Follow-up of SN 2025wny VI: The Rate and Detectable Population of Strongly Lensed SLSNe-I in ZTF
Abstract
The Type I superluminous supernova (SLSN-I) SN 2025wny, multiply imaged by two foreground galaxies at zl = 0.375, is the first confirmed strongly lensed SLSN and the highest-redshift (zs = 2.015) multiply imaged supernova in a galaxy-scale configuration. We ask whether one discovery in seven years of Zwicky Transient Facility (ZTF) operations is consistent with expectations, and whether SN 2025wny is typical of the detectable population. We develop a forward simulation of strongly lensed SLSNe-I in ZTF, combining an empirically calibrated volumetric rate and luminosity function with a galaxy-scale deflector population, unresolved lensed light curves, and the actual ZTF observing history. We predict 0.037+0.022−0.020 yr−1, consistent with the rate of 0.14+0.31−0.11 yr−1 inferred from a single discovery in seven years of ZTF operations. Conditioning the simulation on discovery by ZTF corrects the magnifications and intrinsic luminosity of SN 2025wny for Malmquist- and magnification biases: the debiased peak bolometric luminosity, log10(Lbol,int/erg s−1) = 44.60+0.05−0.10, places it at the ∼97th percentile of the assumed SLSNe-I luminosity function. SN 2025wny is typical of the detectable population in redshift, luminosity, and magnification, but its 4.9'' image separation exceeds single-galaxy deflector expectations, implying our rates are conservative for wide-separation systems.
Related
- Follow-up of SN 2025wny IV: Photometric Time-delay Measurements of a Strongly Lensed Superluminous Supernova
- Follow-up of SN 2025wny III: Spectroscopic Time-delay Measurements of a Strongly Gravitationally Lensed Superluminous Supernova
- Follow-up of SN 2025wny V: Lens Modelling and Cosmography of a Strongly Lensed Superluminous Supernova at z = 2.015 using Space Data
- Extreme Stellar Death and Galaxy Feedback at z = 2: A Rest-frame Ultraviolet Characterization of the Strongly Lensed Superluminous Supernova 2025wny
- Follow-up of SN 2025wny I: Space-based Observations of the First Multiply-imaged Superluminous Supernova
BibTeX
@misc{hjortlund2026followup,
title = {{Follow-up of SN 2025wny VI: The Rate and Detectable Population of Strongly Lensed SLSNe-I in ZTF}},
author = {Jacob O. Hjortlund and Edvard Mörtsell and Ariel Goobar and Joel Johansson and Avinash Singh and Alice Townsend and Erin E. Hayes and Maggie L. Li and Steve Schulze and Suhail Dhawan and Jakob Nordin and Aleksandra Bochenek and Chiara Ventura and Conor M. B. Omand and Jacob L. Wise and Jesper Sollerman},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.18912},
eprint = {2609.18912},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.18912},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Follow-up of SN 2025wny VI: The Rate and Detectable Population of Strongly Lensed SLSNe-I in ZTF
AU - Jacob O. Hjortlund
AU - Edvard Mörtsell
AU - Ariel Goobar
AU - Joel Johansson
AU - Avinash Singh
AU - Alice Townsend
AU - Erin E. Hayes
AU - Maggie L. Li
AU - Steve Schulze
AU - Suhail Dhawan
AU - Jakob Nordin
AU - Aleksandra Bochenek
AU - Chiara Ventura
AU - Conor M. B. Omand
AU - Jacob L. Wise
AU - Jesper Sollerman
PY - 2026
DA - 2026/09/16
PB - arXiv
DO - 10.48550/arxiv.2609.18912
UR - https://arxiv.org/abs/2609.18912
AB - The Type I superluminous supernova (SLSN-I) SN 2025wny, multiply imaged by two foreground galaxies at z_l = 0.375, is the first confirmed strongly lensed SLSN and the highest-redshift (z_s = 2.015) multiply imaged supernova in a galaxy-scale configuration. We ask whether one discovery in seven years of Zwicky Transient Facility (ZTF) operations is consistent with expectations, and whether SN 2025wny is typical of the detectable population. We develop a forward simulation of strongly lensed SLSNe-I in ZTF, combining an empirically calibrated volumetric rate and luminosity function with a galaxy-scale deflector population, unresolved lensed light curves, and the actual ZTF observing history. We predict 0.037^+0.022_−0.020 yr^−1, consistent with the rate of 0.14^+0.31_−0.11 yr^−1 inferred from a single discovery in seven years of ZTF operations. Conditioning the simulation on discovery by ZTF corrects the magnifications and intrinsic luminosity of SN 2025wny for Malmquist- and magnification biases: the debiased peak bolometric luminosity, log_10(L_bol,int/erg s^−1) = 44.60^+0.05_−0.10, places it at the ∼97th percentile of the assumed SLSNe-I luminosity function. SN 2025wny is typical of the detectable population in redshift, luminosity, and magnification, but its 4.9'' image separation exceeds single-galaxy deflector expectations, implying our rates are conservative for wide-separation systems.
ER -