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The Distribution of UV Radiation Field in the Molecular Clouds of Gould Belt

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Research in Astronomy and Astrophysics 2022年第8期22卷 206-217页

作者： Jifeng Xia Ningyu Tang qijun zhi Sihan Jiao Jinjin Xie Gary A.Fuller Paul F.Goldsmith Di Li School of Physics and Electronic Science Guizhou Normal UniversityGuiyang 550025China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Department of Physics Anhui Normal UniversityWuhu 241002China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal UniversityGuiyang 550001China Shanghai Astronomical Observatory CASShanghai 200030China Jodrell Bank Centre for Astrophysics Department of Physics&AstronomyThe University of ManchesterManchester M139PLUnited Kingdom I.Physikalisches Institut University of CologneZülpicher Str.77D-50937 KölnGermany Jet Propulsion Laboratory California Institute of Technology4800 Oak Grove DrivePasadenaCA 91109United States of America

The distribution of ultraviolet(UV)radiation field provides critical constraints on the physical environments of molecular *** 1 kpc of our solar system and fostering protostars of different masses,the giant molecular clouds in the Gould Belt present an excellent opportunity to resolve the UV field structure in star-forming *** performed spectral energy distribution(SED)fitting of the archival data from the Herschel Gould Belt Survey(HGBS).Dust radiative transfer analysis with the DUSTY code was applied to 23 regions in 14 molecular complexes of the Gould Belt,resulting in the spatial distribution of the radiation field in these *** 10 of 15 regions with independent measurements of star formation rate,their star formation rate and UV radiation intensity largely conform to a linear correlation found in previous studies.

关键词： ISM:clouds (ISM:)dust extinction radiative transfer

Galactic interstellar scintillation observed from four globular cluster pulsars by FAST

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Science China(Physics,Mechanics & Astronomy) 2023年第9期66卷 119-127页

作者： Dandan Zhang Zhenzhao Tao Mao Yuan Jumei Yao Pei Wang qijun zhi Weiwei Zhu Xun Shi Michael Kramer Di Li Lei Zhang Guangxing Li School of Mathematical Sciences School of Physics and Electronic SciencesGuizhou Normal UniversityGuiyang 550001China National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guiyang 550001China Department of Astronomy Beijing Normal UniversityBeijing 100875China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China South-Western Institute for Astronomy Research(SWIFAR) Yunnan UniversityKunming 650000China Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China Max-Planck Institut fr Radioastronomie Bonn D-53121Germany Key Laboratory of Radio Astronomy and Technology Chinese Academy of SciencesBeijing 100101China Computational Astronomy Platform Zhejiang LabHangzhou 311121China

We report detections of scintillation arcs for pulsars in globular clusters M5,M13 and M15 for the first time using the Fivehundred-meter Aperture Spherical radio Telescope(FAST).From observations of these arcs at multiple epochs,we infer that screen-like scattering medium exists at distances 4.1_(-0.3)^(+0.2),6.7_(-0.2)^(+0.2)and 1.3_(-1.0)^(+0.7) kpc from Earth in the directions of M5,M13 and M15,*** means M5's and M13's scattering screens are located at 3.0_(-0.2)^(+0.1) and 4.4_(-0.1)^(+0.1) kpc above the galactic plane,whereas,M15's is at 0.6_(-0.5)^(+0.3) kpc below the *** estimate the scintillation timescale and decorrelation bandwidth for each pulsar at each epoch using the one-dimensional auto-correlation in frequency and time of the dynamic *** found that the boundary of the Local Bubble may have caused the scattering of M15,and detected the most distant off-plane scattering screens to date through pulsar scintillation,which provides evidence for understanding the medium circulation in the Milky Way.

关键词： pulsars scintillation globular clusters

同方期刊数据库

Long-term variations of X-ray pulse profiles for the Crab pulsar:data analysis and modeling

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Science China(Physics,Mechanics & Astronomy) 2020年第10期63卷 111-131页

作者： LunHua Shang YuanJie Du XiangQun Cui ShiJun Dang JiGuang Lu JunTao Bai qijun zhi YouLi Tuo LinLi Yan LiangWei Huang XinYuan Zhang XiaoMin Bei QingQing Lin GuoJun Qiao Hua Shen RiHong Zhu School of Electronic and Optical Engineering Nanjing University of Science and TechnologyNanjing 210094China Qian Xuesen Laboratory of Space Technology Beijing 100094China Nanjing Institute of Astronomical Optics and Technology National Astronomical ObservatoriesChinese Academy of SciencesNanjing 210042China XinJiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China CAS Key Laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Guizhou Radio Astronomy Observatory Chinese Academy of SciencesGuiyang 550025China School of Physics and Electronic Science Guizhou Normal UniversityGuiyang 550001China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal UniversityGuiyang 550001China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China School of Physics Peking UniversityBeijing 100871China Key Laboratory of Advanced Solid Laser Nanjing University of Science and TechnologyNanjing 210094China

The pulse profiles of the Crab pulsar(as well as some other pulsars)vary with *** can lead to a major source of intrinsic timing noise,which lacks a detailed physical *** phase separation?between the first left peak(P1)and the second right peak(P2)is a key parameter that shows the variations of pulse profiles for the Crab *** was found that the evolution of?has a tendency with increasing rates of 0.82?±0.25?,0.80?±0.54?,and 0.77?±0.28?per century for the 2-6,6-15,and15-60 ke V bands,***,the flux ratios(P2/P1)of X-ray pulse profiles in the three bands were calculated,and the derived flux ratios were consistent with the radio and X-ray measurements of the *** addition to discovering the physical origin of the pulse changes,the high-SNR X-ray pulse profiles were simulated in the annular gap model,and two model parameters(e.g.,the maximum emission heights of the two peaks)were observed to slightly affect the variations of peak *** fitted the long-term variations of emission heights of the two peaks and discovered that the emission heights showed increasing tendencies with *** of these emission heights induced a characteristic period derivative,and a complete formula for both the magnetic dipole radiation and wind-particle-induced variations of the moment of inertia was used for the pulsar’s spin-down to obtain the variation rate˙αof the magnetic inclination angle,which was-1.60?per *** timing noise is observed to be mainly induced by the variations of pulse profiles,which might correlate with a characteristic spin period derivative arising from the fluctuations of the emission *** work will lay a foundation for understanding the origin of intrinsic timing noise and making high-precision timing models in the future.

关键词： radiation mechanisms pulsars X-ray

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远离稳定线附近β^-衰变寿命的新规律

云南大学学报（自然科学版） 2009年第5期31卷 489-492,498页

作者：支启军张小平贵州师范大学物理与电子科学学院贵州贵阳550001 南京大学物理系江苏南京210093

系统分析了远离β稳定线原子核β-衰变寿命的实验数据,发现在各同位素链上,远离β稳定线原子核的β-衰变寿命与母核的质子和中子数之间存在着指数规律.在理论分析的基础上,提出了远离β稳定线原子核β-衰变寿命的一套四参数理论计算公式... 详细信息

系统分析了远离β稳定线原子核β-衰变寿命的实验数据,发现在各同位素链上,远离β稳定线原子核的β-衰变寿命与母核的质子和中子数之间存在着指数规律.在理论分析的基础上,提出了远离β稳定线原子核β-衰变寿命的一套四参数理论计算公式,理论计算结果与现有实验数据符合较好.此外,利用该公式对一些远离稳定线原子核的β-衰变寿命作了理论预言.

关键词： β-衰变寿命指数规律计算公式

从宋代“客星”到中国“天眼”中的脉冲星——“李约瑟难题”试答

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科技导报 2018年第12期36卷 15-21页

作者：张承民杨佚沿支启军中国科学院国家天文台中国科学院FAST重点实验室北京100101 中国科学院大学物理科学学院北京100049 北京师范大学天文系北京100875 贵州师范大学物理与电子科学学院贵州省射电天文数据处理重点实验室贵阳550001

研究和分析了中国古代天文学的辉煌成就与当今中国＂天眼＂——500 m口径球面射电望远镜（FAST）科学目标——脉冲星的关系。针对宋朝天文学家记录的客星与FAST正在进行的脉冲星观测,详述了宋代客星记录在世界科技史上的贡献;介绍了脉... 详细信息

研究和分析了中国古代天文学的辉煌成就与当今中国＂天眼＂——500 m口径球面射电望远镜（FAST）科学目标——脉冲星的关系。针对宋朝天文学家记录的客星与FAST正在进行的脉冲星观测,详述了宋代客星记录在世界科技史上的贡献;介绍了脉冲星发现历史与基本天体物理特征,以及脉冲星作为FAST科学目标的意义。以客星到脉冲星的千年追寻为线索,探索和尝试回答＂李约瑟难题＂,认为现代科学是人类文明共同体的长期探索结晶,中国在科学早期的发育过程中播撒了创新火种,而西方在文艺复兴运动中不断完善了科学体系,其中东西方科技的交流与传播得益于蒙古帝国在丝绸之路的远征与开拓。

关键词：脉冲星中子星引力波 FAST 李约瑟难题

FAST discovery of an extremely radio-faint millisecond pulsar from the Fermi-LAT unassociated source 3FGL J0318.1+0252

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Science China(Physics,Mechanics & Astronomy) 2021年第12期64卷 10-17页

作者： Pei Wang Di Li Colin J.Clark Pablo M.Saz Parkinson Xian Hou Weiwei Zhu Lei Qian Youling Yue zhichen Pan zhijie Liu Xuhong Yu Shanping You Xiaoyao Xie qijun zhi Hui Zhang Jumei Yao Jun Yan Chengmin Zhang Kwok Lung Fan Paul S.Ray Matthew Kerr David A.Smith Peter F.Michelson Elizabeth C.Ferrara David J.Thompson zhiqiang Shen Na Wang FAST&Fermi-LAT Collaboration CAS Key Laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Jodrell Bank Centre for Astrophysics Department of Physics and AstronomyUniversity of ManchesterManchester M139PLUK Department of Physics and Laboratory for Space Research University of Hong KongHong Kong 999077China Santa Cruz Institute for Particle Physics University of CaliforniaSanta Cruz CA 95064USA Yunnan Observatories Chinese Academy of SciencesKunming 650216China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China School of Computer Science and Technology Key Laboratory of Information and Computing Guizhou ProvinceGuizhou Normal UniversityGuiyang 550001China School of Physics and Electronic Science Guizhou Normal UniversityGuiyang 550001China Physics Department Stanford UniversityStanford CA 94305USA UMCP/CRESST/GSFC NASAGreenbeltMaryland MD 20771USA GSFC NASAGreenbeltMaryland MD 20771USA Centre d’´Etudes Nucl´eaires de Bordeaux Gradignan IN2P3/CNRSUniversit´e BordeauxGradignan 33175France Space Science Division U.S.Naval Research LaboratoryWashington DC 20375-5352USA Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China Xinjiang Astronomical Observatory Urumqi 830011China Department of Physics University of MarylandCollege Park MD 20742USA NAOC-UKZN Computational Astrophysics Centre University of KwaZulu-NatalDurban 4000South Africa 不详

High sensitivity radio searches of unassociated γ-ray sources have proven to be an effective way of finding new pulsars. Using the Five-hundred-meter Aperture Spherical radio Telescope(FAST) during its commissioning phase, we have carried out a number of targeted deep searches of Fermi Large Area Telescope(LAT) γ-ray sources. On February 27, 2018 we discovered an isolated millisecond pulsar(MSP), PSR J0318+0253, coincident with the unassociated γ-ray source 3 FGL J0318.1+0252. PSR J0318+0253 has a spin period of 5.19 ms, a dispersion measure(DM) of 26 pc cm-3 corresponding to a DM distance of about 1.3 kpc, and a period-averaged flux density of(~11±2) μJy at L-band(1.05-1.45 GHz). Among all high energy MSPs, PSR J0318+0253 is the faintest ever detected in radio bands, by a factor of at least ~4 in terms of L-band fluxes. With the aid of the radio ephemeris, an analysis of 9.6 years of Fermi-LAT data revealed that PSR J0318+0253 also displays strong γ-ray pulsations. Follow-up observations carried out by both Arecibo and FAST suggest a likely spectral turn-over around 350 MHz. This is the first result from the collaboration between FAST and the Fermi-LAT teams as well as the first confirmed new MSP discovery by FAST, raising hopes for the detection of many more MSPs. Such discoveries will make a significant contribution to our understanding of the neutron star zoo while potentially contributing to the future detection of gravitational waves, via pulsar timing array(PTA) experiments.

关键词： FAST pulsar radio gamma rays

PSR J0826+2637的模式变换特性研究

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北京师范大学学报（自然科学版） 2023年第1期59卷 31-37页

作者：林权伟党世军支启军白俊涛许鑫贵州师范大学物理与电子科学学院贵州贵阳550025

利用FAST在中心频率为1.25 GHz的观测数据,分析了PSR J0826+2637的单脉冲能量分布和调制特性,发现存在新的模式变换,并探讨了不同模式的平均脉冲轮廓和偏振特性.结果显示:在B模式中存在强、弱2种模式,弱模式中存在脉冲消零(PN)现象,脉... 详细信息

利用FAST在中心频率为1.25 GHz的观测数据,分析了PSR J0826+2637的单脉冲能量分布和调制特性,发现存在新的模式变换,并探讨了不同模式的平均脉冲轮廓和偏振特性.结果显示:在B模式中存在强、弱2种模式,弱模式中存在脉冲消零(PN)现象,脉冲消零比(NF)为2.7%;在强、弱2种模式中,中间脉冲的偏振结果差异较小,而主脉冲的变化较大.PSR J0826+2637的模式变换特性很难用现有的模型来解释.

关键词：脉冲星模式变换偏振 PSR J0826+2637

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脉冲星衍射式闪烁观测研究进展

北京师范大学学报（自然科学版） 2020年第1期56卷 22-29页

作者：陶振钊王培姚菊枚朱炜玮支启军董爱军贵州师范大学物理与电子科学学院贵州贵阳550025 中国科学院国家天文台北京100101 贵州师范大学贵州省射电天文数据处理重点实验室贵州贵阳550025

介绍脉冲星星际闪烁效应产生的机制,简要描述衍射式闪烁的观测研究方法,并总结了近些年衍射式闪烁观测研究的进展,主要包含使用闪烁效应限制星际介质电子密度涨落谱、估算脉冲星切向速度、分辨脉冲星射电辐射区尺度、获取脉冲星双星轨... 详细信息

介绍脉冲星星际闪烁效应产生的机制,简要描述衍射式闪烁的观测研究方法,并总结了近些年衍射式闪烁观测研究的进展,主要包含使用闪烁效应限制星际介质电子密度涨落谱、估算脉冲星切向速度、分辨脉冲星射电辐射区尺度、获取脉冲星双星轨道参数、搜索脉冲星的非脉冲射电辐射等,以及总结了国内一些射电望远镜对脉冲星闪烁观测研究工作及FAST观测预期.

关键词：脉冲星星际介质散射闪烁

新冠疫情下“停课不停学”的大学物理GeoGebra仿真单摆实验

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大学物理实验 2021年第1期34卷 87-91页

作者：何秋静杨文韬王晓雅支启军贵州师范大学物理与电子科学学院贵州贵阳550000 六盘水师范学院物理与电气工程学院贵州六盘水553004

基于GeoGebra的动态数学软件的技术路线,依此技术路线实施,制作单摆的仿真实验。此仿真实验操作简单、调试方便、与真实实验融合度高,教师不仅可以拿来当作学生的预习实验,也可以用来给学生讲解单摆的理论知识。

关键词： GeoGebra 5.0软件单摆演示与仿真