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Intermediate-mass black holes in Green pea galaxies(IMBH-GP)I:A candidate sample from LAMOST and SDSS

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Science china(Physics,Mechanics & astronomy) 2024年第10期67卷 147-161页

作者： Ruqiu Lin Zhen-Ya Zheng Fang-Ting Yuan jun-Xian Wang Chunyan Jiang Ning Jiang Lingzhi Wang Linhua Jiang Xiang Ji Shuairu Zhu Xiaodan Fu key laboratory for Research in Galaxies and Cosmology Shanghai Astronomical ObservatoryChinese Academy of SciencesShanghai 200030China School of astronomy and Space sciences University of Chinese Academy of SciencesBeijing 100049China CAS key laboratory for Research in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of ChinaHefei 230026China chinese academy of sciences South America Center for astronomy(CASSACA) National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China CAS key laboratory of {2. astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Kavli Institute for astronomy and Astrophysics Peking UniversityBeijing 100871China Department of astronomy School of PhysicsPeking UniversityBeijing 100871China

The scaling relation of central massive black holes(M_(BH)s)and their host galaxies is well-studied for supermassive BHs(SM_(BH)s,M_(BH)≥10^(6)M_(⊙)).However,this relation has large uncertainties in the mass range of the intermediate-mass BHs(IM_(BH)s,M_(BH)~10^(3)-10^(6)M_(⊙)).Since Green pea(GP)galaxies are luminous compact dwarf galaxies,which may be likely to host less massive SM_(BH)s or even IM_(BH)s,we systematically search for M_(BH)s in a large sample of 2.90 GP galaxies at zmass of 108.83±0.11M_(⊙)and hosts M_(BH)s with single-epoch virial masses ranging from M_(BH)~10^(4.7)to 10^(8.5)M_(⊙)(median 105.85±0.64M_(⊙)).Among the 59 M_(BH) candidates,36 have black hole masses M_(BH)≤10^(6)M_(⊙)(IM_(BH) candidates),one of which even has M_(BH)■10^(5)M_(⊙).We find that the M_(BH)-M_(*)relation of our M_(BH) sample is consistent with the M_(BH)-M_(bulge)relation for SM_(BH)s,while is above the M_(BH)-M_(*)relation for M_(BH)s in dwarf galaxies in the same mass ***,we show that 2. M_(BH) candidates,including 4 IM_(BH) candidates,have additional evidence of black hole activities,assessed through various methods such as the broad-line width,BPT diagram,mid-infrared color,X-ray luminosity,and radio *** studies show that it is very promising to find IM_(BH)s in GP galaxies,and the BH sample so obtained enables us to probe the connection between the M_(BH)s and compact dwarf galaxies in the low-redshift Universe.

关键词： SMBHs IMBHs Green pea galaxies compact dwarf galaxies

The optical Variability Properties of TeV Blazars

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Research in astronomy and Astrophysics 2024年第9期24卷 66-75页

作者： Zi-An Su Wen-Xin Yang Xiang-Tao Zeng Le-Jian Ou Ze-Lin Li Jiang-He Yang jun-Hui Fan Department of Physics School of Physics and ElectronicsHunan Normal UniversityChangsha 410081China Center for Astrophysics Guangzhou UniversityGuangzhou 510006China Greater Bay Brand Center of the national astronomical Data Center Guangzhou 510006China astronomy Science and Technology Research laboratory of Department of Education of Guangdong Province Guangzhou 510006China College of Microelectronics Feicuihu Campus of Hefei University of TechnologyHefei 230601China College of mathematics and Physics Science Hunan University of Arts and ScienceChangde 415000China

Variability is one of the typical observational properties of blazars and the spectral changes are usually associated with variability,although this kind of association is unclear *** this work,we used data from the Steward Observatory blazar monitoring program to investigate the optical variability properties including the short-term timescale,the brightness-dependent spectral property,the correlation between the the brightness variation and the polarization,and then estimate the Doppler factors based on the obtained short timescale to study the polarization property for a sample of 2. TeV *** analyses arrive at the following results:(1)The largest variation amplitude in R-band,ΔR_(M),covers a range from ΔR_(M)=0.2. mag(1ES 2.44+514)to ΔR_(M)=4.66 mag(3C 2.9).(2.Intra-day variability was found from five sources with timescales from 0.14 day for S50716+714 to 0.98 day for PKS *** sources show spectra that are bluer when they become brighter,suggesting a common bluer-when-brighter property.(3)The plot of the polarization versus estimated Doppler factor is consistent with the Doppler factor dependent formula of polarization.(4)The largest polarization is correlated with the largest optical variation,suggesting that the high polarization and high amplitude variation are both the indicator of beaming effect.

关键词： galaxies:active galaxies:jets radiation mechanisms:non-thermal

The dusty and extremely red progenitor of the typeⅡsupernova 2.2.ixf in Messier 101

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Science china(Physics,Mechanics & astronomy) 2024年第1期67卷 160-172页

作者： Danfeng Xiang jun Mo Lingzhi Wang Xiaofeng Wang Jujia Zhang Han Lin Lifan Wang Department of Physics Tsinghua UniversityBeijing 100084China South America Center for astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Beijing Planetarium Beijing Academy of Sciences and TechnologyBeijing 100044China Yunnan observatories Chinese Academy of SciencesKunming 650216China key laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China International Centre of Supernovae Yunnan Key LaboratoryKunming 650216China Mitchell Institute for Fundamental Physics and astronomy Texas A&M UniversityCollege StationTX 77843USA

Stars with initial masses in the range of 8-2. solar masses are thought to end their lives as hydrogen-rich supernovae(SNeⅡ).Based on the pre-explosion images of Hubble space telescope(HST)and Spitzer space telescope,we place tight constraints on the progenitor candidate of type IIP SN 2.2.ixf in Messier *** of the spectral energy distribution(SED)of its progenitor with dusty stellar spectral models results in an estimation of the effective temperature as 3091+*** luminosity is estimated as lg(L/L⊙)~4.83,consistent with a red supergiant(RSG)star with an initial mass of 12.1+2.⊙.The derived mass loss rate(6×10^(-6)-9×10^(-6)M⊙yr^(-1))is much lower than that inferred from the flash spectroscopy of the SN,suggesting that the progenitor experienced a sudden increase in mass loss when approaching the final *** the infrared bands,significant deviation from the range of regular RSGs in the color-magnitude diagram and period-luminosity space of the progenitor star indicates enhanced mass loss and dust *** with new evidence of polarization at the early phases of SN 2.2.ixf,such a violent mass loss is likely a result of binary interaction.

关键词： stellar evolution mass loss red supergiants infrared emission supernovae

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SAGE巡天介绍Ⅰ--测光系统和数据处理

天文学进展 2018年第2期36卷 101-121页

作者：范舟赵刚王炜赵景昆郑捷谈克峰刘玉娟何维宋轶晗姜晓军马路中国科学院光学天文重点实验室国家天文台北京100101 中国科学院大学天文与空间科学学院北京100049 中国科学院南美天文中心中智联合天文中心智利圣地亚哥7550000 中国科学院新疆天文台乌鲁木齐830011

SAGE(Stellar Abundance and Galactic Evolution)巡天采用一套对恒星大气参数敏感的独特测光系统,包括uSC,vSAGE,g,r,i,Hα_n,Hα_w和λ_(DDO51)(David Dunlap Observatory,DDO)共8个波段。该系统对恒星大气参数(有效温度T_(eff)、表面重力lg g和金属丰度[Fe/H])和星际消光的测量比传统的uvbyβ系统(Str?mgren-Crawford,SC)更敏感。由于g,r,i波段带宽较宽,因而观测效率较高,对恒星大气参数的测量精度和观测效率均超过uvbyβ系统和宽带测光系统。利用美国亚利桑那大学Steward天文台2.3 m Bok望远镜、新疆天文台南山1 m望远镜和乌兹别克斯坦maO(maidanak {2. Observatory)1 m望远镜已展开巡天观测。项目计划在约4年时间内完成所有的巡天观测,北天天区覆盖面积约12.00(~?)~2.高精度测光(信噪比为100σ)深度约15 mag(V波段);5σ探测极限可深至约2. mag(V波段)。最终将探测约5×108颗恒星,并得出其恒星大气参数以及星际消光。该样本比之前的u,v,b,y,β测光巡天,如GCS(Geneva-Copenhagen Survey)巡天和HM(Hauck and Mermilliod 1998)巡天,扩展到更深的区域,即深度达到7～8 mag(V波段)。利用观测得到的大样本恒星测光星表,可以开展如下课题的研究:(1)得到银河系约5×10~8颗恒星大样本的金属丰度分布,并根据恒星演化模型得到其年龄分布;(2.预期搜寻到一批贫金属星候选体,并利用其他望远镜进行下一步观测;(3)结合高质量的uSC波段数据,预期可以找到一批白矮星;(4)结合其他星表,预期找到一批长周期变源以及移动天体;(5)结合uSC波段数据和其他星表,预期可以找到一批类星体。

关键词：测光系统数据处理流量定标天测定标银河系结构

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基于随机光纤激光器的多奇点涡旋光束

光学学报 2024年第10期44卷 393-403页

作者：马小雅叶俊梁峻锐何俊鸿张扬许将明周朴姜宗福国防科技大学前沿交叉学科学院湖南长沙410073 国防科技大学南湖之光实验室湖南长沙410073 国防科技大学高能激光技术湖南省重点实验室湖南长沙410073

部分相干结构光束具有抗湍流闪烁和抑制散斑等特性,在大气传输和成像等领域具有广泛的应用潜力。提出并展示了基于随机光纤激光器产生的部分相干多奇点涡旋光束。对不同拓扑荷数涡旋光束的相干叠加进行仿真研究,发现叠加过程可产生具有... 详细信息

部分相干结构光束具有抗湍流闪烁和抑制散斑等特性,在大气传输和成像等领域具有广泛的应用潜力。提出并展示了基于随机光纤激光器产生的部分相干多奇点涡旋光束。对不同拓扑荷数涡旋光束的相干叠加进行仿真研究,发现叠加过程可产生具有多个奇点的复杂相位分布。采用中心波长为1081.3 nm的随机光纤激光器作为照明光源,通过搭建空间干涉环路实现多奇点涡旋光束的产生。奇点数目可通过改变参与干涉的涡旋拓扑荷数来实现灵活调控。该工作有望为多粒子控制、涡旋光通信、光学计算和成像等领域提供重要参考。

关键词：激光器随机光纤激光器多奇点涡旋涡旋叠加奇点可控部分相干

astronomically modulated late Pliocene equatorial Pacific climate transition and Northern Hemisphere ice sheet expansion

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chinese Science Bulletin 2010年第2期55卷 212-220页

作者： ma WenTao TIAN jun LI QianYu State key laboratory of {2.rine Geology Tongji University Shanghai 200092 China

The equatorial Pacific underwent a significant climate transition during the late Pliocene, which is characterized by cooling of global sea surface temperatures (SSTs) and formation of a marked SST gradient between the eastern and western equatorial Pacific. Moreover, this transition was nearly synchronous with the late Pliocene Northern Hemisphere glaciation. Probing the relationship among solar insolation, low and high latitude processes is the key to unravel the mechanism of this climate transition. A series of statistical methods were used in this study to analyze the orbital components of the equatorial Pacific SST and global ice volume records for the past 5 ma. We found that integrated solar insolation rather than the monthly mean insolation is the primary external forcing of the late Pliocene climate transition, and that on orbital time scale the SSTs of the eastern and western equatorial Pacific display consistent change rather than a "seesaw" pattern. Changes of Earth’s orbital configuration have been responsible for this climate transition whereas the feedback effects of atmospheric CO2.concentration have further cooled the global climate since the early Cenozoic.

关键词：赤道太平洋全球气候上新世北半球晚期数字调制冰盖赤道西太平洋

Hydrothermal synthesis of two-dimensional MoS_(2.and its applications

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Tungsten 2019年第1期1卷 59-79页

作者： Xiaoyan Zhang Guoqing ma jun Wang laboratory of Micro-Nano Optoelectronic materials and Devices Key Laboratory of Materials for High-Power LaserShanghai Institute of Optics and Fine Mechanics(SIOM)Chinese Academy of Sciences(CAS)Shanghai 201800China Center of materials Science and Optoelectronic Engineering University of Chinese Academy of SciencesBeijing 100049China State key laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine Mechanics(SIOM)Chinese Academy of Sciences(CAS)Shanghai 201800China CAS Center for Excellence in Ultra-intense Laser Science(CEULS) Shanghai 201800China

Two-dimensional(2.)transition metal dichalcogenides(TMDs)have attracted tremendous attention because of their unique electronic,optical and chemical properties.2. TMDs,especially 2. MoS2.have been proved to show great potential in vari-ous applications such as sensing,hydrogen evolution and lithium ion ***,methods for the scalable preparation of 2. materials and 2. nanocomposites of high quality and low cost must be *** the various synthesis meth-ods,the hydrothermal synthesis method is simple and can meet the above *** this review,the recent advances in the controllable hydrothermal synthesis of 2. MoS_(2.and its nanocomposites by the hydrothermal synthesis method are *** provide insight into the growth mechanisms of few-layered 2. MoS_(2.with different morphologies and the key technologies to realize wafer-scale growth of continuous and homogeneous 2. films which are important for practical ***,the typical applications of TMDs in nonlinear optics as ultrafast optical modulation devices are pre-sented based on work of our *** more clarity,we summarize the current challenges of the hydrothermal synthesis method encountering,and suggest solutions to these challenges concerning future developments in practical applications.

关键词： Hydrothermal synthesis Transition metal dichalcogenides MoS_(2. Two dimension Nonlinear optics

The kinematics of an untwisting solar jet in a polar coronal hole observed by SDO/AIA

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Research in astronomy and Astrophysics 2012年第5期12卷 573-583页

作者： Hua-Dong Chen jun Zhang Su-Li ma College of Science China University of Petroleum Qingdao 266555 China key laboratory of Solar Activity National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Harvard-Smithsonian Center for Astrophysics MA 02138 U 5A

Using the multi-wavelength data from the Atmospheric Imaging Assembly （AIA） onboard the Solar Dynamics Observatory （SDO） spacecraft, we study a jet occurring in a coronal hole near the northern pole of the Sun. The jet presented distinct upward helical motion during ejection. By tracking six identified moving features （MFs） in the jet, we found that the plasma moved at an approximately constant speed along the jet＇s axis. Meanwhile, the MFs made a circular motion in the plane transverse to the axis. Inferred from linear and trigonometric fittings to the axial and transverse heights of the six tracks, the mean values of the axial velocities, transverse velocities, angular speeds, rotation periods, and rotation radii of the jet are 114 km s-1, 136 km s-1, 0.81° s-1, 452.s and 9.8 × 10^3 km respectively. As the MFs rose, the jet width at the corresponding height increased. For the first time, we derived the height variation of the longitudinal magnetic field strength in the jet from the assumption of magnetic flux conservation. Our results indicate that at heights of 1 × 10^4 -7 × 10^4 km from the base of the jet, the flux density in the jet decreases from about 15 to 3 G as a function of B = 0.5（R/R） - 1）-0.84 （G）. A comparison was made with other results in previous studies.

关键词： Sun activity -- Sun chromosphere -- Sun magnetic fields -- Sun flares -- Sun rotation

Dense molecular gas tracers in high mass star formation regions

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Research in astronomy and Astrophysics 2016年第2期16卷 33-44页

作者： Hong-jun ma Yu Gao Jing-Wen Wu Purple Mountain Observatory/key laboratory of Radio {2. Chinese Academy of SciencesNanjing 210008China Department of Physics and astronomy University of CaliforniaLos AngelesCA 90095USA national astronomical observatories Chinese Academy of SciencesBeijing 100012China

We report the FCRAO observations that mapped HCN （1-0）, CS （2.1）, HNC （1-0） and HCO＋（1-0） in ten high-mass star forming cores associated with water masers. We present velocity integrated intensity maps of the four lines for these dense cores, compare their line profiles, and derive physical properties of these cores. We find that these four tracers identify areas with similar properties in these massive dense cores, and in most cases, the emissions of HCN and HCO＋ are stronger than those of HNC and CS. We also use the line ratios of HCO＋/HCN, HNC/HCN and HNC/HCO＋ as the diagnostics to explore the environment of these high-mass star forming regions, and find that most of the cores agree with the model that photodominated regions dominate the radiation field, except for W44, for which the radiation field is similar to an X-ray dominated region.

关键词： ISM clouds -- ISM molecules -- stars formation