papers

Publications (6)

astro-ph.IM2026

Commissioning and on-sky performance verification of iLocater

Marshall C. Johnson, Marcelo Tala Pinto, Jonathan Crass +59

The paper describes the commissioning and first on‑sky performance of iLocater, a high‑resolution near‑infrared spectrograph on the Large Binocular Telescope, demonstrating its abi…

#near-infrared spectroscopy#extreme precision radial velocity#high-resolution spectrograph#adaptive optics
astro-ph.IM2024

Performance of the Nonlinear Curvature Wavefront Sensor as a Function of Scintillation Strength

Stanimir Letchev, Justin R. Crepp, Caleb G. Abbott +3

Local amplitude aberrations caused by scintillation can impact the reconstruction process of a wavefront sensor (WFS) by inducing a spatially non-uniform intensity at the pupil pla…

physics.optics2026

Phase Retrieval using Nonlinear Curvature Sensing within Convergent Beams

Justin R. Crepp, Caleb G. Abbott, James Smous +2

Path-length diversity methods may be used for adaptive optics (AO) systems to retrieve phase and amplitude information by measuring intensity across multiple planes. Observations t…

astro-ph.IM2022

The iLocater cryostat and thermal control system: enabling extremely precise radial velocity measurements for diffraction-limited spectrographs

Jonathan Crass, Nandini Sadagopan, Matthew Misch +10

Extremely precise radial velocity (EPRV) measurements are critical for characterizing nearby terrestrial worlds. EPRV instrument precisions of $σ_{\mathrm{RV}} = 1-10\,\mathrm{cm/…

astro-ph.IM2024

Resolving the Young 2 Cygni Run-away Star into a Binary using iLocater

Justin R. Crepp, Jonathan Crass, Andrew J. Bechter +30

Precision radial velocity (RV) spectrographs that use adaptive optics (AO) show promise to advance telescope observing capabilities beyond those of seeing-limited designs. We are b…

astro-ph.IM2020

Final Design and On-Sky Testing of the iLocater SX Acquisition Camera: Broadband Single-Mode Fiber Coupling

Jonathan Crass, Andrew Bechter, Brian Sands +22

Enabling efficient injection of light into single-mode fibers (SMFs) is a key requirement in realizing diffraction-limited astronomical spectroscopy on ground-based telescopes. SMF…