Does $H\to \gamma \gamma$ Taste like vanilla New Physics?

Abstract

We analyse the interplay between the Higgs to diphoton rate and electroweak precision measurements contraints in extensions of the Standard Model with new uncolored charged fermions that do not mix with the ordinary ones. We also compute the pair production cross sections for the lightest fermion and compare them with current bounds.

Comments: 19 pgs, 10 figures, typos fixed, reference added, small improvements made