Year: 2026
Type: preprint
Abstract: SN 2025wny is a gravitationally lensed, hydrogen-poor superluminous supernova (SLSN-I) at z = 2.015. To date, it is the most extensively observed high-redshift core-collapse SN and has the most detailed rest-frame UV observations of any SLSN. We present densely sampled rest-frame UV-to-optical photometry and spectroscopy out to +80 d post-peak (rest frame) from several facilities, including JWST, Keck, VLT, Gemini, the Palomar 200-inch, the Fraunhofer Telescope at Wendelstein, and the Liverpool Telescope. Correcting for lensing magnification, SN 2025wny reaches a peak pseudo-bolometric luminosity of $L_{\rm peak}\gtrsim4\times10^{44}$ erg s$^{-1}$ over rest-frame 1500-4230 Å, placing it within the luminosity range of typical SLSNe-I. SN 2025wny exhibits several unusual features, including a continuum excess and sharp spectral features in the FUV from +20-60 d that coincide with an FUV light-curve plateau and higher inferred blackbody temperatures. SN 2025wny's spectra also show little to no UV line blanketing, no obvious O II absorption despite high temperatures, and evidence for C II, H$α$, and possible He I. Light-curve modeling suggests that SN 2025wny may require a hybrid or non-standard power source. This work provides some of the first detailed constraints on high-redshift SLSNe and establishes SN 2025wny as an essential spectral and photometric reference for identifying and interpreting high-redshift SLSNe discovered by Rubin and Roman.
Source: arXiv (Cornell University)
Authors: Li, Maggie L., Yan, Lin, Gkini, Anamaria, Townsend, Alice, Qin, Yu-Jing, Schulze, Steve, Sarin, Nikhil, Dhawan, Suhail, Johansson, Joel, Goobar, Ariel, Hjortlund, Jacob Osman, Mörtsell, Edvard, Sollerman, Jesper, Lunnan, Ragnhild, Perley, Daniel A., Nakhar, Ehud, Singh, Avinash, Gal-Yam, Avishay, Kasliwal, Mansi M., Omand, Conor M. B., Bochenek, Aleksandra, Busmann, Malte, Das, Kaustav K., Fremling, Christoffer, Gordon, Alexa C., Gruen, Daniel, Jacobson-Galán, Wynn, Hinds, K-Ryan, Liu, Chang, McGrath, Zoë, Marchesini, Ezequiel J., Martin, Christopher, Massey, Peter, Oei, Martijn S. S. L., Palazzi, Eliana, Prada, Francisco, Prusinski, Nikolaus Z., Rehemtulla, Nabeel, Rossi, Andrea, Rich, R. Michael, Rose, Sam, Santer, Killa, Shivaprasad, Surya, Turner, Hannah C., Ventura, Chiara, Wise, Jacob L., Coughlin, Michael, Sasli, Argyro, Sravan, Niharika
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7204800341