| Author(s) and Co-Author(s) with Affiliation: Prajakta Mane(University of Pittsburgh, Pittsburgh - 15260, US), Surhud More(Inter-University Centre for Astronomy and Astrophysics, Pune - 411007, India), Anupreeta More(Inter-University Centre for Astronomy and Astrophysics, Pune - 411007, India), Anindya Ganguly(Inter-University Centre for Astronomy and Astrophysics, Pune - 411007, India), Michael Wood Vasey(University of Pittsburgh, Pittsburgh - 15260, US), Arun Kannawadi(Duke University, Durham - 27708, US), Jim Chiang(SLAC National Accelerator Laboratory, Menlo Park - 94025, US) |
| Abstract: Gravitationally lensed Type Ia Supernovae (SNe Ia) are uniquely suited to address the Hubble constant problem in cosmology. In addition to obtaining accurate time delays, the standard candle nature of SNe Ia also provides additional constraints on the lens model parameters. Finding such supernovae in the ground-based imaging data from the Rubin Observatory is a challenge. The multiple images of a lensed SN Ia can be identified as newly appearing sources in the difference imaging. However, these lensed supernova images are expected to be unresolved for a majority of the lenses, making it very difficult to identify them from a million nightly alerts. We evaluate the performance of the LSST Science Pipelines’ Difference Image Analysis and Association pipeline on real HSC and DP1 images in identifying the injected synthetic lensed SNe Ia. We expect several of these unresolved sources to appear extended in the differece images, and study the measured properties of DI sources that estimate their shapes to find such markers of lensing. We also study whether using any of the DI pipeline flags can help in reducing contamination from unlensed transients. We also run association on the DI sources, and identify and classify various kinds of mis-associations that can impact their identification. Finally, we show the effectiveness of the color-magnitude criterion for identifying lensed SNe Ia with measured photometry of DI sources. |
