1,511 research outputs found
Methanol detection in M82
We present a multilevel study of the emission of methanol, detected for the
first time in this galaxy, and discuss the origin of its emission. The high
observed methanol abundance of a few 10^-9 can only be explained if injection
of methanol from dust grains is taken into account. While the overall
[CH3OH]/[NH3] ratio is much larger than observed towards other starbursts, the
dense high excitation component shows a similar value to that found in NGC 253
and Maffei 2. Our observations suggest the molecular material in M 82 to be
formed by dense warm cores, shielded from the UV radiation and similar to the
molecular clouds in other starbursts, surrounded by a less dense
photodissociated halo. The dense warm cores are likely the location of recent
and future star formation within M 82.Comment: Accepted for publication in A&A Letter
A Molecular Counterpart to the Herbig-Haro 1-2 Flow
We present high angular resolution (12"-24") and high sensitivity 12CO and
13CO J=2-1 and J=1-0 observations of the HH 1-2 outflow. The observations show
the molecular counterpart, moving with a velocity of approx. 30 km/s, of the
optical bipolar system driven by the VLA 1 embedded source. Along the optical
jet there are certain regions where the molecular gas reaches deprojected
velocities of 100-200 km/s, and that we interpret as the molecular jet. The
bipolar CO outflow has a length of approx. 260" with a curved morphology
towards the North where it extends beyond the HH 1 object (approx. 120") .
Two new molecular outflows have been detected, one arising from IRAS
05339-0647 which excites the HH 147 optical flow and another powered by VLA 2
which drives the HH 144 optical outflow. The molecular outflow driven by the
VLA 3 source is also clearly detected and spatially resolved from the VLA 1
main outflow.Comment: 14 pages, 4 figures, accepted ApJLet
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