Improved Theoretical Predictions of Microlensing Rates for the Detection of Primordial Black Hole Dark Matter

Abstract

Primordial Black Holes (PBHs) remain a Dark Matter (DM) candidate of the Standard Model of Particle Physics. Previously, we proposed a new method of constraining the remaining PBH DM mass range using microlensing of stars monitored by NASA's Kepler mission. We improve this analysis using a more accurate treatment of the population of the Kepler source stars, their variability and limb-darkening. We extend the theoretically detectable PBH DM mass range down to $2\times10^{-10} M_\sun$, two orders of magnitude below current limits and one third order of magnitude below our previous estimate. We address how to extract the DM properties such as mass and spatial distribution if PBH microlensing events were detected. We correct an error in a well-known finite-source limb-darkening microlensing formula and also examine the effects of varying the light curve cadence on PBH DM detectability. We also introduce an approximation for estimating the predicted rate of detection per star as a function of the star's properties, thus allowing for selection of source stars in future missions, and extend our analysis to planned surveys, such as WFIRST.

References in corpus (1)

• Dark Matter Candidates from Particle Physics and Methods of Detection

Cited by in corpus (7)

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• Experimental Limits on Primordial Black Hole Dark Matter from the First Two Years of Kepler Data
• Constraining Primordial Black-Hole Bombs through Spectral Distortions of the Cosmic Microwave Background
• On the wave optics effect on primordial black hole constraints from optical microlensing search
• Adiabatic contraction revisited: implications for primordial black holes