The Astronomical Journal (Jan 2024)
JWST-TST High Contrast: Achieving Direct Spectroscopy of Faint Substellar Companions Next to Bright Stars with the NIRSpec Integral Field Unit
- Jean-Baptiste Ruffio,
- Marshall D. Perrin,
- Kielan K. W. Hoch,
- Jens Kammerer,
- Quinn M. Konopacky,
- Laurent Pueyo,
- Alex Madurowicz,
- Emily Rickman,
- Christopher A. Theissen,
- Shubh Agrawal,
- Alexandra Z. Greenbaum,
- Brittany E. Miles,
- Travis S. Barman,
- William O. Balmer,
- Jorge Llop-Sayson,
- Julien H. Girard,
- Isabel Rebollido,
- Rémi Soummer,
- Natalie H. Allen,
- Jay Anderson,
- Charles A. Beichman,
- Andrea Bellini,
- Geoffrey Bryden,
- Néstor Espinoza,
- Ana Glidden,
- Jingcheng Huang,
- Nikole K. Lewis,
- Mattia Libralato,
- Dana R. Louie,
- Sangmo Tony Sohn,
- Sara Seager,
- Roeland P. van der Marel,
- Hannah R. Wakeford,
- Laura L. Watkins,
- Marie Ygouf,
- C. Matt Mountain
Affiliations
- Jean-Baptiste Ruffio
- ORCiD
- Department of Astronomy & Astrophysics, University of California , San Diego, La Jolla, CA 92093, USA ; [email protected]
- Marshall D. Perrin
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Kielan K. W. Hoch
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Jens Kammerer
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA; European Southern Observatory , Karl-Schwarzschild-Str. 2, 85748 Garching, Germany
- Quinn M. Konopacky
- ORCiD
- Department of Astronomy & Astrophysics, University of California , San Diego, La Jolla, CA 92093, USA ; [email protected]
- Laurent Pueyo
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Alex Madurowicz
- ORCiD
- Department of Astronomy & Astrophysics, University of California , Santa Cruz, CA95064, USA
- Emily Rickman
- ORCiD
- European Space Agency (ESA), ESA Office, Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Christopher A. Theissen
- ORCiD
- Department of Astronomy & Astrophysics, University of California , San Diego, La Jolla, CA 92093, USA ; [email protected]
- Shubh Agrawal
- ORCiD
- Department of Physics and Astronomy, University of Pennsylvania , Philadelphia, PA 19104, USA
- Alexandra Z. Greenbaum
- ORCiD
- IPAC, Mail Code 100-22, California Institute of Technology , 1200 E. California Boulevard, Pasadena, CA 91125, USA
- Brittany E. Miles
- ORCiD
- Steward Observatory, University of Arizona , 933 N. Cherry Avenue, Tucson, AZ 85721, USA
- Travis S. Barman
- ORCiD
- Lunar and Planetary Laboratory, University of Arizona , Tucson, AZ 85721, USA
- William O. Balmer
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA; William H. Miller III Department of Physics and Astronomy, Johns Hopkins University , Baltimore, MD 21218, USA
- Jorge Llop-Sayson
- ORCiD
- California Institute of Technology , 1200 E California Boulevard, Pasadena, CA 91125, USA
- Julien H. Girard
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Isabel Rebollido
- ORCiD
- Centro de Astrobiología (CAB, CSIC-INTA) , ESAC Campus Camino Bajo del Castillo, s/n, Villanueva de la Cañada, E-28692 Madrid, Spain
- Rémi Soummer
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Natalie H. Allen
- ORCiD
- William H. Miller III Department of Physics and Astronomy, Johns Hopkins University , Baltimore, MD 21218, USA
- Jay Anderson
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Charles A. Beichman
- ORCiD
- NASA Exoplanet Science Institute/IPAC, Jet Propulsion Laboratory, California Institute of Technology , 1200 E California Boulevard, Pasadena, CA 91125, USA
- Andrea Bellini
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Geoffrey Bryden
- ORCiD
- Jet Propulsion Laboratory, California Institute of Technology , 4800 Oak Grove Drive, Pasadena, CA 91109, USA
- Néstor Espinoza
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA; William H. Miller III Department of Physics and Astronomy, Johns Hopkins University , Baltimore, MD 21218, USA
- Ana Glidden
- ORCiD
- Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology , Cambridge, MA 02139, USA; Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology , Cambridge, MA 02139, USA
- Jingcheng Huang
- ORCiD
- Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology , Cambridge, MA 02139, USA
- Nikole K. Lewis
- ORCiD
- Department of Astronomy and Carl Sagan Institute, Cornell University , 122 Sciences Drive, Ithaca, NY 14853, USA
- Mattia Libralato
- ORCiD
- AURA for the European Space Agency (ESA), Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Dana R. Louie
- ORCiD
- NASA Goddard Space Flight Center , Greenbelt, MD 20771, USA
- Sangmo Tony Sohn
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Sara Seager
- ORCiD
- Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology , Cambridge, MA 02139, USA; Department of Physics and Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology , Cambridge, MA 02139, USA; Department of Aeronautics and Astronautics , MIT, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
- Roeland P. van der Marel
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA; William H. Miller III Department of Physics and Astronomy, Johns Hopkins University , Baltimore, MD 21218, USA
- Hannah R. Wakeford
- ORCiD
- University of Bristol , HH Wills Physics Laboratory, Tyndall Avenue, Bristol, UK
- Laura L. Watkins
- ORCiD
- AURA for the European Space Agency (ESA), Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Marie Ygouf
- ORCiD
- Jet Propulsion Laboratory, California Institute of Technology , 4800 Oak Grove Drive, Pasadena, CA 91109, USA
- C. Matt Mountain
- Association of Universities for Research in Astronomy , 1331 Pennsylvania Avenue, NW Suite 1475, Washington, DC 20004, USA
- DOI
- https://doi.org/10.3847/1538-3881/ad5281
- Journal volume & issue
-
Vol. 168,
no. 2
p. 73
Abstract
The JWST NIRSpec integral field unit (IFU) presents a unique opportunity to observe directly imaged exoplanets from 3 to 5 μ m at moderate spectral resolution ( R ∼ 2700) and thereby better constrain the composition, disequilibrium chemistry, and cloud properties of their atmospheres. In this work, we present the first NIRSpec IFU high-contrast observations of a substellar companion that requires starlight suppression techniques. We develop specific data-reduction strategies to study faint companions around bright stars and assess the performance of NIRSpec at high contrast. First, we demonstrate an approach to forward model the companion signal and the starlight directly in the detector images, which mitigates the effects of NIRSpec’s spatial undersampling. We demonstrate a sensitivity to planets that are 3 × 10 ^−6 fainter than their stars at 1″, or 3 × 10 ^−5 at 0.″3. Then, we implement a reference star point-spread function subtraction and a spectral extraction that does not require spatially and spectrally regularly sampled spectral cubes. This allows us to extract a moderate resolution ( R ∼ 2,700) spectrum of the faint T dwarf companion HD 19467 B from 2.9 to 5.2 μ m with a signal-to-noise ratio of ∼10 per resolution element. Across this wavelength range, HD 19467 B has a flux ratio varying between 10 ^−5 and 10 ^−4 and a separation relative to its star of 1.″6. A companion paper by Hoch et al. more deeply analyzes the atmospheric properties of this companion based on the extracted spectrum. Using the methods developed here, NIRSpec’s sensitivity may enable direct detection and spectral characterization of relatively old (∼1 Gyr), cool (∼250 K), and closely separated (∼3–5 au) exoplanets that are less massive than Jupiter.
Keywords
- Direct imaging
- High contrast spectroscopy
- High resolution spectroscopy
- Near infrared astronomy
- Extrasolar gaseous giant planets
