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On the knee of Galactic cosmic rays in light of sub-TeV spectral hardenings

chinese Physics C 2018年第7期42卷 113-122页

作者： Yi-Qing Guo1 2 Qiang Yuan1 3.1. Key Laboratory of Dark Matter and Space Astronomy purple mountain observatory {3. academy of Sciences nanjing 210008 china 2. Key Laboratory of Particle Astrophysics Institute of High Energy Physics Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of Sciences Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of Sciences School of Astronomy and Space Science University of Science and Technology of China

More than fifty years after the discovery of the knee in the cosmic ray （CR） spectra, its physical origin remains a mystery. This is partly due to the ambiguity of the energy spectra of individual components. Recently, direct measurements from several space experiments found significant spectral hardenings of CR nuclei at ~200 GV. A joint modeling of the direct and indirect measurements may help to understand the experimental systematics and the physics of the knee. In this work, we update the phenomenological ＂poly-gonato＂ model to include the spectral hardenings, with a changing spectral index of γ ＋ β·logE. This modification gives a reasonable description of the CR spectra in a wide energy range. However, the fits to different data sets give different results. We find that the fit to the AMS-02 and CREAM data slightly favors a relatively low energy knee of the light components. In such a case, the expected all-particle spectra under-shoot the data, which may require an extra component of CRs. The fits to AMS-02 data and the light component （H＋He） data from the Tibet ASγ/ARGO-YBJ/WFCTA and KASCADE experiments give consistent results with the all-particle spectra. We further propose a possible physical realization of such a ＂modified poly-gonato＂ model of spectral hardenings by means of spatially-dependent diffusion of CRs. We find reasonably good agreement between the model predictions and the data for CR spectra, the secondary-to-primary ratios, and the amplitude of anisotropies.

关键词： cosmic ray knee spectrum propagation

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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 {3.

ＴＨＥＯＲＥＴＩＣＡＬＣＡＬＣＵＬＡＴＩＯＮＯＦＡＴＯＭＩＣＡＮＤＭＯＬＥＣＵＬＡＲＤＡＴＡＰｅｉＣｈｕｎｃｈｕａｎＰｕｒｐｌｅＭｏｕｎｔａｉｎＯｂｓｅｒｖａｔｏｒｙＡｃａｄｅｍｉａＳｉｎｉｃａＮａｎｊｉｎｇ２１０... 详细信息

ＴＨＥＯＲＥＴＩＣＡＬＣＡＬＣＵＬＡＴＩＯＮＯＦＡＴＯＭＩＣＡＮＤＭＯＬＥＣＵＬＡＲＤＡＴＡＰｅｉＣｈｕｎｃｈｕａｎＰｕｒｐｌｅＭｏｕｎｔａｉｎＯｂｓｅｒｖａｔｏｒｙＡｃａｄｅｍｉａＳｉｎｉｃａＮａｎｊｉｎｇ２１０００８ＡＢＳＴＲＡＣＴＢｙｕｓｉｎ...

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

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Electron surfing acceleration in a current sheet of flares

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Science china(Physics,Mechanics & Astronomy) 2009年第11期52卷 1810-1812页

作者： WANG DeYu1 & LU QuanMing2 1 purple mountain observatory, {3., china 2 School of Earth and Space Sciences, University of Science and Technology of china, Hefei 23.026, china purple mountain observatory Nanjing 210008 China School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China

A model of electron acceleration in a current sheet of flares is studied by the analytical approximation solution and the test particle simulation. The electron can be trapped in a potential of propagating electrostatic wave. The trapped electron moving with the phase velocity v p of wave may be effectively accelerated by ev p/c × B z force along the outflow direction in the current sheet, if a criterion condition K > 0 for electron surfing acceleration is satisfied. The electron will be accelerated continuously until the electron de-trap from the wave potential at the turning point S.

关键词： electron acceleration electrostatic wave current sheet

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Optical results of the black hole microquasar SS 43.

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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,{3. academy of Sciences,nanjing 210008,china 2 Graduate University of {3. 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 43. 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 43. 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

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A good example of high-energy radiation delay event

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chinese Science Bulletin 1997年第4期42卷 313-315页

作者： GAN Weiqun and Rieger Erich1 purple mountain observatory, {3., china 2. Max-Planck Institute of Extraterrestrial Physics, Garching 85740,Germany purple mountain observatory Nanjing China Max-Planck Institute of Extraterrestrial Physics Garching Germany

THE delay of high-energy radiation of solar flares can be divided into two types: one is the energy-dependent delay in the hard X-ray regime, the other is the delay between the hard X-rays and instantaneous γ-ray line (GRL) emissions. Both types have different physical meanings. The former reflects the difference in acceleration or transportation of energetic electrons with various energies, while the latter reflects such a difference between the energetic electrons

关键词： sun. flare X-ray γ-ray.

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An alternative evolution scenario for OAO 1657-415 and IGR J18483.03.1

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Science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 130-134页

作者： LIU QingZhong1,2,LI Hui1,3.& YAN JingZhi1,2 1 purple mountain observatory,{3. academy of Sciences,nanjing 210008,china 2 Service d’Astrophysique,CEA Saclay and University Paris Diderot,91191 Gif-sur-Yvette,France 3.Graduate University of {3. academy of Sciences,Beijing 100049,china 1. purple mountain observatory Chinese Academy of Sciences Nanjing 210008 China 2. Service d’Astrophysique CEA Saclay and University Paris Diderot 91191 Gif-sur-Yvette France 3. Graduate University of chinese academy of Sciences Beijing 100049 China

The relation between the spin period and the orbital period in high-mass X-ray binaries is ***/X-ray binaries and SG/X-ray binaries occupy different areas in Corbet's *** two SG/X-ray binaries,IGR J18483.03.1 and OAO 1657-415,however,appear to occupy a transition region between Be/X-ray binaries and wind-fed SG/X-ray *** can be understood by noting that the neutron stars in the two SG/X-ray binaries have not reached their equilibrium spin periods when the donors evolved off the main ***,we provide an alternative scenario to explain their location in Corbet's diagram:the SG/X-ray binaries are the descendants of Be/X-ray binaries,*** supergiants in these systems were formed from O-type emission line stars instead of normal main-sequence ***,we suggest that there are two types of SG/X-ray binaries:one is directly evolved from a normal OB-type main sequence and neutron star system without an X-ray history,and the other evolved from a Be/X-ray binary with an X-ray history.

关键词： high-mass X-ray binary pulsar Corbet’s diagram stellar evolution

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An Electron Density Model above the Sunspot from a Mapping of NOAA 7260 at 17 GHz

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chinese Journal of Astronomy and Astrophysics 2002年第3期2卷 287-292页

作者： Xing－FengYu Jin－XingYao NationalAstronomicalObservatories ChineseAcademyofSciencesBeijing100012 purplemountainobservatory ChineseAcademyofSciencesNanjing210008

The brightness temperature distribution of microwave emission in a solar active region generally shows a ring structure, with a dip at the centre. However, no dip was found in the Nobeyama Radioheliograph left handed circular polarization (LCP) image on 1992 August 18; instead, there was a peak. This is a completely LCP source with zero right-handed circular polarization (RCP). We examine this structure in terms of the joint effect of gyroresonance and bremsstrahlung mechanism with a raised electron density above the central part of the sunspot, and the commonly assumed temperature and vertical dipole magnetic field models. The raised electron density is found to be 1.4 × 1011 cm-3.at the chromosphere base.

关键词： Sun: activity - sunspots - Sun: radio radiation - Sun: chromosphere

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CO observations of massive star forming regions at different evolutionary phases

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Science china(Physics,Mechanics & Astronomy) 2006年第5期49卷 626-640页

作者： CHEN Xi1,2, XU Ye1,3. SHEN Zhiqiang1,3.& LI Jingjing1,2 1. Shanghai Astronomical observatory, chinese academy of Sciences, Shanghai 20003., {3. 2. Graduate School of the chinese academy of Sciences, Beijing 10003., {3. 3. Joint Institute for Galaxy and Cosmology, Shanghai Astronomical observatory and the University of Science and Technology of {3., Shanghai 20003., {3. Shanghai Astronomical observatory Chinese Academy of Sciences Shanghai 200030 China Graduate School of the chinese academy of Sciences Beijing 100034 China Joint Institute for Galaxy Cosmology Shanghai Astronomical Observatory the University of Science Technology of china Shanghai 200030 China

The 12CO (J=1-0), 13.O (J=1-0) and C18O (J=1-0) emissions in 9 massive star forming regions, which are believed to be at different stages of massive star formation, were mapped with the 13.7 m millimeter wave telescope at Qinghai Station of purple mountain observatory. Of the observed 9 sources, 13.O cores were detected in seven of them, and C18O cores in five of them. And only two sources associated with C18O cores and H2O masers showed the extended structures and strong outflows. This is the first detection of outflow associated with IRAS 22566+5828 in the observing field of S152/S153. The physical parameters of cores and outflows for these sources, derived from Local Thermal Equilibrium (LTE) analysis, are presented. These observing results suggest that the C18O cores will only appear when the gas density is high enough and the probability to have an outflow is very high when the clumps show the C18O and H2O maser simulta- neously.

关键词： star formation cloud core outflow H2O maser

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^(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,13.O and C18O J=1-0 emission in 11 nearby（cz1000 km s-1） bright infrared *** 12CO and 13.O are detected in the centers of all the galaxies,except for 13.O in NGC 3.3.. 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 3.27,NGC 3.28,NGC 463. and *** radial distributions of 12CO and 13.O in NGC 3.27,NGC 3.28 and M51 can be well fitted by an exponential profile. The 12CO/13.O 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 13.O/C18O,13.O/HCO＋and 13.O/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

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On the Evolution of the Lower Energy Cutoff of Nonthermal Electrons in Solar Flares

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chinese Journal of Astronomy and Astrophysics 2002年第2期2卷 103-105页

作者： Wei－QunGan You－PingLi 等 purplemountainobservatory ChineseAcademyofSciencesNanjing210008 NationalAstronomicalObservatories ChineseAcademyofSciencesBeijing100012

Using the method recently developed by Can et al. (2001a, 2002), We investigate the time variation of the lower energy cutoff (Ec) of nonthermal electrons for three BATSE/CGRO hard X-ray events. The result shows that Ec changes with time, from smaller before the peak flux, to larger at the peak, and then back to smaller after the peak. Such a variation of Ec, being a preliminary conclusion for the first time, should be checked in the future by using data with a higher energy resolution.

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

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