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DOE OSTI · 1656811

Pseudosmooth tribrid inflation in SU(5)

Masoud, Muhammad Atif·Rehman, Mansoor Ur·Shafi, Qaisar
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Abstract

A realistic tribrid model of sneutrino inflation is constructed in an R-symmetric SU(5) grand unified theory (GUT). To avoid the monopole problem, a pseudosmooth inflationary trajectory is generated with the help of an additional Z 5 symmetry which is broken during and after inflation. The predictions of inflationary parameters are made at the central value of the scalar spectral index, n s =0.968. The largest possible value of the tensor to scalar ratio, r ≲ 0.0027, is obtained with sub-Planckian field values (≲m P ). A successful realization of reheating and leptogenesis is achieved by avoiding the gravitino problem with a reheat temperature as low as 10 6 GeV. The predicted range of the gauge symmetry breaking scale, 5 × 10 16 ≲ M/GeV ≲ 5 × 10 17 , turns out to be somewhat larger than the typical GUT scale. Finally, with additional vector-like families, a successful gauge coupling unification is achieved by avoiding the no-go theorem related to R-symmetric SU(5) GUT.

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Masoud, Muhammad Atif, Rehman, Mansoor Ur, Shafi, Qaisar. 2020-04-23. Pseudosmooth tribrid inflation in SU(5). https://doi.org/10.1088/1475-7516%2F2020%2F04%2F041

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