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Study of primordial deuterium abundance in Big Bang nucleosynthesis

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Nuclear Science and Techniques 2024年第3期35卷 208-215页

作者： Zhi-Lin Shen Jian-Jun He Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China

Big Bang nucleosynthesis(BBN)theory predicts the primordial abundances of the light elements^(2) H(referred to as deuterium,or D for short),^(3)He,^(4)He,and^(7) Li produced in the early *** these,deuterium,the first nuclide produced by BBN,is a key primordial material for subsequent *** date,the uncertainty in predicted deuterium abundance(D/H)remains larger than the observational *** this study,the Monte Carlo simulation code PRIMAT was used to investigate the sensitivity of 11 important BBN reactions to deuterium *** found that the reaction rate uncertainties of the four reactions d(d,n)^(3)He,d(d,p)t,d(p,γ)^(3)He,and p(n,γ)d had the largest influence on the calculated D/H ***,the calculated D/H uncertainty cannot reach observational precision even with the recent LUNA precise d(p,γ)^(3) He *** the nuclear physics aspect,there is still room to largely reduce the reaction-rate uncertainties;hence,further measurements of the important reactions involved in BBN are still necessary.A photodisintegration experiment will be conducted at the Shanghai Laser Electron Gamma Source Facility to precisely study the deuterium production reaction of p(n,γ)d.

关键词： Big Bang nucleosynthesis Abundance of deuterium reaction cross section reaction rate Monte Carlo method

Direct measurement of the break-out ^(19)F(p,γ)^(20)Ne reaction in the China Jinping underground laboratory(CJPL)

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Nuclear Science and Techniques 2024年第8期35卷 142-152页

作者： Yin‑Ji Chen Hao Zhang Li‑Yong Zhang Jian‑Jun He Richard James deBoer Michael Wiescher Alexander Heger David Kahl Jun Su Daniel Odell Xin‑Yue Li Jian‑Guo Wang Long Zhang Fu‑Qiang Cao Zhi‑Cheng Zhang Xin‑Zhi Jiang Luo‑Huan Wang Zi‑Ming Li Lu‑Yang Song Liang‑Ting Sun Qi Wu Jia‑Qing Li Bao‑Qun Cui Li‑Hua Chen Rui‑Gang Ma Er‑Tao Li Gang Lian Yao‑De Sheng Zhi‑Hong Li Bing Guo Wei‑Ping Liu Key Laboratory of Beam Technology of the Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Department of Physics and Astronomy The Joint Institute for Nuclear AstrophysicsUniversity of Notre DameNotre DameIN 46556USA School of Physics and Astronomy Monash UniversityClaytonVIC 3800Australia Facility for Rare Isotope Beams Michigan State UniversityEast LansingMI 48824USA Institute of Nuclear and Particle Physics and Department of Physics and Astronomy Ohio UniversityAthensOH 45701USA Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China China Institute of Atomic Energy Beijing 102413China College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen 518060China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China College of Science Southern University of Science and TechnologyShenzhen 518055China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China Key Laboratory of Nuclear Physics and Ion‑Beam Application(MOE) Institute of Modern PhysicsFudan UniversityShanghai 200433China School of Mathematics and Physics Handan UniversityHandan 056005China

Calcium production and the stellar evolution of first-generation stars remain fascinating mysteries in *** one possible nucleosynthesis scenario,break-out from the hot carbon–nitrogen–oxygen(HCNO)cycle was thought to be the source of the calcium observed in these oldest ***,according to the stellar modeling,a nearly tenfold increase in the thermonuclear rate ratio of the break-out ^(19)F(p,γ)^(20) Ne reaction with respect to the competing ^(19)F(p,α)^(16) O back-processing reaction is required to reproduce the observed calcium *** performed a direct measurement of this break-out reaction at the China Jinping underground *** measurement was performed down to the low-energy limit of E_(c.m.)=186 keV in the center-of-mass *** key resonance was observed at 225.2 keV for the first *** a temperature of approximately 0.1 GK,this new resonance enhanced the thermonuclear ^(19)F(p,γ)^(20) Ne rate by up to a factor of≈7.4,compared with the previously recommended NACRE *** is of particular interest to the study of the evolution of the first stars and implies a stronger breakdown in their“warm”CNO cycle through the ^(19)F(p,γ)^(20) Ne reaction than previously *** break-out resulted in the production of the calcium observed in the oldest stars,enhancing our understanding of the evolution of the first stars.

关键词： Nuclear astrophysics First stars Abundance of calcium reaction cross section reaction rate China Jinping underground laboratory(CJPL) JUNA

利用强子探针研究奇特原子核的点质子分布半径及强子探针效应

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Science Bulletin 2024年第11期69卷 1647-1652页

作者：张寂潮孙保华 Isao Tanihata Rituparna Kanungo Christoph Scheidenberger Satoru Terashima 王枫 Frederic Ameil Joel Atkinson Yassid Ayyad Soumya Bagchi Dolores Cortina-Gil Iris Dillmann Alfredo Estradé Alexey Evdokimov Fabio Farinon Hans Geissel Giulia Guastalla Rudolf Janik Satbir Kaur Ronja Knöbel Jan Kurcewicz Yury Litvinov Michele Marta Magdalena Mostazo Ivan Mukha Chiara Nociforo Hooi Jin Ong Stephane Pietri Andrej Prochazka Branislav Sitar Peter Strmen Maya Takechi Junki Tanaka Jossitt Vargas Helmut Weick John Stuart Winfield School of Physics Beihang UniversityBeijing 100191China Research Center for Nuclear Physics(RCNP) Osaka UniversityOsaka 567-0047Japan Astronomy and Physics Department Saint Mary’s UniversityHalifax B3H 3C3Canada TRIUMF Vancouver V6T 4A3Canada GSI Helmholtzzentrum für Schwerionenforschung Darmstadt D-64291Germany Justus-Liebig University Gießn 35392Germany Helmholtz Research Academy Hesse for FAIR(HFHF) GSI Helmholtz Center for Heavy Ion ResearchGießn 35392Germany Universidad de Santiago de Compostela Santiago de Compostella E-15706Spain Department of Physics Indian Institute of Technology(Indian School of Mines)Dhanbad 826004India Faculty of Mathematics and Physics Comenius UniversityBratislava 84215Slovakia Department of Physics and Atmospheric Science Dalhousie UniversityHalifax B3H 4R2Canada

We report the charge-changing cross sections(σ_(cc))of 24 p-shell nuclides on both hydrogen and carbon at about 900A MeV,of which^(8,9)Li,^(10–12)Be,^(10,14,15)B,^(14,15,17–22)N and^(16)O on hydrogen and^(8,9)Li on carbon are for the first *** from the data set,we found a new and robust relationship between the scaling factor of the Glauber model calculations and the separation energies of the nuclei of interest on both *** allows us to deduce proton radii(R_p)for the first time from the cross sections on *** identical R_p values are deduced from both target data for the neutron-rich carbon isotopes;however,the R_p from the hydrogen target is systematically smaller in the neutron-rich nitrogen *** calls for further experimental and theoretical investigations.

关键词： Exotic nuclei Nuclear size reaction cross section Glauber model Radioactive ion beam

Nuclear matter incompressibility effect on the cross-section of fusion reactions with a weakly bound projectile

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Chinese Physics C 2015年第8期39卷 50-55页

作者： S.A.Seyyedi H.Golnarkar Sciences Faculty Physics Group Payame-Noor University

Fusion reactions with a weakly bound projectile are studied using the double-folding model along with a repulsive interaction modifying term. Using this modified potential, including nuclear matter incompressibility effects, the fusion reaction cross sections and suppression parameters are calculated for 9Be＋209Bi, 208spb, 29Si and 27A1 reactions. The results show that applying these effects at agreement between the calculated and experimental cross sections parameter. energies near the Coulomb barrier improves the and modifies the mean values of the suppression

关键词： fusion reactions equation of state of nuclear matter reaction cross section

Cosmic implications of the 12C(n, γ)13C reaction: a nuclear astrophysical perspective

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Chinese Physics C 2024年第2期48卷 171-174页

作者： Soumya Saha Department of Physics Bidhan Chandra CollegeRishra31G.T.Road(East)Hooghly-712248India Department of Physics University of Calcutta92Acharya Prafulla Chandra RoadKolkata-700009India

We conducted a comprehensive study of the neutron capture cross section of 12C within the relevant astrophysical energy *** rigorous R-matrix analysis,we determined the Maxwellian-averaged cross section to be 11.98±0.25μb at kT=30 *** result is approximately four times higher than the thermal neutron capture cross section estimated in earlier studies assuming the 1/v *** implications of our findings extend to the region of inhomogeneous Big-Bang models in nuclear astrophysics,where understanding the behaviour of neutron capture cross sections plays a crucial role in elucidating the intricate processes that shaped the early universe.

关键词： reaction cross section R-matrix reaction rates spectroscopic factors

Study of the deformed halo nucleus^(31)Ne with Glauber model based on microscopic self-consistent structures

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Science China(Physics,Mechanics & Astronomy) 2022年第6期65卷 67-75页

作者： Shi-Yi Zhong Shi-Sheng Zhang Xiang-Xiang Sun Michael S.Smith School of Physics Beihang UniversityBeijing 100191China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China Physics Division Oak Ridge National LaboratoryOak Ridge 378^(31)-6354USA

The exotic deformed nucleus^(31)Ne is studied with an approach that combines self-consistent structure and reaction *** deformed relativistic Hartree-Bogoliubov theory in continuum(DRHBc)is utilized to demonstrate that deformation and pairing correlations give rise to a halo structure with a large-amplitude p-wave configuration in^(31)*** the valence nucleon wave functions and angle-averaged density distributions of ^(30)Ne from this theory are used as input for the Glauber reaction model to study the observables of neutron-rich neon isotopes to search halo *** NL1 effective interaction,our predictions of the reaction cross sections for these exotic neon isotopes on a carbon target can better reproduce the experimental data than those from the relativistic mean field model for a spherical shape with resonances and pairing correlation contributions,and are roughly 3.3%(∼50 mb)larger than those with Gaussian function-fitted densities of the core *** calculated one-neutron removal cross section at 240 MeV/nucleon,and the inclusive longitudinal momentum distribution of the 30Ne residues from the^(31)Ne breakup reaction are largely improved over previous theoretical predictions and agree well with *** reaction evalu-ations indicate a dilute density distribution in coordinate space and are a canonical signature of a halo ***,our predictions with the NL3 and PK1 effective interactions give slightly better descriptions of reaction observables for exotic neon isotopes.

关键词： halo relativistic model Glauber model reaction cross section momentum distribution

Global optical model potential describing 12C-nucleus elastic scattering

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Chinese Physics C 2020年第12期44卷 123-132页

作者： Yong-Li Xu Yin-Lu Han Xin-Wu Su Xiao-Jun Sun Hai-Ying Liang Hai-Rui Guo Chong-Hai Cai College of Physics and Electronic Science Shanxi Datong UniversityDatong 037009China Key Laboratory of Nuclear Data China Institute of Atomic EnergyP.O.BOX(275-41)Beijing 102413China College of Physics Guangxi Normal UniversityGuilin 541004China Institute of Applied Physics and Computational Mathematics Beijing 100094China Department of Physics Nankai UniversityTianjin 300071China

We construct a new global optical model potential to describe the elastic scattering of *** experimental data of elastic-scattering angular distributions and total reaction cross sections for targets from 24Mg to 209Bi are considered below 200 MeV within the framework of the optical *** results calculated using the derived global optical potential are then compared with the existing experimental *** reliability of the global optical potential is further tested by predicting the elastic scattering data out of the mass and energy ranges,within which the global potential parameters are determined,and reasonable results are also obtained.

关键词： optical model potential elastic-scattering angular distribution reaction cross section

A theoretical study of the stereodynamics on the abstraction reactions H/D+HS/DS

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Chinese Physics B 2013年第6期22卷 608-614页

作者：徐国亮刘培刘彦磊刘玉芳袁伟张现周 College of Physics & Electronic Engineering Henan Normal University

The quasi-classical trajectory （QCT） method is employed to calculate the stereodynamics of the abstraction reactions H/D ＋ HS/DS based on an accurate potential energy surface [Lti S J, Zhang P Y, Han K L and He G Z 2012 J. Chem. Phys. 136 094308]. The reaction cross sections of the title reaction are computed, and the vector correlations for different collision energies and different initial vibrational states are presented. The influences of the collision energy and reagent vibration on the product polarization are studied, and the product polarizations of the title reactions are found to be distinctly different, which arises from the different mass factors, collision energies, and reagent vibrational states.

关键词： quasi-classical trajectory stereodynamics reaction cross section vector correlation

Description of elastic scattering induced by the unstable nuclei^(9,10,11,13,14)C

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Chinese Physics C 2021年第11期45卷 122-127页

作者： Yong-Li Xu Yin-Lu Han Xin-Wu Su Xiao-Jun Sun Hai-Ying Liang Hai-Rui Guo Chong-Hai Cai College of Physics and Electronic Science Shanxi Datong UniversityDatong 037009China Key Laboratory of Nuclear Data China Institute of Atomic EnergyP.O.BOX(275-41)Beijing 102413China College of Physics Guangxi Normal UniversityGuilin 541004China Guangxi Key Laboratory of Nuclear Physics and Nuclear Technology Guangxi Normal UniversityGuilin 541004China Institute of Applied Physics and Computational Mathematics Beijing 100094China Department of Physics Nankai UniversityTianjin 300071China

The elastic-scattering angular distributions and total reaction cross sections of ^(9,10,11,13,14)C projectiles were predicted using the obtained ^(12)C and ^(9)Be global optical model potentials,*** predictions were analyzed in detail by comparison with the available experimental *** results indicate that the ^(12)C and ^(9)Be global optical model potentials provide a satisfactory description of the elastic scattering data for the reactions induced by the ^(9,10,11,13)*** the neutron-rich carbon isotope ^(14)C,the elastic scattering can be well described by changing the real part radius parameter of the ^(12)C global optical model *** physical explanations for the observed differences are further discussed.

关键词： optical model potential elastic-scattering angular distribution reaction cross section