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Inhomogeneity in Spectral Transmission of the Coated UB VRI Filters of BFOSC and its Influence on Photometry

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chinese Journal of Astronomy and Astrophysics 2002年第6期2卷 563-575页

作者： Bao-An Yao and Liu Huang1 shanghai astronomical {2., chinese academy of sciences, shanghai 2000302.National astronomical Observatories, chinese academy of sciences, Beijing 100012 National astronomical Observatories Chinese Academy of Sciences Beijing 100012

In order to realize the Johnson UBV and Kron-Cousins RI photometric systems in BFOSC, glass filters were purchased according to the Bessell prescription. All the filters are anti-reflection coated,on both sides to increase the transmission. By comparing two dome flat-field exposures taken through any one of these filters set in two orientations 90degrees apart, inhomogeneities in the filter transmission is clearly demonstrated. Using a PDS microphotometer, we have confirmed that the form of their spectral transmission curve varied from point to point on the filters. This kind of inhomogeneity cannot be eliminated by dividing by flat-fielding exposure and must be ascribed to inhomogeneities in the coating. This is not some accidental defect in coating, it is in the existing coating technique because all the filters (including the narrow-band interference ones) for the BFOSC and a Hbeta filter made by another manufacturer showed a similar pattern. We found that for the studies of variable stars with amplitudes less than 0.05 mag. or studies aiming at establishing accurate C-M diagrams of star clusters, the usual uncoated Schott glass filters of Bessell's prescription are to be preferred.

关键词： methods : data analysis techniques : photometric

Synchrotron peak luminosity,black hole mass and Eddington ratio for SDSS flat-spectrum radio quasars

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Science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 202-206页

作者： GU MinFeng1 & CHEN ZhaoYu1,2.1 Key Laboratory for Research in Galaxies and Cosmology,shanghai astronomical {2.,chinese academy of sciences,shanghai 200030,china 2.Graduate University of the chinese academy of sciences,Beijing 100049,china 1. Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China 2. Graduate University of the chinese academy of sciences Beijing 100049 China

For a sample of 185 flat-spectrum radio quasars(FSRQs) constructed from the SDSS DR3 quasar catalog,we found a significant correlation between the synchrotron peak luminosity and both the black hole mass and Eddington *** implies that the physics of its jet formation is not only tightly related with the black hole mass,but also with the accretion *** verify that the synchrotron peak luminosity can be a better indicator of jet emission than 5 GHz luminosity,through comparing the relationships between each of these two parameters and both black hole mass and Eddington *** fundamental plane of black hole activity for our FSRQs is established as Lr ∝ L0x.80 ± 0.06 Mbh -0.04 ± 0.09 with a weak dependence on black hole mass,however,the scatter is significant.

关键词： black hole physics galaxies:active galaxies:nuclei quasars:emission lines quasars:general

An H_2. flare in GGD2.

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chinese Science Bulletin 2001年第1期46卷 35-39页

作者： XU Ye, ZHENG Xingwu JIANG Dongrong, ZHANG Fujun& YU Zhiyao1. shanghai astronomical {2., chinese academy of sciences, shanghai 200030, china 2. chinese National Observatories, chinese academy of sciences, Beijing 100080, china 3. Department of Astronomy, Nanjing University, Nanjing 2.0093, china shanghai astronomical {2. Chinese Academy of Sciences Shanghai China chinese National Observatories Chinese Academy of Sciences Beijing China Department of Astronomy Nanjing University 210093 China

We report the observing results of a short time scale monitoring of the 2. GHz water maser emission in GGD2.. A rapid water maser outburst with the time scales of 4 d has been detected, and the variations are accompanied by some changes in the line width. The time variations were probably caused by a collision pump which led to changes in the pump input.

关键词： interstellar masers (ISM) individual GGD2. masers.

Numerical simulation of hot accretion flows with thermal conduction

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Science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 168-172页

作者： WU MaoChun,YUAN Feng & BU DeFu Key Laboratory for Research in Galaxies and Cosmology,shanghai astronomical {2.,chinese academy of sciences,shanghai 200030,china 1. Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China

We report on the effects of isotropic thermal conduction in non-radiative collisionless accretion flows in two *** comparison to accretion flows without conduction,we find that the disk generally becomes cooler and ***,the magnitude of this effect depends on the kinetic viscosity *** it is proportional to density,the density profile of the accretion flow is flat,therefore the effect is not very ***,if it is proportional to r1/2.as is usual for the "α" disk description,the density profile is ***,the effect will be much more obvious,with the temperature profile of the accretion flow becoming much *** will have important observational consequences.

关键词： black hole accretion disk thermal conduction

Orbit determination and prediction accuracy analysis for a regional tracking network

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Science china(Physics,Mechanics & Astronomy) 2010年第6期53卷 1130-1138页

作者： ZHOU ShanShi 1,2.3 ,HU XiaoGong 1 & WU Bin 1 1 shanghai astronomical {2.,chinese academy of sciences,shanghai 200030,china 2.Graduate University of chinese academy of sciences,Beijing 100049,china 3 Research Center of GNSS,Wuhan 430079,china 1. shanghai astronomical {2. Chinese Academy of Sciences Shanghai 200030 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Research Center of GNSS Wuhan 430079 China

china's COMPASS satellite navigation system relies on a regional tracking network to provide navigation services. Limited by its geographic border,the regional network is able to cover only 30% of the medium-earth-orbits(MEO). Accuracy of determined and predicted orbits is not able to satisfy system requirements if the tracking data processing strategy for global tracking network processing is used for the regional network. Two major error sources for orbital prediction are accuracy of initial orbital elements and dynamical modeling. To achieve better prediction accuracy,we propose a two-step orbit determination and prediction strategy. For step 1,only solar radiation pressure(SRP) parameters are estimated along with the orbital elements and other parameters; for step 2.all parameters are estimated but the SRP parameters are tightly constrained to their step 1 estimates. Experimenting with data from a regional GPS network,we conclude for orbital prediction using the proposed two-step strategy,the average user range error(URE) for 2.-h prediction arcs is better than 0.6 m.

关键词： orbit determination and prediction regional tracking network URE

Intraplate Deformation of Asia Derived fromITRF2.00 Velocity Field

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Journal of china University of Geosciences 2002年第1期13卷 14-19页

作者： Jin Shuanggen Zhu Wenyaoshanghai astronomical {2. , chinese academy of sciences , shanghai 200030 shanghai astronomical {2. Chinese Academy of Sciences Shanghai 200030

The definition of an 'intraplate fixed' frame remains a significant error source for crustal motion studies at a few millimeters per year level. An appropriate implementation of such a frame is very important to avoid biased velocities and to confirm a valid geophysical interpretation. Here, we establish the newest global plate motion model of ITRF2.00VEL and research the definition of an Asian-fixed frame in Asia using the ITRF2.00 velocity field. By X2.and F ratio tests, we find a subset site in Asia that satisfies a rigid cap rotation with residual velocities 2.00 sites that are consistent with known active tectonic feature. An important result of this study is the identification of internal deformation of the order of 1-2.mm/a in an area usually interpreted as 'stable' Asia. These results should be further checked as newer, denser and more accurate space geodetic data sets with longer observation time span, which become available for Asia.

关键词： intraplate deformation GPS ITRF2.00.

Time of impact of fragment P2.of comet SL 9 on Jupiter

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chinese Science Bulletin 1997年第5期42卷 396-398页

作者： ZHOU Hongnan,QIAN Bochen, HUANG Keliang and LI Qibin1. Department of Astronomy, Nanjing University, Nanjing 2.0093, china 2. shanghai {2., chinese academy of sciences, shanghai 200030, china 3. Physics Department, Nanjing Normal University, Nanjing 2.0097, china 4. Beijing astronomical {2., chinese academy of sciences, Beijing 100080, china Department of Astronomy Nanjing University Nanjing China shanghai observatory Chinese Academy of Sciences Shanghai China Physics Department Nanjing Normal University Nanjing China Beijing astronomical observatory Chinese Academy of Sciences Behijing China

FROM 1994-07-16 to 1994-07-2., 2. fragments of comet SL 9 impacted against Jupiter in succession. During the impact period the impact of fragments D, E, K, N, P2.and S was observed in china. We used a 1.56-m telescope with the CCD camera of shanghai {2. to monitor Jupiter and its Galilean Satellites, obtaining 1000 high-quality images at B, V, I wave bands. Our data on optical wave bands are rather complete and valuable in the world. Specially, we got some images of Jupiter, Io and Europa in the impact time of fragment P2.impacting against Jupiter. This will help us understand the precise time, position, depth and energy of the P2.s collision. In this note, we report the impact time of fragment P2.of comet SL 9 and Jupiter. Since the impact of comet SL 9 was expected to take place on the side of Jupiter

关键词： comet comet Shoemaker-Levy 9 impacting against Jupiter impact time.

Spectral states and state preference of galactic X-ray binaries

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Science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 147-149页

作者： YAN Zhen & YU WenFei shanghai astronomical {2.,shanghai 200030,china 1. shanghai astronomical {2. Shanghai 200030 China

Using observations in the past four years with the All Sky Monitor(ASM) onboard the Rossi X-ray Timing Explorer(RXTE) and the Burst Alert Telescope(BAT) onboard the Swift,we demonstrate that the hard state and the soft state are the primary spectral states in galactic black hole and neutron star X-ray *** addition,we show quantitatively the preference of the two spectral states for each of the 2. bright persistent sources.

关键词： X-ray binaries:black holes neutron stars

Determination of chinese mobile SLR sites'coordinates

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chinese Science Bulletin 2003年第21期48卷 2300-2302页

作者： FENG Chugang, CAI Wusan, ZHU Yuanlan & YANG Fumin shanghai astronomical {2., chinese academy of sciences Center for Astro-Geodynamical Research, chinese academy of sciences, shanghai 200030, china Correspondence should be addressed to Feng Chugang (e-mail: fcg@***) shanghai astronomical {2. Chinese Academy of Sciences Shanghai China Center for Astro-Geodynamical Research Chinese Academy of Sciences Shanghai China

The geocentric coordinates of three mobile sites including Fangshan in Beijing, Urumqi in the Xinjiang Uy-gur Autonomous Region and Lhasa in Tibet are determinedin the ITRF2.00 frame by means of both the global SLRdata and the mobile (SLR) data obtained by a mobile satel-lite laser ranging (SLR) apparatus from Aug. 2.00 to Dec.2.01. The results showed that the geometrical performance of chinese SLR network has been significantly improved.

关键词：中国卫星激光修正设备数据处理几何学