Using LSST Microlensing to Constrain Dark Compact Objects in Spherical and Disk Configurations

Abstract

The Legacy Survey of Space and Time (LSST) with the Vera Rubin Observatory will provide strong microlensing constraints on dark compact objects (DCOs) in our Galaxy. However, most current forecasts limit their analysis to Primordial Black Holes (PBH). It is unclear how well LSST microlensing will be able to constrain alternative models of DCOs with different Galactic spatial profile distributions at a subdominant DM fraction. In this work, we investigate how well LSST microlensing will constrain spherical or disk-like Galactic spatial distributions of DCOs, taking into account extended observing times, baryonic microlensing background, and sky distribution of LSST sources. These extensions represent significant improvements over existing microlensing forecasts in terms of both accuracy and versatility. We demonstrate this power by deriving new LSST sensitivity projections for DCOs in spherical and disk-like distributions. We forecast that LSST will be able to constrain one solar mass PBHs to have a DM fraction under $4.1\times 10^{-4}$. One-solar-mass objects in a dark disk distribution with the same dimensions as the Galactic disk will be constrained below $3.1\times 10^{-4}$, while those with $m=10^5{M}_{\odot }$ will be constrained to below $3.4\times 10^{-5}$. We find that compressed dark disks can be constrained up to a factor of $\sim 10$ better than ones with identical dimensions to the baryonic disk. We also find that dark disks become less tightly constrained when they are tilted with respect to our own disk. This forecasting software is a versatile tool, capable of constraining any model of DCOs in the Milky Way with microlensing, and is made publically available at {https://github.com/HarrisonWinch96/DarkDisk_Microlensing}.

16 pages, 10 figures

References in corpus (16)

• galpy: A Python Library for Galactic Dynamics
• GW190521: A Binary Black Hole Merger with a Total Mass of $150M_{\odot }$
• Limits on the Macho Content of the Galactic Halo from the EROS-2 Survey of the Magellanic Clouds
• The Milky Way's circular velocity curve between 4 and 14 kpc from APOGEE data
• On the local dark matter density
• Subaru through a different lens: microlensing by extended dark matter structures
• Predictions of the Nancy Grace Roman Space Telescope Galactic Exoplanet Survey II: Free-Floating Planet Detection Rates
• Colorless Top Partners, a 125 GeV Higgs, and the Limits on Naturalness
• Primordial Black Hole Dark Matter and the LIGO/Virgo observations
• MOA-II Galactic Microlensing Constraints: The Inner Milky Way has a Low Dark Matter Fraction and a Near Maximal Disk
• Structure Formation and Exotic Compact Objects in a Dissipative Dark Sector
• Axion Stars in the Infrared Limit
• OGLE-2011-BLG-0265Lb: a Jovian Microlensing Planet Orbiting an M Dwarf
• The Blanco DECam Bulge Survey. I. The Survey Description and Early Results
• Primordial Black Hole Microlensing: The Einstein Crossing Time Distribution
• Massive Primordial Black Holes

Cited by in corpus (5)

• Direct Detection of Mirror Matter in Twin Higgs Models
• Dark Matter Candidates and Searches
• Baryogenesis through Asymmetric Reheating in the Mirror Twin Higgs
• Dark Classification Matters: Searching for Primordial Black Holes with LSST
• Dimming Starlight with Dark Compact Objects