Friday, February 02, 2007

Wanted Distractions

Decided to put aside the cluster correlations and work on accessing a database through the web using Python. Over the break I put my Mom's recipes into a database web applicatioin using python. I looked into doing something like that with a larger data set, it is as straighforward as it sounds. The only trick will be convincing the sysadmin that it is secure enough.

There has been an exchange in the cluster group about how to model the lensing signal. It has become clear that mis-centering of cluster sample relative to the mass could be a real interpretational issue. Any mis-centering is basically degenerate with the halo concentration. Eduardo Rozo and Dave Johnston have ideas on how to constrain the mis-centering outside of the lensing signal to break the degeneracy.

I think this centering issue could severely limit the usefullness of the M/L measurements on halo scales. We can only account for the mis-centering with modeling, but we don't want to assume a form for the light distribution, certainly not NFW. One of the points is to see how different the profiles are in mass and light. On the other hand, if we can constain the mis-centering outside of these measurements the very high S/N light measurements could be recovered non-parametrically.

Erin

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