Bias Properties of Extragalactic Distance Indicators. V.Ho From Luminosity Functions of Different Spiral Types and Luminosity Classes Corrected for Bias

Abstract

view Abstract Citations (26) References (98) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Bias Properties of Extragalactic Distance Indicators. V. H0 From Luminosity Functions of Different Spiral Types and Luminosity Classes Corrected for Bias Sandage, Allan Abstract The method originally used by Lemaitre (1927, 1931), Robertson (1928), Hubble (1929b), and Hubble & Humason (1931) to determine the Hubble constant at H0 ~ 500 km s^-1^ Mpc^-1^ is used again here with modern data. The refinements introduced by van den Bergh (1960a,b) and de Vaucouleurs (1979a,b) of binning the galaxies separately by Hubble type and luminosity class to narrow the dispersions of the individual luminosity functions, are adopted. The mean absolute magnitudes, <M(m,T,L)>, of galaxies of types Sb, Sbc, and Sc in the flux-limited RSA2 catalog varies systematically with luminosity class (L), as van den Bergh had originally demonstrated in his discovery papers. Arguments are given why the absolute magnitudes calculated from redshifts, used here, are more reliable than photometric distances derived in other ways. The local velocity field (v < 4000 km s^-1^) is remarkably quiet when corrected to the Virgocentric frame. Corrections to change the flux-limited luminosity functions to bias-free mean absolute magnitudes for distance-limited samples, <M(o,T,L)>+5 log(H0/50), are set out in tables. An absolute calibration of the relative luminosities is made using 11 local galaxies of known distance, giving H0 = 56+/-5 km s^-1^ Mpc^-1^. If an analysis had been made that ignored the correction for observational selection bias, an incorrect Hubble constant of 72+/-5 would have been obtained. To make H0 ~ 85 as advocated by many proponents of the short distance scale, would require that our present mean absolute magnitude zero point would have to differ from that of the short scale by 0.91 mag, which is a ~5 σ(M) error, showing that the short distance scale is impossible if the distances to the calibrators adopted here are correct. Publication: The Astronomical Journal Pub Date: January 1996 DOI: 10.1086/117755 Bibcode: 1996AJ....111....1S Keywords: DISTANCE SCALES; GALAXIES: PHOTOMETRY; GALAXIES: DISTANCES AND REDSHIFTS full text sources ADS | data products SIMBAD (14) NED (11) Related Materials (10) Part 1: 1994ApJ...430....1S Part 2: 1994ApJ...430...13S Part 3: 1994ApJ...430...29F Part 4: 1995ApJ...452....1S Part 6: 1996AJ....111...18S Part 7: 1999AJ....117..157S Part 8: 1999ApJ...527..479S Part 9: 2000PASP..112..504S Part 10: 2002AJ....123.1179S Part 11: 2002AJ....123.2047S