6 research outputs found
WASP-14 b: Transit Timing analysis of 19 light curves
Although WASP-14 b is one of the most massive and densest exoplanets on a
tight and eccentric orbit, it has never been a target of photometric follow-up
monitoring or dedicated observing campaigns. We report on new photometric
transit observations of WASP-14 b obtained within the framework of "Transit
Timing Variations @ Young Exoplanet Transit Initiative" (TTV@YETI). We
collected 19 light-curves of 13 individual transit events using six telescopes
located in five observatories distributed in Europe and Asia. From light curve
modelling, we determined the planetary, stellar, and geometrical properties of
the system and found them in agreement with the values from the discovery
paper. A test of the robustness of the transit times revealed that in case of a
non-reproducible transit shape the uncertainties may be underestimated even
with a wavelet-based error estimation methods. For the timing analysis we
included two publicly available transit times from 2007 and 2009. The long
observation period of seven years (2007-2013) allowed us to refine the transit
ephemeris. We derived an orbital period 1.2 s longer and 10 times more precise
than the one given in the discovery paper. We found no significant periodic
signal in the timing-residuals and, hence, no evidence for TTV in the system.Comment: 12 pages, 10 figures, 7 table
YETI observations of the young transiting planet candidate CVSO 30 b
CVSO 30 is a unique young low-mass system, because, for the first time, a
close-in transiting and a wide directly imaged planet candidates are found
around a common host star. The inner companion, CVSO 30 b, is the first
possible young transiting planet orbiting a previously known weak-lined T-Tauri
star. With five telescopes of the 'Young Exoplanet Transit Initiative' (YETI)
located in Asia, Europe and South America we monitored CVSO 30 over three years
in a total of 144 nights and detected 33 fading events. In two more seasons we
carried out follow-up observations with three telescopes. We can confirm that
there is a change in the shape of the fading event between different
observations and that the fading event even disappears and reappears. A total
of 38 fading event light curves were simultaneously modelled. We derived the
planetary, stellar, and geometrical properties of the system and found them
slightly smaller but in agreement with the values from the discovery paper. The
period of the fading event was found to be 1.36 s shorter and 100 times more
precise than the previous published value. If CVSO 30 b would be a giant planet
on a precessing orbit, which we cannot confirm, yet, the precession period may
be shorter than previously thought. But if confirmed as a planet it would be
the youngest transiting planet ever detected and will provide important
constraints on planet formation and migration time-scales.Comment: 14 pages (20 with appendix), 7 figures (16 with appendix), 6 tables
(7 with appendix