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arXiv · 2109.13282

Out of One, Many: Distinguishing Time Delays from Lensed Supernovae

Mikhail Denissenya·Satadru Bag·Alex G. Kim·Eric V. Linder·Arman Shafieloo
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Abstract

Gravitationally lensed Type Ia supernovae are an emerging probe with great potential for constraining dark energy, spatial curvature, and the Hubble constant. The multiple images and their time delayed and magnified fluxes may be unresolved, however, blended into a single lightcurve. We demonstrate methods without a fixed source template matching for extracting the individual images, determining whether there are one (no lensing) or two or four (lensed) images, and measuring the time delays between them that are valuable cosmological probes. We find 100% success for determining the number of images for time delays greater than $\sim10$ days.

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Mikhail Denissenya, Satadru Bag, Alex G. Kim, Eric V. Linder, Arman Shafieloo. 2021-09-27. Out of One, Many: Distinguishing Time Delays from Lensed Supernovae. https://doi.org/10.1093/mnras/stac143

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