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Observational constraints on particle production during inflation

Oystein Elgaroy·Steen Hannestad·Troels Haugboelle
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Abstract

Resonant particle production, along with many other physical processes which change the effective equation of state (EOS) during inflation, introduces a step-like feature in the primordial power spectrum. We calculate observational constraints on resonant particle production, parameterised in form of an effective step height, N_eff and location in k-space, k_break. 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 - 0.1 h Mpc^-1. We also discuss the implications of our findings for general models which change the effective EOS during inflation.

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Oystein Elgaroy, Steen Hannestad, Troels Haugboelle. 2003-10-10. Observational constraints on particle production during inflation. https://doi.org/10.1088/1475-7516%2F2003%2F09%2F008

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