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Research in Astronomy and Astrophysics 2010年第6期10卷 533-540页

作者： Jing wang jian-Yan Wei national astronomical {2. Chinese Academy of Sciences Beijing 100012 China

The correlation between distant Gamma-Ray Bursts （GRBs） and foreground galaxy clusters is re-examined by using the well localized （with an accuracy down to a few arcsec） Swift/XRT GRBs. The galaxy clusters are compiled from both the X-ray selected ROSAT brightest cluster sample （BCS） and the BCS extension by requiring δ ≥ 0° and b ≥ 2.°. The Swift/XRT GRBs fulfilling the above selection criteria are cross-correlated with the clusters. Both Nearest-Neighbor analysis and the angular two-point cross-correlation function show that there is not enough evidence supporting the correlation between the GRBs and foreground clusters. We suggest that the non-correlation is probably related to the GRB number-flux relation slope.

关键词： gamma rays bursts -- galaxies clusters general -- methods statistical

How to estimate the effect of an intense meteor shower on human space activities

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Science china(Physics,Mechanics & Astronomy) 2009年第8期52卷 1161-1168页

作者： WU GuangJie national astronomical {2./Yunnan Observatory,chinese academy of sciences.Kunming 650011,china national astronomical {2./Yunnan Observatory Chinese Academy of Sciences Kunming 650011 China

In the present age,the potential threat to space projects coming from some intense meteor storms has been ***,the increasing activities of mankind in space for scientific,commercial and military purposes have led to an increase in safety-related problems about the satellites,space stations and *** new techniques for observing meteors and meteor showers have been ***,how to estimate even predict the effect of an intense meteor shower should be further *** initial definition about a meteor storm based on visual observations with a Zenithal Hourly Rate of over one thousand seems insufficient,since it only means a storm or burst of meteors in *** 2.06 the author suggested a synthetical index of the potential threats about intense activities of meteors;however,it is too complex to determine several *** this paper,the author suggests a Special True Number Flux Density(STNFD).Set a certain energy-limit,or a certain electric-charge-limit,and then calculate the number flux *** the comparison between two of the 10 strong meteor showers in recent years it is found that the important factor affecting the space flight security is not only the number of meteoroids,but also their velocities,their average energy and the population index *** show that Giacobinids,even June Bootids,should be one of the most hazardous meteor showers.

关键词： meteors meteorites and tektites spacecraft/atmosphere interactions observation and data reduction techniques

Pulsars in FIRST Observations

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chinese Journal of Astronomy and Astrophysics 2002年第2期2卷 146-150页

作者： Xiang-Hua Li and Jin-Lin Han national astronomical {2., chinese academy of sciences. Beijing 100012 national astronomical {2. Chinese Academy of Sciences Beijing 100012

We identify 16 pulsars from the Survey of Faint Images of the Radio Sky at Twenty-cm (FIRST) at 1.4 GHz. Their positions and total flux densities are extracted from the FIRST catalog. By comparing the source positions with those in the PSR catalog, we obtain better determined positions of PSR J102.+1001, J1518+4904, J1652.2.51, and proper motion upper limits of PSR J0751+1807, J1012.5307, and J1640+2.2.. The proper motions of the other ten pulsars are consistent with the catalog values.

关键词： pulsar: general -stars: neutron

A black hole preying on the star for a gamma-ray burst of GRB080503:Evidence for the second event in this new class

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Science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 117-119页

作者： LU Ye & GAO He national astronomical {2.,chinese academy of sciences.Beijing 100012.china 1. national astronomical {2. Chinese Academy of Sciences Beijing 100012 China

In this paper,we critically assess GRB080503,a short gamma-ray burst with very bright extended emission(about 30 times the gamma-ray fluence of the initial spike).The light curve of the prompt γ-ray emission of GRB080503 resembles that of GRB 060614 which has been suggested to be due to an event from an intermediate mass black hole(IMBH) preying on a *** therefore propose that GRB080503 is also due to a similar event;the mass of the IMBH is estimated to be about 4.6×104 solar masses,and the engulfed star had about the same mass and size as the *** also estimate that the total burst energy is about 7.67× 1050 ergs.

关键词： gamma rays:bursts GRB080503 GRB060614-type

A Possible X-ray Quasi-periodic Oscillation in the Narrow-line Seyfert 1 Galaxy Mrk 142

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Research in Astronomy and Astrophysics 2024年第6期24卷 191-200页

作者： Xiao-Gu Zhong jian-Cheng wang Yong-Yun Chen Xiao-{2. Yu College of Physics and Electronic Engineering Qujing Normal UniversityQujing 655011China Yunnan observatories Chinese Academy of SciencesKunming 650216China

A possible quasi-periodic oscillation(QPO) at frequency 7.045 × 10^(-5) Hz is found in the narrow-line Seyfert 1galaxy Mrk 142.in the data of XMM-Newton collected on 2.2. April *** find that the QPO signal is statistically significantly larger than the 5σ level and highly coherent with quality factor Q > 5 at the 0.3–10 keV band by using the method of the Lomb–Scargle Periodogram,the Weighted Wavelet Z-transform and the *** analyze the data in 0.3–0.6 keV,0.6–1 keV,1–3 keV and 3–10 keV energy bands,and find obvious QPO signals at 0.3–0.6 keV and 1–3 keV *** then analyze the time-average spectra and time variability at the QPO frequency of 7.045 × 10^(-5) Hz,and use a model to fit *** find that the QPO signal mainly comes from the X-ray hot corona.

关键词： X-rays:galaxies galaxies:Seyfert accretion accretion disks radiation mechanisms:general

Possible triggering of solar activity to big earthquakes (Ms ≥ 8) in faults with near west-east strike in china

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Science china(Physics,Mechanics & Astronomy) 2004年第2期47卷 173-181页

作者： HAN Yanben1, GUO Zengjian1,2. WU Jinbing1,2.& MA Lihua1 1. national {2. observatories, chinese academy of sciences. Beijing 100012, china 2. Earthquake Research Institute of Lanzhou, CSB, Lanzhou 73000, china Correspondence should be addressed to Han Yanben (email: hyb@***) 1. national astronomical {2. Chinese Academy of Sciences 100012 Beijing China 2. Earthquake Research Institute of Lanzhou CSB 73000 Lanzhou China

This paper studies the relationship between solar activity and big earthquakes (Ms≥8) that occurred in china and western Mongolia. It is discovered that the occurrence dates of most of the big earthquakes in and near faults with west-east strike are close to the maximum years of sunspot numbers, whereas dates of some big earthquakes which are not in such faults are not close to the maximum years. We consider that it is possibly because of the appearance of many magnetic storms in the maximum years of solar activity. The magnetic storms result in anomalies of geomagnetic field and then produce eddy current in the faults gestating earthquake with near west-east strike. Perhaps the gestated big earthquakes occur easily since the eddy current heats the rocks in the faults and therefore decreases the shear resistant intensity and the static friction limit of the rocks .

关键词： earthquake, solar activity, magnetic storm, eddy current.

Network analysis reveals context-dependent structural complexity of social calls in serrate-legged small treefrogs

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Current Zoology 2024年第2期70卷 253-261页

作者： Ke Deng Qiao-ling He Tong-Liang wang Ji-Chao wang jian-Guo Cui CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization&Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province Chengdu Institute of BiologyChinese Academy of SciencesChengdu 610041China University of chinese academy of Science Beijing 100049China Ministry of Education Key Laboratory for Ecology of Tropical lslands Key Laboratory of Tropical Animal and Plant Ecology of Hainan ProvinceCollege of Life SciencesHainan Normal UniversityHaikou 571158China

Vocal communication plays an important role in survival,reproduction,and animal social *** and mammals produce com-plex vocal sequence to convey context-dependent *** are conspicuous features of the behavior of most anuran species(frogs and toads),and males usually alter their calling strategies according to ecological context to improve the attractiveness/***,very few studies have focused on the variation of vocal sequence in *** the present study,we used both conventional method and network analysis to investigate the context-dependent vocal repertoire,vocal sequence,and call network structure in serrate-legged small treefrogs Kurixalus *** found that male *** modified their vocal sequence by switching to different call types and increasing repertoire size in the presence of a competitive ***,compared with before and after the playback of advertisement calls,males emited fewer advertisement calls,but more aggressive calls,encounter calls,and compound calls during the playback *** analysis revealed that the mean degree,mean closeness,and mean betweenness of the call networks significantly decreased during the playback period,which resulted in lower *** addition,the increased proportion of one-way motifs and average path length also indicated that the connectivity of the call network decreased in competitive ***,the vocal sequence of *** did not display a clear small-world network structure,regardless of *** study presents a paradigm to apply network analysis to vocal sequence in anurans and has important implications for understanding the evolution and function of sequence patterns.

关键词： call network centrality Kurixalus odontotarsus vocal repertoire vocal sequence.

Observational Accuracy of Sunrise and Sunset Times in the Sixth Century china

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chinese Journal of Astronomy and Astrophysics 2006年第5期6卷 629-634页

作者： Yong Li national astronomical {2. Chinese Academy of Sciences Beijing 100012

The Daye Calendar was compiled in AD 597 in the Sui Dynasty. We investigate the records of sunrise and sunset times on the 2. solar-term days in the calendar. By converting the ancient chinese time units, Chen, Ke and Fen to hour, minute and second, and carrying out a comparison between the ancient records and values computed with modem astronomical theory, we find that the accuracy of solar measurements in the Sui period is remarkably high： for sunrise times, the average absolute deviation is 3.63 min （this value can be further reduced to 3.03 min when erroneous data are excluded）, and for sunset times it is 3.48 min. We also find that the observed sunrise and sunset times are strictly symmetrically distributed with respect to both the Winter Solstice and the Summer Solstice, with their deviations showing a similar symmetrical distribution as well. We give a discussion on the date of observation, the feature of the data, and possible reasons of the deviation.

关键词： history of astronomy -- astrometry -- solar-terrestrial relations -- methods statistical

Evolution of the Level of Sunspot Activity in Solar Cycles I. Evolution in the Descending Phase

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chinese Journal of Astronomy and Astrophysics 2006年第3期6卷 354-362页

作者： Jia-Long wang national astronomical {2. Chinese Academy of Sciences Beijing 100012

Taking the 13-point smoothed monthly sunspot number,Ri, and the deviation of the 13 associated monthly sunspot numbers from the smoothed one, Di, as a number-pair describing the global level of sunspot activity, the evolution of the level is statistically studied for the period from the month which is just 48 months before the minimum to the minimum in the descending phase, using the observed data of Solar Cycles 10 to 2.. Our results show （1） for 46 months （94%） of the studied 49 months it is found that for a given month, the distribution of the 13 pairs which come from the 13 solar cycles on a log Ri - Di plane may be fitted by a straight line with a correlation coefficient larger than the critical one at confidence level a = 5%, and for 36 months （73%） the fitting is even better, for a = 1%; （2. time variations of these two parameters and their correlations in the studied period can be described respectively by functions of time, whose main trends may be expressed by a linear or simple curvilinear function; （3） the evolutionary path of the level of sunspot activity may be represented by a logarithmic function as log/~ = 0.704 lnDi - 0.2.1.

关键词： Sun - sunspots - active level evolution

Spectral Properties of Anomalous X-ray Pulsars

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chinese Journal of Astronomy and Astrophysics 2003年第6期3卷 543-550页

作者： Ye Lu, Wei wang and Yong-Heng Zhaonational {2. observatories, chinese academy of sciences. Beijing 100012 national astronomical {2. CAS NAOC Beijing 100012 China

We examine the spectra of the persistent emission from anomalous X-ray pulsars (AXPs) and their variation with the spin-down rate . Based on an accretion-powered model, the influences of both the magnetic field and the mass accretion rate on the spectral properties of AXPs are addressed. We then investigate the relation between the spectral property of AXPs and mass accretion rate . The result shows that there exists a linear correlation between the photon index and the mass accretion rate: the spectral hardness increases with increasing . A possible emission mechanism for the explanation of the spectral properties of AXPs is also discussed.

关键词： pulsars: general stars: neutron X-rays: stars accretion: accretion disks