Targeted Search for Milky Way Satellites Using HSC

POSTER

Abstract

We present the results from a targeted search for new Milky Way (MW) satellites based on survey data from the Hyper-Suprime Cam (HSC) Subaru Strategic Program. HSC has deep photometry which enables the discovery of ultra faint dwarf galaxies in the galactic halo. We choose this region because the galactic halo contains stars that are tracers of old metal-poor stellar populations similar to those seen in the known dwarf galaxies around the MW: RR Lyrae, K Giants, and Blue Horizontal Branch stars. We locate these types of stars in the HSC footprint, and use their accurate heliodistances to determine whether they are satellite galaxies. This is done by discovering spatial overdensities of resolved stellar sources against foreground stars and background galaxies around our tracer star. Our method has yet to yield detections of MW satellites, but remains promising for the upcoming LSST survey. Knowing where the MW dwarf might be and knowing its distance from target stars will allow LSST to provide a great wealth of information for the open question of Dark Matter and Dark Energy. Still, future work on this project would be to analyze more HSC data upon release or to quantify at what limits we can say that there are no galaxies around the searched regions.

Authors

  • Bethlee Lindor

    Princeton University

  • Debbie Andres

    Department of Applied Physics and Department of Physics, Columbia University, Istituto Italiano di Tecnologia, Graphene Labs, Italy, Department of Physics and Astronomy, Purdue University, Department of Electrical Engineering, Princeton University, Department of Applied Physics and Applied Mathematics, Columbia University, NJIT, New Jersey Inst of Technology, New Jersey Inst of Tech, New Jersey Institute of Technology, Center for Advanced Radiation Sources, University of Chicago, High Pressure Science and Technology Advanced Research, State University of New York at Stony Brook, Rutgers University, NIST, Brookhaven National Laboratory, University of Chicago, University of South Florida, ETH Zurich, Max Planck POSTECH/Korea Research Initiative, University of Virginia, Rutgers University - Camden, New Jersey Institute of technology, Shaanxi Normal University, Pohang Science and Technology University, Sungkyunkwan University, Northern Illinois University and Argonne National Laboratory, Beijing National Laboratory for Condensed Matter Physics , and Institute of Physics, Chinese Academy of Sciences, Rutgers U., Orsova Engineers, U.S. Naval Research Laboratory, Center for Space Science and Engineering Research, Virginia Tech, Virginia., Princeton University, NASA Goddard Space Flight Center, Villanova University, SOFIA/USRA, Jet Propulsion Laboratory, Hudson Regional Health Commision, Rutgers University, College of William & Mary, Department of Physics, Drexel University, Drexel University, Drexel Universty, University of Massachusetts Amherst, Pohang Institue of Science and Technology, Indiana University - Purdue University Indianapolis, Department of Physics, University of Maryland, Naval Research Laboratory, Towson Univ, Rice University, Independence Blue Cross Cardiovascular Research Center, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, Department of Physics, Temple University, PulseTorr LLC, Department of Chemistry, West Chester University, Department of Physics, West Chester University, College of William and Mary Dept. of Physics, University of Virginia Dept. of Materials Science and Engineering, United States Naval Academy, Rutgers The State University of New Jersey, Univ of Maryland-College Park, Los Alamos National Laboratory, POSTECH, New Jersey Institute of Technology, Department of Electrical and Computer Engineering, HamSCI/ARRL, Virginia Tech, Rutgers University-Camden, University of Washington, Rutgers, The State University of New Jersey