Exploring calibration algorithms to maximize the null depth in KPIC’s vortex fiber nulling mode

Sofia Hillman; Daniel Echeverri; Maxwell A. Millar-Blanchaer; Jerry Xuan; Garreth Ruane; Dimitri Mawet

doi:10.1117/12.2677037

5 October 2023 Exploring calibration algorithms to maximize the null depth in KPIC’s vortex fiber nulling mode

Sofia Hillman, Daniel Echeverri, Maxwell A. Millar-Blanchaer, Jerry Xuan, Garreth Ruane, Dimitri Mawet

Proceedings Volume 12680, Techniques and Instrumentation for Detection of Exoplanets XI; 126800N (2023) https://doi.org/10.1117/12.2677037
Event: SPIE Optical Engineering + Applications, 2023, San Diego, California, United States

Abstract

Vortex Fiber Nulling (VFN) is a new interferometric technique with the potential to unlock the ability to detect and spectroscopically characterize exoplanets at angular separations smaller than the conventional diffraction limit of λ/D. In early 2022, a VFN mode was added to the Keck Planet Imager and Characterizer (KPIC) instrument suite on Keck II. VFN operates by adding an azimuthal phase ramp to the incident wavefront so that light from the star at the center of the field is prevented from coupling into a single-mode fiber. One of the key performance goals of VFN is to minimize the ratio of on-axis starlight coupling to off-axis planet coupling, which requires minimizing the wavefront aberrations of light being injected into the fiber. Non-common path aberrations can be calibrated during the daytime and compensated for with the KPIC deformable mirror during nighttime observing. By applying different amplitudes of low-order Zernike modes, we determine which combinations maximize the system performance. Here we present our work developing and testing different procedures to estimate the incident aberrations, both in simulation and on the Keck bench. The current iteration of this calibration algorithm has been used successfully for VFN observing, and there are several avenues for improvement.

Conference Presentation

(2023) Published by SPIE. Downloading of the abstract is permitted for personal use only.

Citation Download Citation

Sofia Hillman, Daniel Echeverri, Maxwell A. Millar-Blanchaer, Jerry Xuan, Garreth Ruane, and Dimitri Mawet "Exploring calibration algorithms to maximize the null depth in KPIC’s vortex fiber nulling mode", Proc. SPIE 12680, Techniques and Instrumentation for Detection of Exoplanets XI, 126800N (5 October 2023); https://doi.org/10.1117/12.2677037

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available