Microlensing Discovery and Characterization Efficiency in the Vera C. Rubin Legacy Survey of Space and Time

作     者：Abrams, Natasha S. Hundertmark, Markus P.G. Khakpash, Somayeh Street, Rachel A. Jones, R. Lynne Lu, Jessica R. Bachelet, Etienne Tsapras, Yiannis Moniez, Marc Blaineau, Tristan Di Stefano, Rosanne Makler, Martin Varela, Anibal Rabus, Markus 

作者机构：University of California Berkeley Astronomy Department BerkeleyCA94720 United States Zentrum für Astronomie der Universität Heidelberg Astronomisches Rechen-Institut Mönchhofstr. 12-14 Heidelberg69120 Germany Rutgers University Department of Physics & Astronomy 136 Frelinghuysen Rd PiscatawayNJ08854 United States  6740 Cortona Drive Suite 102 GoletaCA93117 United States Aerotek and Rubin Observatory TucsonAZ United States IPAC Caltech PasadenaCA91125 United States Université Paris-Saclay CNRS IN2P3 IJCLab France Harvard-Smithsonian Center for Astrophysics CambridgeMA02138 United States International Center for Advanced Studies Instituto de Ciencias Físicas ECyT-UNSAM & CONICET Buenos Aires San Martín1650 Argentina Centro Brasileiro de Pesquisas Físicas RJ Rio de Janeiro22290–180 Brazil Departamento de Matemática y Física Aplicadas Facultad de Ingeniería Universidad Católica de la Santísima Concepción Alonso de Rivera Concepción2850 Chile 

出 版 物：《arXiv》 (arXiv)

年 卷 期：2023年

核心收录：

主　　题：Stars 

摘      要：The Vera C. Rubin Legacy Survey of Space and Time will discover thousands of microlensing events across the Milky Way Galaxy, allowing for the study of populations of exoplanets, stars, and compact objects. We evaluate numerous survey strategies simulated in the Rubin Operation Simulations (OpSims) to assess the discovery and characterization efficiencies of microlensing events. We have implemented three metrics in the Rubin Metric Analysis Framework: a discovery metric and two characterization metrics, where one estimates how well the lightcurve is covered and the other quantifies how precisely event parameters can be determined. We also assess the characterizability of microlensing parallax, critical for detection of free-floating black hole lenses. We find that, given Rubin’s baseline cadence, the discovery and characterization efficiency will be higher for longer duration and larger parallax events. Microlensing discovery efficiency is dominated by the observing footprint, where more time spent looking at regions of high stellar density including the Galactic bulge, Galactic plane, and Magellanic clouds, leads to higher discovery and characterization rates. However, if the observations are stretched over too wide an area, including low-priority areas of the Galactic plane with fewer stars and higher extinction, event characterization suffers by 10%. This could impact exoplanet, binary star, and compact object events alike. We find that some rolling strategies (where Rubin focuses on a fraction of the sky in alternating years) in the Galactic bulge can lead to a 15-20% decrease in microlensing parallax characterization, so rolling strategies should be chosen carefully to minimize losses. © 2023, CC BY.