Northwestern Univ., Evanston, IL (United States). Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA) and Dept. of Physics and Astronomy; The Adler Planetarium, Chicago, IL (United States)
Trinity College, Dublin (Ireland). School of Physics
Univ. of California, Berkeley, CA (United States). Dept. of Physics and Dept. of Astronomy
Weizmann Inst. of Science, Rehovot (Israel). Dept. of Particle Physics and Astrophysics
California Institute of Technology (CalTech), Pasadena, CA (United States). Cahill Center for Astrophysics
Stockholm Univ. (Sweden). Dept of Astronomy
Liverpool John Moores Univ. (UK). Astrophysics Research Inst.
Heidelberg Inst. for Theoretical Studies, Heidelberg (Germany)
Stockholm Univ. (Sweden). Dept. of Physics
Nordita, KTH Royal Institute of Technology and Stockholm Univ., Stockholm (Sweden)
Univ. of Washington, Seattle, WA (United States). Dept. of Astronomy
California Institute of Technology (CalTech), Pasadena, CA (United States). CalTech Optical Observatories
Univ. of Washington, Seattle, WA (United States). Dept. of Astronomy and The eScience Inst.
Univ. de Lyon (France)
California Institute of Technology (CalTech), Pasadena, CA (United States). Infrared Processing and Analysis Center (IPAC)
California Institute of Technology (CalTech), Pasadena, CA (United States). Cahill Center for Astrophysics and Center for Data Driven Discovery
Univ. of California, Berkeley, CA (United States). Dept. of Physics and Dept. of Astronomy; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Computational Cosmology Center
Univ. Clermont Auvergne, Clermont-Ferrand (France). Lab. de Physique de Clermont
Weizmann Inst. of Science, Rehovot (Israel). Dept. of Particle Physics and Astrophysics; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Northwestern Univ., Evanston, IL (United States). Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA) and Dept. of Physics and Astronomy
California Institute of Technology (CalTech), Pasadena, CA (United States). Cahill Center for Astrophysics and CalTech Optical Observatories
Early observations of Type Ia supernovae (SNe Ia) provide essential clues for understanding the progenitor system that gave rise to the terminal thermonuclear explosion. Here, we present exquisite observations of SN 2019yvq, the second observed SN Ia, after iPTF 14atg, to display an early flash of emission in the ultraviolet (UV) and optical. Our analysis finds that SN 2019yvq was unusual, even when ignoring the initial flash, in that it was moderately underluminous for a SN Ia ($$M_g \approx -18.5$$ mag at peak) yet featured very high absorption velocities ($$v \approx 15,0000$$ km s-1 for Si II λ6355 at peak). We find that many of the observational features of SN 2019yvq, aside from the flash, can be explained if the explosive yield of radioactive 56Ni is relatively low (we measure $$M_{^{56}\mathrm{Ni}} = 0.31 \pm 0.05\,M_\odot$$) and it and other iron-group elements are concentrated in the innermost layers of the ejecta. To explain both the UV/optical flash and peak properties of SN 2019yvq we consider four different models: interaction between the SN ejecta and a nondegenerate companion, extended clumps of 56Ni in the outer ejecta, a double-detonation explosion, and the violent merger of two white dwarfs. Each of these models has shortcomings when compared to the observations; it is clear additional tuning is required to better match SN 2019yvq. In closing, we predict that the nebular spectra of SN 2019yvq will feature either H or He emission, if the ejecta collided with a companion, strong [Ca II] emission, if it was a double detonation, or narrow [O I] emission, if it was due to a violent merger.
Miller, A. A., et al. "The Spectacular Ultraviolet Flash from the Peculiar Type Ia Supernova 2019yvq." The Astrophysical Journal (Online), vol. 898, no. 1, Jul. 2020. https://doi.org/10.3847/1538-4357/ab9e05
Miller, A. A., Magee, M. R., Polin, A., Maguire, K., Zimmerman, E., Yao, Y., Sollerman, J., Schulze, S., Perley, D. A., Kromer, M., Dhawan, S., Bulla, M., Andreoni, I., Bellm, E. C., De, K., Dekany, R., Delacroix, A., Fremling, C., ... Kulkarni, S. R. (2020). The Spectacular Ultraviolet Flash from the Peculiar Type Ia Supernova 2019yvq. The Astrophysical Journal (Online), 898(1). https://doi.org/10.3847/1538-4357/ab9e05
Miller, A. A., Magee, M. R., Polin, A., et al., "The Spectacular Ultraviolet Flash from the Peculiar Type Ia Supernova 2019yvq," The Astrophysical Journal (Online) 898, no. 1 (2020), https://doi.org/10.3847/1538-4357/ab9e05
@article{osti_1638210,
author = {Miller, A. A. and Magee, M. R. and Polin, A. and Maguire, K. and Zimmerman, E. and Yao, Y. and Sollerman, J. and Schulze, S. and Perley, D. A. and Kromer, M. and others},
title = {The Spectacular Ultraviolet Flash from the Peculiar Type Ia Supernova 2019yvq},
annote = {Early observations of Type Ia supernovae (SNe Ia) provide essential clues for understanding the progenitor system that gave rise to the terminal thermonuclear explosion. Here, we present exquisite observations of SN 2019yvq, the second observed SN Ia, after iPTF 14atg, to display an early flash of emission in the ultraviolet (UV) and optical. Our analysis finds that SN 2019yvq was unusual, even when ignoring the initial flash, in that it was moderately underluminous for a SN Ia ($M_g \approx -18.5$ mag at peak) yet featured very high absorption velocities ($v \approx 15,0000$ km s-1 for Si II λ6355 at peak). We find that many of the observational features of SN 2019yvq, aside from the flash, can be explained if the explosive yield of radioactive 56Ni is relatively low (we measure $M_{^{56}\mathrm{Ni}} = 0.31 \pm 0.05\,M_\odot$) and it and other iron-group elements are concentrated in the innermost layers of the ejecta. To explain both the UV/optical flash and peak properties of SN 2019yvq we consider four different models: interaction between the SN ejecta and a nondegenerate companion, extended clumps of 56Ni in the outer ejecta, a double-detonation explosion, and the violent merger of two white dwarfs. Each of these models has shortcomings when compared to the observations; it is clear additional tuning is required to better match SN 2019yvq. In closing, we predict that the nebular spectra of SN 2019yvq will feature either H or He emission, if the ejecta collided with a companion, strong [Ca II] emission, if it was a double detonation, or narrow [O I] emission, if it was due to a violent merger.},
doi = {10.3847/1538-4357/ab9e05},
url = {https://www.osti.gov/biblio/1638210},
journal = {The Astrophysical Journal (Online)},
issn = {ISSN 1538-4357},
number = {1},
volume = {898},
place = {United States},
publisher = {Institute of Physics (IOP)},
year = {2020},
month = {07}}
Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Advanced Scientific Computing Research (ASCR); Heising-Simons Foundation; National Science Foundation (NSF); Gordon and Betty Moore Foundation; European Research Council (ERC)
Grant/Contract Number:
AC02-05CH11231
OSTI ID:
1638210
Alternate ID(s):
OSTI ID: 23025143
Journal Information:
The Astrophysical Journal (Online), Journal Name: The Astrophysical Journal (Online) Journal Issue: 1 Vol. 898; ISSN 1538-4357