1. Characterization and selection of extrasolar planetary transit candidates Jose A. Gallardo N. P. Universidad Catolica de Chile, Santiago, Chile. Ecole Normale Superieure, Lyon, France. D. Minniti. P. Universidad Catolica de Chile.

2. Abstract  We want to select the planetary transit candidates delivered by the Optical Gravitational Lensing Experiment, OGLE, with the purpose of confirming them as extrasolar planets.  We use optical-IR photometry to estimate the stellar radius, and infer the planetary radius using the flux difference during the eclipse:

3. Observational Data  We have optical-IR photometry for 2 of the 3 fields observed by the OGLE project, CAR104 and CAR105.  Besides, we have low resolution spectra for 11 candidates in the fields.

4. Results  Using the VIK magnitudes, we can determine the spectral type for each candidate and derive the planetary radius.  All the candidates orbit main sequence Solar-type stars.

5. Results  Planetary radii for the 32 candidates found by the OGLE project. The majority of them have similar radii to HD209458b.

6. Results We have done a spectral classification for the most promising candidates. We show the comparison for the derived planetary radii using the VIK photometry.

7. Conclusions The VIK photometry allow to:  Estimate the stellar and planetary parameters.  Select the best planetary candidates.  Compare with the field stellar population.  We selected 11 promising candidates to be extrasolar planets. These, in the future, can be observed using high resolution spectra to measure radial velocities and constrain their masses.  Besides, we will do a theoretical study about the planetary atmosphere and compare with experimental data in collaboration with the ENS.