Candidate strongly lensed type Ia supernovae in the Zwicky Transient Facility archive

Abstract

Gravitationally lensed type Ia supernovae (glSNe Ia) are unique astronomical tools that can be used to study cosmological parameters, distributions of dark matter, the astrophysics of the supernovae, and the intervening lensing galaxies themselves. A small number of highly magnified glSNe Ia have been discovered by ground-based telescopes such as the Zwicky Transient Facility (ZTF), but simulations predict that a fainter population may also exist. We present a systematic search for glSNe Ia in the ZTF archive of alerts distributed from June 1 2019 to September 1 2022. Using the AMPEL platform, we developed a pipeline that distinguishes candidate glSNe Ia from other variable sources. Initial cuts were applied to the ZTF alert photometry before forced photometry was obtained for the remaining candidates. Additional cuts were applied to refine the candidates based on their light curve colours, lens galaxy colours, and the resulting parameters from fits to the SALT2 SN Ia template. The candidates were also cross-matched with the DESI spectroscopic catalogue. Seven transients were identified that had an associated galaxy DESI redshift, which we present as glSN Ia candidates. Although superluminous supernovae (SLSNe) cannot be fully rejected as contaminants, two events, ZTF19abpjicm and ZTF22aahmovu, are significantly different from typical SLSNe and their light curves can be modelled as two-image glSN Ia systems. From this two-image modelling, we estimate time delays of 22 $\pm$ 3 and 34 $\pm$ 1 days for the two events, respectively, which suggests that we have uncovered a population of glSNe Ia with longer time delays. The pipeline is currently being applied to the live ZTF alert stream to identify and follow-up future candidates while active, and it could be the foundation for glSNe Ia searches in future surveys, such as the Rubin Observatory Legacy Survey of Space and Time.

29 pages, 15 figures. Accepted in A&A

References in corpus (42)

• The Zwicky Transient Facility: System Overview, Performance, and First Results
• The propagation of uncertainties in stellar population synthesis modeling I: The relevance of uncertain aspects of stellar evolution and the IMF to the derived physical properties of galaxies
• The Zwicky Transient Facility: Data Processing, Products, and Archive
• The Zwicky Transient Facility: Science Objectives
• Stellar Population Inference with Prospector
• The type Ia supernova SNLS-03D3bb from a super-Chandrasekhar-mass white dwarf star
• Overview of the Instrumentation for the Dark Energy Spectroscopic Instrument
• The Zwicky Transient Facility: Surveys and Scheduler
• unWISE: unblurred coadds of the WISE imaging
• The Early Data Release of the Dark Energy Spectroscopic Instrument
• Multiple Images of a Highly Magnified Supernova Formed by an Early-Type Cluster Galaxy Lens
• The Zwicky Transient Facility: Observing System
• The Zwicky Transient Facility Bright Transient Survey. II. A Public Statistical Sample for Exploring Supernova Demographics
• DESI Bright Galaxy Survey: Final Target Selection, Design, and Validation
• The Spectroscopic Data Processing Pipeline for the Dark Energy Spectroscopic Instrument
• The WISE AGN Catalog
• Spectroscopy of superluminous supernova host galaxies. A preference of hydrogen-poor events for extreme emission line galaxies
• The Robotic Multi-Object Focal Plane System of the Dark Energy Spectroscopic Instrument (DESI)
• Black hole masses of tidal disruption event host galaxies
• The Zwicky Transient Facility Alert Distribution System
• Nested Sampling with Normalising Flows for Gravitational-Wave Inference
• The Palomar Transient Factory Core-Collapse Supernova Host-Galaxy Sample. I. Host-Galaxy Distribution Functions and Environment-Dependence of CCSNe
• Candidate Tidal Disruption Event AT2019fdr Coincident with a High-Energy Neutrino
• WISE x SuperCOSMOS photometric redshift catalog: 20 million galaxies over 3pi steradians
• Detection of the Gravitational Lens Magnifying a Type Ia Supernova
• All-purpose, all-sky photometric redshifts for the Legacy Imaging Surveys Data Release 8
• How to Find Gravitationally Lensed Type Ia Supernovae
• Redback: A Bayesian inference software package for electromagnetic transients
• Automated physical classification in the SDSS DR10. A catalogue of candidate Quasars
• Uncovering a population of gravitational lens galaxies with magnified standard candle SN Zwicky
• Lensed Type Ia Supernova "Encore" at z=2: The First Instance of Two Multiply-Imaged Supernovae in the Same Host Galaxy
• The Hubble constant from strongly lensed supernovae with standardizable magnifications
• High-redshift supernova rates measured with the gravitational telescope A1689
• A Systematic Study of Ia-CSM Supernovae from the ZTF Bright Transient Survey
• Supernova SN 2012dn: A spectroscopic clone of SN 2006gz
• LensWatch: I. Resolved HST Observations and Constraints on the Strongly-Lensed Type Ia Supernova 2022qmx ("SN Zwicky")
• ASASSN-15hy: an under-luminous, red 03fg-like type Ia supernova
• Be It Unresolved: Measuring Time Delays from Lensed Supernovae
• Using 1991T/1999aa-like Type Ia Supernovae as Standardizable Candles
• Testing for redshift evolution of Type Ia supernovae using the strongly lensed PS1-10afx at $z=1.4$
• A search for gravitationally lensed supernovae within the Zwicky Transient Facility public survey
• A targeted search for strongly lensed supernovae with the Las Cumbres Observatory

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