%0 Journal Article
%T Do current data prefer a nonminimally coupled inflaton?
%A Boubekeur, L.
%A Giusarma, E.
%A Mena, O.
%A Ramirez, H.
%J Physical Review D
%D 2015
%V 91
%N 10
%I Amer Physical Soc
%@ 1550-7998
%G English
%F Boubekeur_etal2015
%O WOS:000354979300001
%O exported from refbase (https://references.ific.uv.es/refbase/show.php?record=2237), last updated on Thu, 11 Jun 2015 20:26:39 +0000
%X We examine the impact of a nonminimal coupling of the inflaton to the Ricci scalar, 1/2 xi R phi(2), on the inflationary predictions. Such a nonminimal coupling is expected to be present in the inflaton Lagrangian on fairly general grounds. As a case study, we focus on the simplest inflationary model governed by the potential V proportional to phi(2), using the latest combined 2015 analysis of Planck and the BICEP2/Keck Array. We find that the presence of a coupling xi is favored at a significance of 99% C.L., assuming that nature has chosen the potential V proportional to phi(2) to generate the primordial perturbations and a number of e-foldings N = 60. Within the context of the same scenario, we find that the value of xi is different from zero at the 2 sigma level. When considering the cross-correlation polarization spectra from the BICEP2/Keck Array and Planck, a value of r = 0.038(-0.030)(+0.039) is predicted in this particular nonminimally coupled scenario. Future cosmological observations may therefore test these values of r and verify or falsify the nonminimally coupled model explored here.
%R 10.1103/PhysRevD.91.103004
%U http://arxiv.org/abs/1502.05193
%U https://doi.org/10.1103/PhysRevD.91.103004
%P 103004-6pp