用于深地核天体物理实验的无窗气体靶差分结构和热效应研究  

Study on Differential Structure and Thermal Effects of Windowless Gas Target for Deep-underground Nuclear Astrophysical Experiments

作　　者：蒋宇辰 连钢[1] 方晓 李云居[1] 曹富强 南巍 曾晟[1] 谌阳平 柳卫平[1,3] JIANG Yuchen;LIAN Gang;FANG Xiao;LI Yunju;CAO Fuqiang;NAN Wei;ZENG Sheng;SHEN Yangping;LIU Weiping(China Institute of Atomic Energy,Beijing 102413,China;Sino-French Institute of Nuclear Engineering and Technology,Sun Yat-sen University,Zhuhai 519082,China;Southern University of Science and Technology,Shenzhen 518055,China)

机构地区：[1]中国原子能科学研究院,北京102413 [2]中山大学中法核工程与技术学院,广东珠海519082 [3]南方科技大学,广东深圳518055

出　　处：《原子能科学技术》2024年第S01期1-8,共8页Atomic Energy Science and Technology

基　　金：国家自然科学基金(11875329);中核集团“青年英才”项目。

摘　　要：我国锦屏深地核天体物理(JUNA)平台是世界上束流强度最高的深地实验平台,为我国争取核天体物理国际领先地位提供了重要机遇。无窗气体靶是深地低能核天体物理实验测量的关键设备,可实现特定同位素参与核反应的直接测量,能有效拓展深地实验的研究范围。国际上已有多家实验室将无窗气体靶应用于低能核反应的研究,但针对的都是较低流强的实验。为适应锦屏高功率强束流的实验需求,本工作设计可用于强流束的气体靶装置。通过Ansys Fluent和COMSOL软件模拟计算,验证了多级差分结构的可行性,并研究了靶厚的束流加热效应和量热器热效应,提出了无窗气体靶实验的设计优化方案,为后续JUNA深地实验研究的发展提供了可靠依据。The JUNA(Jinping Underground Nuclear Astrophysics)platform has the facility with the world’s most intense beams,and provides a crucial opportunity for China to strive for a leading international position in nuclear astrophysics.The first phase of JUNA’s experiments has demonstrated a promising prospect for accurately measuring nuclear astrophysical reactions in underground laboratories.The windowless gas target is a critical component for directly measuring low-energy nuclear astrophysical reactions involving specific isotopes,thereby effectively expanding the scope of deep-underground experiments.Windowless gas targets have been employed in studies of low-energy nuclear reactions in several international laboratories.Represented by the work of Gran Sasso group from Italy,many achievements have been made in nuclear astrophysics research on windowless gas target equipment,including those on Big Bang nucleosynthesis and solar neutrino physics.However,these studies have focused on experiments with relatively low beam intensities.To meet the highpower,high-intensity beam requirements of the JUNA experiment,a dedicated gas target design is needed.In this work,a gas target device that can be used for high intensity beams was designed.Through modeling with ANSYS Fluent and COMSOL software,the feasibility of a multi-stage differential structure was validated.According to the simulation results,it is possible to achieve a total gradient decrease of about 6 orders of magnitude in gas pressure from the target chamber to the accelerator end.This indicates that the current gas target setup is sufficient for our future nuclear reaction measurement experiments.In addition,the heating effect proves to be important for gas target experiment.On one hand,when the beam passes through the gas target,some energy will be deposited,then the target density(i.e.target thickness)near the beam will correspondingly decrease.In nuclear physics experiments,precise measurement of target thickness is an important step in extracting key physi

关 键 词：核天体物理 深地实验室 无窗气体靶 低能核反应 

分 类 号：TL8[核科学技术—核技术及应用]