Detection of Exoplanet τ Boöetis b at the Simon Fraser University Trottier Teaching and Outreach Observatory

摘要

This is a report on the first detection of an exoplanet at Simon Fraser University's Trottier Observatory, based on radial-velocity (RV) measurements of the host star. The observatory is a teaching and public outreach facility with a 0.7-m aperture telescope under suburban skies. Measurements were done using a commercially manufactured, off-the-shelf, echelle spectrograph that is comparable in cost to high-end imaging systems, and that can be used to study a remarkable variety of astrophysical objects. The detected exoplanet is τ Boötis b, one of the first to be discovered by professionals, and is a "hot Jupiter." The exoplanet host star, τ Boötis A, is of magnitude 4.5, and spectral class F7V, and has one of the largest orbital RVs of any known host. Nevertheless, the Doppler shifts are tiny, and careful control of systematic uncertainties and sophisticated data-analysis methods are necessary for a successful detection. The RV was measured on ten nights, between mid-March 2016 and the end of June. The results cover most of the orbital cycle, and are in excellent agreement with the RV determined by professionals. This study provides one example of the many types of advanced spectroscopy projects that can be undertaken by undergraduate students at university teaching observatories, and by amateur astronomers, with increasingly affordable and easy-to-use equipment.