SDSS-3 BOSS meeting, day 2

Today was quasar target-selection day, and the meeting (which lasted three hours) was great. The target-selection group downselected to one method from three or four competitors (all of which were performing well) for the core (uniformly selected) subsample and made decisions for operations through to the summer. But the group also tasked itself with quite a bit of research and optimization leading up to the summer so that corrections can be made for the second year of data. It was a challenging, tiring, and substantially successful session.

In the afternoon, Blanton spoke about tiling, drilling, and survey strategy. There are dangers, given weather and observing constraints, that the survey might end with a non-contiguous footprint in the North Galactic Cap. This would be bad for both the galaxy clustering and the Lyman-alpha forest clustering. So the challenge is to operate the survey—that is, make local day-to-day decisions—such that at the end of five years, there is a large and contiguous footprint observed. This is pretty hard, especially since contiguity at the end of five years is not, in any sense, a local constraint on operations.