Circumstellar interaction signatures in the low luminosity type II SN 2021gmj

2024/01/08 by Nicolas Meza-Retamal, Nicolas Meza Retamal, Meza-Retamal, Nicolas +69 · 1 voice · 4 citations
Physics and Astronomy · #astro-ph.HE

paper · pdf · doi:10.48550/arxiv.2401.04027

Abstract

We present comprehensive optical observations of SN~2021gmj, a Type II supernova (SN~II) discovered within a day of explosion by the Distance Less Than 40~Mpc (DLT40) survey. Follow-up observations show that SN~2021gmj is a low-luminosity SN~II (LL~SN~II), with a peak magnitude M_V = -15.45 and Fe~II velocity of ∼ 1800 km s^-1 at 50 days past explosion. Using the expanding photosphere method, we derive a distance of 17.8^+0.6_-0.4~Mpc. From the tail of the light curve we obtain a radioactive nickel mass of 0.014 ± 0.001 M_\odot. The presence of circumstellar material (CSM) is suggested by the early-time light curve, early spectra, and high-velocity Hα in absorption. Analytical shock-cooling models of the light curve cannot reproduce the fast rise, supporting the idea that the early-time emission is partially powered by the interaction of the SN ejecta and CSM. The inferred low CSM mass of 0.025 M_\odot in our hydrodynamic-modeling light curve analysis is also consistent with our spectroscopy. We observe a broad feature near 4600 Å, which may be high-ionization lines of C, N, or/and He~II. This feature is reproduced by radiation-hydrodynamic simulations of red supergiants with extended atmospheres. Several LL~SNe~II show similar spectral features, implying that high-density material around the progenitor may be common among them.

Cited by

• SN 2022acko and the Properties of its Red Supergiant Progenitor: Direct Detection, Light Curves, and Nebular Spectroscopy
• Enabling Early Transient Discovery in LSST via Difference Imaging with DECam
• Diversity in Hydrogen-rich Envelope Mass of Type II Supernovae. (III). The mass-loss and evolutionary pathways of the red supergiant progenitors
• Red Supergiant problem viewed from the nebular phase spectroscopy of type II supernovae

Discussions

• These two observations were made to study the same object: the supernova SN-2021gmj, which was spotted on 20 March 2021. It was a type II supernova, probably even a type IIP. 🔭 Here are two papers ab [bsky, 7 points, 0 comments]

Related

• Intermediate-luminosity Type IIP SN 2021gmj: a low-energy explosion with signatures of circumstellar material
• Evidence of weak circumstellar medium interaction in the Type II SN 2023axu
• SN 2021dbg: A Luminous Type IIP-IIL Supernova Exploding from a Massive Star with a Layered Shell
• SN 2022acko: a low-luminosity SNe IIP with signs of early circumstellar interaction
• The bright long-lived Type II SN 2021irp powered by aspherical circumstellar material interaction (I): Revealing the energy source with photometry and spectroscopy