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Discovery of KPS-1b, a Transiting Hot-Jupiter, with an Amateur Telescope Setup (Abstract)

Volume 46 number 1 (2018)

Paul Benni
3 Concetta Circle, Acton, MA 01720; pbenni@verizon.net
Artem Burdanov, Vadim Krushinsky, Eugene Sokov
Space Sciences, Technologies and Astrophysics Research (STAR) Institute at the University of Liege; Artem.Burdanov@uliege.be

Abstract

(Abstract only) Using readily available amateur equipment, a wide-field telescope (Celestron RASA, 279 mm f/2.2) coupled with a SBIG ST-8300M camera was set up at a private residence in a fairly light polluted suburban town thirty miles outside of Boston, Massachusetts. This telescope participated in the Kourovka Planet Search (KPS) prototype survey, along with a MASTER-II Ural wide field telescope near Yekaterinburg, Russia. One goal was to determine if higher resolution imaging (~2 arcsec/pixel) with much lower sky coverage can practically detect exoplanet transits compared to the successful very wide-field exoplanet surveys (KELT, XO, WASP, HATnet, TrES, Qatar, etc.) which used an array of small aperture telescopes coupled to CCDs. The RASA telescope was pointed in the direction of HIP 53535 in Ursa Major and stared at the same point in the sky every clear night from January to April 2015. The image field of view was 1.67 × 1.25 degrees, with drift corrected by autoguiding. Image exposures were 50 seconds, taken with a Rc filter. About 115 hours of data were collected and processed by k-pipe data reduction pipeline software, consisting of sequential scripts for astrometry, instrumentation + differential photometry, and Box-fitting Least Squares (BLS) periodic transit search. Rather serendipitously, a 13.0 magnitude star (GSC0414800138, 2MASS 11004017+6457504 at coordinates R.A. 11h 00m 40.150s, Dec. +64° 57' 50.09") with periodic 10 mmag transits was detected. Follow-up with a narrow-field telescope (Celestron 1100 EdgeHD with SBIG ST-8XME camera) confirmed the transits were real and also achromatic with different filters. The Hot-Jupiter exoplanet was validated by RV measurements from the SOPHIE spectrograph. KPS-1b is similar in mass and radius to Jupiter (Mp = 1.14 ± 0.15 Mjup, Rp = 0.96 ± 0.10 Rjup) and has an orbital period of 1.70645 ± 0.00004 days. The host star is similar to our sun with mass and radius (M* = 0.93 ± 0.07 M, R* = 0.96 ± 0.08 R). From this initial success, the RASA telescope was upgraded with a larger CCD size camera, and multi-field imaging capability was added to increase the survey field of view to 8.0 × 2.5 degrees. With this setup, the Galactic Plane Exoplanet Survey (GPX) was started to survey high-density star fields of the Milky Way. Over the past year, several high quality exoplanet candidates were identified and are awaiting validation.