The Experts below are selected from a list of 117951 Experts worldwide ranked by ideXlab platform
Nowacki F. - One of the best experts on this subject based on the ideXlab platform.
-
The calculation of the neutrinoless double-beta Decay matrix element within the realistic shell model
HAL CCSD, 2020Co-Authors: Coraggio L., Gargano A., Itaco N., Mancino R., Nowacki F.Abstract:We approach the calculation of the nuclear matrix element of the neutrinoless double-beta Decay Process, considering the light-neutrino-exchange channel, by way of the realistic shell model. To this end, we start from a realistic nucleon-nucleon potential and then derive the effective shell-model Hamiltonian and neutrinoless double-beta Decay operator within the many-body perturbation theory. We focus on investigating the perturbative properties of the effective shell-model operator of such a Decay Process, aiming to establish the degree of reliability of our predictions. The contributions of the so-called short-range correlations and of the correction of Pauli-principle violations to the effective shell-model operator, the latter introduced in many-valence nucleon systems, are also taken into account. The subjects of our study are a few candidates to the neutrinoless double-beta Decay detection, in a mass interval ranging from A=48 up to A=136, whose spin- and spin-isospin-dependent Decay properties we have studied in previous works. Our results will be finally compared with shell-model calculations for the same set of nuclei
-
The calculation of the neutrinoless double-beta Decay matrix element within the realistic shell model
'American Physical Society (APS)', 2020Co-Authors: Coraggio L., Gargano A., Itaco N., Mancino R., Nowacki F.Abstract:We approach the calculation of the nuclear matrix element of the neutrinoless double-beta Decay Process, considering the light-neutrino-exchange channel, by way of the realistic shell model. To this end, we start from a realistic nucleon-nucleon potential and then derive the effective shell-model Hamiltonian and neutrinoless double-beta Decay operator within the many-body perturbation theory. We focus on investigating the perturbative properties of the effective shell-model operator of such a Decay Process, aiming to establish the degree of reliability of our predictions. The contributions of the so-called short-range correlations and of the correction of Pauli-principle violations to the effective shell-model operator, the latter introduced in many-valence nucleon systems, are also taken into account. The subjects of our study are a few candidates to the neutrinoless double-beta Decay detection, in a mass interval ranging from A=48 up to A=136, whose spin- and spin-isospin-dependent Decay properties we have studied in previous works. Our results will be finally compared with shell-model calculations for the same set of nuclei.Comment: 13 pages, 15 figures, 1 table, to be published in Physical Review
-
Calculation of the neutrinoless double-$\beta$ Decay matrix element within the realistic shell model
'American Physical Society (APS)', 2020Co-Authors: Coraggio L., Gargano A., Itaco N., Mancino R., Nowacki F.Abstract:International audienceWe approach the calculation of the nuclear matrix element of the neutrinoless double-β Decay Process, considering the light-neutrino-exchange channel, by way of the realistic shell model. To this end, we start from a realistic nucleon-nucleon potential and then derive the effective shell-model Hamiltonian and 0νββ Decay operator within the many-body perturbation theory. We focus on investigating the perturbative properties of the effective shell-model operator of such a Decay Process, aiming to establish the degree of reliability of our predictions. The contributions of the so-called short-range correlations and of the correction of Pauli-principle violations to the effective shell-model operator, the latter introduced in many-valence nucleon systems, are also taken into account. The subjects of our study are a few candidates to the 0νββ Decay detection, in a mass interval ranging from A=48 up to A=136, whose spin- and spin-isospin-dependent Decay properties we have studied in previous works. Our results provide evidence that the effect of the renormalization of the 0νββ-beta Decay operator on the values of the nuclear matrix elements is less relevant than what we have obtained in previous studies of the effective single-body Gamow-Teller transitions operating also in the two-neutrino double-β deca
Serdar Unlu - One of the best experts on this subject based on the ideXlab platform.
-
contributions of the isobar analogue states to the two neutrino double beta Decay Process
Nuclear Physics, 2012Co-Authors: Lutfi Arisoy, Serdar UnluAbstract:The two neutrino double beta Decay of 128, 130 Te isotopes to the ground state of the 128, 130 Xe isotopes has been calculated by including the contributions coming from the isobar analog states in the intermediate nuclei. The nuclear matrix elements have been computed by using the proton–neutron quasi-particle random phase approximation (pnQRPA). The broken isospin invariance of the nuclear part of the total nucleus Hamiltonian has been restored for the study of the isobar analogue excitations in the intermediate nuclei. The SU(4) symmetry violation in the shell model approximation has been considered for the investigation of the Gamow–Teller states. © 2012 Elsevier B.V. All rights reserved.
Coraggio L. - One of the best experts on this subject based on the ideXlab platform.
-
The calculation of the neutrinoless double-beta Decay matrix element within the realistic shell model
HAL CCSD, 2020Co-Authors: Coraggio L., Gargano A., Itaco N., Mancino R., Nowacki F.Abstract:We approach the calculation of the nuclear matrix element of the neutrinoless double-beta Decay Process, considering the light-neutrino-exchange channel, by way of the realistic shell model. To this end, we start from a realistic nucleon-nucleon potential and then derive the effective shell-model Hamiltonian and neutrinoless double-beta Decay operator within the many-body perturbation theory. We focus on investigating the perturbative properties of the effective shell-model operator of such a Decay Process, aiming to establish the degree of reliability of our predictions. The contributions of the so-called short-range correlations and of the correction of Pauli-principle violations to the effective shell-model operator, the latter introduced in many-valence nucleon systems, are also taken into account. The subjects of our study are a few candidates to the neutrinoless double-beta Decay detection, in a mass interval ranging from A=48 up to A=136, whose spin- and spin-isospin-dependent Decay properties we have studied in previous works. Our results will be finally compared with shell-model calculations for the same set of nuclei
-
The calculation of the neutrinoless double-beta Decay matrix element within the realistic shell model
'American Physical Society (APS)', 2020Co-Authors: Coraggio L., Gargano A., Itaco N., Mancino R., Nowacki F.Abstract:We approach the calculation of the nuclear matrix element of the neutrinoless double-beta Decay Process, considering the light-neutrino-exchange channel, by way of the realistic shell model. To this end, we start from a realistic nucleon-nucleon potential and then derive the effective shell-model Hamiltonian and neutrinoless double-beta Decay operator within the many-body perturbation theory. We focus on investigating the perturbative properties of the effective shell-model operator of such a Decay Process, aiming to establish the degree of reliability of our predictions. The contributions of the so-called short-range correlations and of the correction of Pauli-principle violations to the effective shell-model operator, the latter introduced in many-valence nucleon systems, are also taken into account. The subjects of our study are a few candidates to the neutrinoless double-beta Decay detection, in a mass interval ranging from A=48 up to A=136, whose spin- and spin-isospin-dependent Decay properties we have studied in previous works. Our results will be finally compared with shell-model calculations for the same set of nuclei.Comment: 13 pages, 15 figures, 1 table, to be published in Physical Review
-
Calculation of the neutrinoless double-$\beta$ Decay matrix element within the realistic shell model
'American Physical Society (APS)', 2020Co-Authors: Coraggio L., Gargano A., Itaco N., Mancino R., Nowacki F.Abstract:International audienceWe approach the calculation of the nuclear matrix element of the neutrinoless double-β Decay Process, considering the light-neutrino-exchange channel, by way of the realistic shell model. To this end, we start from a realistic nucleon-nucleon potential and then derive the effective shell-model Hamiltonian and 0νββ Decay operator within the many-body perturbation theory. We focus on investigating the perturbative properties of the effective shell-model operator of such a Decay Process, aiming to establish the degree of reliability of our predictions. The contributions of the so-called short-range correlations and of the correction of Pauli-principle violations to the effective shell-model operator, the latter introduced in many-valence nucleon systems, are also taken into account. The subjects of our study are a few candidates to the 0νββ Decay detection, in a mass interval ranging from A=48 up to A=136, whose spin- and spin-isospin-dependent Decay properties we have studied in previous works. Our results provide evidence that the effect of the renormalization of the 0νββ-beta Decay operator on the values of the nuclear matrix elements is less relevant than what we have obtained in previous studies of the effective single-body Gamow-Teller transitions operating also in the two-neutrino double-β deca
Irina Vladimirovna Krivosheina - One of the best experts on this subject based on the ideXlab platform.
-
nuclear double beta Decay fundamental particle physics hot dark matter and dark energy
arXiv: High Energy Physics - Phenomenology, 2010Co-Authors: H V Klapdorkleingrothaus, Irina Vladimirovna KrivosheinaAbstract:Nuclear double beta Decay, an extremely rare radioactive Decay Process, is - in one of its variants - one of the most exciting means of research into particle physics beyond the standard model. The large progress in sensitivity of experiments searching for neutrinoless double beta Decay in the last two decades - based largely on the use of large amounts of enriched source material in "active source experiments" - has lead to the observation of the occurrence of this Process in nature (on a 6.4 sigma level), with the largest half-life ever observed for a nuclear Decay Process (2.2 x 10^{25} y). This has fundamental consequences for particle physics - violation of lepton number, Majorana nature of the neutrino. These results are independent of any information on nuclear matrix elements (NME)*. It further leads to sharp restrictions for SUSY theories, sneutrino mass, right-handed W-boson mass, superheavy neutrino masses, compositeness, leptoquarks, violation of Lorentz invariance and equivalence principle in the neutrino sector. The masses of light-neutrinos are found to be degenerate, and to be at least 0.22 +- 0.02 eV. This fixes the contribution of neutrinos as hot dark matter to >=4.7% of the total observed dark matter. The neutrino mass determined might solve also the dark energy puzzle. *(It is briefly discussed how important NME for 0nubb Decay really are.)
-
nuclear double beta Decay fundamental particle physics hot dark matter and dark energy
Proceedings of the 7th International Heidelberg Conference on Dark 2009, 2009Co-Authors: H V Klapdorkleingrothaus, Irina Vladimirovna KrivosheinaAbstract:Nuclear double beta Decay, an extremely rare radioactive Decay Process, is in one of its variants one of the most exciting means of research into particle physics beyond the standard model. The large progress in sensitivity of experiments searching for neutrinoless double beta Decay in the last two decades based largely on the use of large amounts of enriched source material in “active source experiments” has lead to the observation of the occurrence of this Process in nature (on a 6.4 sigma level), with the largest half-life ever observed for a nuclear Decay Process (2.2×1025 y). This has fundamental consequences for particle physics violation of lepton number, Majorana nature of the neutrino. These results are independent of any information on nuclear matrix elements (NME) ∗. It further leads to sharp restrictions for SUSY theories, sneutrino mass, right-handed W-boson mass, superheavy neutrino masses, compositeness, leptoquarks, violation of Lorentz invariance and equivalence principle in the neutrino sector. The masses of light-neutrinos are found to be degenerate, and to be at least 0.22±0.02 eV. This fixes the contribution of neutrinos as hot dark matter to ≥4.7% of the total observed dark matter. The neutrino mass determined might solve also the dark energy puzzle.
James A R Samson - One of the best experts on this subject based on the ideXlab platform.
-
auger resonance Decay Process in ar 2p shell excitation and ionization
Physical Review A, 1998Co-Authors: Wayne C Stolte, James A R SamsonAbstract:The production and subsequent autoionization of the Ar(D2)6d8 satellite state that is formed either by shake-up or recapture during the Auger Decay of a 2p vacancy in Ar has been studied by photoelectron spectroscopy in the energy region from 243 to 256 eV. The creation of near zero energy electrons below and immediately above the Ar 2p ionization threshold is discussed. Some ambiguous points in previous studies are clarified. @S1050-2947~98!12609-4#
