Deep surface photometry of M87 with 13 optical bands

	Deep surface photometry of M87 with 13 optical bands
	Liu, Y; Zhou, X; Ma, J; Wu, H; Yang, YB; Li, JL; Chen, JS
刊名	ASTRONOMICAL JOURNAL
	2005-06-01
卷号	129 期号:6 页码:2628-2635
关键词	galaxies : evolution galaxies : individual (M87) galaxies : stellar content galaxies : structure
英文摘要	Multicolor surface photometry of M87 was undertaken with the Beijing-Arizona-Taiwan-Connecticut photometric system, which contains 13 optical bands covering a range from 3800 to 10000 angstrom. Radial profiles have been derived for surface brightness, ellipticity, position angle, and the residuals from the fitted ellipses. The results show a good agreement with pure elliptical isophotes for M87, and no obvious substructure or dust is detected out to r = 500 '', corresponding to 40 kpc from the center. The surface brightness profile at r < 190 '' is well fitted by the de Vaucouleurs law. Moreover, a cD envelope is detected outside that radius. Given the surface brightness profiles of the 13 bands, the spectral energy distribution ( SED) of M87 is obtained as a function of semimajor axis (SMA). By fitting the observed SEDs to synthetic ones derived from the PEGASE model, we explored the star formation history (SFH) of this giant elliptical galaxy. In the hypothesis that the evolution time T of M87 is the same as the mean age of its globular clusters, about 14 Gyr, we find that the characteristic timescale tau of the SFH increases monotonically from 2 to 7 Gyr as a function of SMA, while the luminosity-weighted mean stellar ages range from about 11 to 9 Gyr in a mild decrease, and the mean stellar metallicity Z drops from 0.017 to 0.014 as the SMA increases to r = 500 ''. In the range 40 '' < r < 190 '', the metallicity gradient Delta [Fe/H]/Delta [log r] = - 0.04, while in the range 190 '' < r < 400 '', the metallicity gradient Delta[Fe/H]/Delta[log r] = -0.17.
收录类别	SCI
语种	英语
WOS记录号	WOS:000229472400009
内容类型	期刊论文
源URL	[http://ir.bao.ac.cn/handle/114a11/8148]
专题	国家天文台_光学天文研究部
作者单位	Chinese Acad Sci, Natl Astron Observ, Beijing 100012, Peoples R China
推荐引用方式 GB/T 7714	Liu, Y,Zhou, X,Ma, J,et al. Deep surface photometry of M87 with 13 optical bands[J]. ASTRONOMICAL JOURNAL,2005,129(6):2628-2635.
APA	Liu, Y.,Zhou, X.,Ma, J.,Wu, H.,Yang, YB.,...&Chen, JS.(2005).Deep surface photometry of M87 with 13 optical bands.ASTRONOMICAL JOURNAL,129(6),2628-2635.
MLA	Liu, Y,et al."Deep surface photometry of M87 with 13 optical bands".ASTRONOMICAL JOURNAL 129.6(2005):2628-2635.