Wild behaviour near the finish line: The Type Ibn SN 2020able and its stratified environment
Year: 2026
Type: article
Abstract: We present spectrophotometric observations of the Type Ibn supernova SN 2020able, along with a comprehensive analysis and modelling of its evolution. The transient occurred in SDSS J092602.93+243115.1, a faint host galaxy characterised by significantly subsolar metallicity (12 + log(O/H) ≃ 8.28 dex). The early photometric evolution and high peak luminosity ( L peak ≃ 4.4 × 10 43 erg s −1 ) indicate an efficient conversion of ejecta kinetic energy into radiation via interaction with the circumstellar medium. Light-curve modelling suggests that this interaction involves ejecta with a mass of M ej ≃ 1.3 M ☉ impacting a shell of M CSM ≃ 0.6 M ☉ . However, interaction is found to be geometrically and temporally confined within a few days after explosion, with the later evolution of the transient being dominated by the free expansion of the ejecta. Spectroscopic analysis reveals a complex, stratified, circumstellar environment. In addition to the innermost shocked region, we identify two additional He-rich shells: a dense inner one ( n e ≃ 1.4 × 10 9 cm −3 ) located at R ≳ 9.3 × 10 14 cm, and a more extended outer component reaching R out ≃ 3.3 × 10 15 cm and expanding at approximately 1.2 × 10 3 km s −1 . The physical parameters of the former suggest it was produced by a discrete, pre-supernova eruptive event similar to that of SN 2006jc, which expelled approximately 1.8 × 10 −2 M ☉ of material. Conversely, the expansion velocity of the outermost shell is consistent with the escape velocity of Wolf–Rayet stars, pointing towards a late WN- to WC-type progenitor as the most viable candidate for SN 2020able.
Source: Astronomy and Astrophysics
Authors: L. Tartaglia, E. Cappellaro, G. Valerin, A. Pastorello, S. Benetti, A. Reguitti, L. Tomasella, P. Lundqvist, K. Misra, A. Gangopadhyay, R. Dastidar, B. Ailawadhi, Dimple, B. Kumar, V. K. Jha, M. Singh, N. Elias-Rosa, C. P. Gutiérrez, D. A. Howell, D. Hiramatsu, C. Pellegrino, J. Andrews, D. J. Sand, N. Smith, J. Pearson, S. Wyatt, P. Ochner, Y.-Z. Cai, J. Burke, C. McCully, M. Newsome, E. Padilla Gonzalez
Institutions: Collurania Teramo Observatory, National Institute for Astrophysics, Osservatorio Astronomico di Padova, Brera Astronomical Observatory, Stockholm University, Aryabhatta Research Institute of Observational Sciences, Physical Research Laboratory, University of Birmingham, Yunnan University, Tata Institute of Fundamental Research, National Centre for Radio Astrophysics, Indian Institute of Astrophysics, Institute of Space Sciences, Las Cumbres Observatory Global Telescope Network, University of Florida, Goddard Space Flight Center, NSF NOIRLab, International Gemini Observatory, University of Arizona, University of Padua, Chinese Academy of Sciences, Yunnan Observatories, The University of Texas at Austin, Johns Hopkins University
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,865
Funders: National Science Foundation, Smithsonian Institution, U.S. Department of Energy, National Aeronautics and Space Administration, Alfred P. Sloan Foundation, California Institute of Technology, Northwestern University, Drexel University, University of Warwick, National Natural Science Foundation of China, Liverpool John Moores University, Ministerio de Ciencia e Innovación, Stockholms Universitet, Office of Science, Science and Technology Facilities Council, Agencia Estatal de Investigación, National Key Research and Development Program of China
Awards: G1401168639, G1530525900, G1855990336, Collaborative Research: Studying Nearby Cosmic Explosions from their Earliest Moments, G2262748287, G2309174360, Collaborative Research: The Multimessenger Treasure TROVE, a Tool for Rapid Object Vetting and Examination, Collaborative Research: WoU-MMA: Searches After Gravitational-waves Using Arizona's Observatories (SAGUARO), G2660406951, Exploring & Exploiting the Dynamic Optical Sky, G2835226076, G2998051782, G3002654571, G300979063, G306243560, G3100516318, G3439265645, G3480869486, ZWICKY TRANSIENT FACILITY, G3498411469, G3518538256, G3577539154, G3578086565, CDS&E: WoU-MMA: The Treasure Map, G387506447, G3969857380, G425668148, G430777504, G464105488, G4655338613, Speeding up the messenger: immediate detection of multimessenger transients with Las Cumbres Observatory, G5080475149, G5421974903, G5596821196, Unveiling the Local Population of Compact Binary Mergers, G617610489, G7084143925, G745419941, G8575141037, G8904106095, G944666937
OpenAlex ID: W7202199466