An infrared study of the stellar population in the direction of the Carina nebula: NGC 3372

Abstract

Surveys at two microns are used to identify the brightest members of the stellar population in the direction of the Carina nebula, and JHK photometry has been used to identify several heavily reddened new members of the Tr14/16 association. The distribution of reddening material determined from background field star color-excesses is found to agree with the distribution of neutral material suggested by previous data. A study of the Tr14/16OB stars shows the reddening law to be anomalous for all stars in the sample, characterized by a unique value of the ratio of total-to-selective extinction of 4.8. Consideration of the reddening law normalized to E(V-J) leads to the indication that the extinction anomaly affects only the extinction in the U and B bandpasses, providing strong constraints on models of the grain size distribution within the Carina nebula.