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We study the mid-infrared (IR) and near-ultraviolet (UV) excess emissions ofspectroscopically selected quiescent galaxies on the optical red sequence. Weuse the Wide-field Infrared Survey Explorer ({\it WISE}) mid-IR and GalaxyEvolution Explorer ({\it GALEX}) near-UV data for a spectroscopic sample ofgalaxies in the Sloan Digital Sky Survey Data Release 7 to study the possibleconnection between quiescent red-sequence galaxies with and withoutmid-IR/near-UV excess. Among 648 12 $\mu$m detected quiescent red-sequencegalaxies without H$\alpha$ emission, 26% and 55% show near-UV and mid-IR excessemissions, respectively. When we consider only bright ($M_{r}$ $<$ $-$21.5)galaxies with early-type morphology, the fraction of galaxies with recent starformation is still 39%. The quiescent red-sequence galaxies with mid-IR andnear-UV excess emissions are optically fainter and have slightly smaller$D_{n}$4000 than those without mid-IR and near-UV excess emissions. We alsofind that mid-IR weighted mean stellar ages of quiescent red-sequence galaxieswith mid-IR excess are larger than those with near-UV excess, and smaller thanthose without mid-IR and near-UV excess. The environmental dependence of thefraction of quiescent red-sequence galaxies with mid-IR and near-UV excessseems strong even though the trends of quiescent red-sequence galaxies withnear-UV excess differ from those with mid-IR excess. These results indicatethat the recent star formation traced by near-UV ($\lesssim 1$ Gyr) and mid-IR($\lesssim 2$ Gyr) excess is not negligible among nearby, quiescent, red,early-type galaxies. We suggest a possible evolutionary scenario of quiescentred-sequence galaxies from quiescent red-sequence galaxies with near-UV excessto those with mid-IR excess to those without near-UV and mid-IR excess.

The Mid-Infrared and Near-Ultraviolet Excess Emissions of Quiescent Galaxies on the Red Sequence