Supernova remnant mass cumulated along the star formation history of the
  z=3.8 radiogalaxies 4C41.17 and TN J2007-1316
  In this paper, we show that the supernova remnant (SNR) masses cumulated from
core-collapse supernovae along the star formation history of two powerful z=3.8
radio galaxies 4C41.17 and TN J2007-1316 reach up to > 10^9 Msun, comparable
with supermassive black hole (SMBH) masses measured from the SDSS sample at
similar redshifts. The SNR mass is measured from the already exploded supernova
mass after subtraction of ejecta at the galaxy age where the mass of still
luminous stars fits at best the observed spectral energy distribution (SED),
continuously extended to the optical-Spitzer-Herschel-submm domains, with the
help of the galaxy evolution model P\'egase.3. For the recent and old stellar
populations, SNR masses vary on 10^(9 to 10) Msun and the SNR-to-star mass
ratio between 1 and 0.1 percent is comparable to the observed low-z
SMBH-to-star mass ratio. For the template radio galaxy 4C41.17, SNR and stellar
population masses estimated from large aperture (>4arcsec=30kpc) observations
are compatible, within one mass order, with the total mass of multiple optical
HST (~700pc) structures, associated with VLA radio emissions, both at 0.1
arcsec. Probing the SNR accretion by central black holes is a simple
explanation for SMBH growth, requiring physics on star formation, stellar and
galaxy dynamics with consequences on various processes (quenching, mergers,
negative feedback) and a key to the relation bulge-SMBH.
