A multiline study of a high-mass young stellar object in the Small
  Magellanic Cloud with ALMA: The detection of methanol gas at 0.2 solar
  metallicity
  We report the results of subparsec-scale submillimeter observations towards
an embedded high-mass young stellar object in the Small Magellanic Cloud (SMC)
with ALMA. Complementary infrared data obtained with the AKARI satellite and
the Gemini South telescope are also presented. The target infrared point source
is spatially resolved into two dense molecular cloud cores; one is associated
with a high-mass young stellar object (YSO core), while another is not
associated with an infrared source (East core). The two cores are dynamically
associated but show different chemical characteristics. Emission lines of CS,
C33S, H2CS, SO, SO2, CH3OH, H13CO+, H13CN, SiO, and dust continuum are detected
from the observed region. Tentative detection of HDS is also reported. The
first detection of CH3OH in the SMC has a strong impact on our understanding of
the formation of complex organic molecules in metal-poor environments. The gas
temperature is estimated to be ~10 K based on the rotation analysis of CH3OH
lines. The fractional abundance of CH3OH gas in the East core is estimated to
be (0.5-1.5) x 10^(-8), which is comparable with or marginally higher than
those of similar cold sources in our Galaxy despite a factor of five lower
metallicity in the SMC. This work provides observational evidence that an
organic molecule like CH3OH, which is largely formed on grain surfaces, can be
produced even in a significantly lower metallicity environment compared to the
solar neighborhood. A possible origin of cold CH3OH gas in the observed dense
core is discussed.
