Today's article was referenced to in the WISE TF paper I summarised yesterday. I wanted to find out how the peculiar velocities and density fields were reconstructed.
Title: Reconstructed density and velocity fields from the 2MASS Redshift Survey
Authors: Erdoğdu, Lahav et al.
Year: 2006, http://mnras.oxfordjournals.org/content/373/1/45.full
I have to admit I did not understand the mathematics of this article, and will read Peebles 1973 and Fisher 1995 to understand what are the spherical harmonics and Fourier-Bessel functions in detail. What they do in order to transform the the redshift space to the real space is decompose the redshift space distribution into radial and angular components. Peculiar velocities affect only the radial component, so it is easier to deconvolve them.
The relationship between mass and light distribution is usually assumed to be linear with some proportionality constant (there is an article by Vivienne arguing that this is not the case).
They provide density and velocity maps up to cz = 16 0000 km/s, which covers the CALIFA redshift range. I could ask them for the velocity data and obtain the peculiar velocities/infall corrected distances for the sample. I think it would be useful for me later, when working with the density fields and spin alignments. We would also have these distances and their errors for all the galaxies, not only the ones identified as belonging to structures.
Previously I used the Virgo-GA-Shapley infall corrected redshifts from NED (obtained using this model: http://iopscience.iop.org/0004-637X/529/2/786/fulltext/). It's a simpler model, taking only these three attractors into account.
Title: Reconstructed density and velocity fields from the 2MASS Redshift Survey
Authors: Erdoğdu, Lahav et al.
Year: 2006, http://mnras.oxfordjournals.org/content/373/1/45.full
I have to admit I did not understand the mathematics of this article, and will read Peebles 1973 and Fisher 1995 to understand what are the spherical harmonics and Fourier-Bessel functions in detail. What they do in order to transform the the redshift space to the real space is decompose the redshift space distribution into radial and angular components. Peculiar velocities affect only the radial component, so it is easier to deconvolve them.
The relationship between mass and light distribution is usually assumed to be linear with some proportionality constant (there is an article by Vivienne arguing that this is not the case).
They provide density and velocity maps up to cz = 16 0000 km/s, which covers the CALIFA redshift range. I could ask them for the velocity data and obtain the peculiar velocities/infall corrected distances for the sample. I think it would be useful for me later, when working with the density fields and spin alignments. We would also have these distances and their errors for all the galaxies, not only the ones identified as belonging to structures.
Previously I used the Virgo-GA-Shapley infall corrected redshifts from NED (obtained using this model: http://iopscience.iop.org/0004-637X/529/2/786/fulltext/). It's a simpler model, taking only these three attractors into account.
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