Improved empirical models for Type Ia SNe Virtual Observatory Resource

Authors
  1. Saunders C.
  2. Aldering G.
  3. Antilogus P.
  4. Bailey S.
  5. Baltay C.
  6. Barbary K.,Baugh D.
  7. Boone K.
  8. Bongard S.
  9. Buton C.
  10. Chen J.
  11. Chotard N.
  12. Copin Y.,Dixon S.
  13. Fagrelius P.
  14. Fakhouri H.K.
  15. Feindt U.
  16. Fouchez D.
  17. Gangler E.,Hayden B.
  18. Hillebrandt W.
  19. Kim A.G.
  20. Kowalski M.
  21. Kusters D.
  22. Leget P.-F.,Lombardo S.
  23. Nordin J.
  24. Pain R.
  25. Pecontal E.
  26. Pereira R.
  27. Perlmutter S.,Rabinowitz D.
  28. Rigault M.
  29. Rubin D.
  30. Runge K.
  31. Smadja G.
  32. Sofiatti C.,Suzuki N.
  33. Tao C.
  34. Taubenberger S.
  35. Thomas R.C.
  36. Vincenzi M.,(the Nearby Supernova Factory)
  37. Published by
    CDS
Abstract

SN Ia cosmology depends on the ability to fit and standardize observations of supernova magnitudes with an empirical model. We present here a series of new models of SN Ia spectral time series that capture a greater amount of supernova diversity than is possible with the models that are currently customary. These are entitled SuperNova Empirical MOdels (SNEMO; https://snfactory.lbl.gov/snemo). The models are constructed using spectrophotometric time series from 172 individual supernovae from the Nearby Supernova Factory, comprising more than 2000 spectra. Using the available observations, Gaussian processes are used to predict a full spectral time series for each supernova. A matrix is constructed from the spectral time series of all the supernovae, and Expectation Maximization Factor Analysis is used to calculate the principal components of the data. K-fold cross-validation then determines the selection of model parameters and accounts for color variation in the data. Based on this process, the final models are trained on supernovae that have been dereddened using the Fitzpatrick and Massa extinction relation. Three final models are presented here: SNEMO2, a two-component model for comparison with current Type Ia models; SNEMO7, a seven-component model chosen for standardizing supernova magnitudes, which results in a total dispersion of 0.100mag for a validation set of supernovae, of which 0.087mag is unexplained (a total dispersion of 0.113mag with an unexplained dispersion of 0.097mag is found for the total set of training and validation supernovae); and SNEMO15, a comprehensive 15-component model that maximizes the amount of spectral time-series behavior captured.

Keywords
  1. astronomical-models
  2. supernovae
  3. spectroscopy
Bibliographic source Bibcode
2018ApJ...869..167S
See also HTML
https://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/869/167
IVOA Identifier IVOID
ivo://CDS.VizieR/J/ApJ/869/167
Document Object Identifer DOI
doi:10.26093/cds/vizier.18690167

Access

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http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/869/167
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History

2020-04-06T08:34:29Z
Resource record created
2020-04-06T08:34:29Z
Created
2020-05-28T08:37:23Z
Updated

Contact

Name
CDS support team
Postal Address
CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France
E-Mail
cds-question@unistra.fr