Observational constraints on particle production during inflation
نویسندگان
چکیده
Resonant particle production, along with many other physical processes which change the effective equation of state (EOS) during inflation, introduces a feature in the primordial power spectrum which in many models has a step-like shape. We calculate observational constraints on resonant particle production, parametrized in the form of an effective step height, Neff and location in k-space, kbreak. Combining data from the cosmic microwave background and the 2dF Galaxy Redshift Survey yields strong constraints in some regions of parameter space, although the range in k-space which can be probed is restricted to k ∼ 0.001− 0.1h Mpc. We also discuss the implications of our findings for general models which change the effective EOS during inflation. PACS numbers: 14.60.Pq,95.35.+d,98.80.-k Observational constraints on particle production during inflation 2
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