HST NIC3 Photometry of Metal-Rich Globular Clusters Palomar 6, Liller 1, and 47 Tuc (NGC 104)

Abstract

We present HST NIC3 photometry of metal-rich globular clusters Palomar 6, Liller 1 and 47 Tuc (NGC 104). We discuss the interstellar reddening law for the HST NICMOS F110W/F160W photometric system which depends on the temperature of the source. The distance moduli and interstellar reddening values for Palomar 6 and Liller 1 are estimated by comparing the magnitudes and colors of RHB stars in the clusters with those of 47 Tuc. We obtain (m-M)0 = 14.48 mag and E(B-V) = 1.34 mag for Palomar 6 and (m-M)0 = 15.17 mag and E(B-V) = 2.50 mag for Liller 1.

Keywords

• Palomar 6
• Liller 1)
• globular clusters: individual(NGC 104; Palomar 6; Liller 1)