晚型旋涡星系盘的颜色梯度  

Color Gradients in the Disks of Late-type Spiral Galaxies

作　　者：李化南[1] 邵正义[1] 肖泉宝[1] 刘成则[1] 

机构地区：[1]中国科学院上海天文台,上海200030

出　　处：《天文学进展》2005年第4期371-378,共8页Progress In Astronomy

基　　金：国家自然科学基金重点资助项目(10273016;10333060)

摘　　要：从Sloan巡天第二批释放的数据(Sloan Digital Sky Survey, Data Release Two)中选择了395个在r波段亮于15 mag的晚型旋涡星系作为样本，对样本星系的表面亮度轮廓进行一维两成分(核球与盘)拟合，并着重讨论了盘的颜色梯度，分别用Δc／ΔR和Δc／Δlg R两种形式来拟合。结果表明，对于波长相距较大的颜色r-z和g-z，颜色梯度更符合Δc／ΔR为常数的线性变化形式，而g-r则符合Δc／ΔlgR为线性的情形；用Δc／ΔlgR拟合的梯度值分别为Δ(9-r)／ΔlgR=-0.152±0.010，Δ(r-z)／ΔlgR=-0.377±0.019，Δ(g-z)／ΔlgR=-0.590±0.026，均与前人的研究结果一致。Based on 395 late-type spiral galaxies brighter than 15 mag in r-band that selected from Data Release Two of Slogan Digital Sky Survey, we decompose their bulges and disks through one-dimensional fitting of the surface brightness profile, and statistically analyze the color gradients in their disks. We fit the color gradients by the forms of △c/△R and △c/△lg R separately. It can be found that the gradients in the colors of r - z and g - z are roughly constant in △c/△R, while g - r favors the form of △c/△lg R. The values of color gradients are： △（g - r）/△lg R = -0.152±0.010, △（r - z）/△lg R = -0.377±0.019, △（g - z）/△lg R = -0.590±0.026, which are in good agreement with previous results.

关 键 词：天体物理学 颜色梯度 一维两成分拟合 旋涡星系 盘 

分 类 号：P157[天文地球—天文学]