4 research outputs found
Precise Stellar Radial Velocities of an M Dwarf with a Michelson Interferometer and a Medium-resolution Near-infrared Spectrograph
Precise near-infrared radial velocimetry enables efficient detection and
transit verification of low-mass extrasolar planets orbiting M dwarf hosts,
which are faint for visible-wavelength radial velocity surveys. The TripleSpec
Exoplanet Discovery Instrument, or TEDI, is the combination of a variable-delay
Michelson interferometer and a medium-resolution (R=2700) near-infrared
spectrograph on the Palomar 200" Hale Telescope. We used TEDI to monitor GJ
699, a nearby mid-M dwarf, over 11 nights spread across 3 months. Analysis of
106 independent observations reveals a root-mean-square precision of less than
37 m/s for 5 minutes of integration time. This performance is within a factor
of 2 of our expected photon-limited precision. We further decompose the
residuals into a 33 m/s white noise component, and a 15 m/s systematic noise
component, which we identify as likely due to contamination by telluric
absorption lines. With further development this technique holds promise for
broad implementation on medium-resolution near-infrared spectrographs to search
for low-mass exoplanets orbiting M dwarfs, and to verify low-mass transit
candidates.Comment: 55 pages and 13 figures in aastex format. Accepted by PAS