Multicolor photometric study of M31 globular clusters  

作　　者：Zhou Fan Jun Ma Xu Zhou 

机构地区：[1]National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, China [2]Graduate University of Chinese Academy of Sciences, Beijing 100049, China

出　　处：《Research in Astronomy and Astrophysics》2009年第9期993-1010,共18页天文和天体物理学研究（英文版）

基　　金：Supported by the National Natural Science Foundation of China (Grant Nos.10873016,10803007,10473012,10573020,10633020,10673012 and 10603006);Supported by the National Basic Research Program of China (973 Program,No.2007CB815403)

摘　　要：We present the photometry of 30 globular clusters （GCs） and GC candidates in 15 intermediate-band filters covering the wavelength region from - 3000 to 10000A using the archival CCD images of M31 observed as part of the Beijing - Arizona - Taiwan - Connecticut （BATC） Multicolor Sky Survey. We transform these intermediate-band photometric data into the photometry in the standard U BV RI broadbands. These M31 GC candidates are selected from the Revised Bologna Catalog （RBC V.3.5）, and most of these candidates do not have any photometric data. Therefore, the presented photometric data are a supplement to the RBC V.3.5. We find that 4 out of 61 GCs and GC candidates in RBC V.3.5 do not show any signal on the BATC images at their locations. By applying a linear fit of the distribution in the color-magnitude diagram of blue GCs and GC candidates using data from the RBC V.3.5, in this study, we find the ＂blue-tilt＂ of blue M31 GCs with a high confidence at 99.95% or 3.47cr for the confirmed GCs, and 〉 99.99% or 4.87e for GCs and GC candidates.We present the photometry of 30 globular clusters （GCs） and GC candidates in 15 intermediate-band filters covering the wavelength region from - 3000 to 10000A using the archival CCD images of M31 observed as part of the Beijing - Arizona - Taiwan - Connecticut （BATC） Multicolor Sky Survey. We transform these intermediate-band photometric data into the photometry in the standard U BV RI broadbands. These M31 GC candidates are selected from the Revised Bologna Catalog （RBC V.3.5）, and most of these candidates do not have any photometric data. Therefore, the presented photometric data are a supplement to the RBC V.3.5. We find that 4 out of 61 GCs and GC candidates in RBC V.3.5 do not show any signal on the BATC images at their locations. By applying a linear fit of the distribution in the color-magnitude diagram of blue GCs and GC candidates using data from the RBC V.3.5, in this study, we find the ＂blue-tilt＂ of blue M31 GCs with a high confidence at 99.95% or 3.47cr for the confirmed GCs, and 〉 99.99% or 4.87e for GCs and GC candidates.

关 键 词：galaxies： individual （M31） - galaxies： star clusters - galaxies： evolution 

分 类 号：TN911.73[电子电信—通信与信息系统] P158[电子电信—信息与通信工程]