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General Relativity and Gravitation

, Volume 43, Issue 4, pp 1047–1060 | Cite as

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

  • Gabriele Ingrosso
  • Sebastiano Calchi Novati
  • Francesco De Paolis
  • Philippe Jetzer
  • Achille Nucita
  • Alexander Zakharov
Research Article

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 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.

Keywords

Microlensing Exoplanets Spiral galaxies: M31 

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Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  • Gabriele Ingrosso
    • 1
  • Sebastiano Calchi Novati
    • 2
  • Francesco De Paolis
    • 1
  • Philippe Jetzer
    • 3
  • Achille Nucita
    • 4
  • Alexander Zakharov
    • 5
    • 6
  1. 1.Dipartimento di FisicaUniversità del Salento, INFN Sezione di LecceLecceItaly
  2. 2.Dipartimento di FisicaUniversità di Salerno, INFN Sezione di NapoliBaronissiItaly
  3. 3.Institute for Theoretical PhysicsUniversity of ZürichZurichSwitzerland
  4. 4.XMM-Newton Science Operations Centre, ESAC, ESAMadridSpain
  5. 5.Institute of Theoretical and Experimental PhysicsMoscowRussia
  6. 6.Bogoliubov Laboratory of Theoretical PhysicsJoint Institute for Nuclear ResearchDubnaRussia

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