Difference Image Analysis of Galactic Microlensing II. Microlensing Events
Abstract
The MACHO collaboration has been carrying out Difference Image Analysis (DIA) since 1996 with the aim of increasing the sensitivity to the detection of gravitational microlensing. This is a preliminary report on the application of DIA to galactic bulge images in one field. We show how the DIA technique significantly increases the number of detected lensing events, by removing the positional dependence of traditional photometry schemes and lowering the microlensing event detection threshold. This technique, unlike PSF photometry, gives the unblended colours and positions of the microlensing source stars. We present a set of criteria for selecting microlensing events from objects discovered with this technique. The 16 pixel and classical microlensing events discovered with the DIA technique are presented.
Cite
@article{arxiv.astro-ph/9903219,
title = {Difference Image Analysis of Galactic Microlensing II. Microlensing Events},
author = {C. Alcock and R. A. Allsman and D. Alves and T. S. Axelrod and A. C. Becker and D. P. Bennett and K. H. Cook and A. J. Drake and K. C. Freeman and K. Griest and M. J. Lehner and S. L. Marshall and D. Minniti and B. A. Peterson and M. R. Pratt and P. J. Quinn and C. W. Stubbs and W. Sutherland and A. Tomaney and T. Vandedei and D. L. Welch},
journal= {arXiv preprint arXiv:astro-ph/9903219},
year = {2009}
}
Comments
13 pages, 6 figures, uses AAS LaTEX 4.0, To appear in ApJS