Terapix Star Formation Region IC 1396, © 2002 CFHT
Galaxy clustering analyses in the COSMOS Field
by HJMCC - Updated June 14th, 2005

Comparison of w(theta) measurements made on the various fields at 10hrs

There are four fields which were analysed here:

-  The Megacam-COSMOS i* data (2.8 deg^2) This are the Megacam images covering the COSMOS survey field, and corresponds exactly to the photometric catalogue being used for the spectroscopy at IAB<22.5.

-  The Suprime-cam COSMOS data (1.6 deg^2) This is the catalogue reduced by Peter and Herve. Note that I used Subaru aperture magnitudes, which at bright magnitudes will are not reliable. Note also that I used the masks produced by Yannick for the COSMOS/Megacam dataset, i.e., not Peter's masks.

-  The CFHTLS-d2 Megacam field (0.69 deg^2) This is one single contiguous MEGACAM pointing reduced at TERAPIX. It does not contain any of the PI data used to produce the Cosmos/MEGACAM stack. It was also reduced by different set of astrometric and photometric software than the MEGACAM survey data.

-  The VIRMOS-VVDS F10-hour field (4.0 deg^2) This is the VVDS survey field at 10hrs. This dataset was reduced by Sebastien Foucaud as part of his PhD thesis. Unfortunately, the CFH12K data used in this reduction was not corrected for scattered light.

All the magnitudes here (with the exception of the Subaru one) were corrected for galactic extinction variations on a point-by-point basis. The total areas I'm quoting here are after the masks

The first graph shows w(theta) as a function of limiting magnitude measured at 1^scales for four different surveys. The fits were always carried out with a fixed slope of 0.8 and over the same angular range, which is always 15''< theta <4'.

I-band scaling relation - 27.1 kb
I-band scaling relation
Correlation function amplitude at 1' as a function of IAB magnitude

Here is also the galaxy counts computed from these differen surveys, computed using the same masks. The total area of each survey is indicated.

IAB galaxy number counts - 28.7 kb
IAB galaxy number counts
Normalised galaxy counts for the four surveys

Now here are the amplitudes for each of the slices.

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