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arXiv · 1001.4342

Search for exoplanets in M31 with pixel-lensing and the PA-99-N2 event revisited

G. Ingrosso·S. Calchi-Novati·F. De Paolis·Ph. Jetzer·A. A. Nucita·A. F. Zakharov
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Abstract

Several exoplanets have been detected towards the Galactic bulge with the microlensing technique. We show that exoplanets in M31 may also be detected with the pixel-lensing method, if telescopes making high cadence observations of an ongoing microlensing event are used. Using a Monte Carlo approach we find that the mean mass for detectable planetary systems is about $2 M_{\rm {J}}$. However, even small mass exoplanets ($M_{\rm P} < 20 M_{\oplus}$) can cause significant deviations, which are observable with large telescopes. We reanalysed the POINT-AGAPE microlensing event PA-99-N2. First, we test the robustness of the binary lens conclusion for this light curve. Second, we show that for such long duration and bright microlensing events, the efficiency for finding planetary-like deviations is strongly enhanced with respect to that evaluated for all planetary detectable events.

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G. Ingrosso, S. Calchi-Novati, F. De Paolis, Ph. Jetzer, A. A. Nucita, A. F. Zakharov. 2010-01-25. Search for exoplanets in M31 with pixel-lensing and the PA-99-N2 event revisited. https://doi.org/10.1007/s10714-010-0942-3

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