Based on the new screening model, this paper discusses the influence of superstrong magnetic fields on nuclear energy generation rates on the surface of magnetars. The obtained result shows that the superstrong magnet...Based on the new screening model, this paper discusses the influence of superstrong magnetic fields on nuclear energy generation rates on the surface of magnetars. The obtained result shows that the superstrong magnetic fields can increase the nuclear energy generation rates by many orders of magnitude. The enhancement may have a significant influence for further study of the magnetars, especially for the cooling, the x-ray luminosity observation and the evolution of the magnetars.展开更多
The electron capture timescale may be shorter than hydrodynamic timescale in inner iron core of core-collapse supernova according to a recent new idea. Based on the new idea, this paper carries out a numerical simulat...The electron capture timescale may be shorter than hydrodynamic timescale in inner iron core of core-collapse supernova according to a recent new idea. Based on the new idea, this paper carries out a numerical simulation on supernova explosion for the progenitor model Ws15M. The numerical result shows that the size of proto-neutron star has a significant change （decrease about 20%）, which may affects the propagation of the shock wave and the final explosion energy.展开更多
By adjusting the pressure grads in the stage of formation of the shock wave, a successful prompt explosion process has been numerically simulated through a progenitor model of 15Msolar, in which the effects of pressur...By adjusting the pressure grads in the stage of formation of the shock wave, a successful prompt explosion process has been numerically simulated through a progenitor model of 15Msolar, in which the effects of pressure grads on various convections, including the Rayleigh-Taloy （R-T） convection, the lepton driven convection and the negative entropy grads driven convection, in an inner core are analysed. The simulation results showthat the increase of the pressure grads in the inner core region may cause a powerful convection, which causes energy transfer from the inner core to the shock wave rapidly and efficiently.展开更多
Previous studies have shown that 33S（p,γ）34Cl is the most important reaction that affects the abundance of 33S in the product of nova nucleosynthesis. In this paper, a more accurate thermonuclear reaction rate of ...Previous studies have shown that 33S（p,γ）34Cl is the most important reaction that affects the abundance of 33S in the product of nova nucleosynthesis. In this paper, a more accurate thermonuclear reaction rate of 33S（p, γ）34Cl in the nova is calculated based on the newly measured 34C1 nuclear resonance levels. The electron screening correction and the non-resonance and narrow-resonance contributions are considered. The calculations are also combined with the recent observational data of nova V1065 Centauri and show that the thermonuclear reaction rates of 33S（p, γ） 34C1 are significantly different in the improved method. Because these results can affect the isotopic ratio of sulfur in the nova ejecta significantly, we make an estimate of the values of 328/33S and 338/338Q, which can be used as a diagnostic tool for the novae.展开更多
Constituent quark mass model is adopted as a tentative one to study the phase transition between two-flavour quark matter and more stable three-flavour quark matter in the core of supernovae. The result shows that the...Constituent quark mass model is adopted as a tentative one to study the phase transition between two-flavour quark matter and more stable three-flavour quark matter in the core of supernovae. The result shows that the transition has a significant influence on the increasing of the core temperature, the neutrino abundance and the neutrino energies, which contributes to the enhancement of the successful probability of supernova explosion. However, the equilibrium values of these parameters （except the temperature） from the constituent quark mass model in this work are slightly bigger than those obtained from the other model. And we find that the constituent quark mass model is also applicable to describing the transition in the supernova core.展开更多
β decay in the strong magnetic field of the crusts of neutron stars is analysed by an improved method. The reactions ^67Ni（β-）^67Cu and ^62Mn（β-）^62Fe are investigated as examples. The results show that a weak ...β decay in the strong magnetic field of the crusts of neutron stars is analysed by an improved method. The reactions ^67Ni（β-）^67Cu and ^62Mn（β-）^62Fe are investigated as examples. The results show that a weak magnetic field has little effect on β decay but a strong magnetic field （B 〉 10^12G） increases β decay rates obviously. The conclusion derived may be crucial to the research of late evolution of neutron stars and nucleosynthesis in r-process.展开更多
Using the nuclear shell model,we study the influence of ultra-strong magnetic field on the electron capture nuclei reactions 56,58Co→ 56,58Fe,56,57Ni→ 56,57Co,52,53Fe→ 52,53Mn and 57,60Cu→ 57,60Ni.The results show...Using the nuclear shell model,we study the influence of ultra-strong magnetic field on the electron capture nuclei reactions 56,58Co→ 56,58Fe,56,57Ni→ 56,57Co,52,53Fe→ 52,53Mn and 57,60Cu→ 57,60Ni.The results show that the electron capture rates of most iron group nuclei are increased greatly in the ultrastrong magnetic field,and even exceed three orders of magnitude in the range from 5 ×10^(13) G to 2.5 × 10^(17)G.展开更多
By using the new Coulomb screening model and most recent experimental results, this paper calculates the resonance reaction rates of ^21Na（p,γ）^22Mg. The derived result shows that the effect of electron screening o...By using the new Coulomb screening model and most recent experimental results, this paper calculates the resonance reaction rates of ^21Na（p,γ）^22Mg. The derived result shows that the effect of electron screening on resonant reaction is prominent in astrophysical interesting temperature range. In conjunction with the experimental results, the recommended rates of^21Na（p,γ）^22 Mg would increase at least 10%, which undoubtedly affect the nucleosynthesis of some heavier nuclei in a variety of astrophysical sites.展开更多
Improving Salpeter＇s method, we discuss the effect of superstrong magnetic fields （such as those of magnetars） on thermonuclear reaction rates. These most interesting reactions, including the hydrogen burning by th...Improving Salpeter＇s method, we discuss the effect of superstrong magnetic fields （such as those of magnetars） on thermonuclear reaction rates. These most interesting reactions, including the hydrogen burning by the CNO cycle and the helium burning by the triple alpha reaction, are investigated as examples on the magnetar surfaces. The obtained result shows that the superstrong magnetic fields can increase the thermonuclear reaction rates by many orders of magnitude. The enhancement may have significant influence for further study research of the magnetars, especially for the x-ray luminosity observation and the evolution of magnetars.展开更多
The chemical potential of electrons in a strong magnetic field is investigated. It is shown that the magnetic field has only a slight effect on electron chemical potential when B 〈 10^11 T, but electron chemical pote...The chemical potential of electrons in a strong magnetic field is investigated. It is shown that the magnetic field has only a slight effect on electron chemical potential when B 〈 10^11 T, but electron chemical potential will decrease greatly when B 〉 10^11 T. The effects of a strong magnetic field on electron capture rates for ^60Fe are discussed, and the result shows that the electron capture sharply decreases because of the strong magnetic field.展开更多
Based on a new screening Coulomb model, this paper discusses the effect of electron screening on proton capture reaction of 23Mg. The derived result shows that, in some considerable range of stellar temperatures, the ...Based on a new screening Coulomb model, this paper discusses the effect of electron screening on proton capture reaction of 23Mg. The derived result shows that, in some considerable range of stellar temperatures, the effect of electron screening on resonant reaction is prominent; on the non-resonant reaction the effect is obvious only in the low stellar temperatures. The reaction rates of ^23Mg（p,γ） ^24Al would increase 15%-25% due to the fact that the electron screening are considered in typical temperature range of massive mass white dwarfs, and the results undoubtedly affect the nucleosynthesis of some heavier nuclei in massive mass white dwarfs.展开更多
In this paper electron capture on iron group nuclei in crusts of neutron stars in a strong magnetic field is investigated. The results show that the magnetic fields have only a slight effect on electron capture rates ...In this paper electron capture on iron group nuclei in crusts of neutron stars in a strong magnetic field is investigated. The results show that the magnetic fields have only a slight effect on electron capture rates in a range of 10^5 - 10^13g on surfaces of most neutron stars, whereas for some magnetars the magnetic fields range from 10^13 to 10^18 G. The electron capture rates of most iron group nuclei are greatly decreased, reduced by even four orders of magnitude due to the strong magnetic field.展开更多
A new improved nuclear partition function is employed to calculate the nuclear statistical equilibrium （NSE） in core-collapse supernova environment. The results show that the change of nucleus abundance is slight ev...A new improved nuclear partition function is employed to calculate the nuclear statistical equilibrium （NSE） in core-collapse supernova environment. The results show that the change of nucleus abundance is slight even though the temperature is higher than 10^11 K when shock propagates, which indicates that the effect of the nuclear partition function is not so important as shown in the previous calculations, but it can also be considered in detailed simulation if it is sensitive to weak interaction rates in core-collapse supernova.展开更多
The influences on the neutrino energy loss rates in iron group nuclei at the same density are investigated in the presence of strong electron screening and in the absence of electron screening. The results show that a...The influences on the neutrino energy loss rates in iron group nuclei at the same density are investigated in the presence of strong electron screening and in the absence of electron screening. The results show that at a temperature of 15 × 10^9 K, the neutrino energy loss rates which come from the electron capture process for most iron group nuclei decrease no more than 2 orders of magnitude but for the others （such as ^53,55,56,57,58,59,6o Co, ^56,59Ni） they can decrease about 3 orders of magnitude due to strong electron screening （SES）, whereas, at a temperature of 10^9K the neutrino energy loss rates of the most iron group nuclei can be diminished greatly due to the SES. For example, ^61Fe, ^60Fe, and ^62Ni the neutrino energy loss rates decrease about 4, 15 and 16 orders of magnitude and for ^57Cr, ^58Cr, and ^60Cr decrease about 18, 12, and 10 orders of magnitude respectively. According to our calculations the neutrino energy loss rates of nuclei ^58Mn, ^59Mn, ^60Mn, and ^62Mn may decrease about 13 orders of magnitude at a temperature of 10^9 K due to the SES.展开更多
A simple and efficient screening model for studying the effects of superstrong magnetic fields （such as those of magnetars） on thermonuclear reaction rates on magnetar surfaces is proposed in this paper. The most in...A simple and efficient screening model for studying the effects of superstrong magnetic fields （such as those of magnetars） on thermonuclear reaction rates on magnetar surfaces is proposed in this paper. The most interesting thermonuclear reactions, including hydrogen burning by the CNO cycle and helium burning by the triple alpha reaction, are investigated on the surface ofmagnetars. We find that the superstrong magnetic fields can increase the thermonuclear reaction rates by many orders of magnitude. The enhancement may have a dramatic effect on the thermonuclear runaways and bursts on the surfaces of magnetars.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant No 10778719)by Scientific Research and Fund of Sichuan Provincial Education Department of China (Grant Nos 2006A079 and 07BZ090)
文摘Based on the new screening model, this paper discusses the influence of superstrong magnetic fields on nuclear energy generation rates on the surface of magnetars. The obtained result shows that the superstrong magnetic fields can increase the nuclear energy generation rates by many orders of magnitude. The enhancement may have a significant influence for further study of the magnetars, especially for the cooling, the x-ray luminosity observation and the evolution of the magnetars.
基金Project supported by the National Natural Science Foundation of China(Grant No10778719)the Scientific Research and Fund of Sichuan Provincial Education Department of China(Grant No2006A079)the Science and Technological Foundation of China West Normal University
文摘The electron capture timescale may be shorter than hydrodynamic timescale in inner iron core of core-collapse supernova according to a recent new idea. Based on the new idea, this paper carries out a numerical simulation on supernova explosion for the progenitor model Ws15M. The numerical result shows that the size of proto-neutron star has a significant change （decrease about 20%）, which may affects the propagation of the shock wave and the final explosion energy.
基金Project supported by the National Natural Science Foundation of China (Grant No 10778719)
文摘By adjusting the pressure grads in the stage of formation of the shock wave, a successful prompt explosion process has been numerically simulated through a progenitor model of 15Msolar, in which the effects of pressure grads on various convections, including the Rayleigh-Taloy （R-T） convection, the lepton driven convection and the negative entropy grads driven convection, in an inner core are analysed. The simulation results showthat the increase of the pressure grads in the inner core region may cause a powerful convection, which causes energy transfer from the inner core to the shock wave rapidly and efficiently.
基金Project supported by the National Natural Science Foundation of China (Grant No. 10778719)the Scientific Research Funds of Sichuan Provincial Education Department, China (Grant Nos. 2009ZB087 and 10ZC004)the China West Normal University(Grant Nos.11B007 and 11B008)
文摘Previous studies have shown that 33S（p,γ）34Cl is the most important reaction that affects the abundance of 33S in the product of nova nucleosynthesis. In this paper, a more accurate thermonuclear reaction rate of 33S（p, γ）34Cl in the nova is calculated based on the newly measured 34C1 nuclear resonance levels. The electron screening correction and the non-resonance and narrow-resonance contributions are considered. The calculations are also combined with the recent observational data of nova V1065 Centauri and show that the thermonuclear reaction rates of 33S（p, γ） 34C1 are significantly different in the improved method. Because these results can affect the isotopic ratio of sulfur in the nova ejecta significantly, we make an estimate of the values of 328/33S and 338/338Q, which can be used as a diagnostic tool for the novae.
基金Project supported by the National Natural Science Foundation of China (Grant No 10347008)the Scientific Research and Fund of Sichuan Provincial Education Department (Grant No.2006A079)the Science and Technological Foundation of China West Normal University
文摘Constituent quark mass model is adopted as a tentative one to study the phase transition between two-flavour quark matter and more stable three-flavour quark matter in the core of supernovae. The result shows that the transition has a significant influence on the increasing of the core temperature, the neutrino abundance and the neutrino energies, which contributes to the enhancement of the successful probability of supernova explosion. However, the equilibrium values of these parameters （except the temperature） from the constituent quark mass model in this work are slightly bigger than those obtained from the other model. And we find that the constituent quark mass model is also applicable to describing the transition in the supernova core.
基金Project suoported by the National Natural Science Foundation of China （Grant No 10347008）.
文摘β decay in the strong magnetic field of the crusts of neutron stars is analysed by an improved method. The reactions ^67Ni（β-）^67Cu and ^62Mn（β-）^62Fe are investigated as examples. The results show that a weak magnetic field has little effect on β decay but a strong magnetic field （B 〉 10^12G） increases β decay rates obviously. The conclusion derived may be crucial to the research of late evolution of neutron stars and nucleosynthesis in r-process.
基金Supported by the National Natural Science Foundation of China under Grant No 10778719.
文摘Using the nuclear shell model,we study the influence of ultra-strong magnetic field on the electron capture nuclei reactions 56,58Co→ 56,58Fe,56,57Ni→ 56,57Co,52,53Fe→ 52,53Mn and 57,60Cu→ 57,60Ni.The results show that the electron capture rates of most iron group nuclei are increased greatly in the ultrastrong magnetic field,and even exceed three orders of magnitude in the range from 5 ×10^(13) G to 2.5 × 10^(17)G.
基金Project supported by the National Natural Science Foundation of China （Grant No 10347008）, the Scientific Research and Fund of Sichuan Provincial Education Department of China （Grant No 2006A079） and the Science and Technological Foundation of China West Normal University.
文摘By using the new Coulomb screening model and most recent experimental results, this paper calculates the resonance reaction rates of ^21Na（p,γ）^22Mg. The derived result shows that the effect of electron screening on resonant reaction is prominent in astrophysical interesting temperature range. In conjunction with the experimental results, the recommended rates of^21Na（p,γ）^22 Mg would increase at least 10%, which undoubtedly affect the nucleosynthesis of some heavier nuclei in a variety of astrophysical sites.
基金Supported by the National Natural Science Foundation of China under Grant No 10778719, and the Scientific Research and Fund of Sichuan Provincial Education Department under Grant Nos 2006A079 and 07BZ090.
文摘Improving Salpeter＇s method, we discuss the effect of superstrong magnetic fields （such as those of magnetars） on thermonuclear reaction rates. These most interesting reactions, including the hydrogen burning by the CNO cycle and the helium burning by the triple alpha reaction, are investigated as examples on the magnetar surfaces. The obtained result shows that the superstrong magnetic fields can increase the thermonuclear reaction rates by many orders of magnitude. The enhancement may have significant influence for further study research of the magnetars, especially for the x-ray luminosity observation and the evolution of magnetars.
基金supported by the National Natural Science Foundation of China (Grant No.10778719)
文摘The chemical potential of electrons in a strong magnetic field is investigated. It is shown that the magnetic field has only a slight effect on electron chemical potential when B 〈 10^11 T, but electron chemical potential will decrease greatly when B 〉 10^11 T. The effects of a strong magnetic field on electron capture rates for ^60Fe are discussed, and the result shows that the electron capture sharply decreases because of the strong magnetic field.
基金Project supported by the National Natural Science Foundation of China （Grant No 10347008）.
文摘Based on a new screening Coulomb model, this paper discusses the effect of electron screening on proton capture reaction of 23Mg. The derived result shows that, in some considerable range of stellar temperatures, the effect of electron screening on resonant reaction is prominent; on the non-resonant reaction the effect is obvious only in the low stellar temperatures. The reaction rates of ^23Mg（p,γ） ^24Al would increase 15%-25% due to the fact that the electron screening are considered in typical temperature range of massive mass white dwarfs, and the results undoubtedly affect the nucleosynthesis of some heavier nuclei in massive mass white dwarfs.
基金Project supported by the National Natural Science Foundation of China （Grant No 10347008）.
文摘In this paper electron capture on iron group nuclei in crusts of neutron stars in a strong magnetic field is investigated. The results show that the magnetic fields have only a slight effect on electron capture rates in a range of 10^5 - 10^13g on surfaces of most neutron stars, whereas for some magnetars the magnetic fields range from 10^13 to 10^18 G. The electron capture rates of most iron group nuclei are greatly decreased, reduced by even four orders of magnitude due to the strong magnetic field.
基金Project supported by the National Natural Science Foundation of China （Grant No 10347008）.
文摘A new improved nuclear partition function is employed to calculate the nuclear statistical equilibrium （NSE） in core-collapse supernova environment. The results show that the change of nucleus abundance is slight even though the temperature is higher than 10^11 K when shock propagates, which indicates that the effect of the nuclear partition function is not so important as shown in the previous calculations, but it can also be considered in detailed simulation if it is sensitive to weak interaction rates in core-collapse supernova.
基金Project supported by the National Natural Science Foundation of China （Grant No 10347008）.
文摘The influences on the neutrino energy loss rates in iron group nuclei at the same density are investigated in the presence of strong electron screening and in the absence of electron screening. The results show that at a temperature of 15 × 10^9 K, the neutrino energy loss rates which come from the electron capture process for most iron group nuclei decrease no more than 2 orders of magnitude but for the others （such as ^53,55,56,57,58,59,6o Co, ^56,59Ni） they can decrease about 3 orders of magnitude due to strong electron screening （SES）, whereas, at a temperature of 10^9K the neutrino energy loss rates of the most iron group nuclei can be diminished greatly due to the SES. For example, ^61Fe, ^60Fe, and ^62Ni the neutrino energy loss rates decrease about 4, 15 and 16 orders of magnitude and for ^57Cr, ^58Cr, and ^60Cr decrease about 18, 12, and 10 orders of magnitude respectively. According to our calculations the neutrino energy loss rates of nuclei ^58Mn, ^59Mn, ^60Mn, and ^62Mn may decrease about 13 orders of magnitude at a temperature of 10^9 K due to the SES.
基金Project supported by the National Natural Science Foundation of China (Grant No 10778719)the Scientific Research and Fund of Sichuan Provincial Education Department, China (Grant No 2006A079)the Science and Technological Foundation of China West Normal University, China
文摘A simple and efficient screening model for studying the effects of superstrong magnetic fields （such as those of magnetars） on thermonuclear reaction rates on magnetar surfaces is proposed in this paper. The most interesting thermonuclear reactions, including hydrogen burning by the CNO cycle and helium burning by the triple alpha reaction, are investigated on the surface ofmagnetars. We find that the superstrong magnetic fields can increase the thermonuclear reaction rates by many orders of magnitude. The enhancement may have a dramatic effect on the thermonuclear runaways and bursts on the surfaces of magnetars.
