Pre-main sequence accretion in the low metallicity Galactic star-forming
  region Sh 2-284
  We present optical spectra of pre-main sequence (PMS) candidates around the
H$\alpha$ region taken with the Southern African Large Telescope, SALT, in the
low metallicity ($Z$) Galactic region Sh 2-284, which includes the open cluster
Dolidze 25 with an atypical low metallicity of $Z$ $\sim$ 1/5 $Z_{\odot}$. It
has been suggested on the basis of both theory and observations that PMS
mass-accretion rates, $\dot M_{\rm{acc}}$, are a function of $Z$. We present
the first sample of spectroscopic estimates of mass-accretion rates for PMS
stars in any low-$Z$ star-forming region. Our data-set was enlarged with
literature data of H$\alpha$ emission in intermediate-resolution R-band
spectroscopy. Our total sample includes 24 objects spanning a mass range
between 1 - 2 $M_{\odot}$ and with a median age of approximately 3.5 Myr. The
vast majority (21 out of 24) show evidence for a circumstellar disk on the
basis of 2MASS and Spitzer infrared photometry. We find $\dot M_{\rm{acc}}$ in
the 1 - 2 $M_{\odot}$ interval to depend quasi-quadratically on stellar mass,
with $\dot M_{\rm{acc}}$ $\propto$ $M_{\ast}^{2.4\,\pm\,0.35}$, and inversely
with stellar age $\dot M_{\rm{acc}}$ $\propto$ $t_{\ast}^{-\,0.7\,\pm\,0.4}$.
Furthermore, we compare our spectroscopic $\dot M_{\rm{acc}}$ measurements with
solar $Z$ Galactic PMS stars in the same mass range, but, surprisingly find no
evidence for a systematic change in $\dot M_{\rm{acc}}$ with $Z$. We show that
literature accretion-rate studies are influenced by detection limits, and we
suggest that $\dot M_{\rm{acc}}$ may be controlled by factors other than
$Z_{\ast}$, $M_{\ast}$, and age.
