Enabling Early Transient Discovery in LSST via Difference Imaging with DECam
Abstract
We present SLIDE, a pipeline that enables transient discovery in data from the Vera C. Rubin Observatory's Legacy Survey of Space and Time (LSST), using archival images from the Dark Energy Camera (DECam) as templates for difference imaging. We apply this pipeline to the recently released Data Preview 1 (DP1; the first public release of Rubin commissioning data) and search for transients in the resulting difference images. The image subtraction, photometry extraction, and transient detection are all performed on the Rubin Science Platform. We demonstrate that SLIDE effectively extracts clean photometry by circumventing poor or missing LSST templates. We identified 29 previously unreported transients, 12 of which would not have been detected based on the DP1 DiaObject catalog. SLIDE will be especially useful for transient analysis in the early years of LSST, when template coverage will be largely incomplete or when templates may be contaminated by transients present at the time of acquisition. We present multiband light curves for a sample of known transients, along with new transient candidates identified through our search. Finally, we discuss the prospects of applying this pipeline during the main LSST survey. Our pipeline is broadly applicable and will support studies of all transients with slowly evolving phases.
Cite
@article{arxiv.2507.22156,
title = {Enabling Early Transient Discovery in LSST via Difference Imaging with DECam},
author = {Yize Dong and Kaylee de Soto and V. Ashley Villar and Anya Nugent and Alex Gagliano and K. Azalee Bostroem and Anastasia Alexov and Éric Aubourg and Farrukh Azfar and Alexandre Boucaud and Andrew Bradshaw and Johann Cohen-Tanugi and Sylvie Dagoret-Campagne and Phil N. Daly and Felipe Daruich and Peter E. Doherty and Holger Drass and Orion Eiger and Leanne P. Guy and Patrick A. Hascall and Željko Ivezić and Fabrice Jammes and M. James Jee and Tim Jenness and Steven M. Kahn and Yijung Kang and Lee S. Kelvin and Ivan V. Kotov and Gábor Kovács and Laurent Le Guillou and Shuang Liang and Mostafa Lutfi and Morgan May and Guillem Megias Homar and Marc Moniez and Freddy Muñoz Arancibia and Erfan Nourbakhsh and Hye Yun Park and John R. Peterson and Andrés A. Plazas Malagón and Daniel Polin and Bruno C. Quint and Tiago Ribeiro and Vincent J. Riot and Cécile Roucelle and Bruno O. Sánchez and David Sanmartim and Jacques Sebag and Nima Sedaghat and Richard A. Shaw and Alysha Shugart and Ioana Sotuela Elorriaga and Krzysztof Suberlak and John D. Swinbank and Sandrine Thomas and J. Anthony Tyson and Wouter van Reeven and Charlotte Ward and Christopher Z. Waters and Oliver Wiecha and W. M. Wood-Vasey},
journal= {arXiv preprint arXiv:2507.22156},
year = {2025}
}
Comments
accepted for publication in ApJL; SLIDE is available on GitHub: https://github.com/yizedong/SLIDE