Qatar-1: indications for possible transit timing variations
Abstract
Aims: Variations in the timing of transiting exoplanets provide a powerful tool for detecting additional planets in the system. Thus, the aim of this paper is to discuss the plausibility of transit timing variations (TTVs) on the Qatar-1 system by means of primary transit light curves analysis. Furthermore, we provide an interpretation of the timing variation.
Methods: We observed Qatar-1 between March 2011 and October 2012 using the 1.2 m OLT telescope in Germany and the 0.6 m PTST telescope in Spain. We present 26 primary transits of the hot Jupiter Qatar-1b. In total, our light curves cover a baseline of 18 months.
Results: We report on indications for possible long-term TTVs. Assuming that these TTVs are true, we present two different scenarios that could explain them. Our reported ~190 days TTV signal can be reproduced by either a weak perturber in resonance with Qatar-1b, or by a massive body in the brown dwarf regime. More observations and radial velocity monitoring are required to better constrain the perturber's characteristics. We also refine the ephemeris of Qatar-1b, which we find to be T0 = 2456157.42204 ± 0.0001 BJDTDB and P = 1.4200246 ± 0.0000007 days, and improve the system orbital parameters.
- Publication:
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Astronomy and Astrophysics
- Pub Date:
- July 2013
- DOI:
- 10.1051/0004-6361/201321407
- arXiv:
- arXiv:1309.1457
- Bibcode:
- 2013A&A...555A..92V
- Keywords:
-
- methods: data analysis;
- methods: observational;
- techniques: photometric;
- eclipses;
- Astrophysics - Earth and Planetary Astrophysics
- E-Print:
- doi:10.1051/0004-6361/201321407