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A Comparison of Local SNIa with the IRAS PSCz Gravity Field

D. J. Radburn-Smith·J. R. Lucey·M. J. Hudson
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Abstract

We compare the measured peculiar velocities of 98 local (<150/h Mpc) type Ia supernovae with predictions derived from the PSCz survey. There is excellent agreement between the two datasets with a best fit beta_I (=Omega_m^0.6/b_I) of 0.55+-0.06. Subsets of the supernovae dataset are further analysed and the above result is found to be robust with respect to culls by distance, host-galaxy extinction and to the choice of reference frame in which the analysis is carried out. Alternative methods of determining beta_I including density-density comparisons, dipole measurements and WMAP-based results are also discussed. We conclude that most recent determinations are consistent with a value of beta_I=0.5.

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D. J. Radburn-Smith, J. R. Lucey, M. J. Hudson. 2004-09-23. A Comparison of Local SNIa with the IRAS PSCz Gravity Field. https://doi.org/10.1111/j.1365-2966.2004.08420.x

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