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arXiv · 1001.2105

Detection of Exoplanets in M31 with Pixel-Lensing: The Event Pa-99-N2 Case

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

We show that exoplanets in the M31 galaxy may be detected with the pixel-lensing method by using telescopes making high cadence observations of an ongoing microlensing event. Although the mean mass for detectable exoplanets is about $2 M_{\rm {J}}$, 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.

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G. Ingrosso, F. De Paolis, S. Calchi Novati, Ph. Jetzer, A. A. Nucita, A. F. Zakharov. 2010-01-13. Detection of Exoplanets in M31 with Pixel-Lensing: The Event Pa-99-N2 Case. https://arxiv.org/abs/1001.2105

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