The possibility of detecting planets in the Andromeda Galaxy

Abstract

The Angstrom Project is using a global network of 2m-class telescopes to conduct a high cadence pixel microlensing survey of the bulge of the Andromeda Galaxy (M31), with the primary aim of constraining its underlying bulge mass distribution and stellar mass function. Here we investigate the feasibility of using such a survey to detect planets in M31. We estimate the efficiency of detecting signals for events induced by planetary systems as a function of planet/star mass ratio and separation, source type and background M31 surface brightness. We find that for planets of a Jupiter-mass or above that are within the lensing zone (~1 -3 AU) detection is possible above 3 $\sigma$, with detection efficiencies ~3% for events associated with giant stars, which are the typical source stars of pixel-lensing surveys. A dramatic improvement in the efficiency of ~40 -- 60% is expected if follow-up observations on an 8m telescope are made possible by a real-time alert system.

total 8 pages, including 8 figures, ApJ, submitted

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Cited by in corpus (11)

• Pixel-lensing as a way to detect extrasolar planets in M31
• Gas Giants in Hot Water: Inhibiting Giant Planet Formation and Planet Habitability in Dense Star Clusters Through Cosmic Time
• M31 pixel lensing event OAB-N2: a study of the lens proper motion
• Pixel lensing: Microlensing towards M31
• Expansion of the Planet Detection Channels in Next-Generation Microlensing Surveys
• Search for exoplanets in M31 with pixel-lensing and the PA-99-N2 event revisited
• Planetary microlensing signals from the orbital motion of the source star around the common barycentre
• The Angstrom Project Alert System: real-time detection of extragalactic microlensing
• Exoplanetary searches with gravitational microlensing: polarization issues
• Detection of planets in extremely weak central perturbation microlensing events via next-generation ground-based surveys
• Microlensing and Variability in the Bulge of M31