Paper 13094-166
The Lowell Observatory Solar Telescope: A fiber feed into the EXtreme PREcision Spectrometer
Abstract
The signal induced by a temperate, terrestrial planet orbiting a Sun-like star is an order of magnitude smaller than the host stars’ intrinsic variability. Understanding stellar activity is, therefore, a fundamental obstacle in confirming the smallest exoplanets. We present the Lowell Observatory Solar Telescope (LOST), a solar feed for the EXtreme PREcision Spectrometer (EXPRES) at the 4.3-m Lowell Discovery Telescope (LDT). EXPRES is one of the newest high-resolution spectrographs that accurately measure extreme radial velocity. With LOST/EXPRES, we observe disk-integrated sunlight autonomously throughout the day. In clear conditions, we achieve a R ∼ 137, 500 optical spectrum of the Sun with a signal-to-noise of 500 in ∼ 150s. Data is reduced using the standard EXPRES pipeline with minimal modification to ensure the data are comparable to the observations of other stars with the LDT. During the first three years of operation, we find a daily RMS of 71cm/s. Additionally, having two EPRV spectrometers located in Arizona gives us an unprecedented opportunity to benchmark the performance of these planet-finders. We find a RMS of just 55cm/s when comparing data taken simultaneously with EXPRES and NEID.
Presenter
Lowell Observatory (United States)
Dr. Joe Llama is an Astronomer at Lowell Observatory specializing in the detection and characterization of Earth-sized exoplanets using extreme precision radial velocity (EPRV). In particular, Dr. Llama is interested in understanding the impact stellar activity has on our ability to detect the minuscule Doppler Shift induced by Earth-mass planets orbiting within the habitable zone of their parent star. He is the PI of the Lowell Observatory Solar Telescope (LOST) which he uses to observe the Sun-as-a-disk-integrated-star with the EXtreme PREcision Spectrograph (EXPRES) to better understand how stellar activity manifests in our observations of other stars.