_version_ 1866914473161261056
author Dhanasingham, Birendra
Kelly, Patrick L.
Chen, Wenlei
Pierel, Justin
Oguri, Masamune
Perera, Derek
Diego, Jose M.
Zitrin, Adi
Meena, Ashish K.
Jauzac, Mathilde
Mahler, Guillaume
Mamuzic, Elias
Williams, Liliya L. R.
Taak, Yoon Chan
Koekemoer, Anton M.
Broadhurst, Thomas J.
Furtak, Lukas J.
Lagattuta, David
Williams, Hayley
Dalrymple, Kyle
Filippenko, Alexei V.
Gall, Christa
Gilman, Daniel
Hjorth, Jens
Jha, Saurabh W.
Larison, Conor
Lee, Chien-Hsiu
Mazzali, Paolo A.
Sharon, Keren
Suyu, Sherry H.
author_facet Dhanasingham, Birendra
Kelly, Patrick L.
Chen, Wenlei
Pierel, Justin
Oguri, Masamune
Perera, Derek
Diego, Jose M.
Zitrin, Adi
Meena, Ashish K.
Jauzac, Mathilde
Mahler, Guillaume
Mamuzic, Elias
Williams, Liliya L. R.
Taak, Yoon Chan
Koekemoer, Anton M.
Broadhurst, Thomas J.
Furtak, Lukas J.
Lagattuta, David
Williams, Hayley
Dalrymple, Kyle
Filippenko, Alexei V.
Gall, Christa
Gilman, Daniel
Hjorth, Jens
Jha, Saurabh W.
Larison, Conor
Lee, Chien-Hsiu
Mazzali, Paolo A.
Sharon, Keren
Suyu, Sherry H.
contents The multiply imaged SN 2022riv was discovered through a search of galaxy cluster fields as part of a Hubble Space Telescope (HST) SNAP program to find highly magnified stars. The supernova (SN) was detected in the last-to-arrive image of a galaxy at redshift $z=1.522$ strongly lensed by the foreground galaxy cluster RX J2129.7+0005. Follow up James Webb Space Telescope (JWST) NIRSpec G140M and PRISM spectroscopy yields a Type Ia SN classification. Using the SALT3-NIR light-curve fitter, we obtain a cosmology-independent measurement of the magnification of $5.35\pm1.01$ for the last-to-arrive image of the SN, with multiple SALT SN spectral time-series models yielding consistent constraints. The last-to-arrive image of SN 2022riv we detect appeared adjacent to the brightest cluster galaxy (BCG) at a location with an exceptionally high stellar mass density ($\sim 1-2$ dex higher than that of SN Refsdal), where microlensing is expected to introduce a 20-50% modulation of the magnification. Analyzing six independent lens models of the cluster, we find that four predict the magnification with much greater precision ($p < 0.05$) than would be expected by random chance, given the large effect anticipated from microlensing. Five models yield magnifications of roughly $4-7$ (within $1σ$) prior to accounting for microlensing, whereas HoliGRALE favors a significantly higher value of $15.39 \pm 0.85$. After incorporating nominal microlensing, the HoliGRALE prediction is within $1σ$ tension with our measurement. A companion paper (Dalrymple et al.) will present constraints on the relative time delay of the image that arrived earlier.
format Preprint
id arxiv_https___arxiv_org_abs_2604_11882
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle SN 2022riv in RX J2129: Discovery, Spectroscopic Classification, and Microlensing of a Strongly Lensed Type Ia Supernova from JWST and HST Observations
Dhanasingham, Birendra
Kelly, Patrick L.
Chen, Wenlei
Pierel, Justin
Oguri, Masamune
Perera, Derek
Diego, Jose M.
Zitrin, Adi
Meena, Ashish K.
Jauzac, Mathilde
Mahler, Guillaume
Mamuzic, Elias
Williams, Liliya L. R.
Taak, Yoon Chan
Koekemoer, Anton M.
Broadhurst, Thomas J.
Furtak, Lukas J.
Lagattuta, David
Williams, Hayley
Dalrymple, Kyle
Filippenko, Alexei V.
Gall, Christa
Gilman, Daniel
Hjorth, Jens
Jha, Saurabh W.
Larison, Conor
Lee, Chien-Hsiu
Mazzali, Paolo A.
Sharon, Keren
Suyu, Sherry H.
Cosmology and Nongalactic Astrophysics
Astrophysics of Galaxies
The multiply imaged SN 2022riv was discovered through a search of galaxy cluster fields as part of a Hubble Space Telescope (HST) SNAP program to find highly magnified stars. The supernova (SN) was detected in the last-to-arrive image of a galaxy at redshift $z=1.522$ strongly lensed by the foreground galaxy cluster RX J2129.7+0005. Follow up James Webb Space Telescope (JWST) NIRSpec G140M and PRISM spectroscopy yields a Type Ia SN classification. Using the SALT3-NIR light-curve fitter, we obtain a cosmology-independent measurement of the magnification of $5.35\pm1.01$ for the last-to-arrive image of the SN, with multiple SALT SN spectral time-series models yielding consistent constraints. The last-to-arrive image of SN 2022riv we detect appeared adjacent to the brightest cluster galaxy (BCG) at a location with an exceptionally high stellar mass density ($\sim 1-2$ dex higher than that of SN Refsdal), where microlensing is expected to introduce a 20-50% modulation of the magnification. Analyzing six independent lens models of the cluster, we find that four predict the magnification with much greater precision ($p < 0.05$) than would be expected by random chance, given the large effect anticipated from microlensing. Five models yield magnifications of roughly $4-7$ (within $1σ$) prior to accounting for microlensing, whereas HoliGRALE favors a significantly higher value of $15.39 \pm 0.85$. After incorporating nominal microlensing, the HoliGRALE prediction is within $1σ$ tension with our measurement. A companion paper (Dalrymple et al.) will present constraints on the relative time delay of the image that arrived earlier.
title SN 2022riv in RX J2129: Discovery, Spectroscopic Classification, and Microlensing of a Strongly Lensed Type Ia Supernova from JWST and HST Observations
topic Cosmology and Nongalactic Astrophysics
Astrophysics of Galaxies
url https://arxiv.org/abs/2604.11882