The Detection of Bright Asymptotic Giant Branch Stars in the Nearby Elliptical Galaxy Maffei 1

Abstract

We have used the adaptive optics system on the Canada-France-Hawaii Telescope to study a field 6 arcmin from the center of the heavily obscured elliptical galaxy Maffei 1. Our near diffraction-limited H and K' images reveal an excess population of objects with respect to a background field, and we conclude that the asymptotic giant branch tip (AGB-tip) in Maffei 1 occurs at K = 20 +/- 0.25. Assuming that stars at the AGB-tip in Maffei 1 have the same intrinsic luminosity as those in the bulge of M31, then the actual distance modulus of Maffei 1 is 28.2 +/- 0.3 if A_V = 5.1, which corresponds to a distance of 4.4 (+0.6, -0.5) Mpc. This is in excellent agreement with the distance estimated from surface brightness flucuations in the infrared, and confirms that Maffei 1 is too distant to significantly affect the dynamics of the Local Group.