SOCHIAS Santiago, January - 09. Sergio Hoyer Miranda Departamento de Astronomía Universidad de Chile 1
Jan 04, 2016
SOCHIAS Santiago, January - 09.
Sergio Hoyer MirandaDepartamento de Astronomía
Universidad de Chile
1
Introduction
Ogle Candidates: OGLE-TR-182 OGLE-TR-131 OGLE-TR-109
Transit Timing Variations (TTV): OGLE-TR-111b
Ongoing Survey
SOCHIAS Santiago, January 09
Outline
Introduction
SOCHIAS Santiago, January 09
Exoplanetary Transits:
55 Transiting Planets has been detected.*
False Positives: - Statistics (photometric noise) - Instrumentals (errors in the photometry) - Astrophisycs ( binary or multiple systems )
Parameters we can infer:
Planet Radius, Orbital Period Orbit Inclination Tc,Td (with RV’s) Planet DENSITY
OGLE-TR-182
SOCHIAS Santiago, January 09
Data:GMOS - GEMINI South i ‘ & g’ band
i-band depth consistent with a Neptune-sizedTransiting planet.
OGLE-TR-182
SOCHIAS Santiago, January 09
Data:GMOS - GEMINI South i ‘ & g’ band
i-band depth consistent with a Neptune-sizedTransiting planet.
but…..
Eclipsing binary blended with a background reddened GIANT(Hoyer et al. 2007)
OGLE-TR-131
SOCHIAS Santiago, January 09
i band Light Curve
OGLE-TR-131
SOCHIAS Santiago, January 09
Using colors and low resolution spectra we conclude is a K2III
OGLE-TR-109
SOCHIAS Santiago, January 09
Another candidate:
Host Star: F0V Rstar = 1.5 Rsun fast rotating
Preliminary Results:
Rplanet = 1.3 Rjup
Inclination = 76 degrees
Period = 0.589 days
Transit Timing Variations
SOCHIAS Santiago, January 09
•In general Transit Detection is biased towards Giants Exoplanets. The smallest Transiting Planet detected until now is a Neptune-sized (HAT-P-11b) .
• TTVs: short term variations in Tc due gravitational interaction of the transiting planet with an unseen companion.
• TTVs could potentially detect down to Earth-mass planets from ground based telescopes.
• Also long term variations of Tc can be produce by the presence of another planet in the system (orbital precession)
*exoplanet.eu
Transit Timing Variations: OGLE-TR-111b
SOCHIAS Santiago, January 09
Possible origin of the variations:
• Exomoon ?
• Earth-mass planet perturbing the transiting planet ? Diaz, R. et al. 2008
Winn et al. 07
Minniti et al. 2007Our work
(Kipping, D. M. MNRAS 2009).
Transit Timing Variations: OGLE-TR-111b
SOCHIAS Santiago, January 09
3 transits were observed with FORS1 -2 in VLT
V-band Light Curve of OGLE-TR-111b
Transit Timing Variations
SOCHIAS Santiago, January 09
We are currently performing a search for unseen companions of transiting planets using TTV’s.
Recently obtained data from GEMINI Observatory, SOAR Telescope and CTIO 1 mt Telescope.
Working in a code to do Deconvolution Photometry.
Is also important to monitoring long term variations of the central Time of Transits.