Planetary Microlensing Perturbations: True Planets or Binary Sources?
| dc.creator | Gaudi, B. Scott | |
| dc.date | 1997-06-26 | |
| dc.date.accessioned | 2026-07-07T02:23:42Z | |
| dc.date.available | 2026-07-07T02:23:42Z | |
| dc.description | A planetary microlensing event is characterized by a short-lived perturbation to the standard Paczyński curve. Planetary perturbations typically last from a few hours to a day, and have maximum amplitudes, $\dmax$, of $5-20%$ of the standard curve. There exist a subset of binary-source events that can reproduce these main features, and thus masquerade as planetary events. These events require a binary source with a small flux ratio, $\epsil \sim 10^{-2}-10^{-4}$, and a small impact parameter for the fainter source, $β_2 \lsim \epsil / \dmax$. The detection probability of events of this type is $\sim β_2$, and can be as high as $\sim 30%$; this is comparable to planetary detection rates. Thus a sample of planetary-like perturbations could be seriously contaminated by binary-source events, and there exists the possibility that completely meaningless physical parameters would be derived for any given perturbation. Here I derive analytic expressions for a binary-source event in the extreme flux ratio limit, and use these to demonstrate the basic degeneracy between binary source and planet perturbations. I describe how the degeneracy can be broken by dense and accurate sampling of the perturbation, optical/infrared photometry, or spectroscopic measurements. | |
| dc.description | 21 pages, 4 embedded figures, TeX, uses phyzzx | |
| dc.identifier | https://arxiv.org/abs/astro-ph/9706268 | |
| dc.identifier | http://arxiv.org/abs/astro-ph/9706268 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/11347 | |
| dc.subject | Astrophysics | |
| dc.title | Planetary Microlensing Perturbations: True Planets or Binary Sources? | |
| dc.type | text |