  We revisit the status of hybrid inflation in the light of Planck and recent
BICEP2 results, taking care of possible transient violations of the slow-roll
conditions as the field passes from the large field to the vacuum dominated
phase. The usual regime where observable scales exit the Hubble radius in the
vacuum dominated phase predicts a blue scalar spectrum, which is ruled out. But
whereas assuming slow-roll one expects this regime to be generic, by solving
the exact dynamics we identify the parameter space for which the small field
phase is naturally avoided due to slow-roll violations at the end of the large
field phase. When the number of e-folds generated at small field is negligible,
the model predictions are degenerated with those of a quadratic potential.
There exists also a transitory case for which the small field phase is
sufficiently long to affect importantly the observable predictions.
Interestingly, in this case the spectral index and the tensor to scalar ratio
agree respectively with the best fit of Planck and BICEP2. This results in a
\Delta \chi^2 \simeq 5.0 in favor of hybrid inflation for Planck+BICEP2 (\Delta
\chi^2 \simeq 0.9 for Planck only). The last considered regime is when the
critical point at which inflation ends is located in the large field phase. It
is constrained to be lower than about ten times the reduced Planck mass. The
analysis has been conducted with the use of Markov-Chain-Monte-Carlo bayesian
method, in a reheating consistent way, and we present the posterior probability
distributions for all the model parameters.
