TY  - JOUR
AU  - Civiletti, M.
AU  - Pallis, C.
AU  - Shafi, Q.
PY  - 2014
DA  - 2014//
TI  - Upper bound on the tensor-to-scalar ratio in GUT-scale supersymmetric hybrid inflation
T2  - Phys. Lett. B
JO  - Physics Letters B
SP  - 276
EP  - 282
VL  - 733
PB  - Elsevier Science Bv
AB  - We explore the upper bound on the tensor-to-scalar ratio r in supersymmetric (F-term) hybrid inflation models with the gauge symmetry breaking scale set equal to the value 2.86 . 10(16) GeV, as dictated by the unification of the MSSM gauge couplings. We employ a unique renormalizable superpotential and a quasi-canonical Kahler potential, and the scalar spectral index n(s) is required to lie within the two-sigma interval from the central value found by the Planck satellite. In a sizable region of the parameter space the potential along the inflationary trajectory is a monotonically increasing function of the inflaton, and for this case, r less than or similar to 2.9.10(-4), while the spectral index running, vertical bar dn(s)/d ln k vertical bar, can be as large as 0.01. Ignoring higher order terms which ensure the boundedness of the potential for large values of the inflaton, the upper bound on r is significantly larger, of order 0.01, for subplanckian values of the inflaton, and vertical bar dn(s)/dlnk vertical bar similar or equal to 0.006.
SN  - 0370-2693
UR  - http://arxiv.org/abs/1402.6254
UR  - https://doi.org/10.1016/j.physletb.2014.04.060
DO  - 10.1016/j.physletb.2014.04.060
LA  - English
N1  - WOS:000336430400048
ID  - Civiletti_etal2014
ER  -