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The eclipsing white dwarf plus main-sequence binary NN Serpentis provides one of the most convincing cases for the existence of circumbinary planets around evolved binaries. The exquisite timing precision provided by the deep eclipse of the white dwarf has revealed complex variations in the eclipse arrival times over the last few decades. These variations have been interpreted as the influence of two planets in orbit around the binary. Recent studies have proved that such a system is dynamically stable over the current lifetime of the binary. However, the existence of such planets is by no means proven and several alternative mechanisms have been proposed that could drive similar variations. One of these is apsidal precession, which causes the eclipse times of eccentric binaries to vary sinusoidally on many year timescales. In this paper we present timing data for the secondary eclipse of NN Ser and show that they follow the same trend seen in the primary eclipse times, ruling out apsidal precession as a possible cause for the variations. This result leaves no alternatives to the planetary interpretation for the observed period variations, although we still do not consider their existence as proven. Our data limits the eccentricity of NN Ser to e<0.001. We also detect a 3.3+/-1.0 second delay in the arrival times of the secondary eclipses relative to the best planetary model. This delay is consistent with the expected 2.84+/-0.04 second Romer delay of the binary, and is the first time this effect has been detected in a white dwarf plus M dwarf system.
With more than 80 transits observed in the CoRoT light curve with a cadence of 32 s, CoRoT-Exo-2b provides an excellent case to search for the secondary eclipse of the planet, with an expected signal of less than 10^-4 in relative flux. The activity
We present a hierarchical triple star system (KIC 9140402) where a low mass eclipsing binary orbits a more massive third star. The orbital period of the binary (4.98829 Days) is determined by the eclipse times seen in photometry from NASAs Kepler spa
The transiting planet CoRoT-1b is thought to belong to the pM-class of planets, in which the thermal emission dominates in the optical wavelengths. We present a detection of its secondary eclipse in the CoRoT white channel data, whose response functi
We utilize multi-dimensional simulations of varying equatorial jet strength to predict wavelength dependent variations in the eclipse times of gas-giant planets. A displaced hot-spot introduces an asymmetry in the secondary eclipse light curve that m
We report eclipse timing variation analyses of 26 compact hierarchical triple stars comprised of an eccentric eclipsing (inner) binary and a relatively close tertiary component found in the {em Kepler} field. We simultaneously fit the primary and sec