Year: 2022
Type: article
Abstract: ABSTRACT Early-time radiative signals from Type Ia supernovae (SNe Ia) can provide important constraints on the explosion mechanism and the progenitor system. We present observations and analysis of SN 2019np, a nearby SN Ia discovered within 1–2 days after the explosion. Follow-up observations were conducted in optical, ultraviolet, and near-infrared bands, covering the phases from ∼−16.7 d to ∼+ 367.8 d relative to its B-band peak luminosity. The photometric and spectral evolutions of SN 2019np resemble the average behaviour of normal SNe Ia. The absolute B-band peak magnitude and the post-peak decline rate are Mmax(B) = −19.52 ± 0.47 mag and Δm15(B) = 1.04 ± 0.04 mag, respectively. No Hydrogen line has been detected in the nebular-phase spectra of SN 2019np. Assuming that the 56Ni powering the light curve is centrally located, we find that the bolometric light curve of SN 2019np shows a flux excess up to 5.0 per cent in the early phase compared to the radiative diffusion model. Such an extra radiation perhaps suggests the presence of an additional energy source beyond the radioactive decay of central nickel. Comparing the observed colour evolution with that predicted by different models, such as interactions of SN ejecta with circumstellar matter (CSM)/companion star, a double-detonation explosion from a sub-Chandrasekhar mass white dwarf (WD) and surface 56Ni mixing, we propose that the nickel mixing is more favoured for SN 2019np.
Authors: Hanna Sai, Xiaofeng Wang, Nancy Elias-Rosa, Yi Yang(杨轶), Jujia Zhang, Weili Lin, Jun Mo, Anthony L Piro, Xiangyun Zeng, Reguitti Andrea, Peter Brown, Christopher R Burns, Yongzhi Cai, Achille Fiore, Eric Y Hsiao, Jordi Isern, K Itagaki, Wenxiong Li, Zhitong Li, Priscila J Pessi, M M Phillips, Stefan Schuldt, Melissa Shahbandeh, Maximilian D Stritzinger, Lina Tomasella, Christian Vogl, Bo Wang, Lingzhi Wang, Chengyuan Wu, Sheng Yang, Jicheng Zhang, Tianmeng Zhang, Xinghan Zhang
Institutions: Tsinghua University, Beijing Planetarium, Beijing Academy of Science and Technology, Institute of Space Sciences, Osservatorio Astronomico di Padova, University of California, Berkeley, Chinese Academy of Sciences, Beijing Normal University, Yunnan Observatories, Carnegie Observatories, China Three Gorges University, Universidad Andrés Bello, Millennium Institute of Astrophysics, Texas A&M University, Florida State University, Institut d'Estudis Espacials de Catalunya, National Astronomical Observatory of Japan, Tel Aviv University, National Astronomical Observatories, University of Chinese Academy of Sciences, Universidad Nacional de La Plata, Las Campanas Observatory, Max Planck Institute for Astrophysics, Technical University of Munich, Aarhus University, Stockholm University, AlbaNova
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: bronze
Funders: National Aeronautics and Space Administration, Villum Fonden, University of Hawai'i, Centres de Recerca de Catalunya, Tencent, National Natural Science Foundation of China, Chinese Academy of Sciences, Generalitat de Catalunya, China Postdoctoral Science Foundation, Federación Española de Enfermedades Raras, Ministerio de Economía y Competitividad, Vetenskapsrådet, Youth Innovation Promotion Association of the Chinese Academy of Sciences, Danmarks Frie Forskningsfond, Recruitment Program of Global Experts, Agencia Nacional de Investigación y Desarrollo, INAF-Osservatorio Astronomico di Padova, National Key Research and Development Program of China, Youth Innovation Promotion Association, National Astronomical Observatories, Chinese Academy of Sciences, National Ten Thousand Talent Program, Center for Advanced Study, University of Illinois at Urbana-Champaign
Awards: G1331251360, G1739352493, G1832648013, G2473458285, G2635449810, G2640493488, G2668373727, G2800128827, G3170059513, G3238772472, G4216802067, G4219714792, G4314687588, 基于极大视场多波段巡天的时域天文学前沿研究, G4710959804, G4741463335, G4806004360, G4952568767, G5530518058, G5633776668, G594909916, G632749637, G6363312916, G6719336058, GREAT: Gravitational Radiation and Electromagnetic Astrophysical Transients, G7773936698, G7870691232, G837175144, G8832797873, Ia超新星多样性观测及其起源研究, G993116129
OpenAlex ID: W4281660682