Circumstellar shells in the young cluster NGC 2264. II - Infrared and further optical observations.

Flux measurements at 1.6, 2.2, and 3.4 microns for 42 stars in the young cluster NGC 2264 suggest that a significant number of these stars are surrounded by circumstellar material which produces observable infrared excesses. Hydrogen line profiles are used to estimate surface gravities and thereby to predict visual luminosities for a number of pre-main-sequence A stars. Those stars which appear faintest as compared with their predicted luminosities all have infrared excesses.