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arXiv · 1812.06318

A faint halo star cluster discovered in the Blanco Imaging of the Southern Sky Survey

S. Mau·A. Drlica-Wagner·K. Bechtol·A. B. Pace·T. Li·M. Soares-Santos·N. Kuropatkin·S. Allam·D. Tucker·L. Santana-Silva·B. Yanny·P. Jethwa·A. Palmese·K. Vivas·C. Burgad·H. -Y. Chen
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Abstract

We present the discovery of a faint, resolved stellar system, BLISS J0321+0438 (BLISS 1), found in Dark Energy Camera data from the first observing run of the Blanco Imaging of the Southern Sky (BLISS) Survey. BLISS J0321+0438 (BLISS 1) is located at (RA, Dec) = (177.511, -41.772) deg with a heliocentric distance of D = 23.7$^{+1.9}_{-1.0}$ kpc. It is a faint, Mv = 0.0$^{+1.7}_{-0.7}$ mag, and compact, rh = 4.1 +/- 1 pc, system consistent with previously discovered faint halo star clusters. Using data from the second data release of the Gaia satellite, we measure a proper motion of $(\mu_\alpha \cos \delta, \mu_\delta)$ = (-2.37 +/- 0.06, 0.16 +/- 0.04) mas/yr. Combining the available positional and velocity information with simulations of the accreted satellite population of the Large Magellanic Cloud, we find that it is unlikely that BLISS J0321+0438 (BLISS 1) originated with the Large Magellanic Cloud.

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S. Mau, A. Drlica-Wagner, K. Bechtol, A. B. Pace, T. Li, M. Soares-Santos, N. Kuropatkin, S. Allam, D. Tucker, L. Santana-Silva, B. Yanny, P. Jethwa, A. Palmese, K. Vivas, C. Burgad, H. -Y. Chen. 2018-12-15. A faint halo star cluster discovered in the Blanco Imaging of the Southern Sky Survey. https://doi.org/10.3847/1538-4357%2Fab0bb8

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