  I examine recent fittings of luminous supernovae (LSNe) with extra energy
sources of magnetar and helium burning and find that in about half of these
LSNe the fitting parameters have some problems. In some LSNe the total energy
of these two energy sources is larger than the kinetic energy of the ejecta
that the fitting yields. In some others LSNe the total energy of the delayed
neutrino explosion mechanism and these two extra sources combined is smaller
than the kinetic energy that the fitting yields. These difficulties suggest
that, like earlier claims that jets power superluminous supernovae (SLSNe),
jets also power the less luminous LSNe. A magnetar might also supply energy.
However, in most cases jets supply more energy than the magnetar, during the
explosion and possibly at late times. I strengthen an earlier claim that jets
launched at magnetar birth cannot be ignored. I explain the trend of maximum
rise time for a given luminosity of hydrogen deficient core collapse supernovae
(CCSNe), in particular LSNe and SLSNe, with a toy model of jets that are active
for a long time after explosion.
