3 research outputs found
Deep CO Observations and the CO-to-H_2 Conversion Factor in DDO 154, a Low Metallicity Dwarf Irregular Galaxy
We present a deep spectroscopic search for CO emission in the dwarf irregular
galaxy DDO154, which has an Oxygen abundance of only 1/20 the solar value. The
observations were conducted in order to constrain the CO-to-
conversion factor at low metallicity. No CO was detected, however, despite
being one of the sensitive observations done towards galaxies of this type. We
succeed in putting a strong lower limit on the conversion factor, at least 10
times the Galactic value. Our result supports previous studies which argue for
a high conversion factor at low metallicity.Comment: 11 pages, 4 figures. Accepted for publication in PAS
Near-infrared spectroscopy of Cepheids in the Galactic nuclear disk
We are carrying out near-infrared spectroscopy of Cepheids in the Galactic nuclear disk. The H-band spectra taken with SUBARU/IRCS indicate that their kinematics are consistent with the rotation of the nuclear disk