Sie befinden Sich nicht im Netzwerk der Universität Paderborn. Der Zugriff auf elektronische Ressourcen ist gegebenenfalls nur via VPN oder Shibboleth (DFN-AAI) möglich. mehr Informationen...
A New Method to Calibrate the Magnitudes of Type Ia Supernovae at Maximum Light
Ist Teil von
The Astrophysical journal, 2006-08, Vol.647 (1), p.501-512
Ort / Verlag
Chicago, IL: IOP Publishing
Erscheinungsjahr
2006
Quelle
EZB Electronic Journals Library
Beschreibungen/Notizen
We present a new empirical method for fitting multicolor light curves of Type Ia supernovae (SNe). Our method combines elements from two widely used techniques in the literature: the m sub(15) template fitting method (Phillips et al.) and the Multicolor Light-Curve Shape method (MLCS; Riess et al.). An advantage of our technique is the ease of adding new colors, templates, or parameters to the fitting procedure. We use a large sample of published light curves to calibrate the relations between the absolute magnitudes at maximum and the postmaximum decline rate m sub(15) in BVRI filters. If we perform a cut in reddening and compare an unreddened with a reddened sample, we find that the two samples produce relations that are marginally consistent with each other. We find that individual subsamples from a given survey or publication have significantly tighter relationships between light-curve shape and luminosity than the relationship derived from the sum of all the samples, pointing to uncorrected systematic errors in the photometry, mainly in BV filters. Using our method, we calculate luminosity distances and host galaxy reddening to 89 SNe in the Hubble flow and construct a low-z Hubble diagram. The dispersion of the SNe in the Hubble diagram is s = 0.20 mag, or an error of 69% in distance to a single SN. Our technique produces similar or smaller dispersion in the low-z Hubble diagram than other techniques in the literature.