The M4 Core Project with HST --- I. Overview and First-Epoch
Abstract
We present an overview of the ongoing Hubble Space Telescope large program GO-12911. The program is focused on the core of M4, the nearest Galactic globular cluster, and the observations are designed to constrain the number of binaries with massive companions (black holes, neutron stars, or white dwarfs) by measuring the ``wobble'' of the luminous (main-sequence) companion around the center of mass of the pair, with an astrometric precision of ~50 micro-arcseconds. The high spatial resolution and stable medium-band PSFs of WFC3/UVIS will make these measurements possible. In this work we describe: (i) the motivation behind this study, (ii) our observing strategy, (iii) the many other investigations enabled by this unique data set, and which of those our team is conducting, and (iv) a preliminary reduction of the first-epoch data-set collected on October 10, 2012.
Cite
@article{arxiv.1312.1096,
title = {The M4 Core Project with HST --- I. Overview and First-Epoch},
author = {L. R. Bedin and J. Anderson and D. C. Heggie and G. Piotto and A. P. Milone and M. Giersz and V. Nascimbeni and A. Bellini and R. M. Rich and M. van den Berg and D. Pooley and K. Brogaard and S. Ortolani and L. Malavolta and L. Ubeda and A. F. Marino and .},
journal= {arXiv preprint arXiv:1312.1096},
year = {2015}
}
Comments
25 pages, 14 figures (9 at low resolution), 3 tables. Published in: Astronomische Nachrichten, Volume 334, Issue 10, pages 1062-1085, December 2013. http://onlinelibrary.wiley.com/doi/10.1002/asna.201311911/abstract