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Constraints on symmetry energy and n/p effective mass splitting with improved quantum molecular dynamics model 被引量:1
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作者 ZHANG Yingxun LI Zhuxia +2 位作者 ZHAO Kai LIU Hang TSANG M B 《Nuclear Science and Techniques》 SCIE CAS CSCD 2013年第5期13-18,共6页
A new version of improved quantum molecular dynamics model that includes standard Skyrme interactions has been developed.Based on the new code,four commonly used parameter sets,SLy4,SkI2,SkM*and Gs are adopted in the ... A new version of improved quantum molecular dynamics model that includes standard Skyrme interactions has been developed.Based on the new code,four commonly used parameter sets,SLy4,SkI2,SkM*and Gs are adopted in the improved quantum molecular dynamics model and the isospin sensitive observables,namely isospin transport ratios,single and double ratios of the yields of neutrons and protons are investigated.The isospin transport ratios are strongly sensitive to the slope of symmetry energy,and are not very sensitive to the nucleon effective mass splitting.On the other hand,the high energy neutrons and protons yields ratios from reactions at different incident energies provide a good observable to the momentum dependence of nucleon effective mass splitting.By comparing our calculations with the data,we find that the constrained L value(the slope of density dependence of symmetry energy) is about ~46 MeV when the Skyrme type interaction is considered in transport models,and the isospin diffusion data prefer to mn*>mp*,but it is not a strong constraint with deep χ2minimum. 展开更多
关键词 量子分子动力学模型 核子有效质量 对称能 Skyrme相互作用 分裂 密度依赖性 入射能量 运输模型
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Three-dimensional electric field calculations for wire chamber using element refinement method in ANSYS
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作者 Yao-Feng Zhang J. Barney +1 位作者 M. B. Tsang Chun-Lei Zhang 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第12期96-101,共6页
Finite element analysis(FEA) method was employed to perform three-dimensional(3D) electric field simulations for gas detectors with multiple wire electrodes.A new element refinement method developed for use in conjunc... Finite element analysis(FEA) method was employed to perform three-dimensional(3D) electric field simulations for gas detectors with multiple wire electrodes.A new element refinement method developed for use in conjunction with the FEA program ANSYS allows successful meshing of the wires without physically inputting the wires in the chamber geometry. First, we demonstrate a model with only one wire, for which we calculate the potential distributions on the central plane and the end-cap region. The results are compared to the calculations obtained using GARFIELD, a two-dimensional program that uses the nearly exact boundary element method. Then we extend the method to same model, but with seven wires.Our results suggest that the new method can be applied easily to the 3D electric field calculations for complicated gas detectors with many wires and complicated geometry such as multiwire proportional chambers and time projection chambers. 展开更多
关键词 有限元素分析 ANSYS 电场计算 精炼方法 电线 房间 三维 电场模拟
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Proton Spectroscopic Factors Deduced from Helium-3 Global Phenomenological and Microscopic Optical Model Potentials 被引量:1
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作者 李晓菁 庞丹阳 +1 位作者 韩银录 曾敏儿 《Chinese Physics Letters》 SCIE CAS CSCD 2014年第9期36-39,共4页
Global phenomenological GDP08 and microscopic hefium-3 optical model potentials have been recently derived. We evaluate these two potential sets by comparing the elastic scattering data of 25 MeV 3He on 160, 180, 19F,... Global phenomenological GDP08 and microscopic hefium-3 optical model potentials have been recently derived. We evaluate these two potential sets by comparing the elastic scattering data of 25 MeV 3He on 160, 180, 19F, 23Na, 24Mg, 25Mg, 26Mg, 27A1, 28Si, 30Si, 31p, 32S, 34S, 35Cl, 3761, and 39K isotopes. Using the deuteron angular distributions calculated with the distorted wave Born approximation model, we extract the ground-state proton spectroscopic factors from (3He, d) reactions on the same set of nuclei. The extracted proton spectroscopic factors are compared with the large-basis shell-model calculations. 展开更多
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Nitrogen Desorption and Positron Sensitive Defect of CVD Diamond
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作者 Kasey R. Lund Kelvin G. Lynn +2 位作者 Marc H. Weber Chao Liu Elgin Eissler 《Journal of Modern Physics》 2017年第5期770-785,共16页
The chemical vapor deposition (CVD) process can produce single or poly-crystalline diamond samples of high purity or with controlled doping concentrations. The defect type in the CVD diamonds can be changed by heating... The chemical vapor deposition (CVD) process can produce single or poly-crystalline diamond samples of high purity or with controlled doping concentrations. The defect type in the CVD diamonds can be changed by heating the samples. Controlling the defect type can be used to create devices for quantum diamond switches that could be used in radiation sensors and quantum information technology. Eight samples of CVD diamonds were analyzed with Doppler broadening of positron annihilation radiation (DBAR) before and after annealing in high vacuum with an electron gun. Between temperatures of 1700 - 1850 K, nitrogen was liberated from the diamond sample. At these high temperatures, the surface was graphitized and a change in the color and transparency of the diamond was observed. Some of the samples were analyzed with DBAR during periods with and without light. The defect properties were observed to change depending on the time exposure to the positron beam and were then regenerated by exposure to light. The DBAR data is compared to photoluminescence data and a time varying defect state is discussed for detector and optical grade type II CVD diamonds. 展开更多
关键词 CVD DIAMOND Detectors POSITRON ANNIHILATION Spectroscopy DIVACANCY
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Beam Dynamics Studies of ECR Injections for the Coupled Cyclotron Facility at NSCL
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作者 D.Cole M.Doleans +4 位作者 G.Machicoane F.Marti P.Miller J.Stetson M.Steiner P.Zavodszky 《Chinese Physics C》 SCIE CAS CSCD 北大核心 2007年第S1期196-200,共5页
The Coupled Cyclotron Facility (CCF) has been operating at the NSCL since 2001,providing up to 160MeV/u heavy ion beams for nuclear physics experiments.Recent steps,particularly the improvement of the ECR-to-K500 inje... The Coupled Cyclotron Facility (CCF) has been operating at the NSCL since 2001,providing up to 160MeV/u heavy ion beams for nuclear physics experiments.Recent steps,particularly the improvement of the ECR-to-K500 injection line,were taken to improve the CCF performance.For that purpose an off-line ECR source,ARTEMIS-B,was built and used to investigate the impact on beam brightness under various source operating conditions,different initial focusing systems and current analysis dipole.Beam dynamics simulations including space-charge and 3D electrostatic field effects were performed and beam diagnostics including emittance scanner were used,leading to a better understanding of the CCF beam injection process. New initial electrostatic focusing elements such as a large-bore quadrupole triplet and a quadrupole double- doublet with compensating octupole were tested,and a new beam tuning procedure was established to improve the beam brightness for the CCF.Following these efforts,a significant increase of primary beam power out of the CCF has been achieved. 展开更多
关键词 ECR injection ELECTROSTATIC QUADRUPOLE FOCUSING analysis DIPOLE
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Status Report of the NSCL/MSU ECR Ion Sources
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作者 P.A.Závodszky B.Mend +11 位作者 D.Cole J.DeKamp M.Doleans G.Machicoane F.Marti P.Miller J.Moskalik W.Nurnberger J.Ottarson M.Steiner J.Stetson J.Vincent A.Zeller 《Chinese Physics C》 SCIE CAS CSCD 北大核心 2007年第S1期18-22,共5页
Since the last ECR Workshop,NSCL/MSU has been involved in a vigorous ECR ion source R&D program,which resulted in the construction of an off-line test ECR ion source(ARTEMIS-B)for new beam development and ion opti... Since the last ECR Workshop,NSCL/MSU has been involved in a vigorous ECR ion source R&D program,which resulted in the construction of an off-line test ECR ion source(ARTEMIS-B)for new beam development and ion optics studies.Also the design and partial completion of a 3rd generation,fully supercon- ducting ECR ion source,SuSI has been accomplished.This paper is an overview of the construction projects and the different R&D activities performed with the existing ion sources.These activities include development of metallic ion beam production methods using evaporation with resistive and inductive ovens and sputtering of very refractory metals.Ion optics developments include testing different focusing elements(magnetic solenoid lens,electrostatic quadrupole triplet lens,Einzel lens,electrostatic double doublet quadrupole combined with an octupole lens),and different beam forming and diagnostics devices.The detailed results will be presented at the workshop in separate talks and posters. 展开更多
关键词 ECR ion SOURCES highly CHARGED IONS beam OPTICS
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R&D Effort at NSCL with the Off-line ECR Ion Source ARTEMIS-B
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作者 G.Machicoane M.Doleans +4 位作者 G.Humenik F.Marti P.Miller M.Steiner J.Stetson P.Zavodszky 《Chinese Physics C》 SCIE CAS CSCD 北大核心 2007年第S1期187-191,共5页
This paper reviews recent experimental work done with the off line source ARTEMIS-B at the NSCL.This source was built during the year 2005 and provides opportunities for off line development that can benefit the Coupl... This paper reviews recent experimental work done with the off line source ARTEMIS-B at the NSCL.This source was built during the year 2005 and provides opportunities for off line development that can benefit the Coupled Cyclotron Facility(CCF)operation while minimizing the time taken away from the nuclear experimental program.The Artemis-B setup includes many beam diagnostics and a detailed description of the emittance scanner(Allison)and emittance measurement method is presented.A first beam dynamics study indicates that the analysis magnet has strong field aberrations and that the beam size in the dipole must be small in order to avoid significant beam brightness degradation.A second study compares beam brightness for different focusing systems between the ECR ion source and the analyzing magnet.Two electrostatic devices:a quadrupole triplet and a double quadrupole doublet have been tested successively and compared to a magnetic focusing solenoid.The experimental results tend to indicate a better beam brightness at smaller emittance for the electrostatic devices,although emittances measured for each focusing element were for a large part dependant on the tuning procedure developed to minimize the effects of the analyzing magnet. 展开更多
关键词 ECR Ion source EMITTANCE electrostatic focusing SOLENOID
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ECR Sputter Feed Developments at NSCL
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作者 D.Cole G.Machicoane +1 位作者 L.Tobos P.Zavodszky 《Chinese Physics C》 SCIE CAS CSCD 北大核心 2007年第S1期239-239,共1页
Production of metallic ion beams in support of the experimental program at the Coupled Cyclotron Facility at the NSCL required the development of ion sputtering feed of metallic molybdenum,nickel,uranium, and zirconiu... Production of metallic ion beams in support of the experimental program at the Coupled Cyclotron Facility at the NSCL required the development of ion sputtering feed of metallic molybdenum,nickel,uranium, and zirconium for use with the ARTEMIS ion source.The production of high intensity lower to medium charge state ions required high material consumption,posing some significant difficulties in reliable long term beam stability.Resultant and ongoing hardware and technique developments to resolve these difficulties will be presented in this poster along with interesting effects of the ion source solenoid field polarity on the sputtering process. 展开更多
关键词 金属离子 研究进展 溅射
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Dense matter with eXTP 被引量:1
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作者 Anna L.Watts WenFei Yu +74 位作者 Juri Poutanen Shu Zhang Sudip Bhattacharyya Slavko Bogdanov Long Ji Alessandro Patruno Thomas E.Riley Pavel Bakala Altan Baykal Federico Bernardini Ignazio Bombaci Edward Brown Yuri Cavecchi Deepto Chakrabarty Jér?me Chenevez Nathalie Degenaar Melania Del Santo Tiziana Di Salvo Victor Doroshenko Maurizio Falanga Robert D.Ferdman Marco Feroci Angelo F.Gambino MingYu Ge Svenja K.Greif Sebastien Guillot Can Gungor Dieter H.Hartmann Kai Hebeler Alexander Heger Jeroen Homan Rosario Iaria Jean in 't Zand Oleg Kargaltsev Aleksi KurkelaTheoretical Physics Department CERN XiaoYu Lai Ang Li XiangDong Li ZhaoSheng Li Manuel Linares FangJun Lu Simin Mahmoodifar Mariano Méndez M.Coleman Miller Sharon Morsink Joonas N?ttil? Andrea Possenti Chanda Prescod-Weinstein JinLu Qu Alessandro Riggio Tuomo Salmi Andrea Sanna Andrea Santangelo Hendrik Schatz Achim Schwenk LiMing Song Eva?rámková Benjamin Stappers Holger Stiele Tod Strohmayer Ingo Tews Laura Tolos Gabriel T?r?k David Tsang Martin Urbanec Andrea Vacchi RenXin Xu YuPeng Xu Silvia Zane GuoBao Zhang ShuangNan Zhang WenDa Zhang ShiJie Zheng Xia Zhou 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2019年第2期28-44,共17页
In this White Paper we present the potential of the Enhanced X-ray Timing and Polarimetry(eXTP) mission for determining the nature of dense matter; neutron star cores host an extreme density regime which cannot be rep... In this White Paper we present the potential of the Enhanced X-ray Timing and Polarimetry(eXTP) mission for determining the nature of dense matter; neutron star cores host an extreme density regime which cannot be replicated in a terrestrial laboratory. The tightest statistical constraints on the dense matter equation of state will come from pulse profile modelling of accretion-powered pulsars, burst oscillation sources, and rotation-powered pulsars. Additional constraints will derive from spin measurements, burst spectra, and properties of the accretion flows in the vicinity of the neutron star. Under development by an international Consortium led by the Institute of High Energy Physics of the Chinese Academy of Sciences, the eXTP mission is expected to be launched in the mid 2020 s. 展开更多
关键词 NEUTRON X-rays DENSE MATTER EQUATION of STATE
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Discovery of Nuclei at and Beyond the Proton Dripline
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作者 M. Thoennessen 《原子核物理评论》 CAS CSCD 北大核心 2016年第2期117-121,共5页
In contrast to the neutron dripline the proton dripline has been reached almost across the whole nuclear chart. However, because of the Coulomb barrier relatively long-lived isotopes can exist beyond the proton dripli... In contrast to the neutron dripline the proton dripline has been reached almost across the whole nuclear chart. However, because of the Coulomb barrier relatively long-lived isotopes can exist beyond the proton dripline. It is estimated that about 200 new isotopes at and beyond the proton dripline should be able to be discovered in the future. A brief review of the discovery of proton-rich nuclides as well as an outlook for the discovery potential in the future is presented. 展开更多
关键词 proton dripline isotope discoveries
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Gammasphere上裂变丰中子核核结构若干前沿领域的新进展(Ⅰ:第一和第二部分)(英文)
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作者 罗亦孝 J.H.Hamilton +36 位作者 J.O.Rasmussen A.V.Ramayya C.Goodin A.V.Daniel N.J.Stone 朱胜江 J.K.Hwang 刘少华 C.J.Beyer 李科 H.L.Crowell D.Almehed S.Frauendorf A.Covello V.Dimitrov 张敬业 车兴来 姜卓 D.Fong A.Gelberg I.Stefanescu A.Gargano E.F.Jones P.M.Gore I.Y.Lee G.M.Ter-Akopian Yu.Ts.Oganessian M.A.Stoyer R.Donangelo 马文超 J.D.Cole J.Kormicki 张学谦 S.C.Wu J.Gilat T.N.Ginter S.J.Asztalos 《原子核物理评论》 CAS CSCD 北大核心 2010年第3期229-251,共23页
(第一和第二部分):使用Gammasphere多探测器系统对252Cf裂变源瞬发γ射线进行γ-γ-γ和γ-γ(θ)符合测量,裂变丰中子原子核核结构若干前沿领域的深入研究获得了新的进展。高达5.7×1011以上的三重和更高重符合事件的数据统计,以... (第一和第二部分):使用Gammasphere多探测器系统对252Cf裂变源瞬发γ射线进行γ-γ-γ和γ-γ(θ)符合测量,裂变丰中子原子核核结构若干前沿领域的深入研究获得了新的进展。高达5.7×1011以上的三重和更高重符合事件的数据统计,以及更少压缩的三维数据为宽广未知丰中子核区的寻找和研究提供了有利的条件。在具有重要物理意义的若干丰中子核区首次建立,或显著扩展了一批包括转晕态和转晕附近能态的高自旋能级纲图。在偶-偶丰中子核110,112Ru和108Mo中鉴别出了手征对称破缺结构。丰中子110,112Ru附近核的三轴形变基态具有最低的能量,在它们之中已确认了接近最大值的三轴形变。在这些Ru和Mo同位素中观察到的手征双线能带展示出手征破缺的一切特征,特别是其理想的能量简并,表明它们在迄今已报道的手征破缺结构中,具有最好的手征特性。研究了手征结构从具有γ软度的108Ru到具有大三轴形变的110,112Ru的过渡。斜轴推转(TAC)和随机相近似(RPA)理论计算成功地拟合了在这些偶-偶丰中子核中观察到的手征双线能带的特性,并指定其为软手征振动态。在这些偶-偶核中观察到的手征破缺不可能归纳为奇-奇核中那样的简化的几何图像。前者来自闭壳外所有中子的相互作用。对双幻核132Sn附近N=83同中素链的系统研究为这个极富吸引力的核区提供了大量新的谱学信息。N=83同中素135Te(Z=52),136I(Z=53),137Xe(Z=54),138Cs(Z=55)和139Ba(Z=56)的最新能级信息,特别是首次建立的138Cs高自旋能级纲图和壳模型理论计算表明,Z=50质子闭壳外少数g7/2价质子激发同N=82中子闭壳外之唯一f7/2价中子的耦合对该核区能级结构具有关键作用。观察到了132Sn和208Pb附近核区谱学信息的相似性和相对应的三粒子和五粒子态。在135Te中观察到了磁转动,这是在双幻核132Sn附近观察到的首例磁转动。 展开更多
关键词 (第一和第二部分):丰中子核 高自旋 转晕态 裂变 252Cf γ射线三重符合 角关联 Gammasphere多探测器系统 手征对称破缺 三轴形变 斜轴推转(TAC)计算 软手征振动 N=83同中数链 双幻核132Sn 壳模型计算 磁转动 谱学相似性
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Observatory science with eXTP 被引量:1
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作者 Jean J.M.in 't Zand Enrico Bozzo +181 位作者 JinLu Qu Xiang-Dong Li Lorenzo Amati Yang Chen Immacolata Donnarumma Victor Doroshenko Stephen A.Drake Margarita Hernanz Peter A.Jenke Thomas J.Maccarone Simin Mahmoodifar Domitilla de Martino Alessandra De Rosa Elena M.Rossi Antonia Rowlinson Gloria Sala Giulia Stratta Thomas M.Tauris Joern Wilms XueFeng Wu Ping Zhou Iván Agudo Diego Altamirano Jean-Luc Atteia Nils A.andersson M.Cristina Baglio David R.Ballantyne Altan Baykal Ehud Behar Tomaso Belloni Sudip Bhattacharyya Stefano Bianchi Anna Bilous Pere Blay Joao Braga Sφren Brandt Edward F.Brown Niccolo Bucciantini Luciano Burderi Edward M.Cackett Riccardo Campana Sergio Campana Piergiorgio Casella Yuri Cavecchi Frank Chambers Liang Chen Yu-Peng Chen Jér?me Chenevez Maria Chernyakova ChiChuan Jin Riccardo Ciolfi Elisa Costantini Andrew Cumming Antonino D'Aì Zi-Gao Dai Filippo D'Ammando Massimiliano De Pasquale Nathalie Degenaar Melania Del Santo Valerio D'Elia Tiziana Di Salvo Gerry Doyle Maurizio Falanga XiLong Fan Robert D.Ferdman Marco Feroci Federico Fraschetti Duncan K.Galloway Angelo F.Gambino Poshak Gandhi MingYu Ge Bruce Gendre Ramandeep Gill Diego G?tz Christian Gouiffès Paola Grandi Jonathan Granot Manuel Güdel Alexander Heger Craig O.Heinke Jeroen Homan Rosario Iaria Kazushi Iwasawa Luca Izzo Long Ji Peter G.Jonker Jordi José Jelle S.Kaastra Emrah Kalemci Oleg Kargaltsev Nobuyuki Kawai Laurens Keek Stefanie Komossa Ingo Kreykenbohm Lucien Kuiper Devaky Kunneriath Gang Li En-Wei Liang Manuel Linares Francesco Longo FangJun Lu Alexander A.Lutovinov Denys Malyshev Julien Malzac Antonios Manousakis Ian McHardy Missagh Mehdipour YunPeng Men Mariano Méndez Roberto P.Mignani Romana Mikusincova M.Coleman Miller Giovanni Miniutti Christian Motch Joonas Nättilä Emanuele Nardini Torsten Neubert Paul T.O'Brien Mauro Orlandini Julian P.Osborne Luigi Pacciani Stéphane Paltani Maurizio Paolillo Iossif E.Papadakis Biswajit Paul Alberto Pellizzoni Uria Peretz Miguel A.Pérez Torres Emanuele Perinati Chanda Prescod-Weinstein Pablo Reig Alessandro Riggio Jerome Rodriguez Pablo Rodríguez-Gil Patrizia Romano Agata Rózańska Takanori Sakamoto Tuomo Salmi Ruben Salvaterra andrea Sanna andrea Santangelo Tuomas Savolainen Stéphane Schanne Hendrik Schatz LiJing Shao andy Shearer Steven N.Shore Ben W.Stappers Tod E.Strohmayer Valery F.Suleimanov Jirí Svoboda F.-K.Thielemann Francesco Tombesi Diego F.Torres Eleonora Torresi Sara Turriziani andrea Vacchi Stefano Vercellone Jacco Vink Jian-Min Wang JunFeng Wang Anna L.Watts ShanShan Weng Nevin N.Weinberg Peter J.Wheatley Rudy Wijnands Tyrone E.Woods Stan E.Woosley ShaoLin Xiong YuPeng Xu Zhen Yan George Younes WenFei Yu Feng Yuan Luca Zampieri Silvia Zane andrzej A.Zdziarski Shuang-Nan Zhang Shu Zhang Shuo Zhang Xiao Zhang Michael Zingale 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2019年第2期97-138,共42页
In this White Paper we present the potential of the enhanced X-ray Timing and Polarimetry(eXTP) mission for studies related to Observatory Science targets. These include flaring stars, supernova remnants, accreting wh... In this White Paper we present the potential of the enhanced X-ray Timing and Polarimetry(eXTP) mission for studies related to Observatory Science targets. These include flaring stars, supernova remnants, accreting white dwarfs, low and high mass X-ray binaries, radio quiet and radio loud active galactic nuclei, tidal disruption events, and gamma-ray bursts. eXTP will be excellently suited to study one common aspect of these objects: their often transient nature. Developed by an international Consortium led by the Institute of High Energy Physics of the Chinese Academy of Science, the eXTP mission is expected to be launched in the mid 2020s. 展开更多
关键词 space research in struments nuclear astrophysics flare stars accretion and accretion disks mass loss and stellar winds cataclysmic binaries X-ray binaries supernova remnants active galactic nuclei X-ray bursts gamma-ray bursts gravitational waves
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