SN 2024cld: unveiling the complex mass-loss histories of evolved supergiant progenitors to core collapse supernovae
Year: 2025
Type: article
Abstract: ABSTRACT Pre-explosion mass loss in supernova (SN) progenitors is a crucial unknown factor in stellar evolution, yet has been illuminated recently by the diverse zoo of interacting transients. We present SN 2024cld, a transitional core-collapse SN at a distance of 39 Mpc, straddling the boundary between SN II and SN IIn, showing persistent interaction with circumstellar material (CSM) similar to H-rich SN 1998S and PTF11iqb. The SN was discovered and classified just 12 h post-explosion via the GOTO-FAST high-cadence program. Optical spectroscopy, photometry, and polarimetry over 220 d chart the complex, long-lived interaction in this transient. Early evolution is dominated by CSM interaction, showing a 14 d rise to a peak absolute magnitude of $g=-17.6$ mag, with clear flash-ionisation signatures. SN 2024cld also shows a slowly-evolving late time light curve powered by CSM interaction, with high-velocity (6000 km s$^{-1}$) shoulders on a strong multi-component H$\alpha$ profile. Dense polarimetric coverage reveals marked evolution in the photospheric geometry–peaking at 2 per cent polarisation 10 days post-explosion, and rotating $\approx 60^\circ$ as the ejecta sweep more distant CSM. We observe a narrow ($\approx$60 km s$^{-1}$) H$\alpha$ P Cygni feature throughout, associated with pre-shock CSM. SN 2024cld represents among the best-observed 98S-like SNe to date, revealing a multi-component CSM structure: a dense, inner aspherical envelope, CSM disk/torus, and tenuous, extended wind. We propose this SN arose from an evolved supergiant progenitor experiencing multiple mass loss episodes in its terminal years, with binary interaction plausibly generating the CSM disk. SN 2024cld constrains the progenitors and mass-loss paradigms of 98S-like SNe, unveiling the chaotic ends of evolved supergiant stars from afar.
Authors: T L Killestein, M Pursiainen, R Kotak, P Charalampopoulos, J Lyman, K Ackley, S Belkin, D L Coppejans, B Davies, M J Dyer, L Galbany, B Godson, D Jarvis, N Koivisto, A Kumar, M Magee, M Mitchell, D O’Neill, A Sahu, B Warwick, R P Breton, T Butterley, Y-Z Cai, J Casares, V S Dhillon, N Elias-Rosa, M Fraser, D K Galloway, B Gompertz, M González-Bañuelos, C P Gutiérrez, T Kangas, E Kankare, L Kelsey, T Kravtsov, G Leloudas, S P Littlefair, K Matilainen, S Mattila, T Nagao, K Noysena, L K Nuttall, P O’Brien, D Pollacco, G Ramsay, A Reguitti, T M Reynolds, I Salmaso, R L C Starling, D Steeghs, M Stritzinger, K Ulaczyk, G Valerin, Z -Y Wang, R Wilson
Institutions: University of Turku, University of Warwick, Monash University, University of Sheffield, Institute of Space Sciences, Institut d'Estudis Espacials de Catalunya, Royal Holloway University of London, University of Birmingham, University of Manchester, Durham University, Chinese Academy of Sciences, Yunnan Observatories, Instituto de Astrofísica de Canarias, Osservatorio Astronomico di Padova, National Institute for Astrophysics, University College Dublin, University of Cambridge, DTU Space, Technical University of Denmark, European University Cyprus, Aalto University, National Astronomical Research Institute of Thailand, University of Portsmouth, University of Leicester, Armagh Observatory & Planetarium, Brera Astronomical Observatory, University of Copenhagen, Astronomical Observatory of Capodimonte, Aarhus University, Beijing Normal University, Beijing Normal University, Zhuhai
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $3,046
Funders: Villum Fonden, University of Portsmouth, UK Research and Innovation, National Astronomical Research Institute of Thailand, Leverhulme Trust, University of Leicester, University of Warwick, European Commission, National Research Foundation, Danmarks Grundforskningsfond, Monash University, National Natural Science Foundation of China, Academy of Finland, Generalitat de Catalunya, Isaac Newton Trust, Ministerio de Ciencia e Innovación, Turun Yliopisto, Instituto de Astrofísica de Canarias, Turun Yliopistosäätiö, Science and Technology Facilities Council, Agència de Gestió d'Ajuts Universitaris i de Recerca, Agencia Estatal de Investigación, National Key Research and Development Program of China
Awards: The Gravitational wave Optical Transient Observer, Tidal disruption of stars in galactic nuclei, G1175115578, A consolidated grant for Sheffield Astrophysics 2021-2024, Warwick Astronomy and Astrophysics Consolidated Grant 2020-2023, G1855990336, G1903188662, G1938211519, G2064873908, G2245903464, G2262748287, G2269359191, G2309174360, G2601397997, G2690211755, G2880135662, G288263039, G3002654571, G3005324705, G300979063, G3074516354, G3100516318, G3116764410, The Gravitational wave Optical Transient Observer - facility operations 2024-2027, G3439265645, G3480869486, G3498411469, G3518538256, G3534859928, G3577539154, G3578086565, G3619454252, G3681454997, G3754922453, G387506447, G3897114864, G3948860332, G3969857380, G4019291869, G4042783231, G4198364353, G425668148, Cosmic Dawn Center (DAWN), G430777504, G434337789, Studying Exotic and extReme EruptioNs AnD Explosions (SERENADE), G464105488, G4655338613, G4691210332, G4863782507, G4938054238, G5013843854, G5080475149, G5195188938, G5215710831, G5421974903, G5596821196, G5852091828, The Gravitational wave Optical Transient Observer, Warwick Astronomy & Astrophysics Consolidated Grant 2023-2026, G617610489, G6513613686, G7001747737, Ambiguous Progenitors of Powerful Hydrogen-rich Supernovae, G8511709958, G8904106095, G99296377
OpenAlex ID: W7117101446