Spitzer, steady-state clustering

Morad and I "finished" the Spitzer proposals, although they will probably need to be resubmitted a few times as we (read: Blanton) find typos and improve the language and the specificity of the goals. My problem is: If you knew what you were going to do with the data, you wouldn't have to ask for it. I have trouble being specific in proposals.

Morad and I discussed his small-scale galaxy–galaxy clustering result in terms of a simple model: Imagine the clustering is "created" by a steady inflow of galaxies. Then the number density n(R) as a function of radius R should be related to the flow rate dR/dt. Two thoughts: (1) You can then reverse engineer the flow rate from the number density, or (2) You can use the intuition that the flow rate ought to increase with decreasing radius to argue that n(R) cannot be "steeper" (more centrally concentrated) than R–2. Morad is finding something steeper than this! One possibility: The flow rate into the system is not steady, but is in fact decreasing with time. This could steepen it, in principle. But it is certainly strange, especially at small scales where dynamical friction ought to dominate.

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