Observing Exoplanets with High-Dispersion Coronagraphy. II. Demonstration of an Active Single-Mode Fiber Injection Unit
Abstract
High-dispersion coronagraphy (HDC) optimally combines high contrast imaging techniques such as adaptive optics/wavefront control plus coronagraphy to high spectral resolution spectroscopy. HDC is a critical pathway towards fully characterizing exoplanet atmospheres across a broad range of masses from giant gaseous planets down to Earth-like planets. In addition to determining the molecular composition of exoplanet atmospheres, HDC also enables Doppler mapping of atmosphere inhomogeneities (temperature, clouds, wind), as well as precise measurements of exoplanet rotational velocities. Here, we demonstrate an innovative concept for injecting the directly-imaged planet light into a single-mode fiber, linking a high-contrast adaptively-corrected coronagraph to a high-resolution spectrograph (diffraction-limited or not). Our laboratory demonstration includes three key milestones: close-to-theoretical injection efficiency, accurate pointing and tracking, on-fiber coherent modulation and speckle nulling of spurious starlight signal coupling into the fiber. Using the extreme modal selectivity of single-mode fibers, we also demonstrated speckle suppression gains that outperform conventional image-based speckle nulling by at least two orders of magnitude.
Additional Information
© 2017. The American Astronomical Society. Received 2016 October 24; revised 2017 February 12; accepted 2017 February 28; published 2017 March 30. The authors would like to acknowledge the referee for the thorough review and constructive comments. The authors would like to acknowledge the financial support of the Heising–Simons foundation. Facility: Caltech's High-Contrast Spectroscopy Testbed for Segmented Telescopes (HCST). -Attached Files
Published - Mawet_2017_ApJ_838_92.pdf
Submitted - 1703.00583.pdf
Supplemental Material - apjaa647ff7_video.mp4
Files
Additional details
- Eprint ID
- 75536
- Resolver ID
- CaltechAUTHORS:20170330-075341818
- Heising-Simons Foundation
- NSF Astronomy and Astrophysics Fellowship
- Created
-
2017-03-30Created from EPrint's datestamp field
- Updated
-
2021-11-15Created from EPrint's last_modified field
- Caltech groups
- Astronomy Department