Lower limits on the Hubble constant from models of type Ia supernovae

¹ Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Str. 1, 85741 Garching bei München, Germany e-mail: stritzin@mpa-garching.mpg.de
² European Southern Observatory, Karl-Schwarzschild-Str. 2, 85748 Garching bei München, Germany e-mail: bleibundgut@eso.org

Received: 9 July 2004
Accepted: 23 October 2004

Abstract

By coupling observations of type Ia supernovae with results obtained from the best available numerical models we constrain the Hubble constant, independently of any external calibrators. We find an absolute lower limit of H₀ > 50 . In addition, we construct a Hubble diagram with UVOIR light curves of 12 type Ia supernovae located in the Hubble flow, and when adopting the most likely values (obtained from 1-D and 3-D deflagration simulations) of the amount of  produced in a typical event, we find values of H₀ ≥ 66 ± 8 and ≥78 ± 9 , respectively. Our result may be difficult to reconcile with recent discussions in the literature as it seems that an Einstein-de Sitter universe requires H₀  46  in order to fit the temperature power spectrum of the cosmic microwave background and maintain the age constraints of the oldest stars.