标题： 使用光学恒星计数绘制巨分子云的消光图 显示英文标题

标题： Mapping of the extinction in Giant Molecular Clouds using optical star counts

摘要： 本文利用基于自适应网格和小波分解的恒星计数方法，结合美国海军天文台精密测量机提供的光学数据，给出了银河系大多数近邻巨型分子云（包括卢普斯、ρ-蛇夫座、天蝎座、煤袋星云、金牛座、蝘蜓座、摩羯座、南十字座、蛇夫座、IC 5146、船尾座、猎户座、麒麟座R1和R2、玫瑰星云、船底座）的大规模消光图。通过对这些云中消光分布的研究，可以估算出它们各自的总质量M和最大消光值。 我表明，位于等消光轮廓内所包含的质量与消光之间的关系在各个云之间相似，这使得我们可以将最大消光值从5.7到25.5星等范围内的消光值进行外推。 我发现大约一半的质量集中在视觉消光小于1星等的区域。 在大尺度上（约250平方度）使用恒星计数方法是一种强大且相对直接的方法来估计分子复合体的质量。 对全天系统性的研究可能会发现新的云，就像我在卢普斯复合体中所做的那样，我发现了第六个质量约为10^4太阳质量的云。 显示英文摘要

摘要： This paper presents large scale extinction maps of most nearby Giant Molecular Clouds of the Galaxy (Lupus, rho-Ophiuchus, Scorpius, Coalsack, Taurus, Chamaeleon, Musca, Corona Australis, Serpens, IC 5146, Vela, Orion, Monoceros R1 and R2, Rosette, Carina) derived from a star count method using an adaptive grid and a wavelet decomposition applied to the optical data provided by the USNO-Precision Measuring Machine. The distribution of the extinction in the clouds leads to estimate their total individual masses M and their maximum of extinction. I show that the relation between the mass contained within an iso-extinction contour and the extinction is similar from cloud to cloud and allows the extrapolation of the maximum of extinction in the range 5.7 to 25.5 magnitudes. I found that about half of the mass is contained in regions where the visual extinction is smaller than 1 magnitude. The star count method used on large scale (about 250 square degrees) is a powerful and relatively straightforward method to estimate the mass of molecular complexes. A systematic study of the all sky would lead to discover new clouds as I did in the Lupus complex for which I found a sixth cloud of about 10^4 solar masses.