Exoplanets & Stellar Populations Group

TASTE project

Nascimbeni et al. 2011, A&A 527, 85

A promising method to detect Earth-sized exoplanets is the so-called Transit Time Variation analysis (TTV). By monitoring a known transiting planet with high-precision photometry, the central instant T₀ of each individual transit can be estimated. The gravitational perturbation of a previously unknown third body, which is not necessarily transiting, can cause a significant variation of the orbital period P (Holman & Murray 2005, Science 307, 1288). The effect is dependent on the mass of the third body, and is greatly increased if the perturber is locked in a low-order mean-motion resonance with the transiting planet (Agol et al. 2005, MNRAS 359, 567), resulting in typical amplitudes of 10-100 s or even more. The TTV technique has been exploited and already gave amazing results on a large number of planetary systems discovered by the Kepler mission, the most representative being Kepler-11 (Lissauer et al. 2011, Nature, 470, 53). The presence of an exomoon, which makes the planet oscillate around the planet-satellite barycenter along its path, may also cause a periodic TDV (Transit Duration Variation; Kipping 2009a, MNRAS, 392, 181) as well as a TTV, which can reach an amplitude of 10-15 s in the case of 1 M_Earth Hill-stable exomoon around a Neptunian transiting planet.
The Asiago Search for Transit timing variation of Exoplanets (TASTE) is a project started by our group in 2009 to search for TTVs and TDVs with several ground-based, medium-class facilities on a sample of carefully selected targets (Nascimbeni et al. 2011, A&A 527, 85). The involved instruments includes the Copernico (182cm) and Schmidt telescopes at the Asiago Astrophysical Observatory (operated by INAF - Istituto Nazionale di Astrofisica), TCS, IAC-80, STELLA-I at the Teide Observatory, and larger telescopes such as NOT and TNG at the Roque de Los Muchachos Observatory (Canary Islands). We chose to optimize every task from the observation/calibration setup to the data extraction with a fully home-made software pipeline. An important added value of our project is the opportunity to perform a long-term photometric follow-up of our targets, leading to an extremely precise characterization of those systems.
For more information about the project and our papers, please contact Valerio Nascimbeni or Valentina Granata.

Related papers to TASTE project:

• Nascimbeni et al. (2011a) A&A 527, 85
• Nascimbeni et al. (2011b) A&A 532, 24
• Nascimbeni et al. (2013) A&A 549, 30
• Granata et al. (2014) AN 335, 797

Click on the button to access TASTE database (restricted access only to ESPG Members):

Below you can find the list of known extrasolar planets observed within TASTE project. Click on the exoplanet name to access to the relative light curve.

Name	Telescope(s)	References
HAT-P-3b	Copernico 182cm	Nascimbeni et al. (2011a)
HAT-P-13b	Copernico 182cm	Nascimbeni et al. (2011b)
HAT-P-14b	Copernico 182cm	Nascimbeni et al. (2011a)
HAT-P-20b	Copernico 182cm	Granata et al. (2014)
WASP-1b	Copernico 182cm	Granata et al. (2014)
WASP-3b	Copernico 1.82m, IAC 0.80m, UDEM 0.36m	Nascimbeni et al. (2013)