skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: SCExAO/MEC and CHARIS Discovery of a Low-mass, 6 au Separation Companion to HIP 109427 Using Stochastic Speckle Discrimination and High-contrast Spectroscopy

Journal Article · · The Astronomical Journal (Online)
; ; ; ; ; ; ; ; ;  [1]; ; ;  [2];  [3];  [4];  [5]; ;  [6];  [7];  [8] more »; « less
  1. Department of Physics, University of California, Santa Barbara, Santa Barbara, CA (United States)
  2. Subaru Telescope, National Astronomical Observatory of Japan, 650 North A‘ohōkū Place, Hilo, HI 96720 (United States)
  3. Astrobiology Center, 2-21-1, Osawa, Mitaka, Tokyo, 181-8588 (Japan)
  4. Department of Physics, University of Notre Dame, South Bend, IN (United States)
  5. NASA-Goddard Space Flight Center, Greenbelt, MD (United States)
  6. Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91125 (United States)
  7. CERN—1211 Geneva 23— Switzerland (Switzerland)
  8. National Institute of Standards and Technology, Boulder, CO 80305 (United States)

We report the direct imaging discovery of a low-mass companion to the nearby accelerating A star, HIP 109427, with the Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) instrument coupled with the Microwave Kinetic Inductance Detector Exoplanet Camera (MEC) and CHARIS integral field spectrograph. CHARIS data reduced with reference star point spread function (PSF) subtraction yield 1.1–2.4 μm spectra. MEC reveals the companion in Y and J band at a comparable signal-to-noise ratio using stochastic speckle discrimination, with no PSF subtraction techniques. Combined with complementary follow-up L {sub p} photometry from Keck/NIRC2, the SCExAO data favors a spectral type, effective temperature, and luminosity of M4–M5.5, 3000–3200 K, and log{sub 10}(L/L{sub ⊙})=−2.28{sub −0.04}{sup +0.04}, respectively. Relative astrometry of HIP 109427 B from SCExAO/CHARIS and Keck/NIRC2, and complementary Gaia–Hipparcos absolute astrometry of the primary favor a semimajor axis of 6.55{sup +3.0} {sub −0.48} au, an eccentricity of 0.54{sub −0.15}{sup +0.28}, an inclination of 66.7{sub −14}{sup +8.5} degrees, and a dynamical mass of 0.280{sub −0.059}{sup +0.18} M {sub ⊙}. This work shows the potential for extreme AO systems to utilize speckle statistics in addition to widely used postprocessing methods to directly image faint companions to nearby stars near the telescope diffraction limit.

OSTI ID:
23159295
Journal Information:
The Astronomical Journal (Online), Vol. 162, Issue 2; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 1538-3881
Country of Publication:
United States
Language:
English