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The calibration and initial results of the HeI D3 line flash spectrum obtained during the 2008 total solar eclipse

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Science China(Physics,Mechanics & Astronomy) 2009年第11期52卷 1799-1805页

作者： li hui JI HaiSheng NI HouKun ZHANG HaiYing ZHANG YaNan liU HongRui DENG YuanYong WANG DongGuang DU QiuSheng ZHOU Tuanhui li JingWei SHEN JinHua purple mountain observatory 2 Nanjing 210008China nanjing Institute of astronomical Optics&Technology Nanjing 210042China national astronomical observatories of China Beijing 100012China

The flash spectra in the HeI D3 line were obtained during the 2008 total solar eclipse. This paper describes the instrument and the calibration of the obtained flash spectrum, and presents our initial results. The average integrated intensity is Eave = 8.13×1013 erg·cm-1· s-1·ster-1 at h = 1100 km, which confirms that the HeI D3 emission is negatively correlated with the solar activity. The surface brightness reaches a maximum of F ave = 8.25×105 erg·cm-2·s-1·ster-1 at about h ≈ (1290 ± 75) km and then decreases exponentially with height when h >1800 km with an exponential index β = 1.63×10-8 cm-1.

关键词： total solar eclipse flash spectrum spectral line

Revisit of Dynamical Mechanisms of Transporting Asteroids in the 3:1 Resonance to the Near-Earth Space

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chinese Journal of Astronomy and Astrophysics 2007年第1期7卷 148-154页

作者： Jiang-hui Ji lin liu purple mountain observatory Chinese Academy of Sciences Nanjing 210008 Department of Astronomy Nanjing University Nanjing 210093 national astronomical observatories Chinese Academy of Sciences Beijing 100012

It is well-known that the asteroids in the main belt trapped in the 3：1 Mean Motion Resonance （MMR） with Jupiter （at semi-major axes -2.5 AU） are few in number, forming one of the so-called Kirkwood Gaps. Wisdom pointed out that chaotic motion of such aster- oids can increase their eccentricities and make them approach and cross the orbit of Mars （or even the Earth）. We numerically investigated the orbital evolution of the asteroids involved in 3：1 MMR （NEOs） over millions of years and revisited the dynamical mechanisms of trasporitng such asteroids into the NEO region. The results show that the dynamical evolution of the asteroids around 2.5 AU is mainly dominated by the 3：1 resonance, the v5 and v6 secular resonances and the Kozai resonance, and these bodies can evolve into NEOs through several of the dynamical mechanisms, so indicating possible dynamical origin of the NEOs.

关键词： celestial mechanics-near-Earth Objects-mean motion resonance-secular resonance

On the radial velocity calibrations in the LAMOST medium-resolution spectroscopic survey of nebulae

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Research in Astronomy and Astrophysics 2021年第3期21卷 1-14页

作者： Juan-Juan Ren Hong Wu Chao-Jian Wu Wei Zhang Jian-Jun Chen Chih-Hao Hsia Fan Yang Chao liu Jian-Rong Shi Yu-Zhong Wu hui Zhu Bin li Zhong-Rui Bai Hao Tian Yong-hui Hou CAS Key Laboratory of Space Astronomy and Technology National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China CAS Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China national astronomical observatories Chinese Academy of SciencesBeijing 100101China State Key Laboratory of Lunar and Planetary sciences Macao University of Science and TechnologyTaipaMacaoChina University of chinese academy of sciences Beijing 100049China purple mountain observatory Chinese Academy of SciencesNanjing 210008China University of Science and Technology of China Hefei 230026China nanjing Institute of astronomical Optics&Technology National Astronomical ObservatoriesChinese Academy of SciencesNanjing 210042China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China

Accurate radial velocity determinations of optical emission lines(i.e.,[NⅡ]λλ6548,6584,Hαand[SⅡ]λλ6717,6731)are very important for investigating the kinematic and dynamic properties of *** second stage survey program of Large sky Area Multi-Object fiber Spectroscopic Telescope(LAMOST)has started a sub-survey of nebulae(MRS-N)which will spectroscopically observe the optical emission lines of a large sample of nebulae near the Galactic *** now,15 MRS-N plates have been observed from September 2017 to June *** on fitting the sky emission lines in the red band spectra of MRS-N,we investigate the precision of wavelength calibration and find there are systematic deviations of radial velocities(RVs)from~0.2 to 4 km s^(-1) for different *** for the plates obtained in March 2018,the systematic deviations of RVs can be as large as~4 km s^(-1),which then go down to~0.2-0.5 kms^(-1) at the end of 2018 and January *** RV calibration function is proposed for these MRS-N plates,which can simultaneously and successfully calibrate the systematic deviations and improve the precision of RVs.

关键词： ISM:general ISM:kinematics and dynamics technique:spectroscopic technique:radial velocities

LAMOST Medium-Resolution Spectral Survey of Galactic Nebulae(LAMOST MRS-N):An overview of scientific goals and survey plan

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Research in Astronomy and Astrophysics 2021年第4期21卷 243-252页

作者： Chao-Jian Wu Hong Wu Wei Zhang Juan-Juan Ren Jian-Jun Chih-Hao Hsia Yu-Zhong Wu hui Zhu Bin li Yong-hui Hou Jun-lin Wang Shuo-Ran Yu CAS Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China CAS Key Laboratory of Space Astronomy and Technology National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China national astronomical observatories Chinese Academy of SciencesBeijing 100101China State Key Laboratory of Lunar and Planetary sciences Macao University of Science and TechnologyTaipaMacaoChina purple mountain observatory Chinese Academy of SciencesNanjing 210008China University of Science and Technology of China Hefei 230026China nanjing Institute of astronomical Optics &TechnologyNational Astronomical ObservatoriesChinese Academy of SciencesNanjing 210042China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China

Since Sep.2018,LAMOST has started the medium-resolution(R~7500)spectral survey(MRS).We proposed the spectral survey of Galactic nebulae,including HⅡregions,HH objects,supernova remnants,planetary nebulae and the special stars with MRS(LAMOST MRS-N).LAMOST MRS-N covers about 1700 square degrees of the northern Galactic plane within 40°

关键词： surveys ISM:general ISM:HII regions ISM:Herbig-Haro objects ISM:planetary nebulae: ISM:supernova remnants Galaxy:disk

The Data Processing of the LAMOST Medium-resolution Spectral Survey of Galactic Nebulae(LAMOST MRS-N Pipeline)

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Research in Astronomy and Astrophysics 2022年第7期22卷 224-234页

作者： Chao-Jian Wu Hong Wu Wei Zhang Yao li Juan-Juan Ren Jian-Jun Chen Chih-Hao Hsia Yu-Zhong Wu hui Zhu Bin li Yong-hui Hou CAS Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China national astronomical observatories Chinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China CAS Key Laboratory of Space Astronomy and Technology National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China State Key Laboratory of Lunar and Planetary sciences Macao University of Science and TechnologyTaipaMacaoChina purple mountain observatory Chinese Academy of SciencesNanjing 210008China University of Science and Technology of China Hefei 230026China 8 nanjing Institute of astronomical Optics&Technology National Astronomical ObservatoriesChinese Academy of SciencesNanjing 210042China

The Large sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST) medium-resolution spectral survey of Galactic Nebulae(MRS-N) has conducted for more than three years since 2018 September and observed more than190 thousand nebular spectra and 20 thousand stellar ***,there is not yet a data processing pipeline for nebular *** significantly improve the accuracy of nebulae classification and their physical parameters,we developed the MRS-N *** article presented in detail each data processing step of the MRS-N Pipeline,such as removing cosmic rays,merging single exposure,fitting sky light emission lines,wavelength recalibration,subtracting skylight,measuring nebular parameters,creating catalogs and packing ***,a description of the data products,including nebular spectra files and parameter catalogs,is provided.

关键词： surveys catalogs methods:data analysis ISM:general

Microwave diagnostics of magnetic field strengths in solar flaring loops

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Science China(Technological sciences) 2021年第1期64卷 169-178页

作者： ZHU Rui TAN Baolin SU YingNa TIAN hui XU Yu CHEN XingYao SONG Yongliang TAN GuangYu School of Earth and Space sciences Peking UniversityBeijing 100871China Key Laboratory of Solar Activity National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100012China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210008China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China School of Astronomy and Space Science Nanjing UniversityNanjing 210023China

We have performed microwave diagnostics of the magnetic field strengths in solar flaring loops based on the theory of gyrosynchrotron *** Nobeyama Radioheliograph observations of three flare events at 17 and 34 GHz,we obtained the degree of circular polarization and the spectral index of microwave flux density,which were then used to map the magnetic field strengths in post-flare *** results show that the magnetic field strength typically decreases from ~800 G near the loop footpoints to~100 G at a height of 10-25 *** of our results with magnetic field modeling using a flux rope insertion method is also *** study demonstrates the potential of microwave imaging observations,even at only two frequencies,in diagnosing the coronal magnetic field of flaring regions.

关键词： solar magnetic field solar flare microwave observation gyrosynchrotron emission

On the Red Edge of the δ Scuti Instability Strip

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chinese Journal of Astronomy and Astrophysics 2002年第5期2卷 441-448页

作者： Yan Xu Zhi-Ping li li-Cai Deng Da-Run Xiong national astronomical observatories Chinese Academy of SciencesBeijing 100012 Department of Physics Tianjin Normal UniversityTianjin 300073 purple mountain observatory Chinese Academy of SciencesNanjing 210008

The δ Scuti star catalogue is used to derive the observational locations of such stars on the HR diagram. The theoretical and observational instability strips are compared to check the theoretical red edge obtained by considering nonlocal time-dependent convection theory. The observational instability strip almost overlaps with the theoretical one, but the observed blue and red envelopes are hotter than the theoretical edges. The distribution of δ Scuti stars in the pulsation strip is not uniform.

关键词： stars: variables: δ Sct - stars: oscillations ?stars: HR diagram

Data reduction and calibration of the FMG onboard ASO-S

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Research in Astronomy and Astrophysics 2019年第11期19卷 63-78页

作者： Jiang-Tao Su Xian-Yong Bai Jie Chen Jing-Jing Guo Suo liu Xiao-Fan Wang Hai-Qing Xu Xiao Yang Yong-liang Song Yuan-Yong Deng Kai-Fan Ji Lei Deng Yu Huang hui li Wei-Qun Gan Key Laboratory of Solar Activity National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space sciences University of Chinese Academy of SciencesBeijing 100049China Yunnan observatories Chinese Academy of SciencesKunming 650216China Innovation academy for Microsatellites of chinese academy of sciences Shanghai 201203China Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210008China

The Full-disk vector Magneto Graph(FMG)instrument will carry out polarization observations at one wavelength position of the Fe I 5324.179?spectral *** paper describes how to choose this single wavelength position,the relevant data-processing and the magnetic field calibrations based on the measured polarization signals at one single wavelength *** is found that solar radial Doppler velocity,which can cause the spectral line to shift,is a disadvantageous factor for the linear calibration at one wavelength *** at two symmetric wavelength positions may significantly reduce the wavelength shift effect(~75%),but simulations show that such polarization signals located at the solar limbs(e.g.,beyond the longitude range of±30°)are not free from the effect *** future work,we plan to apply machine learning techniques to calibrate vector magnetic fields,or employ full Stokes parameter profile inversion techniques to obtain accurate vector magnetic fields,in order to complement the linear calibration at the single wavelength position.

关键词： Sun photosphere-Sun magnetic fields-Sun calibration

LAMOST MRS-N Observation of the W80 Region

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Research in Astronomy and Astrophysics 2022年第7期22卷 161-175页

作者： Yao li Chao-Jian Wu Yong-Qiang Yao Wei Zhang Jia Yin Juan-Juan Ren Chih-Hao Hsia Rui Zhuang Jian-Jun Chen Yu-Zhong Wu hui Zhu Bin li Yong-hui Hou Meng-Yuan Yao Hong Wu national astronomical observatories Chinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China CAS Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China CAS Key Laboratory of Space Astronomy and Technology National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China State Key Laboratory of Lunar and Planetary sciences Macao University of Science and TechnologyTaipaMacaoChina University of Science and Technology beijing Beijing 100083China purple mountain observatory Chinese Academy of SciencesNanjing 210008China University of Science and Technology of China Hefei 230026China nanjing Institute of astronomical Optics&Technology National Astronomical ObservatoriesChinese Academy of SciencesNanjing 210042China China academy of Aerospace Electronics Technology Beijing 100094China

The spectral observations and analysis for the W80 region are presented by using the data of Medium-Resolution Spectroscopic Survey of Nebulae(MRS-N) with the Large Sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST).A total of 2982 high-quality nebular spectra have been obtained in the 20 square degree field of view which covers the W80 complex,and the largest sample of spectral data has been established for the first *** relative intensities,radial velocities(RVs),and full widths at half maximum(FWHMs) are measured with the high spectral resolution of LAMOST MRS-N,for Ha λ6563?,[NⅡ] λλ6548 A,6584 A,and [SⅡ] λλ6716A,6731 A emission *** the field of view of the whole W80 region,the strongest line emissions are found to be consistent with the bright nebulae NGC 7000,IC 5070,and LBN 391,and weak line emissions also exist in the Middle Region,where no bright nebulae are detected by the wide-band optical *** large-scale spectral observations of the W80 region reveal the systematic spatial variations of RVs and FWHMs,and several unique structural features.A "curved feature" to the east of NGC 7000,and a "jet feature" to the west of LBN 391 are detected to be showing larger RVs.A "wider FWHM region" is identified in the eastern part of NGC *** variations of[S Ⅱ]/Ha ratios display a gradient from southwest to northeast in the NGC 7000 region,and manifest a ring shape around the "W80 bubble" ionized by an O-type star in *** spectral and multi-band observations are guaranteed to investigate in detail the structural features.

关键词： surveys (ISM:)HII regions ISM:molecules ISM:bubbles methods:statistical