Resolved objects in the field of NGC 4649 (Table A1)

Images were taken of NGC 4649 using the GMOS in imaging mode on the Gemini North telescope on 2002 April 10, 11 and 14. The internal Gemini program ID is 20020410-GN-2002A-Q-21/Q-13. The instrument consists of three 2048 × 4608 pixel CCDs, with a scale of 0.072 arcsec pixel−1, yielding a 5.5 x 5.5 arcmin2 field-of-view in a single pointing. We obtained three pointings close to the galaxy centre: the north-east (field No. 1), south-east (field No. 2), and east (field No. 3). The images were taken using modified Sloan g and i filters (centred at wavelengths of 475 and 780 nm, respectively). Both g and i images had exposure times of 4 x 120 s, and the subexposures were dithered to remove the gaps between the CCD chips. The seeing for the three fields were similar in the g and i filters, with 0.6, 0.7 and 1.0 arcsec for field Nos 1, 2 and 3, respectively. Table A1 gives the photometry for the resolved objects. Table columns include x and y position in pixels, defined in a rectangular system with its origin at the galaxy centre with x positive towards west and y positive towards the north (columns Xpos and Ypos); galactocentric radius in arcsec (column RadGC); Modified Sloan i magnitude (column imag); Modified Sloan g−i colour index (g-i) and their errors (columns e_imag and e_g-i). Finally, column _RA contains position computed from Xpos and Ypos, assuming the position of M60 centre at 12:43:40.20+11:33:09.0 (right ascension part) (pos.eq.ra;meta.main); and column _DE contains position computed from (Xpos, Ypos), assuming the position of M60 centre at 12:43:40.20+11:33:09.0 (declination part) (pos.eq.dec;meta.main). The table is provided in full for download here in PDF; for other formats including ASCII and HTML, see the Harvard-Smithsonian Center for Astrophysics VizieR record here: http://vizier.u-strasbg.fr/viz-bin/VizieR?-source=J/MNRAS/355/608.

于2002年4月10日、11日及14日，利用智星北望远镜上的GMOS成像模式对NGC 4649进行了图像捕捉。该项目的内部智星程序标识为20020410-GN-2002A-Q-21/Q-13。该仪器由三个2048 × 4608像素的CCD组成，像素尺度为0.072角秒像素−1，单个指向可获得5.5 x 5.5角分平方的视场。我们获取了靠近银河系中心的三个指向图像：东北方向（场号1）、东南方向（场号2）以及东方（场号3）。图像采用改进的斯隆g和i滤光片（分别以475纳米和780纳米的波长为中心）进行捕捉，g和i图像的曝光时间为4 x 120秒，子曝光通过抖动消除CCD芯片之间的缝隙。在g和i滤光片中，三个场号（1、2、3）的视场视见度相似，分别为0.6、0.7和1.0角秒。表A1提供了可分辨物体的光度测量数据。表格列包括像素坐标（x和y），定义在以银河系中心为原点、x轴向西、y轴向北的矩形坐标系中（Xpos和Ypos列）；以角秒为单位的银河中心半径（RadGC列）；改进的斯隆i星等（imag列）；改进的斯隆g−i颜色指数（g-i）及其误差（e_imag和e_g-i列）。最后，_RA列包含从Xpos和Ypos计算出的位置，假设M60中心位于赤经12:43:40.20+11:33:09.0（赤经部分）（pos.eq.ra;meta.main）；而_DE列包含从（Xpos, Ypos）计算出的位置，假设M60中心位于赤经12:43:40.20+11:33:09.0（赤纬部分）（pos.eq.dec;meta.main）。表格全文以PDF格式提供下载；其他格式，包括ASCII和HTML，请参阅哈佛-史密森天体物理中心VizieR记录，链接如下：http://vizier.u-strasbg.fr/viz-bin/VizieR?-source=J/MNRAS/355/608。