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Diffuse interstellar absorption bands

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Science china(Physics,Mechanics & Astronomy) 2009年第4期52卷 489-501页

作者： XIANG FuYuan1,2,LIANG ShunLin2 & LI AiGen2,3 1 Faculty of Materials,Photoelectronics and Physics,Xiangtan University,Xiangtan 411105,china 2 Department of Physics and Astronomy,University of Missouri,Columbia,MO 65211,USA 3 purple mountain observatory,chinese academy of sciences,nanjing 210008,china 1. Faculty of Materials Photoelectronics and Physics Xiangtan University Xiangtan 411105 China 2. Department of Physics and Astronomy University of Missouri Columbia MO 65211 USA 3. purple mountain observatory Chinese Academy of Sciences Nanjing 210008 China

The diffuse interstellar bands(DIBs) are a large number of absorption bands that are superposed on the interstellar extinction curve and are of interstellar origin. Since the discovery of the first two DIBs in the 1920s,the exact nature of DIBs still remains unclear. This article reviews the history of the detections of DIBs in the Milky Way and external galaxies,the major observational characteristics of DIBs,the correlations or anti-correlations among DIBs or between DIBs and other interstellar features(e.g. the prominent 2175 Angstrom extinction bump and the far-ultraviolet extinction rise),and the proposed candidate carriers. Whether they are also present in circumstellar environments is also discussed.

关键词： astrophysics interstellar matter interstellar extinction diffuse interstellar band circumstellar environment

Optical results of the black hole microquasar SS 433

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Science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 153-156页

作者： LI Hui1,2 & YAN JingZhi1,3 1 purple mountain observatory,chinese academy of sciences,nanjing 210008,china 2 Graduate University of chinese academy of sciences,Beijing 100049,china 3 Service d’Astrophysique,CEA Saclay and University Paris Diderot,91191 Gif-sur-Yvette,France 1. purple mountain observatory Chinese Academy of Sciences Nanjing 210008 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Service d’Astrophysique CEA Saclay and University Paris Diderot 91191 Gif-sur-Yvette France

We present optical spectroscopic observations of SS 433 during different precessional and orbital *** 2004,2007 and 2008 data provide us a good chance to study the variability of the Hα line at different orbital phases for nearly the same disk *** data show that the Hα of SS 433 usually had a symmetric profile between orbital phases 0.25-0.75,while an asymmetric structure with a strong red peak was observed for other orbital *** suggest that the orbital variability of Hα emission is connected with accretion flow from the donor star to the accretion *** addition,we attribute the dramatic increase of Hα emission during our 2007 observational run,which had a time scale of one day,to the emergence of strong jets.

关键词： high-mass X-ray binary black hole spectroscopy outflow wind relativistic jet

^(12)CO,^(13)CO and C^(18)O observations along the major axes of nearby bright infrared galaxies

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Research in Astronomy and Astrophysics 2011年第7期11卷 787-810页

作者： Qing-Hua Tan Yu Gao Zhi-Yu Zhang Xiao-Yang Xia purple mountain observatory Chinese Academy of Sciences Nanjing 210008 China Graduate School of chinese academy of sciences Beijing 100039 China Tianjin Astrophysics Center Tianjin Normal University Tianjin 300384 China

We present simultaneous observations of 12CO,13CO and C18O J=1-0 emission in 11 nearby（cz1000 km s-1） bright infrared *** 12CO and 13CO are detected in the centers of all the galaxies,except for 13CO in NGC 3031. We have also detected C18O,CSJ=2-1 and HCO＋J=1-0 emission in the nuclear regions of M82 and *** are the first systematical extragalactic detections of 12CO and its isotopes from the PMO 14 m *** have conducted half-beam-spaced mapping of M82 over an area of 4×2.5 and major axis mapping of NGC 3627,NGC 3628,NGC 4631 and *** radial distributions of 12CO and 13CO in NGC 3627,NGC 3628 and M51 can be well fitted by an exponential profile. The 12CO/13CO intensity ratio,R,decreases monotonically with the galactocentric radius in all mapped *** average R in the center and disk of the galaxies are 9.9±3.0 and 5.6±1.9,respectively,much lower than the peculiar R（～24） found in the center of *** intensity ratios of 13CO/C18O,13CO/HCO＋and 13CO/CS（either our or literature data） show little variation with galactocentric radius,in sharp contrast with the greatly varied *** supports the notion that the observed gradient in R could be the result of the variations of the physical conditions across the *** H2 column density derived from C18O shows that the Galactic standard conversion factor（X-factor） overestimates the amount of the molecular gas in M82 by a factor of～*** observations suggest that the X-factor in active star-forming regions（i.e.,nuclear regions） should be lower than that in normal star-forming disks and the gradient in R can be used to trace the variations of the X-factor.

关键词： galaxies:ISM—ISM:clouds—ISM:molecules—radio lines:ISM

A Large-Scale Survey for Extremely Cold Young Stellar Objects in the Galaxy

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天文研究与技术 1999年第S1期 166-174页

作者： Yang Ji 1,2 ,Jiang Zhibo 1,2 ,Wang Min 1,2 ,Wang Hongchi 1,2 ,Hiroshi Kimura 1,3 1(purple mountain observatory, The chinese academy of sciences, nanjing 210008, china) 2(National Astronomical Observatories, The chinese academy of

We conducted a large-scale survey of the extremely-cold infrared sources(ECISs) along the Galactic plane. There are 1912 (IRAS) sources selected on the basis of their color indices and their association with recent star formation. A quick survey was made toward 724 sources. There are 251 sources detected with significant CO emission during the quick survey above the detection limit of 0 9 K. Among the various sources detected, there are 147 sources found to have broad CO wing emission, including 116 newly detected sources. These sources comprise a new database for future study of star formation in our Galaxy. Using the known outflow sources as an effective indicator, we found the outflow detection rate of the quick survey is 62%, reasonably sensitive in survey for new outflow sources. Results from limited follow-up studies are introduced.

关键词： Stellar Objects in the Galaxy A Large-Scale Survey for Extremely Cold Young

Energy Spectrum of Interplanetary Coronal Mass Ejections

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Energy Spectrum of Interplanetary Coronal Mass Ejections

The simulation of GCRs at near earth interplanetary locations for radioprotection

第十二届全国日地空间物理学术讨论会

作者： D.J.Wu~1 H.Q.Feng~2 J.K.Chao~3 (1 purple mountain observatory,chinese academy of sciences,nanjing 210008,china) (2 Department of Physics and Electron Science,Luoyang Normal University,Luoyang 471022.china) (3 Institute of Space Science,National Central University,Chungli 32001,Taiwan)

＜正＞Recent observations of the solar wind show that interplanetary magnetic flux ropes （IMFRs）,as an important subset of interplanetary coronal mass ejections （ICMEs）,have a continuous scale-distribution in both size and energy from small-scale flux ropes （～0.01 AU） to large-scale magnetic clouds （～0.25 AU） [1,2,3].In this letter,based on the observations of IMFRs the energy spectrum of ICMEs is presented as a

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来源： cnki会议评论

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Science china(Physics,Mechanics & Astronomy) 2010年第9期53卷 1739-1745页

作者： BAO Gang purple mountain observatory,chinese academy of sciences,nanjing 210008,china 1. purple mountain observatory Chinese Academy of Sciences Nanjing 210008 China

The interplanetary radiation environment is detrimental to space missions,giving rise to cumulative damage to both astronauts and payloads and enhanced background levels in ***,there is a pressing need for a reliable simulation of these harmful effects for risk assessment and shielding optimization in manned space *** have modeled the interaction processes of the two most abundant galactic cosmic ray particle fluxes(protons and helium nuclei) using the Geant4 toolkit for a given space vehicle *** total energy deposited due to protons and helium nuclei is calculated in this work,and the energy deposited due to the secondary particles generated by this radiation is also estimated.

关键词： radioprotection simulation Geant4 cosmic rays

Diagnostics of magnetic field strength for gyrosynchrotron radiation regions of the lower harmonics

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chinese Science Bulletin 1998年第14期43卷 1183-1187页

作者： ZHOU Aihua purple mountain observatory, chinese academy of sciences, nanjing 210008, china purple mountain observatory Chinese Academy of Sciences Nanjing China

A diagnostic formula of magnetic field strength of gyrosynchrotron radiation regions of the lower harmonics (5 ≤S≤10 ) is presented based on their emissivity η νBN , absorptivity κ νBN , and the turnover frequency of radio spectra ν P. Their diagnostic error is estimated. And an accurate relation between electron energy spectral index δ and brightness temperature spectral index β is also given.

关键词： lower harmonic radio emission magnetic field.

Near-Infrared Observations of the Massive Star Forming Region IRAS 23151+5912

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chinese Journal of Astronomy and Astrophysics 2004年第3期4卷 284-298页

作者： Xue-Peng Chen Yong-Qiang Yao purple mountain observatory chinese academy of sciences, nanjing 210008 purple mountain observatory Chinese Academy of Sciences Nanjing 210008

Near-infrared images and K-band spectroscopy of the massive star-formingregion IRAS 23151+5912 are presented. The JHK′ images reveal an embedded infrared clusterassociated with infrared nebula, and the H_2 (2.12 μm) narrowband image provides for the first timeevidence of outflow activity associated with the cluster. That the cluster is young can be shown bythe high percentage of infrared excess sources and the outflow activity. We suggest an age of thecluster of ～ 10~6 yr. Eight young stars are found in the bright nebular core around IRAS23151+5912. By the color-magnitude diagrams of the cluster, we found five high-mass YSOs and fourintermediate-mass YSOs in the cluster. Eight H_2 emission features are discovered in the region witha scattered and non-axisymmetric distribution, indicating the existence of multiple outflows drivenby the cluster. Diffuse H_2 emission detected to the north and to the west of the cluster mayresult from UV leakage of the cluster. Brγ, H_2, and CIV emission lines are found in the K-bandspectrum of the brightest source, NIRS 19, indicating the presence of envelope, stellar wind, andshock in the circumstellar environment. We have estimated an O7-O9 spectral type for the centralmassive YSO (20 ～ 30 solar mass), with an age of less than 1 x 10~6 yr.

关键词： infrared radiation stars: formation ISM: individual: IRAS 23151 + 5912 ISM: jets and outflows

Projection Effects on Physical Parameters Obtained from Solar Vector Magnetograms

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chinese Journal of Astronomy and Astrophysics 2002年第2期2卷 174-182页

作者： Hui Li purple mountain observatory, chinese academy of sciences, nanjing 210008 National Astronomical Observatories, chinese academy of sciences, Beijing 100012 purple mountain observatory Chinese Academy of Sciences Nanjing 210008 []National Astronomical Observatories Chinese Academy of Sciences Beijing 100012

Projection effects in Huairou solar vector magnetograms are corrected by transferring or mapping the observed vector magnetogram in the image plane to the heliographic plane (planar correction) and to the heliospheric coordinate system (spherical correction). The magnetograms after the correction are considerably dif- ferent. The planar correction and the spherical correction lead to slightly different magnetic configurations, especially when the active region involved is far from the disk center. We also discuss the effects of the corrections on magnetic activity pa- rameters, such as magnetic shear, current helicity, etc. It is shown that the neutral line is obviously distorted after the mapping. The mapping generally decreases the average shear angle on the neutral line by several degrees when the active region is in the eastern hemisphere, and increases it when in the western hemisphere. In most of the cases studied, the correction reduces the current helicity imbalance, and sometimes even changes its sign. It is found that the current helicity imbalance may change its sign in its evolution when there are apparent fluxes emerging from the lower photosphere. The corrections increase the noise level of Bz greatly, and decrease the noise level of B~ slightly. The accuracy of the magnetic field measure- ment at Huairou is estimated to be better than 20 G and 150 G for the longitudinal and the transverse component, respectively.

关键词： Sun: magnetic fields ─Sun: activity ─Sun: photosphere