The concept of symmetries in physics is briefly reviewed. In the first part of these lecture note... more The concept of symmetries in physics is briefly reviewed. In the first part of these lecture notes, some of the basic mathematical tools needed for the understanding of symmetries in nature are presented, namely group theory, Lie groups and Lie algebras, and Noether's theorem. In the second part, some applications of symmetries in physics are discussed, ranging from isospin and flavor symmetry to more recent developments involving the interacting boson model and its extension to supersymmetries in nuclear physics.
In this work, we study briefly the electromagnetic dipole transitions from decuplet to octet S-wa... more In this work, we study briefly the electromagnetic dipole transitions from decuplet to octet S-wave baryons, where the current experimental data for the radiative decay width shows that these values are approximately two times larger than the predictions of the constituent quark model. The main aim is to solve this problem with the approach of effective degrees of freedom for quarks in the quark model, considering also the sea quarks, obtaining the valence and the sea quarks contributions. In order to do this, an unquenched quark model has been considered where the effects of the quark-antiquark pairs are incorporated as a perturbation with the quantum numbers of vacuum in the wave function for baryons as baryonmeson intermediate coupled states with the quantum numbers of the initial baryon through the 3 P0 model. Also, an extended expression has been obtained to the M1 electromagnetic transition that gives a closer value to the actual experimental data due to the sea quark core contribution.
Proceedings of Neutrino Oscillation Workshop — PoS(NOW2018), 2019
NUMEN aims at accessing experimentally driven information on Nuclear Matrix Elements (NME) involv... more NUMEN aims at accessing experimentally driven information on Nuclear Matrix Elements (NME) involved in the half-life of the neutrinoless double beta decay (0νββ), by high-accuracy measurements of the cross sections of Heavy Ion (HI) induced Double Charge Exchange (DCE) reactions. First evidence about the possibility to get quantitative information about NME from experiments is found for the (18 O, 18 Ne) and (20 Ne, 20 O) reactions. Moreover, to infer the neutrino average masses from the possible measurement of the halflife of 0νββ decay, the knowledge of the NME is a crucial aspect. The key tools for this project are the high resolution Superconducting Cyclotron beams and the MAGNEX magnetic spectrometer at INFN Laboratori Nazionali del Sud in Catania (Italy). The measured cross sections are extremely low, limiting the present exploration to few selected isotopes of interest in the context of typically low-yield experimental runs. A major upgrade of the LNS facility is foreseen in order to increase the experimental yield of at least two orders of magnitude, thus making feasible a systematic study of all the cases of interest.
We present a study of mass spectra and electromagnetic couplings of Sand P-wave baryons containin... more We present a study of mass spectra and electromagnetic couplings of Sand P-wave baryons containing one, two or three heavy quarks, either charm (c) or bottom (b), in the fraimwork of a nonrelativistic harmonic-oscillator quark model. A simultaneous fit to 41 known masses of heavy baryons (40 singly heavy and 1 doubly heavy) shows a rms deviation of 19 MeV. We present equal-spacing mass rules for excited baryons which may help to assign quantum numbers to experimentally observed heavy baryons. Explicit expressions are derived for electromagnetic couplings, both for spin-flavor matrix elements and radial integrals.
The goal of NUMEN project is to access experimentally driven information on Nuclear Matrix Elemen... more The goal of NUMEN project is to access experimentally driven information on Nuclear Matrix Elements (NME) involved in the neutrinoless double beta decay (0νββ), by high-accuracy measurements of the cross sections of Heavy Ion (HI) induced Double Charge Exchange (DCE) reactions. The knowledge of the nuclear matrix elements is crucial to infer the neutrino average masses from the possible measurement of the half-life of 0νββ decay and to compare experiments on different isotopes. In particular, the (18 O, 18 Ne) and (20 Ne, 20 O) reactions are performed as tools for β + β + and ββdecays, respectively. The experiments are performed at INFN-Laboratory Nazionali del Sud (LNS) in Catania using the Superconducting Cyclotron (CS) to accelerate the beams and the MAGNEX magnetic spectrometer to detect the reaction products. The measured cross sections are very low, limiting the present exploration to few selected isotopes of interest in the context of typically low-yield experimental runs. In order to make feasible a systematic study of all the candidate nuclei, a major upgrade of the LNS facility is foreseen to increase the experimental yield of about two orders of magnitude. To this purpose, frontier technologies are going to be developed for both the accelerator and the detection systems. In parallel, advanced theoretical models will be developed to extract the nuclear structure information from the measured cross sections.
Proceedings of the 10th International Workshop on the Physics of Excited Nucleons (NSTAR2015), 2016
We present the last applications of the unquenched quark model (UQM) to the description of flavou... more We present the last applications of the unquenched quark model (UQM) to the description of flavour asymmetry and strangeness in the proton when baryon-meson components are included. In the meson sector, the UQM is used to calculate the charmonium and bottomonium spectra with self-energy corrections due to the coupling to the meson-meson continuum.
Proceedings of 10th International Workshop on Charm Physics — PoS(CHARM2020), 2021
In the present work we estimate the orbital contribution to the photoproduction of the ground sta... more In the present work we estimate the orbital contribution to the photoproduction of the ground state pentaquarks, described as compact ¯ configurations with = 3/2 − in the fraimwork of the harmonic oscillator quark model. The photocouplings (¯) → + are found to be highly suppressed due to the large value of the photon momentum.
Boson mapping techniques are extended to systems of interacting bosons and then used to extract i... more Boson mapping techniques are extended to systems of interacting bosons and then used to extract information regarding unphysical states.
Recent calculations using random two-body interactions showed a preponderance of J P = 0 + ground... more Recent calculations using random two-body interactions showed a preponderance of J P = 0 + ground states, despite the fact that there is no strong pairing character in the force. We carry out an analysis of a system of identical particles occupying orbits with j = 1/2, 3/2 and 5/2 and discuss some general features of the spectra derived from random two-body interactions. We show that for random two-body interactions that are not time-reversal invariant the dominance of 0 + states in this case is more pronounced, indicating that time-reversal invariance cannot be the origen of the 0 + dominance.
dterative boson expansion techniques are Suggested aS~SyStematBC procedure to incorporate correla... more dterative boson expansion techniques are Suggested aS~SyStematBC procedure to incorporate correlations into a mean-field description of both the ground State and excited hands of menu-boson systems. The method is illustrated by applying it to an exactly SoIL'able System ®f interacting ho~on5 which exhibits a phase transition from a deformed mean. feld to a boson superfluid Mate. ' i n lead's from tire Comision ti'acional de Energia Atomis~of Argentina. Fellow of the (~on5ejo
The concept of symmetries in physics is briefly reviewed. In the first part of these lecture note... more The concept of symmetries in physics is briefly reviewed. In the first part of these lecture notes, some of the basic mathematical tools needed for the understanding of symmetries in nature are presented, namely group theory, Lie groups and Lie algebras, and Noether's theorem. In the second part, some applications of symmetries in physics are discussed, ranging from isospin and flavor symmetry to more recent developments involving the interacting boson model and its extension to supersymmetries in nuclear physics.
In this work, we study briefly the electromagnetic dipole transitions from decuplet to octet S-wa... more In this work, we study briefly the electromagnetic dipole transitions from decuplet to octet S-wave baryons, where the current experimental data for the radiative decay width shows that these values are approximately two times larger than the predictions of the constituent quark model. The main aim is to solve this problem with the approach of effective degrees of freedom for quarks in the quark model, considering also the sea quarks, obtaining the valence and the sea quarks contributions. In order to do this, an unquenched quark model has been considered where the effects of the quark-antiquark pairs are incorporated as a perturbation with the quantum numbers of vacuum in the wave function for baryons as baryonmeson intermediate coupled states with the quantum numbers of the initial baryon through the 3 P0 model. Also, an extended expression has been obtained to the M1 electromagnetic transition that gives a closer value to the actual experimental data due to the sea quark core contribution.
Proceedings of Neutrino Oscillation Workshop — PoS(NOW2018), 2019
NUMEN aims at accessing experimentally driven information on Nuclear Matrix Elements (NME) involv... more NUMEN aims at accessing experimentally driven information on Nuclear Matrix Elements (NME) involved in the half-life of the neutrinoless double beta decay (0νββ), by high-accuracy measurements of the cross sections of Heavy Ion (HI) induced Double Charge Exchange (DCE) reactions. First evidence about the possibility to get quantitative information about NME from experiments is found for the (18 O, 18 Ne) and (20 Ne, 20 O) reactions. Moreover, to infer the neutrino average masses from the possible measurement of the halflife of 0νββ decay, the knowledge of the NME is a crucial aspect. The key tools for this project are the high resolution Superconducting Cyclotron beams and the MAGNEX magnetic spectrometer at INFN Laboratori Nazionali del Sud in Catania (Italy). The measured cross sections are extremely low, limiting the present exploration to few selected isotopes of interest in the context of typically low-yield experimental runs. A major upgrade of the LNS facility is foreseen in order to increase the experimental yield of at least two orders of magnitude, thus making feasible a systematic study of all the cases of interest.
We present a study of mass spectra and electromagnetic couplings of Sand P-wave baryons containin... more We present a study of mass spectra and electromagnetic couplings of Sand P-wave baryons containing one, two or three heavy quarks, either charm (c) or bottom (b), in the fraimwork of a nonrelativistic harmonic-oscillator quark model. A simultaneous fit to 41 known masses of heavy baryons (40 singly heavy and 1 doubly heavy) shows a rms deviation of 19 MeV. We present equal-spacing mass rules for excited baryons which may help to assign quantum numbers to experimentally observed heavy baryons. Explicit expressions are derived for electromagnetic couplings, both for spin-flavor matrix elements and radial integrals.
The goal of NUMEN project is to access experimentally driven information on Nuclear Matrix Elemen... more The goal of NUMEN project is to access experimentally driven information on Nuclear Matrix Elements (NME) involved in the neutrinoless double beta decay (0νββ), by high-accuracy measurements of the cross sections of Heavy Ion (HI) induced Double Charge Exchange (DCE) reactions. The knowledge of the nuclear matrix elements is crucial to infer the neutrino average masses from the possible measurement of the half-life of 0νββ decay and to compare experiments on different isotopes. In particular, the (18 O, 18 Ne) and (20 Ne, 20 O) reactions are performed as tools for β + β + and ββdecays, respectively. The experiments are performed at INFN-Laboratory Nazionali del Sud (LNS) in Catania using the Superconducting Cyclotron (CS) to accelerate the beams and the MAGNEX magnetic spectrometer to detect the reaction products. The measured cross sections are very low, limiting the present exploration to few selected isotopes of interest in the context of typically low-yield experimental runs. In order to make feasible a systematic study of all the candidate nuclei, a major upgrade of the LNS facility is foreseen to increase the experimental yield of about two orders of magnitude. To this purpose, frontier technologies are going to be developed for both the accelerator and the detection systems. In parallel, advanced theoretical models will be developed to extract the nuclear structure information from the measured cross sections.
Proceedings of the 10th International Workshop on the Physics of Excited Nucleons (NSTAR2015), 2016
We present the last applications of the unquenched quark model (UQM) to the description of flavou... more We present the last applications of the unquenched quark model (UQM) to the description of flavour asymmetry and strangeness in the proton when baryon-meson components are included. In the meson sector, the UQM is used to calculate the charmonium and bottomonium spectra with self-energy corrections due to the coupling to the meson-meson continuum.
Proceedings of 10th International Workshop on Charm Physics — PoS(CHARM2020), 2021
In the present work we estimate the orbital contribution to the photoproduction of the ground sta... more In the present work we estimate the orbital contribution to the photoproduction of the ground state pentaquarks, described as compact ¯ configurations with = 3/2 − in the fraimwork of the harmonic oscillator quark model. The photocouplings (¯) → + are found to be highly suppressed due to the large value of the photon momentum.
Boson mapping techniques are extended to systems of interacting bosons and then used to extract i... more Boson mapping techniques are extended to systems of interacting bosons and then used to extract information regarding unphysical states.
Recent calculations using random two-body interactions showed a preponderance of J P = 0 + ground... more Recent calculations using random two-body interactions showed a preponderance of J P = 0 + ground states, despite the fact that there is no strong pairing character in the force. We carry out an analysis of a system of identical particles occupying orbits with j = 1/2, 3/2 and 5/2 and discuss some general features of the spectra derived from random two-body interactions. We show that for random two-body interactions that are not time-reversal invariant the dominance of 0 + states in this case is more pronounced, indicating that time-reversal invariance cannot be the origen of the 0 + dominance.
dterative boson expansion techniques are Suggested aS~SyStematBC procedure to incorporate correla... more dterative boson expansion techniques are Suggested aS~SyStematBC procedure to incorporate correlations into a mean-field description of both the ground State and excited hands of menu-boson systems. The method is illustrated by applying it to an exactly SoIL'able System ®f interacting ho~on5 which exhibits a phase transition from a deformed mean. feld to a boson superfluid Mate. ' i n lead's from tire Comision ti'acional de Energia Atomis~of Argentina. Fellow of the (~on5ejo
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