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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
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 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:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 40 260 Distances of 192 supernovae, 30 radio galaxies, and 38 galaxy clusters
See also: J/ApJ/612/652 : Dimensionless coordinate distances to supernovae (Daly+, 2004) Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
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
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).
History: From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 15-Sep-2010
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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