The astrophysical reaction rate of the charged-particleinduced reaction is dominated by the cross section within the Gamow window.The total cross section σ(E)of a chargedparticle-induced reaction is known to drops st...The astrophysical reaction rate of the charged-particleinduced reaction is dominated by the cross section within the Gamow window.The total cross section σ(E)of a chargedparticle-induced reaction is known to drops steeply with decreasing energy owing to the Coulomb barrier in the entrance channel:展开更多
Jinping Underground laboratory for Nuclear Astrophysics(JUNA) will take the advantage of the ultra-low background of CJPL lab and high current accelerator based on an ECR source and a highly sensitive detector to dire...Jinping Underground laboratory for Nuclear Astrophysics(JUNA) will take the advantage of the ultra-low background of CJPL lab and high current accelerator based on an ECR source and a highly sensitive detector to directly study for the first time a number of crucial reactions occurring at their relevant stellar energies during the evolution of hydrostatic stars. In its first phase, JUNA aims at the direct measurements of^(25)Mg(p,γ)^(26)Al,^(19)F(p,α)^(16)O,^(13)C(α,n)^(16)O and ^(12)C(α,γ)^(16)O reactions. The experimental setup,which includes an accelerator system with high stability and high intensity, a detector system, and a shielding material with low background, will be established during the above research. The current progress of JUNA will be given.展开更多
In 2014, the National Natural Science Foundation of China(NSFC) approved the Jinping Underground Nuclear Astrophysics laboratory(JUNA) project, which aims at direct cross-section measurements of four key stellar nucle...In 2014, the National Natural Science Foundation of China(NSFC) approved the Jinping Underground Nuclear Astrophysics laboratory(JUNA) project, which aims at direct cross-section measurements of four key stellar nuclear reactions right down to the Gamow windows. In order to solve the observed fluorine overabundances in Asymptotic Giant Branch(AGB) stars, measuring the key ^(19)F( p,α)^(16)O reaction at effective burning energies(i.e., at Gamow window) is established as one of the scientific research sub-projects. The present paper describes this sub-project in details, including motivation, status, experimental setup, yield and background estimation, aboveground test, as well as other relevant reactions.展开更多
Several elastic scattering angular distributions of ^(12)C from target nuclei of A ≥39 are analyzed to extract the Woods-Saxon potential parameters with the fixed imaginary potential and Coulomb radius parameters.Usi...Several elastic scattering angular distributions of ^(12)C from target nuclei of A ≥39 are analyzed to extract the Woods-Saxon potential parameters with the fixed imaginary potential and Coulomb radius parameters.Using the best fitted diffuseness parameters,the correlations of the real part parameters with A_1^(1/3)+ A_2^(1/3) and incident energy are revealed, and the systematic Woods-Saxon potential parameters are presented for nucleus-nucleus interaction.The proposed potential parameters can reproduce not only the elastic scattering angular distributions induced by ^(12)C,but also many elastic scattering angular distributions induced by the projectiles other than ^(12)C,thus providing important inputs for the study of nuclear reactions of heavy-ion systems.展开更多
Experimental data ofβ--decay half-lives of nuclei with atomic number between 20 and 190 are investigated.A systematic formula has been proposed to calculateβ^--decay half-lives of neutron-rich nuclei,with a particul...Experimental data ofβ--decay half-lives of nuclei with atomic number between 20 and 190 are investigated.A systematic formula has been proposed to calculateβ^--decay half-lives of neutron-rich nuclei,with a particular consideration on shell and pair effects,the decay energy Q as well as the nucleon numbers(Z,N).Although the formula has relatively few parameters,it reproduces the experimentalβ^--decay half-lives of neutron-rich nuclei very well.The predicted half-lives for the r-process relevant nuclei obtained with the current formula serve as reliable input in the r-process model calculations.展开更多
The14C(n,γ)15C reaction plays an important role in various astrophysical scenarios:(1)it is the slowest in the neutron induced CNO cycle which occurs in asymptotic giant branch(AGB)stars,and therefore controls this c...The14C(n,γ)15C reaction plays an important role in various astrophysical scenarios:(1)it is the slowest in the neutron induced CNO cycle which occurs in asymptotic giant branch(AGB)stars,and therefore controls this cycle[1];(2)it is one of the key reactions for predicting the primordial abundances of the heavy elements in the framework of inhomogeneous big-bang nucleosynthesis(IBBN)[2];(3)it is also important for the synthesis of heavier isotopes in neutrino driven wind scenarios for the r-process in core-collapse supernova(i.e.,Type-II supernova)explosions[3-5].展开更多
基金supported by the National Natural Science Foundation of China(1149056312125509U18672111196114100311775133and 12175152)the Continuous Basic Scientific Research Project No.WDJC-2019-13+1 种基金the Equipment Research and Development Project of Chinese Academy of Sciences(28Y531040)research fund of CNNC。
基金the National Natural Science Foundation of China(Grant Nos.11490560,and 11321064)the National Basic Research Program of China(Grant No.2013CB834406)
文摘The astrophysical reaction rate of the charged-particleinduced reaction is dominated by the cross section within the Gamow window.The total cross section σ(E)of a chargedparticle-induced reaction is known to drops steeply with decreasing energy owing to the Coulomb barrier in the entrance channel:
基金supported by the National Natural Science Foundation of China(Grant Nos.11490560 and 11321064)the National Basic Research Program of China(Grant No.2013CB834406)
文摘Jinping Underground laboratory for Nuclear Astrophysics(JUNA) will take the advantage of the ultra-low background of CJPL lab and high current accelerator based on an ECR source and a highly sensitive detector to directly study for the first time a number of crucial reactions occurring at their relevant stellar energies during the evolution of hydrostatic stars. In its first phase, JUNA aims at the direct measurements of^(25)Mg(p,γ)^(26)Al,^(19)F(p,α)^(16)O,^(13)C(α,n)^(16)O and ^(12)C(α,γ)^(16)O reactions. The experimental setup,which includes an accelerator system with high stability and high intensity, a detector system, and a shielding material with low background, will be established during the above research. The current progress of JUNA will be given.
基金supported by the National Natural Science Foundation of China(Grant Nos.114905621149056011135005 and 11321064)
文摘In 2014, the National Natural Science Foundation of China(NSFC) approved the Jinping Underground Nuclear Astrophysics laboratory(JUNA) project, which aims at direct cross-section measurements of four key stellar nuclear reactions right down to the Gamow windows. In order to solve the observed fluorine overabundances in Asymptotic Giant Branch(AGB) stars, measuring the key ^(19)F( p,α)^(16)O reaction at effective burning energies(i.e., at Gamow window) is established as one of the scientific research sub-projects. The present paper describes this sub-project in details, including motivation, status, experimental setup, yield and background estimation, aboveground test, as well as other relevant reactions.
基金supported by the National Natural Science Foundation of China(Grant Nos.11375269,and 11490560)the National Basic Research Program of China(Grant No.2013CB834406)the National Key Research and Development Program of China(Grant No.2016YFA0400502)
文摘Several elastic scattering angular distributions of ^(12)C from target nuclei of A ≥39 are analyzed to extract the Woods-Saxon potential parameters with the fixed imaginary potential and Coulomb radius parameters.Using the best fitted diffuseness parameters,the correlations of the real part parameters with A_1^(1/3)+ A_2^(1/3) and incident energy are revealed, and the systematic Woods-Saxon potential parameters are presented for nucleus-nucleus interaction.The proposed potential parameters can reproduce not only the elastic scattering angular distributions induced by ^(12)C,but also many elastic scattering angular distributions induced by the projectiles other than ^(12)C,thus providing important inputs for the study of nuclear reactions of heavy-ion systems.
基金supported by the National Natural Science Foundation of China(Grant Nos.11490563 and 11375269)the National Basic Research Program of China(Grant No.2013CB834406)the National Key Research and Development Program of China(Grant No.2016YFA0400502)
文摘Experimental data ofβ--decay half-lives of nuclei with atomic number between 20 and 190 are investigated.A systematic formula has been proposed to calculateβ^--decay half-lives of neutron-rich nuclei,with a particular consideration on shell and pair effects,the decay energy Q as well as the nucleon numbers(Z,N).Although the formula has relatively few parameters,it reproduces the experimentalβ^--decay half-lives of neutron-rich nuclei very well.The predicted half-lives for the r-process relevant nuclei obtained with the current formula serve as reliable input in the r-process model calculations.
基金supported by the National Key Research and Development Project(Grant No.2016YFA0400502)the National Natural Science Foundation of China(Grant Nos.11490561,11475264,11475265,and11575292)the National Program on Key Basic Research Project of China(Grant No.2013CB834406)
文摘The14C(n,γ)15C reaction plays an important role in various astrophysical scenarios:(1)it is the slowest in the neutron induced CNO cycle which occurs in asymptotic giant branch(AGB)stars,and therefore controls this cycle[1];(2)it is one of the key reactions for predicting the primordial abundances of the heavy elements in the framework of inhomogeneous big-bang nucleosynthesis(IBBN)[2];(3)it is also important for the synthesis of heavier isotopes in neutrino driven wind scenarios for the r-process in core-collapse supernova(i.e.,Type-II supernova)explosions[3-5].