Exoplanet Transits Registered at the Universidad de Monterrey Observatory. I. HAT-P-12b, HAT-P-13b, HAT-P-16b, HAT-P-23b, and WASP-10b

Abstract

Forty transits of the exoplanets HAT-P-12b, HAT-P-13b, HAT-P-16b, HAT-P-23b and WASP-10b were recorded with the 0.36m telescope at the Universidad de Monterrey Observatory. The images were captured with a standard Johnson-Cousins Rc and Ic and Sloan z' filters and processed to obtain individual light curves of the events. These light curves were successfully combined for each system to obtain a resulting one of higher quality, but with a slightly larger time sampling rate. A reduction by a factor of about four in per-point scatter was typically achieved, resulting in combined light curves with a scatter of ~1 mmag. The noise characteristics of the combined light curves were verified by comparing Allan variance plots of the residuals. The combined light curves for each system, along with radial velocity measurements from the literature when available, were modeled using a Monte Carlo method to obtain the essential parameters that characterize the systems. Our results for all these systems confirm the derived transit parameters (the planet-to-star radius ratio, R p /R * ; the scaled semi-major axis, a/R * ; the orbital inclination, i; in some cases the eccentricity, e; and argument of periastron of the orbit, ω), validating the methodology. This technique can be used by small college observatories equipped with modest-sized telescopes to help characterize known extrasolar planet systems. In some instances, the uncertainties of the essential transit parameters are also reduced. For HAT-P23b, in particular, we derive a planet size 4.5 ± 1.0% smaller. We also derive improved linear periods for each system, useful for scheduling observations.

Ground-based near-UV observations of 15 transiting exoplanets: constraints on their atmospheres and no evidence for asymmetrical transits

“…Spectroscopic and photometric studies have confirmed and improved upon the discovery values (Husnoo et al 2012;Ciceri et al 2013;Pearson et al 2014;Sada & Ramón-Fox 2016). It was found through Rossiter-McLaughlin observations (Moutou et al 2011) that HAT-P-16b's projected spin-orbit angle of λ = −10 • ± 16 • is aligned with the stellar spin axis.…”

“…Follow-up photometry studies have refined the planetary parameters of HAT-P-13b and searched for possible transit timing variations (Szabó et al 2010;Winn et al 2010;Fulton et al 2011;Pál et al 2011;Nascimbeni et al 2011;Southworth et al 2012a;Sada & Ramón-Fox 2016). In addition, Winn et al (2010) performed Rossiter-McLaughlin effect measurements of the system and found that HAT-P-13b is likely aligned (1.…”

The Continuing Search for Evidence of Tidal Orbital Decay of Hot Jupiters

“…Timing residuals for HAT-P-23 b. White points are data obtained and reanalyzed byMaciejewski et al (2018) and originally reported byBakos et al (2011);Ramón-Fox & Sada (2013);Ciceri et al (2015) andSada & Ramón-Fox (2016). Black points represent new data.…”

Radial Velocities from the N2K Project: Six New Cold Gas Giant Planets Orbiting HD 55696, HD 98736, HD 148164, HD 203473, and HD 211810

“…HIP 14810 b). For the transiting planets, we adopted the photometrically derived orbital periods for HAT-P-1 b (Johnson et al 2008), HAT-P-3 b (Chan et al 2011), HAT-P-12 b (Sada & Ramón-Fox 2016), HD 149026 b (Carter et al 2009), and XO-5 b (Smith 2015). For HAT-P-4 b and HD 17156 b, the radial velocities alone were sufficient to determine the orbital periods without any significant loss in precision.…”