Title: The Twins Embedding of Type Ia Supernovae. I. The Diversity of Spectra at Maximum Light

Abstract

In this work, we study the spectral diversity of Type Ia supernovae (SNe Ia) at maximum light using high signal-to-noise spectrophotometry of 173 SNe Ia from the Nearby Supernova Factory. We decompose the diversity of these spectra into different extrinsic and intrinsic components, and we construct a nonlinear parameterization of the intrinsic diversity of SNe Ia that preserves pairings of "twin"SNe Ia. We call this parameterization the "Twins Embedding."Our methodology naturally handles highly nonlinear variability in spectra, such as changes in the photosphere expansion velocity, and uses the full spectrum rather than being limited to specific spectral line strengths, ratios, or velocities. We find that the time evolution of SNe Ia near maximum light is remarkably similar, with 84.6% of the variance in common to all SNe Ia. After correcting for brightness and color, the intrinsic variability of SNe Ia is mostly restricted to specific spectral lines, and we find intrinsic dispersions as low as ~0.02 mag between 6600 and 7200 Å. With a nonlinear three-dimensional model plus one dimension for color, we can explain 89.2% of the intrinsic diversity in our sample of SNe Ia, which includes several different kinds of "peculiar"SNe Ia. A linear model requires seven dimensionsmore » to explain a comparable fraction of the intrinsic diversity. We show how a wide range of previously established indicators of diversity in SNe Ia can be recovered from the Twins Embedding. In a companion article, we discuss how these results can be applied to the standardization of SNe Ia for cosmology.« less

Authors:

Boone, K. ;

• Search DOE PAGES for author "Boone, K."
• Search DOE PAGES for ORCID "0000-0002-5828-6211"

Aldering, G.; Antilogus, P. ;

• Search DOE PAGES for author "Antilogus, P."
• Search DOE PAGES for ORCID "0000-0002-0389-5706"

Aragon, C. ;

• Search DOE PAGES for author "Aragon, C."
• Search DOE PAGES for ORCID "0000-0002-9502-0965"

Bailey, S.; Baltay, C. ;

• Search DOE PAGES for author "Baltay, C."
• Search DOE PAGES for ORCID "0000-0003-0424-8719"

Bongard, S.; Buton, C. ;

• Search DOE PAGES for author "Buton, C."
• Search DOE PAGES for ORCID "0000-0002-3780-7516"

Copin, Y. ;

• Search DOE PAGES for author "Copin, Y."
• Search DOE PAGES for ORCID "0000-0002-5317-7518"

Dixon, S. ;

• Search DOE PAGES for author "Dixon, S."
• Search DOE PAGES for ORCID "0000-0003-1861-0870"

Fouchez, D. ;

• Search DOE PAGES for author "Fouchez, D."
• Search DOE PAGES for ORCID "0000-0002-7496-3796"

Gangler, E. ;

• Search DOE PAGES for author "Gangler, E."
• Search DOE PAGES for ORCID "0000-0001-6728-1423"

Gupta, R. ;

• Search DOE PAGES for author "Gupta, R."
• Search DOE PAGES for ORCID "0000-0003-1820-4696"

Hayden, B. ;

• Search DOE PAGES for author "Hayden, B."
• Search DOE PAGES for ORCID "0000-0001-9200-8699"

Hillebrandt, W.; Kim, A. G. ;

• Search DOE PAGES for author "Kim, A. G."
• Search DOE PAGES for ORCID "0000-0001-6315-8743"

Kowalski, M. ;

• Search DOE PAGES for author "Kowalski, M."
• Search DOE PAGES for ORCID "0000-0001-8594-8666"

Küsters, D.; Léget, P. -F. ;

• Search DOE PAGES for author "Léget, P. -F."
• Search DOE PAGES for ORCID "0000-0002-8357-3984"

Mondon, F. more »; Nordin, J. ;

• Search DOE PAGES for author "Nordin, J."
• Search DOE PAGES for ORCID "0000-0001-8342-6274"

Pain, R. ;

• Search DOE PAGES for author "Pain, R."
• Search DOE PAGES for ORCID "0000-0003-4016-6067"

Pecontal, E.; Pereira, R.; Perlmutter, S. ;

• Search DOE PAGES for author "Perlmutter, S."
• Search DOE PAGES for ORCID "0000-0002-4436-4661"

Ponder, K. A. ;

• Search DOE PAGES for author "Ponder, K. A."
• Search DOE PAGES for ORCID "0000-0002-8207-3304"

Rabinowitz, D.; Rigault, M. ;

• Search DOE PAGES for author "Rigault, M."
• Search DOE PAGES for ORCID "0000-0002-8121-2560"

Rubin, D. ;

• Search DOE PAGES for author "Rubin, D."
• Search DOE PAGES for ORCID "0000-0001-5402-4647"

Runge, K.; Saunders, C. ;

• Search DOE PAGES for author "Saunders, C."
• Search DOE PAGES for ORCID "0000-0002-4094-2102"

Smadja, G. ;

• Search DOE PAGES for author "Smadja, G."
• Search DOE PAGES for ORCID "0000-0002-9093-8849"

Suzuki, N. ;

• Search DOE PAGES for author "Suzuki, N."
• Search DOE PAGES for ORCID "0000-0001-7266-930X"

Tao, C.; Taubenberger, S. ;

• Search DOE PAGES for author "Taubenberger, S."
• Search DOE PAGES for ORCID "0000-0002-4265-1958"

Thomas, R. C.; Vincenzi, M. « less

Publication Date:

Thu May 06 00:00:00 EDT 2021

Research Org.:

Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)

Sponsoring Org.:

USDOE Office of Science (SC), High Energy Physics (HEP); National Aeronautics and Space Administration (NASA); German Research Foundation (DFG); National Natural Science Foundation of China (NSFC); European Research Council (ERC)

Contributing Org.:

The Nearby Supernova Factory

OSTI Identifier:

1831106

Grant/Contract Number:  

AC02-05CH11231; 15-ADAP15- 0256; FKZ 50OR1503; FKZ 50OR1602; 11173017; 759194

Resource Type:

Accepted Manuscript

Journal Name:

The Astrophysical Journal

Additional Journal Information:

Journal Volume: 912; Journal Issue: 1; Journal ID: ISSN 0004-637X

Publisher:

IOP Publishing

Country of Publication:

United States

Language:

English

Subject:

79 ASTRONOMY AND ASTROPHYSICS; Type Ia supernovae; Standard candles; Observational cosmology