Constraining the Galactic structure parameters with the XSTPS-GAC and SDSS photometric surveys
Constraining the Galactic structure parameters with the XSTPS-GAC and SDSS photometric surveys
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通过 XSTPS-GAC 和 SDSS 光度测量约束银河系结构参数
DOI：
10.1093/mnras/stw2497
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发表时间：
2016-09
影响因子：
4.8
通讯作者：
Zhang H. -W.
中科院分区：
文献类型：
--
作者：
Chen B. -Q.;Liu X. -W.;Yuan H. -B.;Robin A. C.;Huang Y.;Xiang M. -S.;Wang C.;Ren J. -J.;Tian Z. -J.;Zhang H. -W.
利用盱眙施密特望远镜银心光度巡天（XSTPS-GAC）和斯隆数字巡天（SDSS）的光度数据，计算了银河系平滑分量的整体结构参数。这些数据覆盖了近11,000度的天空区域和整个银河系的纬度范围，使我们能够构建一个具有全球代表性的银河系模型。银河晕星的数密度分布符合幂律衰减的扁球体。最佳拟合产生轴比和幂律指数$\kappa=0.65$和$p=2.79$，分别。然后用银河系模型拟合了三个矮星样品的r波段微分星星计数。用马尔可夫链蒙特卡罗分析得到的最佳拟合模型的厚、薄盘高度和长度分别为H_{1}= 322，pc和L_{1}= 2343，pc，H_{2}= 794，pc和L_{2}= 3638，pc，局部厚、薄盘密度比为f_2 = 11，p_cent，扁圆晕与薄盘的局部密度比为$f_h=$0.16%.测量的星星计数分布与上述模型在大部分天区的分布很好地吻合，显示出许多统计上显著的大尺度超密度，包括一些以前已知的子结构，例如室女座超密度和所谓的“北近结构”，以及在1.0和1.5千秒差距之间的150 ° < l <$240 ° ~和$-1$5 ° < B < $ $-$5 °之间的新特征。银河系在反中心的南北不对称性甚至比以前认为的还要强。
Photometric data from the Xuyi Schmidt Telescope Photometric Survey of the Galactic Anticentre (XSTPS-GAC) and the Sloan Digital Sky Survey (SDSS) are used to derive the global structure parameters of the smooth components of the Milky Way. The data, which cover nearly 11,000 deg$^2$ sky area and the full range of Galactic latitude, allow us to construct a globally representative Galactic model. The number density distribution of Galactic halo stars is fitted with an oblate spheroid that decays by power law. The best-fit yields an axis ratio and a power law index $\kappa=0.65$ and $p=2.79$, respectively. The $r$-band differential star counts of three dwarf samples are then fitted with a Galactic model. The best-fit model yielded by a Markov Chain Monte Carlo analysis has thin and thick disk scale heights and lengths of $H_{1}=$ 322\,pc and $L_{1}=$2343\,pc, $H_{2}=$794\,pc and $L_{2}=$3638\,pc, a local thick-to-thin disk density ratio of $f_2=$11\,per\,cent, and a local density ratio of the oblate halo to the thin disk of $f_h=$0.16\,per\,cent. The measured star count distribution, which is in good agreement with the above model for most of the sky area, shows a number of statistically significant large scale overdensities, including some of the previously known substructures, such as the Virgo overdensity and the so-called "north near structure", and a new feature between 150\degr $< l < $ 240\degr~and $-1$5\degr $< b < $ $-$5\degr, at an estimated distance between 1.0 and 1.5\,kpc. The Galactic North-South asymmetry in the anticentre is even stronger than previously thought.
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LSS-GAC 主序关闭星的银河系盘恒星金属丰度梯度的演化：两相盘形成历史？
影响因子：
1.8
作者：
Xiang Mao-Sheng;Liu Xiao-Wei;Yuan Hai-Bo;Huang Yang;Wang Chun;Ren Juan-Juan;Chen Bing-Qiu;Sun Ning-Chen;Zhang Hua-Wei;Huo Zhi-Ying;Rebassa-Mansergas Alberto
通讯作者：
Rebassa-Mansergas Alberto
影响因子：
6.3
作者：
S. Karaali;S. Bilir;E. Yaz;E. Hamzaoğlu;R. Buser
通讯作者：
S. Karaali;S. Bilir;E. Yaz;E. Hamzaoğlu;R. Buser
DOI：
10.1046/j.1365-8711.2003.06545.x
发表时间：
2003-01
影响因子：
4.8
作者：
R. Ibata;G. Lewis;A. Ferguson;M. Irwin;N. Tanvir
通讯作者：
R. Ibata;G. Lewis;A. Ferguson;M. Irwin;N. Tanvir
DOI：
10.1086/379504
发表时间：
2003-04
期刊：
The Astrophysical Journal
影响因子：
--
作者：
S. Majewski;M. Skrutskie;M. Weinberg;J. A. I. U. O. Virginia;U. Massachusetts
通讯作者：
S. Majewski;M. Skrutskie;M. Weinberg;J. A. I. U. O. Virginia;U. Massachusetts
DOI：
10.1086/338983
发表时间：
2001-11
期刊：
The Astrophysical Journal
影响因子：
--
作者：
H. Newberg;B. Yanny;C. Rockosi;E. Grebel;H. Rix;J. Brinkmann;I. Csabai;G. Hennessy;R. Hindsley-R.-Hi
通讯作者：
H. Newberg;B. Yanny;C. Rockosi;E. Grebel;H. Rix;J. Brinkmann;I. Csabai;G. Hennessy;R. Hindsley-R.-Hi