Driving Conditions of Protostellar Outflows in Different Star-Forming
  Environments
  The evolution of collapsing clouds embedded in different star-forming
environments is investigated using three-dimensional non-ideal
magnetohydrodynamics simulations considering different cloud metallicities
($Z/\thinspace Z_\odot$ = 0, 10$^{-5}$, 10$^{-4}$, 10$^{-3}$, 10$^{-2}$,
10$^{-1}$ and 1) and ionisation strengths ($C_\zeta$=0, 0.01, 1 and 10, where
$C_\zeta$ is a coefficient controlling the ionisation intensity and $C_\zeta=1$
corresponds to the ionisation strength of nearby star-forming regions). With
all combinations of these considered values of $Z/\thinspace Z_\odot$ and
$C_\zeta$, 28 different star-forming environments are prepared and simulated.
The cloud evolution in each environment is calculated until the central density
reaches $n\approx10^{16}\,{\rm cm}^{-3}$ just before protostar formation, and
the outflow driving conditions are derived. An outflow appears when the (first)
adiabatic core forms in a magnetically active region where the magnetic field
is well coupled with the neutral gas. In cases where outflows are driven, their
momentum fluxes are always comparable to the observations of nearby
star-forming regions. Thus, these outflows should control the mass growth of
the protostars as in the local universe. Roughly, an outflow appears when
$Z/\thinspace Z_\odot>10^{-4}$ and $C_\zeta \ge 0.01$. It is expected that the
transition of the star formation mode from massive stars to normal solar-type
stars occurs when the cloud metallicity is enhanced to the range of
$Z/\thinspace Z_\odot\approx 10^{-4}$--$10^{-3}$, above which relatively
low-mass stars would preferentially appear as a result of strong mass ejection.
