Determining the Hubble constant using Giant extragalactic HII regions and HII galaxies
Abstract
We report the first results of a long term program aiming to provide accurate independent estimates of the Hubble constant (H0) using the L-sigma distance estimator for Giant extragalactic HII regions (GEHR) and HII galaxies. We have used VLT and Subaru high dispersion spectroscopic observations of a local sample of HII galaxies, identified in the SDSS DR7 catalogue in order to re-define and improve the L(Hbeta)-sigma distance indicator and to determine the Hubble constant. To this end we utilized as local calibration or `anchor' of this correlation, GEHR in nearby galaxies which have accurate distance measurements determined via primary indicators. Using our best sample of 69 nearby HII galaxies and 23 GEHR in 9 galaxies we obtain H0=74.3 +- 3.1 (statistical) +- 2.9 (systematic) km /s Mpc, in excellent agreement with, and independently confirming, the most recent SNe Ia based results.
Keywords
Cite
@article{arxiv.1203.6222,
title = {Determining the Hubble constant using Giant extragalactic HII regions and HII galaxies},
author = {Ricardo Chavez and Elena Terlevich and Roberto Terlevich and Manolis Plionis and Fabio Bresolin and Spyros Basilakos and Jorge Melnick},
journal= {arXiv preprint arXiv:1203.6222},
year = {2015}
}
Comments
5 pages, 4 figures; Replaces 1203.6222 after referee's suggestions; Accepted by MNRAS Letters