TY - JOUR
T1 - Circumstellar Interaction Signatures in the Low-luminosity Type II SN 2021gmj
AU - Meza-Retamal, Nicolás
AU - Dong, Yize
AU - Bostroem, K. Azalee
AU - Valenti, Stefano
AU - Galbany, Lluís
AU - Pearson, Jeniveve
AU - Hosseinzadeh, Griffin
AU - Andrews, Jennifer E.
AU - Sand, David J.
AU - Jencson, Jacob E.
AU - Janzen, Daryl
AU - Lundquist, Michael J.
AU - Hoang, Emily T.
AU - Wyatt, Samuel
AU - Brown, Peter J.
AU - Howell, D. Andrew
AU - Newsome, Megan
AU - Padilla Gonzalez, Estefania
AU - Pellegrino, Craig
AU - Terreran, Giacomo
AU - Kouprianov, Vladimir
AU - Hiramatsu, Daichi
AU - Jha, Saurabh W.
AU - Smith, Nathan
AU - Haislip, Joshua
AU - Reichart, Daniel E.
AU - Shrestha, Manisha
AU - Rosales-Ortega, F. Fabián
AU - Brink, Thomas G.
AU - Filippenko, Alexei V.
AU - Zheng, Wei Kang
AU - Yang, Yi
N1 - Publisher Copyright:
© 2024. The Author(s). Published by the American Astronomical Society.
PY - 2024/8/1
Y1 - 2024/8/1
N2 - 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 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 an 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 − 0.4 + 0.6 Mpc. From the tail of the light curve we obtain a radioactive nickel mass of M 56 Ni = 0.014 ± 0.001 M ⊙. 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 ⊙ 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.
AB - 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 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 an 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 − 0.4 + 0.6 Mpc. From the tail of the light curve we obtain a radioactive nickel mass of M 56 Ni = 0.014 ± 0.001 M ⊙. 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 ⊙ 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.
UR - https://www.scopus.com/pages/publications/85201270951
UR - https://www.scopus.com/pages/publications/85201270951#tab=citedBy
U2 - 10.3847/1538-4357/ad4d55
DO - 10.3847/1538-4357/ad4d55
M3 - Article
AN - SCOPUS:85201270951
SN - 0004-637X
VL - 971
JO - Astrophysical Journal
JF - Astrophysical Journal
IS - 2
M1 - 141
ER -