arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1706.03338astro-ph.SRastro-ph.GA
收藏

基于2 MASS测光的3D恒星变红图的改进

3D Stellar Reddening Map from 2MASS Photometry: An Improved Version

George Gontcharov

备注：
a new version of the map, instead of 2010AstL...36..584G
发表信息：
Astronomy Letters, 43, 471-487, 2017
阅读 PDF
arXiv 页面 ↗HTML 原文 ↗

摘要：

本文提出了一个改进的3D恒星红化图，它是在太阳周围半径为1200 pc，距银河系中平面600 pc以内的空间中绘制的。与之前的2010年和2012年版本的地图一样，新版本中使用了2 MASS目录中超过7000万颗恒星的$J$和$K_s$波段的测光，其精度优于$0.05^m$。然而，数据简化技术要复杂得多。如前所述，在$(J-K_s)$ - $K_s$图上，对主序星转折点附近的恒星分布进行分析，在那里它们形成分布最大值，为该方法提供了基础。该最大值的偏移，即，根据这些恒星平均去红颜色$(J-K_s)_0$的空间变化，沿$(J-K_s)$和$K_s$的$mode(J-K_s)$被解释为红化随距离增加而增长。新方法的主要区别是，不是固定的平均绝对星等，去红颜色，距离和每个细胞的红化，这些量的个别值是通过迭代计算每个恒星时，求解方程组相关。这使得人们可以将$0.01^m$地图的随机精度和空间分辨率提高到20 pc（坐标和距离）和$1^{\circ}$（经度和纬度）。与其他红化估计相同的空间细胞和盖亚DR 1 TGAS星的比较表明，所构建的地图是考虑中的空间的最佳地图之一。其系统误差估计为$σ(E(J-K_s))=0.025^m$或$σ(E(B-V))=0.04^m$。该地图的主要目的是分析银河系结构，云和云复合体的特征。为此，还通过分析沿每条视线的红化来计算每个空间单元内的红化图。

英文摘要：

An improved version of the 3D stellar reddening map in a space with a radius of 1200 pc around the Sun and within 600 pc of the Galactic midplane is presented. As in the previous 2010 and 2012 versions of the map, photometry with an accuracy better than $0.05^m$ in the $J$ and $K_s$ bands for more than 70 million stars from the 2MASS catalogue is used in the new version. However, the data reduction technique is considerably more complicated. As before, an analysis of the distribution of stars near the main-sequence turnoff on the $(J-K_s)$ - $K_s$ diagram, where they form a distribution maximum, provides a basis for the method. The shift of this maximum, i.e., the $mode(J-K_s)$, along $(J-K_s)$ and $K_s$, given the spatial variations of the mean de-reddened color $(J-K_s)_0$ of these stars, is interpreted as a growth of the reddening with increasing distance. The main distinction of the new method is that instead of the fixed mean absolute magnitude, de-reddened color, distance, and reddening for each cell, the individual values of these quantities are calculated for each star by iterations when solving the system of equations relating them. This has allowed one to increase the random accuracy of the map to $0.01^m$ and its spatial resolution to 20 pc in coordinates and distance and to $1^{\circ}$ in longitude and latitude. Comparison with other reddening estimates for the same spatial cells and Gaia DR1 TGAS stars shows that the constructed map is one of the best maps for the space under consideration. Its systematic errors have been estimated to be $σ(E(J-K_s))=0.025^m$, or $σ(E(B-V))=0.04^m$. The main purpose of the map is to analyze the characteristics of Galactic structures, clouds, and cloud complexes. For this purpose, the reddening map within each spatial cell has also been computed by analyzing the reddening along each line of sight.

机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。

↑