TASTE - III. A homogeneous study of transit time variations in WASP-3b

The TASTE project is searching for low-mass planets with the Transit Timing Variation (TTV) technique, by gathering high-precision, short-cadence light curves for a selected sample of transit ing exoplanets. It has been claimed that the “hot Jupiter” WASP-3b could be perturbed by a second planet. Presenting eleven new light curves (secured at the IAC80 and UDEM telescopes) and re-analyzing thirty-eight archival light curves in a homogeneous way, we show that new data do not confirm the previously claimed TTV si gnal. However, we bring evidence that measurements are not consistent with a constant orbital period, though no significant pe riodicity can be detected. Additional dynamical modeling and follow-up observations are planned to constrain the properties of the p erturber or to put upper limits to it. We provide a refined ephemeris for WASP -3b and improved orbital/physical parameters. A contact eclipsing binary, serendipitously discovered among field stars, is re ported here for the first time.

[1]  B. A. McLeod,et al.  Deep MMT Transit Survey of the Open Cluster M37. II. Variable Stars , 2007, 0709.3484.

[2]  R. G. West,et al.  WASP-3b: a strongly irradiated transiting gas-giant planet , 2007, 0711.0126.

[3]  B. Scott Gaudi,et al.  Achieving Better Than 1 Minute Accuracy in the Heliocentric and Barycentric Julian Dates , 2010, 1005.4415.

[4]  E. Ford,et al.  QUANTIFYING THE CHALLENGES OF DETECTING UNSEEN PLANETARY COMPANIONS WITH TRANSIT TIMING VARIATIONS , 2010, 1011.1466.

[5]  E. K. Simpson,et al.  A TRANSIT TIMING ANALYSIS OF NINE RISE LIGHT CURVES OF THE EXOPLANET SYSTEM TrES-3 , 2009, 0905.4680.

[6]  C. Broeg,et al.  A new algorithm for differential photometry: computing anoptimum artificial comparison star , 2005 .

[7]  E. Agol,et al.  On detecting terrestrial planets with timing of giant planet transits , 2004 .

[8]  E. K. Simpson,et al.  Updated parameters for the transiting exoplanet WASP-3b using RISE, a new fast camera for the Liverpool Telescope , 2008, 0810.3526.

[9]  Ralph Neuhäuser,et al.  Transit timing variation and activity in the WASP-10 planetary system , 2010 .

[10]  John Southworth,et al.  Homogeneous studies of transiting extrasolar planets - III. Additional planets and stellar models , 2010, 1006.4443.

[11]  Akihiko Fukui,et al.  Erratum: Measurements of Transit Timing Variations for WASP-5b , 2010, 1009.5769.

[12]  Avi Shporer,et al.  LONG-TERM TRANSIT TIMING MONITORING AND REFINED LIGHT CURVE PARAMETERS OF HAT-P-13b , 2011, 1105.5599.

[13]  S. Poddan'y,et al.  Exoplanet Transit Database. Reduction and processing of the photometric data of exoplanet transits , 2009, 0909.2548.

[14]  Chen Cao,et al.  Observation and Research of the Transits of Extrasolar Planets , 2011 .

[15]  M. Zechmeister,et al.  The generalised Lomb-Scargle periodogram. A new formalism for the floating-mean and Keplerian periodograms , 2009, 0901.2573.

[16]  G. Laughlin,et al.  SYSTEMIC: A TESTBED FOR CHARACTERIZING THE DETECTION OF EXTRASOLAR PLANETS. II. NUMERICAL APPROACHES TO THE TRANSIT TIMING INVERSE PROBLEM , 2010, 1005.5396.

[17]  J. W. Lee,et al.  The Dwarf project: Eclipsing binaries – precise clocks to discover exoplanets , 2012, 1206.6709.

[18]  P. Maxted,et al.  Eclipsing binaries in open clusters. II. V453 Cyg in NGC 6871 , 2004, astro-ph/0403572.

[19]  John Southworth,et al.  Homogeneous studies of transiting extrasolar planets – I. Light-curve analyses , 2008, 0802.3764.

[20]  John Southworth,et al.  High-precision photometry by telescope defocussing - II. The transiting planetary system WASP-4 , 2009, 0907.3356.

[21]  M. R. Haas,et al.  A closely packed system of low-mass, low-density planets transiting Kepler-11 , 2011, Nature.

[22]  S. Roweis,et al.  ASTROMETRY.NET: BLIND ASTROMETRIC CALIBRATION OF ARBITRARY ASTRONOMICAL IMAGES , 2009, 0910.2233.

[23]  M. Skrutskie,et al.  The Two Micron All Sky Survey (2MASS) , 2006 .

[24]  Drake Deming,et al.  Extrasolar Planet Transits Observed at Kitt Peak National Observatory , 2012, 1202.2799.

[25]  D. Palmer A FAST CHI-SQUARED TECHNIQUE FOR PERIOD SEARCH OF IRREGULARLY SAMPLED DATA , 2009, 0901.1913.

[26]  D. Kipping Morphological Lightcurve Distortions due to Finite Integration Time , 2010, 1004.3741.

[27]  Frederic Pont,et al.  The effect of red noise on planetary transit detection , 2006, astro-ph/0608597.

[28]  Steve B. Howell,et al.  Handbook of CCD Astronomy: Contents , 2006 .

[29]  G. L. Wycoff,et al.  THE THIRD US NAVAL OBSERVATORY CCD ASTROGRAPH CATALOG (UCAC3) , 2004, 1003.2136.

[30]  M. Damasso,et al.  TASTE: The Asiago Search for Transit timing variations of Exoplanets I. Overview and improved parameters for HAT-P-3b and HAT-P-14b , 2010, 1011.6395.

[31]  Eric B. Ford,et al.  An Analysis of Jitter and Transit Timing Variations in the HAT-P-13 System , 2011 .

[32]  Ralph Neuhäuser,et al.  Transit timing variation in exoplanet WASP-3b , 2010 .

[33]  TASTE. II. A new observational study of transit time variations in HAT-P-13b ⋆ , 2011, 1105.4603.

[34]  A. Claret,et al.  A new non-linear limb-darkening law for LTE stellar atmosphere models III - Sloan filters: Calculations for –5.0 ≤ log [M/H] ≤ +1, 2000 K ≤ T$\mathsf{_{eff}}$ ≤ 50 000 K at several surface gravities , 2004 .

[35]  Steve B. Howell,et al.  Handbook of CCD Astronomy , 2000 .

[36]  S. Baliunas,et al.  A Prescription for period analysis of unevenly sampled time series , 1986 .

[37]  Avi Shporer,et al.  The Transit Light Curve Project. V. System Parameters and Stellar Rotation Period of HD 189733 , 2006, astro-ph/0612224.

[38]  Matthew J. Holman,et al.  The Use of Transit Timing to Detect Terrestrial-Mass Extrasolar Planets , 2005, Science.

[39]  Drake Deming,et al.  SYSTEM PARAMETERS, TRANSIT TIMES, AND SECONDARY ECLIPSE CONSTRAINTS OF THE EXOPLANET SYSTEMS HAT-P-4, TrES-2, TrES-3, and WASP-3 FROM THE NASA EPOXI MISSION OF OPPORTUNITY , 2010, 1011.2229.

[40]  John Asher Johnson,et al.  A PROGRADE, LOW-INCLINATION ORBIT FOR THE VERY HOT JUPITER WASP-3b , 2010, 1004.0692.