Tyler Pritchard (NYU) convenes a meeting on Mondays at NYU to discuss time-domain astrophysics. Today we had a discussion of a very simple idea: Use the rates of short GRBs that are observed and measured (using physical models from the MacFadyen group at NYU) to have certain jet–observer offset angles to infer rates for all the way-off-axis events that won't be GRB triggers but might be seen in LSST or other ground-based optical or radio surveys. Seems easy, right? It turns out it isn't trivial at all, because the extrapolation of a few well-understood events in gamma-rays, subject to gamma-ray selection effects to a full population of optical and radio sources (and then assessing those selection effects) requires quite a few additional or auxiliary assumptions. This is even more true for the bursts where we don't know redshifts. I was surprised to hear myself use the astronomy word "V-max"! But we still (as a group) feel like there must be low-hanging fruit. And this is a great application for the MacFadyen-group models, which predict brightness as a function of wavelength, time, and jet–observer angle.
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