J/ApJ/677/1 Dimensionless coordinate distances (Daly+, 2008)
Improved constraints on the acceleration history of the universe and the
properties of the dark energy.
Daly R.A., Djorgovski S.G., Freeman K.A., Mory M.P., O'Dea C.P., Kharb P.,
Baum S.
<Astrophys. J., 677, 1-11 (2008)>
=2008ApJ...677....1D 2008ApJ...677....1D
ADC_Keywords: Supernovae ; Redshifts ; Galaxies, radio
Keywords: cosmological parameters - cosmology: observations
cosmology: theory - dark matter - equation of state
Abstract:
We extend and apply a model-independent analysis method developed
earlier by Daly & Djorgovski (2003ApJ...597....9D 2003ApJ...597....9D and 2004, Cat.
J/ApJ/612/652) to new supernova, radio galaxy, and galaxy cluster
samples to study the acceleration history of the universe and the
properties of the dark energy. There is good agreement between results
obtained with radio galaxies and supernovae, suggesting that both
distance indicators are reliable. The deceleration parameter q(z) is
obtained assuming only the validity of the FRW metric, allowing for a
range of values of space curvature, and independent of a gravity
theory and the physical nature of the contents of the universe. We
show that q0 is independent of space curvature, and obtain
q0=-0.48±0.11. The transition redshift when q0=0 is
zT=0.78+0.08-0.27 for zero space curvature, and has a weak
dependence on space curvature. We find good agreement between
model-independent quantities and those predicted by general
relativity, indicating that GR provides a good description of the data
over look-back times of ten billion years.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 40 260 Distances of 192 supernovae, 30 radio galaxies,
and 38 galaxy clusters
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See also:
J/ApJ/612/652 : Dimensionless coordinate distances to supernovae (Daly+, 2004)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 2 A2 --- OType Source type (1)
4- 20 A17 --- Name Source name (2)
22- 26 F5.3 --- z Redshift
28- 33 F6.4 --- y Dimensionless coordinate distance (3)
35- 40 F6.4 --- e_y The 1σ uncertainty in y
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Note (1): Type as follows:
SN = supernova;
RG = radio galaxy;
CL = cluster of galaxies.
Note (2): sn1977ff is very likely a misprint for sn1997ff and has been
corrected in the table.
Note (3): 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
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 15-Sep-2010