Vortex Fiber Nulling for Exoplanet Observations: First Direct Detection of M Dwarf Companions around HIP 21543, HIP 94666, and HIP 50319

Creators: Echeverri, Daniel; Xuan, Jerry W.; Monnier, John D.; Delorme, Jacques-Robert; Wang, Jason J.; Jovanovic, Nemanja¹; Horstman, Katelyn; Ruane, Garreth; Mennesson, Bertrand; Serabyn, Eugene; Mawet, Dimitri¹; Wallace, J. Kent; Hillman, Sofia; Baker, Ashley; Bartos, Randall; Calvin, Benjamin; Cetre, Sylvain; Doppmann, Greg; Finnerty, Luke; Fitzgerald, Michael P.; Hsu, Chih-Chun; Liberman, Joshua; López, Ronald; Millar-Blanchaer, Maxwell; Morris, Evan; Pezzato, Jacklyn; Ruffio, Jean-Baptiste; Sappey, Ben; Schofield, Tobias; Skemer, Andrew J.; Wang, Ji; Xin, Yinzi; Anugu, Narsireddy; Chhabra, Sorabh; Ibrahim, Noura; Kraus, Stefan; Schaefer, Gail H.; Lanthermann, Cyprien

1. California Institute of Technology

Abstract

Abstract Vortex fiber nulling (VFN) is a technique for detecting and characterizing faint companions at small separations from their host star. A near-infrared (∼2.3 μm) VFN demonstrator mode was deployed on the Keck Planet Imager and Characterizer (KPIC) instrument at the Keck Observatory and presented earlier. In this Letter, we present the first VFN companion detections. Three targets, HIP 21543 Ab, HIP 94666 Ab, and HIP 50319 B, were detected with host–companion flux ratios between 70 and 430 at and within one diffraction beamwidth (λ/D). We complement the spectra from KPIC VFN with flux ratio and position measurements from the CHARA Array to validate the VFN results and provide a more complete characterization of the targets. This Letter reports the first direct detection of these three M dwarf companions, yielding their first spectra and flux ratios. Our observations provide measurements of bulk properties such as effective temperatures, radial velocities, and v sin i , and verify the accuracy of the published orbits. These detections corroborate earlier predictions of the KPIC VFN performance, demonstrating that the instrument mode is ready for science observations.

Copyright and License

© 2024. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

Acknowledgement

D.E. was supported by a NASA Future Investigators in NASA Earth and Space Science and Technology (FINESST) fellowship under award #80NSSC19K1423. D.E. also acknowledges support from the Keck Visiting Scholars Program (KVSP) to install the KPIC Phase II upgrades required for KPIC VFN. J.X. is supported by another FINESST award under #80NSSC23K1434 and also acknowledges support from the KVSP to commission KPIC Phase II.

Funding for KPIC has been provided by the California Institute of Technology, the Jet Propulsion Laboratory, the Heising-Simons Foundation (grants #2015-129, #2017-318, #2019-1312, and #2023-4598), the Simons Foundation (through the Caltech Center for Comparative Planetary Evolution), and the NSF under grant AST-1611623.

This work is based upon observations obtained with the Georgia State University Center for High Angular Resolution Astronomy Array at Mount Wilson Observatory. The CHARA Array is supported by the National Science Foundation under grant Nos. AST-1636624 and AST-2034336. Institutional support has been provided from the GSU College of Arts and Sciences and the GSU Office of the Vice President for Research and Economic Development. S.K. and S.C. acknowledge funding for MIRC-X received from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (starting grant No. 639889 and consolidated grant No. 101003096). J.D.M. acknowledges funding for the development of MIRC-X (NASA-XRP NNX16AD43G, NSF-AST 1909165) and MYSTIC (NSF-ATI 1506540, NSF-AST 1909165).

The data presented herein were obtained at Keck Observatory, which is a private 501(c)3 nonprofit organization operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation.

Some of this work was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration and funded through the internal Research and Technology Development program.

This work has made use of data from the European Space Agency (ESA) mission Gaia (https://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC; https://www.cosmos.esa.int/web/gaia/dpac/consortium). Funding for the DPAC has been provided by national institutions, in particular, the institutions participating in the Gaia Multilateral Agreement.

The authors wish to recognize and acknowledge the very significant cultural role and reverence that the summit of Maunakea has always had within the indigenous Hawaiian community. We are most fortunate to have the opportunity to conduct observations from this mountain.