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The Distances to Five Type~II Supernovae Using the Expanding Photosphere Method and the Value of $H_0$

Brian P. Schmidt Robert P. Kirshner·Ronald G. Eastman·Mark M. Phillips·Nicholas B. Suntzeff·Mario Hamuy·Jose Maza·Roberto Aviles
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Abstract

We have used observations gathered at CTIO to measure distances by the Expanding Photosphere Method (EPM) to 5 Type II supernovae. These supernovae lie at redshifts from cz = 1100 km/s to z = 5500 km/s, and increase to 18 the number of distances measured using EPM. We compare distances derived to 11 Type II supernovae with distances to their host galaxies measured using the Tully-Fisher method. We find that the Tully-Fisher distances average 11%+-7% smaller. The comparison shows no significant evidence of any large distance-dependent bias in the Tully-Fisher distances. We employ the sample of EPM distances from 4.5~Mpc to 180~Mpc to derive a value for the Hubble Constant. We find H_0 = 73 +- 6 (statistical) +- 7 (systematic}) km/s/Mpc.

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Brian P. Schmidt Robert P. Kirshner, Ronald G. Eastman, Mark M. Phillips, Nicholas B. Suntzeff, Mario Hamuy, Jose Maza, Roberto Aviles. 1994-07-29. The Distances to Five Type~II Supernovae Using the Expanding Photosphere Method and the Value of $H_0$. https://arxiv.org/abs/astro-ph/9407098

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