
Abstract (up) Bi-large patterns for the leptonic mixing matrix are confronted with current neutrino oscillation data. We analyse the status of these patterns and determine, through realistic simulations, the potential of the upcoming long-baseline experiment DUNE in testing bi-large ansatze and discriminating amongst them.
Address [Ding, Gui-Jun] Univ Sci & Technol China, Interdisciplinary Ctr Theoret Study, Hefei 230026, Anhui, Peoples R China, Email: dinggj@ustc.edu.cn;
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000483426200024 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4132
Permanent link to this record
 
 
Author Anderson, P.R.; Clark, R.D.; Fabbri, A.; Good, M.R.R.
Title Late time approach to Hawking radiation: Terms beyond leading order Type Journal Article
Year 2019 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 100 Issue 6 Pages 061703 - 5pp
Keywords
Abstract (up) Black hole evaporation is studied using wave packets for the modes. These allow for approximate frequency and time resolution. The leading order late time behavior gives the well-known Hawking radiation that is independent of how the black hole formed. The focus here is on the higher order terms and the rate at which they damp at late times. Some of these terms carry information about how the black hole formed. A general argument is given which shows that the damping is significantly slower (power law) than what might be naively expected from a stationary phase approximation (exponential). This result is verified by numerical calculations in the cases of 2D and 4D black holes that form from the collapse of a null shell.
Address [Anderson, Paul R.; Clark, Raymond D.] Wake Forest Univ, Dept Phys, Winston Salem, NC 27109 USA, Email: anderson@wfu.edu;
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000487736400001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4151
Permanent link to this record
 
 
Author Arnault, P.; Pepper, B.; Perez, A.
Title Quantum walks in weak electric fields and Bloch oscillations Type Journal Article
Year 2020 Publication Physical Review A Abbreviated Journal Phys. Rev. A
Volume 101 Issue 6 Pages 062324 - 12pp
Keywords
Abstract (up) Bloch oscillations appear when an electric field is superimposed on a quantum particle that evolves on a lattice with a tight-binding Hamiltonian (TBH), i.e., evolves via what we call an electric TBH; this phenomenon will be referred to as TBH Bloch oscillations. A similar phenomenon is known to show up in so-called electric discrete-time quantum walks (DQWs) [C. Cedzich et al., Phys. Rev. Lett. 111, 160601 (2013);] this phenomenon will be referred to as DQW Bloch oscillations. This similarity is particularly salient when the electric field of the DQW is weak. For a wide, i.e., spatially extended, initial condition, one numerically observes semiclassical oscillations, i.e., oscillations of a localized particle, for both the electric TBH and the electric DQW. More precisely, the numerical simulations strongly suggest that the semiclassical DQW Bloch oscillations correspond to two counterpropagating semiclassical TBH Bloch oscillations. In this work it is shown that, under certain assumptions, the solution of the electric DQW for a weak electric field and a wide initial condition is well approximated by the superposition of two continuous-time expressions, which are counterpropagating solutions of an electric TBH whose hopping amplitude is the cosine of the arbitrary coin-operator mixing angle. In contrast, if one wishes the continuous-time approximation to hold for spatially localized initial conditions, one needs at least the DQW to be lazy, as suggested by numerical simulations and by the fact that this has been proven in the case of a vanishing electric field [F. W. Strauch, Phys. Rev. A 74, 030301(R) (2006)].
Address [Arnault, Pablo; Pepper, Benjamin; Perez, A.] Univ Valencia, CSIC, Dept Fis Teor, Cerrer Dr Moliner 50, Burjassot 46100, Spain, Email: pablo.arnault@ific.uv.es;
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1050-2947 ISBN Medium
Area Expedition Conference
Notes WOS:000541400900002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4431
Permanent link to this record
 
 
Author Carcamo Hernandez, A.E.; Hati, C.; Kovalenko, S.; Valle, J.W.F.; Vaquera-Araujo, C.A.
Title Scotogenic neutrino masses with gauged matter parity and gauge coupling unification Type Journal Article
Year 2022 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 03 Issue 3 Pages 034 - 25pp
Keywords Beyond Standard Model; Gauge Symmetry; Neutrino Physics
Abstract (up) Building up on previous work we propose a Dark Matter (DM) model with gauged matter parity and dynamical gauge coupling unification, driven by the same physics responsible for scotogenic neutrino mass generation. Our construction is based on the extended gauge group SU(3)(c) circle times SU(3)(L) circle times U(1)(X) circle times U(1)(N), whose spontaneous breaking leaves a residual conserved matter parity, M-P, stabilizing the DM particle candidates of the model. The key role is played by Majorana SU(3) (L)-octet leptons, allowing the successful gauge coupling unification and a one-loop scotogenic neutrino mass generation. Theoretical consistency allows for a plethora of new particles at the less than or similar to O(10) TeV scale, hence accessible to future collider and low-energy experiments.
Address [Carcamo Hernandez, A. E.] Univ Tecn Federico Santa Maria, Casilla 110-5, Valparaiso, Chile, Email: antonio.carcamo@usm.cl;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000766168700014 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5162
Permanent link to this record