J/ApJ/612/652 Dimensionless coordinate distances to supernovae (Daly+, 2004)
Direct determination of the kinematics of the universe and properties of the
dark energy as functions of redshift.
Daly R.A., Djorgovski S.G.
<Astrophys. J., 612, 652-659 (2004)>
=2004ApJ...612..652D 2004ApJ...612..652D
ADC_Keywords: Supernovae ; Redshifts ; Galaxies, radio
Keywords: cosmological parameters - cosmology: observations - cosmology: theory
- dark matter - equation of state
Abstract:
Understanding the nature of dark energy, which appears to drive the
expansion of the universe, is one of the central problems of physical
cosmology today. In an earlier paper (Daly & Djorgovski,
2003ApJ...597....9D 2003ApJ...597....9D) we proposed a novel method to determine the
expansion rate E(z) and the deceleration parameter q(z) in a largely
model-independent way, directly from the data on coordinate distances
y(z). Here we expand this methodology to include measurements of the
pressure of dark energy p(z), its normalized energy density fraction
f(z), and the equation-of-state parameter w(z). We then apply this
methodology to a new, combined data set of distances to supernovae and
radio galaxies.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 30 20 Radio Galaxy Dimensionless Coordinate Distances
table2.dat 38 186 SNe Ia Dimensionless Coordinate Distances
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Byte-by-byte Description of file: table1.dat table2.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Name Source name (of galaxy of supernova)
11- 16 F6.4 --- z Redshift
18- 23 F6.4 --- y The dimensionless coordinate distance (1)
25- 30 F6.4 --- e_y The 1σ error in y
32- 37 A6 --- Sample Sample rating ("Gold" or "Silver")
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Note (1): The dimensionless coordinate distance is obtained from the
luminosity distance: (H0/c)*dL/(1+z).
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History:
From electronic version of the journal
References:
Daly and Djorgovski, Paper I 2003ApJ...597....9D 2003ApJ...597....9D
(End) Greg Schwarz [AAS], Marianne Brouty [CDS] 23-Feb-2005