A spatially complete 13CO j = 1-0 survey of the Orion A cloud.
NAGAHAMA T., MIZUNO A., OGAWA H. and FUKUI Y.
Abstract (from CDS):
We present the results of new 13CO J = 1-0 observations of the Orion A molecular cloud made with two 4 m telescopes at Nagoya University. The area observed, corresponding to l ∼ 208°-215° and b ∼ -20°.5 to -18°.0, covers the full extent of this giant molecular cloud at a 2'.0 grid spacing with a 2'.7 beam. The present observations provide the first complete coverage of the cloud in 13CO with a reasonably high angular resolution relative to the cloud's size. In addition, the high velocity resolution of 0.1 km.s–1 allowed us to resolve velocity components of the 13CO emission. The molecular distribution is highly elongated along the Galactic plane and is filamentary, as is consistent with previous molecular maps. The total molecular mass of the cloud is estimated to be ∼5.4x104M☉. By using the velocity channel maps every 0.5 km.s–1, 39 individual filamentary components have been identified, and their basic physical quantities have been estimated. They typically are 4.8 pc in length, 1.4 pc in width, and 660 M☉ in mass. We also find that these filamentary components are nearly in virial equilibrium.