A Faint Halo Star Cluster Discovered in the Blanco Imaging of the Southern Sky Survey
Bechtol, K.; Allam, S.; Kuropatkin, N.; Soares-Santos, M.; Palmese, A.; Tucker, D.; Drlica-Wagner, A.; Yanny, B.; Mau, S.; Pace, A. B.; Santana-Silva, L.; Jethwa, P.; Li, T.; Chen, H. -Y.; Vivas, K.; Burgad, C.; BLISS Collaboration
United States, Brazil, Germany, Chile
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 ({α }2000,{δ }2000)=(177\buildrel{\circ}\over{.} 511,-41\buildrel{\circ}\over{.} 772) with a heliocentric distance of {D}⊙ ={23.7}-1.0+1.9 {kpc}. It is a faint, {M}V={0.0}-0.7+1.7 {mag}, and compact, {r}h={4.1}-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 ({μ }α \cos δ ,{μ }δ )=(-2.37+/- 0.06,0.16+/- 0.04) mas yr-1. Combining the available positional and velocity information with simulations of the accreted satellite population of the Large Magellanic Cloud (LMC), we find that it is unlikely that BLISS J0321+0438 (BLISS 1) originated with the LMC.