Imaging and polarimetry of the galactic-center in the near infrared

Abstract

IR images of the Galactic center in H, K, L-prime and M are the bases of the present measurements of positions, magnitudes and colors for 35 sources which can be divided into two classes: those with colors typical of reddened stars, and those with much redder colors which dominate at L-prime and M, having a dust emission IR source. Polarization measurements have been made for a number of the brighter sources at J, H, and K. IRS 16 is typical of a group whose stellar colors show the wavelength dependence of interstellar polarization. IRS 1 exhibits substantial intrinsic polarization at K, attributable to aligned grain emission. The small circular polarization of IRS 7 may be due to the effect of stellar birefringence on intrinsic polarization.