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On the Lower Energy Cutoff of Nonthermal Electrons in Solar Flares

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Chinese Journal of Astronomy and Astrophysics 2001年第5期1卷 453-459页

作者： Wei－QunGan You－PingLi 等 purplemountainobservatory ChineseAcademyofSciencesNanjing210008 NationalAstronomicalObservatories Ch

A quantitative method to determine the lower energy cutoff (Ec) of power-law electron beams is established. We apply this method to the 54 hard X-ray events observed with BATSE/Compton Gamma Ray observatory (CGRO). The results show that about 75% of the observed broken double power-law spectra of hard X-rays can be explained by a lower energy cutoff in the power-law electron beams. The values of Ec, varying among the flares, are all greater than the usually accepted 20 keV! On average, E~ is about 69 keV. So high a lower energy cutoff of nonthermal electrons implies that nonthermal electrons might not be as important in powering solar flares as was previously thought. Further significance of this finding is discussed.

关键词： Sun: hard X-rays - Sun: gamma-rays - Sun: flares - Sun: particles TheSun

Small Explorer for Solar Eruptions（SMESE）

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Small Explorer for Solar Eruptions（SMESE）

Space high energy gamma-ray and electron observation

第六届中日微重力科学专题研讨会

作者： Gan Weiqun chang jin purple mountain observatory CAS Nanjing 210008 P. R. China

＜正＞SMESE （SMall Explorer for Solar Eruptions） is a China-France joint solar mission. It will be launched around next solar maximum. Sun synchronous polar circular orbit will be adopted with an orbit altitude of 750 km, mission life is designed to be above 3 years. This mission aims at the observing flares and and Coronal Mass Ejections （CME） for the next solar maximum through a large wavelength coverage, ranging from the gamma rays to the far-infrared. It is of prime interest for the new developing activity known as Space Weather. The

关键词： solar Eruptions Explorer China-France joint mission

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Space high energy gamma-ray and electron observation

Recent Progresses of the DAMPE Mission

第六届中日微重力科学专题研讨会

作者： chang jin and Zhang Renjian purple mountain observatory CAS Nanjing 210008 P. R. China

＜正＞Cosmic ray electron （including positron） observations have been carried out by many different instruments during the last 40 years. Because of their low intensity （below 0.01 of the proton flux）, the accuracy of the energy spectrum is still not suffficient. At high energy （above hundreds of GeV）, only Emulsion Chamber （EC）

关键词： cosmic electron gamma-ray space observation

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空间科学学报 2024年第4期44卷 633-642页

作者： chang jin Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210033 School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026

The DArk Matter Particle Explorer(DAMPE)is a space high-energy particle andγ-ray detector whose major scientific goals are the indirect detection of dark matter particles,the origin of cosmic rays and highenergyγ-ray *** its successful launch in December 2015,the DAMPE has been operated smoothly in orbit for more than 8 *** direct measurements of the boron-to-carbon and boron-to-oxygen flux ratios,and the proton+Helium spectrum up to 316 TeV have been obtained,revealing new spectral features with very high *** search results ofγ-ray spectral line and fractionally charged particles indicate a good potential of DAMPE for indirect dark matter detection and new physical discovery in *** DAMPE measurements are expected to significantly advance our understanding of the fundamental problems in astroparticle physics.

关键词： DAMPE Dark matter Indirect detection Cosmic rays

The investigation of the Neupert effect in two solar flares

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Science China(Physics,Mechanics & Astronomy) 2009年第11期52卷 1686-1690页

作者： NING ZongJun purple mountain observatory, Nanjing 210008, China purple mountain observatory Nanjing 210008 China

The Neupert effect suggests a flare model in which the nonthermal emissions are produced by energetic electrons which heat lower corona and chromosphere to produce the thermal emissions. Based on this concept, we investigate the Neupert effect to test the correlation between the hard X-ray spectral index and the time rate of the UV flare area at 1600 or 171 . Using the T RACE and RHESSI observations, we explore these quantities for two solar flares, one on March 14, 2002 and the other on November 1, 2003. The negative dependence between the spectral index and the time rate of the UV flare area is found, especially during the hard X-ray sub-peaks. This finding indicates that the electron-beam-driven heating plays a prominent role in the UV emission of these two flares.

关键词： solar flares UV radiation X-rays

The simulation of GCRs at near earth interplanetary locations for radioprotection

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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

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

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.

THEORETICA　LCALCULATION　OF　ATOMIC　AND　MOLECULAR　DATA

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原子与分子物理学报 1997年第2期 35-37页

作者： Pei Chunchuan purple mountain observatory Academia Sinica Nanjing 210008

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关键词： Atomic and molecular data Interstellar molecules Equation of state Molecular lines observation