In this study,we calculated the photon absorption cross sections of even–even neodymium(Nd)isotopes using the Dirac Quasiparticle Finite Amplitude Method(relativistic QFAM),combined with the Tiny Smearing Approximati...In this study,we calculated the photon absorption cross sections of even–even neodymium(Nd)isotopes using the Dirac Quasiparticle Finite Amplitude Method(relativistic QFAM),combined with the Tiny Smearing Approximation(TSA)method.This approach enables the efficient reproduction of experimental photon absorption data for both spherical and deformed nuclei.We demonstrate that relativistic QFAM calculations with any smearing parameter γ can be scaled using the TSA method,significantly reducing the computational cost.Our method was applied to Nd isotopes,with experimental data reproduced for ^(142,144,146,148,150)Nd and predictions for ^(152)Nd.By optimizing the three key parameters,the total χ^(2) between the calculations and experimental data was reduced by nearly an order of magnitude.Furthermore,the role of nuclear deformation in the Giant Dipole Resonance(GDR)structure was analyzed,highlighting its impact on the emergence of double peaks in the photon absorption cross sections of deformed nuclei.This work provides a robust microscopic approach to improve photonuclear data for applications in nuclear physics and astrophysics.展开更多
Based on the LINAC of BEPCII, a high-polarized, high bightness, energy-tunable, monoenergetic laser compton backscattering (LCS)gamma-ray source is under construction at IHEP. The gamma-ray energy range is from 1 MeV ...Based on the LINAC of BEPCII, a high-polarized, high bightness, energy-tunable, monoenergetic laser compton backscattering (LCS)gamma-ray source is under construction at IHEP. The gamma-ray energy range is from 1 MeV to 111 MeV. It is a powerful and hopeful researchplatform to reveal the underlying physics of the nuclear, the basic particles and the vacuum or to check the exist basic physical models, quantumelectrodynamic (QED) theories. In the platform, a 1.064 mm Nd:YAG laser system and a 10.6 mm CO_(2) laser system are employed. All the triggersignals to the laser system and the electron control system are from the only reference clock at the very beginning of the LINAC to make sure thetemporal synchronization. Two optical transition radiation (OTR) targets and two charged-couple devices (CCD) are used to monitor and to alignthe electron beam and the laser beam. With the LCS gamma-ray source, it is proposed to experimentally check the gamma-ray calibrations, thephoton-nuclear physics, nuclear astrophysics and some basic QED phenomena.展开更多
The efficient production of energetic γ photons is a significant physical process in the relativistic ultrashortpulse laser-plasma inducing photonuclear action. Based on the interaction of laser-solid-target, an anal...The efficient production of energetic γ photons is a significant physical process in the relativistic ultrashortpulse laser-plasma inducing photonuclear action. Based on the interaction of laser-solid-target, an analytical theory onstimulated γ photon emission from a hot electron firing the target-nucleus is developed by a relativistic full quantummethod. The emitting power or probability of γ photon in arbitrary space direction can be calculated for laser irradiatingsolid-target normally. It is valid only if the scatter-centre is immovable or its motion can be neglected compared withthat of the scattered electrons.展开更多
基金supported by the National Key Research and Development(R&D)Program(Nos.2022YFA1602403,2021YFA1601500)Key Program of the National Natural Science Foundation of China(No.12435007)+3 种基金the National Natural Science Foundation of China(Nos.12075104,12447106,and 12147101)the Basic Research Project of China National Nuclear Corporation(CNNC)(No.CNDC-JCYJ-202402)CNNC Youth Innovation Team Project Key Laboratory Fund,the Key Laboratory Fund Key Projects(No.JCKY2023201C153-5)Continuous Support Basic Scientific Research Project(BJ010261223282).
文摘In this study,we calculated the photon absorption cross sections of even–even neodymium(Nd)isotopes using the Dirac Quasiparticle Finite Amplitude Method(relativistic QFAM),combined with the Tiny Smearing Approximation(TSA)method.This approach enables the efficient reproduction of experimental photon absorption data for both spherical and deformed nuclei.We demonstrate that relativistic QFAM calculations with any smearing parameter γ can be scaled using the TSA method,significantly reducing the computational cost.Our method was applied to Nd isotopes,with experimental data reproduced for ^(142,144,146,148,150)Nd and predictions for ^(152)Nd.By optimizing the three key parameters,the total χ^(2) between the calculations and experimental data was reduced by nearly an order of magnitude.Furthermore,the role of nuclear deformation in the Giant Dipole Resonance(GDR)structure was analyzed,highlighting its impact on the emergence of double peaks in the photon absorption cross sections of deformed nuclei.This work provides a robust microscopic approach to improve photonuclear data for applications in nuclear physics and astrophysics.
基金This work was supported by National Natural Science Foundation of China(11655003)Innovation Project of IHEP(542017IHEPZZBS11820)This work was supported in part by the CAS Center for Excellence in Particle Physics(CCEPP).
文摘Based on the LINAC of BEPCII, a high-polarized, high bightness, energy-tunable, monoenergetic laser compton backscattering (LCS)gamma-ray source is under construction at IHEP. The gamma-ray energy range is from 1 MeV to 111 MeV. It is a powerful and hopeful researchplatform to reveal the underlying physics of the nuclear, the basic particles and the vacuum or to check the exist basic physical models, quantumelectrodynamic (QED) theories. In the platform, a 1.064 mm Nd:YAG laser system and a 10.6 mm CO_(2) laser system are employed. All the triggersignals to the laser system and the electron control system are from the only reference clock at the very beginning of the LINAC to make sure thetemporal synchronization. Two optical transition radiation (OTR) targets and two charged-couple devices (CCD) are used to monitor and to alignthe electron beam and the laser beam. With the LCS gamma-ray source, it is proposed to experimentally check the gamma-ray calibrations, thephoton-nuclear physics, nuclear astrophysics and some basic QED phenomena.
文摘The efficient production of energetic γ photons is a significant physical process in the relativistic ultrashortpulse laser-plasma inducing photonuclear action. Based on the interaction of laser-solid-target, an analytical theory onstimulated γ photon emission from a hot electron firing the target-nucleus is developed by a relativistic full quantummethod. The emitting power or probability of γ photon in arbitrary space direction can be calculated for laser irradiatingsolid-target normally. It is valid only if the scatter-centre is immovable or its motion can be neglected compared withthat of the scattered electrons.
