Herschel far-infrared observations of the Carina Nebula complex II: The
  embedded young stellar and protostellar population
  The Carina Nebula represents one of the largest and most active star forming
regions known in our Galaxy with numerous very massive stars.Our recently
obtained Herschel PACS & SPIRE far-infrared maps cover the full area (about 8.7
deg^2) of the Carina Nebula complex and reveal the population of deeply
embedded young stellar objects, most of which are not yet visible in the mid-
or near-infrared.We study the properties of the 642 objects that are
independently detected as point-like sources in at least two of the five
Herschel bands.For those objects that can be identified with apparently single
Spitzer counterparts, we use radiative transfer models to derive information
about the basic stellar and circumstellar parameters.We find that about 75% of
the Herschel-detected YSOs are Class 0 protostars.The luminosities of the
Herschel-detected YSOs with SED fits are restricted to values of <=5400 Lsun,
their masses (estimated from the radiative transfer modeling) range from about
1 Msun to 10 Msun.Taking the observational limits into account and
extrapolating the observed number of Herschel-detected protostars over the IMF
suggest that the star formation rate of the CNC is about 0.017 Msun/yr.The
spatial distribution of the Herschel YSO candidates is highly inhomogeneous and
does not follow the distribution of cloud mass.Most Herschel YSO candidates are
found at the irradiated edges of clouds and pillars.This provides support to
the picture that the formation of this latest stellar generation is triggered
by the advancing ionization fronts.The currently ongoing star formation process
forms only low-mass and intermediate-mass stars, but no massive stars.The
far-infrared fluxes of the famous object EtaCar are about a factor of two lower
than expected from observations with the ISO obtained 15 years ago; this may be
due to dynamical changes in the circumstellar dust in the Homunculus Nebula.
