  KOI-13 was presented by the Kepler team as a candidate for having a giant
planet - KOI-13.01, with orbital period of 1.7 d and transit depth of ~0.8%. We
have analyzed the Kepler Q2 data of KOI-13, which was publicly available at the
time of the submission of this paper, and derived the amplitudes of the
beaming, ellipsoidal and reflection modulations: 8.6 +/- 1.1, 66.8 +/- 1.6 and
72.0 +/- 1.5 ppm (parts per million), respectively. After the paper was
submitted, Q3 data were released, so we repeated the analysis with the newly
available light curve. The results of the two quarters were quite similar. From
the amplitude of the beaming modulation we derived a mass of 10 +/- 2 M_Jup for
the secondary, suggesting that KOI-13.01 was a massive planet, with one of the
largest known radii. We also found in the data a periodicity of unknown origin
with a period of 1.0595 d and a peak-to-peak modulation of ~60 ppm. The light
curve of Q3 revealed a few more small-amplitude periodicities with similar
frequencies. It seemed as if the secondary occultation of KOI-13 was slightly
deeper than the reflection peak-to-peak modulation by 16.8 +/- 4.5 ppm. If
real, this small difference was a measure of the thermal emission from the
night side of KOI-13.01. We estimated the effective temperature to be 2600 +/-
150 K, using a simplistic black-body emissivity approximation. We then derived
the planetary geometrical and Bond albedos as a function of the day-side
temperature. Our analysis suggested that the Bond albedo of KOI-13.01 might be
substantially larger than the geometrical albedo.
