Using Data Release 4 of the Sloan Digital Sky Survey, we have applied an optimal contrast, matched filter technique to trace the trailing tidal tail of the globular cluster Palomar 5 to a distance of 18.5 degrees from the center of the cluster. This more than doubles the total known length of the tail to some 22 degrees on the sky. Based on a simple model of the Galaxy, we find that the stream's orientation on the sky is consistent at the 1.7 sigma level with existing proper motion measurements. We find that a spherical Galactic halo is adequate to model the stream over its currently known length, and we are able to place new constraints on the current space motion of the cluster.
@article{arxiv.astro-ph/0603062,
title = {A 22 Degree Tidal Tail for Palomar 5},
author = {C. J. Grillmair and O. Dionatos},
journal= {arXiv preprint arXiv:astro-ph/0603062},
year = {2009}
}
Comments
10 pages, 3 figures, accepted for publication in ApJ Letters