  We present the HINOTORI (star formation History INvestigatiOn TO find
RejuvenatIon) project to reveal the nature of rejuvenation galaxies (RGs),
which are galaxies that restarted their star formation after being quiescent.
As the first step of HINOTORI, we construct the largest RG sample with 1071
sources. We select these RGs from 8857 MaNGA (Mapping Nearby Galaxies at APO)
survey galaxies by reconstructing their star formation histories with
Prospector spectral energy distribution fitting code. Both optical spectral
data and UV to IR photometric data are used for the fitting. Using mock data,
we confirm that our method can detect weak rejuvenation events that form only
about 0.1% of the total stellar mass with high completeness. The RGs account
for ~10% of the whole sample, and rejuvenation events contribute on average
only about 0.1% of the total stellar mass in those galaxies but 17% of the
cosmic-star formation rate density today. Our RGs have a similar mass
distribution to quiescent galaxies (QGs). However, the morphology of the RGs is
more disk-like than QGs, suggesting that rejuvenation may occur selectively in
disk-like QGs. Our results also suggest the possibility of multiple-time
rejuvenation events in a single galaxy. Further spatially resolved analyses of
integral field unit data and radio observations and comparisons to simulations
are needed to identify the mechanism and the role of rejuvenation in galaxy
evolution.
