论文标题
Ogle-ing-Magellanic系统：红团星星的大小麦芽云的光学红色地图
OGLE-ing the Magellanic System: Optical Reddening Maps of the Large and Small Magellanic Cloud from Red Clump Stars
论文作者
论文摘要
我们介绍了源自红色团块（RC）恒星的颜色特性的麦哲伦云（MCS）的最广泛，最详细的红色地图。该分析基于来自光学引力透镜实验（OGLE-IV）的第四阶段的深度光度图，覆盖了麦哲伦系统区域中约670 deg2的天空。最终的地图为大麦芽云（LMC）中的180 deg2提供了红色的信息，而小麦哲伦云（SMC）中的75 deg2为MCS中央的1.7 x1.7 arcmin分辨率为1.7 x1.7 arcmin，降至郊区的大约27x27 arcmin。在LMC中，平均红色为E（V-I）= 0.100 +-0.043 MAG，E（V-I）= 0.047 +-0.025 mag在SMC中。我们完善了计算RC颜色的方法，以获得基于RC恒星的最高可能的红色地图准确性。使用红色巨人的光谱法，我们发现两个MC中的金属性梯度，这会导致内在的RC颜色略有下降，而LMC的Galaxy中心的距离为〜0.002 mag/deg的距离，在SMC中，LMC的距离为0.002 mag/deg。在LMC和SMC中，内在RC颜色的中心值分别为0.886和0.877 MAG。 MCS的红色映射均以可下载的形式和交互式接口在线可用。
We present the most extensive and detailed reddening maps of the Magellanic Clouds (MCs) derived from the color properties of Red Clump (RC) stars. The analysis is based on the deep photometric maps from the fourth phase of the Optical Gravitational Lensing Experiment (OGLE-IV), covering approximately 670 deg2 of the sky in the Magellanic System region. The resulting maps provide reddening information for 180 deg2 in the Large Magellanic Cloud (LMC) and 75 deg2 in the Small Magellanic Cloud (SMC), with a resolution of 1.7x1.7 arcmin in the central parts of the MCs, decreasing to approximately 27x27 arcmin in the outskirts. The mean reddening is E(V-I) = 0.100 +- 0.043 mag in the LMC and E(V-I) = 0.047 +- 0.025 mag in the SMC. We refine methods of calculating the RC color to obtain the highest possible accuracy of reddening maps based on RC stars. Using spectroscopy of red giants, we find the metallicity gradient in both MCs, which causes a slight decrease of the intrinsic RC color with distance from the galaxy center of ~0.002 mag/deg in the LMC and between 0.003 and 0.009 mag/deg in the SMC. The central values of the intrinsic RC color are 0.886 and 0.877 mag in the LMC and SMC, respectively. The reddening map of the MCs is available on-line both in the downloadable form and as an interactive interface.
