4.8. Distribution of C18O and HNCO emission in the Sagittarius B2 molecular cloud

Sgr B2, located at a distance of ∼100 pc from the Galactic center, is one of the most active, recent massive-star formation regions in the Galaxy. Based on the 13CO (J = 1–0) line data taken with the Nobeyama 45 m telescope, we presented a cloud collision scenario as the triggering mechanism of the burst of massive-star formation there (Hasegawa et al. 1994). In order to obtain further evidence supporting our model, we observed the Sgr B2 molecular cloud in various molecular lines with the 45 m telescope in 1992 February. Twelve points each with 20″ spacings were observed along several strips 3.67′ long at constant galactic longitudes through the major HII region complexes. Here we report the results of the two lines in the 110 GHz band, C18O (J = 1–0) and HNCO (50,5–40,4). Full description of the observations will be given elsewhere (Sato et al. 1997).

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4.6. Structure of the molecular cloud and star-forming activity in the Sagittarius B2 region

Symposium - International Astronomical Union ◽

10.1017/s0074180900084527 ◽

1998 ◽

Vol 184 ◽

pp. 177-178 ◽

Cited By ~ 1

Author(s):

Fumio Sato ◽

Tetsuo Hasegawa ◽

John B. Whiteoak ◽

Ryosuke Miyawaki

Keyword(s):

Star Formation ◽

Molecular Cloud ◽

Large Scale ◽

Massive Star ◽

Galactic Center ◽

Full Description ◽

Grid Spacing ◽

Restricted Area ◽

Star Forming ◽

Right Ascension

Sgr B2 is one of the most active star-forming complexes in our Galaxy located ~100 pc from the Galactic center. Whiteoak et al. (1987) found that groups of the OH and H2CO masers and the compact HII regions are aligned in a north-south line, and suggested that star formation there is being triggered by a single large-scale event such as an interaction between molecular clouds. In order to investigate the total molecular cloud distribution and the triggering mechanism of the active massive-star formation in the Sgr B2 region, we mapped it in the 13CO and C18O (J = 1–0) lines with the Nobeyama 45 m telescope in 1988 March and May. In the 13CO line, an area was mapped of 345″ in right ascension and 495″ in declination covering the whole Sgr B2 molecular cloud at a grid spacing of 15″. In the C18O line, more restricted area was observed at 7.5″ or 15″ spacing. The HPBW of the 45 m telescope was 16″ at 110 GHz. Full description of the observations will be given elsewhere (Whiteoak et al. 1997).

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Irradiated interfaces in the Ara OB1, Carina, Eagle Nebula, and Cyg OB2 massive star formation regions

High Energy Density Physics ◽

10.1016/j.hedp.2012.08.002 ◽

2012 ◽

Vol 8 (4) ◽

pp. 313-321 ◽

Cited By ~ 4

Author(s):

P. Hartigan ◽

J. Palmer ◽

L.I. Cleeves

Keyword(s):

Star Formation ◽

Massive Star ◽

Massive Star Formation ◽

Eagle Nebula ◽

Star Formation Regions

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FIR/NIR spectroscopy of the Galactic Center Arc region: The importance of massive star formation for ionization

Lecture Notes in Physics - The Physics and Chemistry of Interstellar Molecular Clouds ◽

10.1007/bfb0102174 ◽

2007 ◽

pp. 322-323

Author(s):

T. Krenz ◽

T. R. Geballe ◽

R. Genzel ◽

A. I. Harris ◽

A. Krabbe ◽

...

Keyword(s):

Star Formation ◽

Massive Star ◽

Galactic Center ◽

Nir Spectroscopy ◽

Massive Star Formation

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Massive Star Formation in W49

Symposium - International Astronomical Union ◽

10.1017/s0074180900095152 ◽

1987 ◽

Vol 115 ◽

pp. 143-145

Author(s):

J. Dreher ◽

S. Vogel ◽

S. Terebey ◽

W. J. Welch

Keyword(s):

Star Formation ◽

High Resolution ◽

Massive Star ◽

Hii Regions ◽

Molecular Line ◽

The Galaxy ◽

Molecular Lines ◽

H Ii Region ◽

Scale Structures ◽

The Continuum

W49 is the most luminous H II region complex in the galaxy. VLA maps in the continuum reveal a complex of more than two dozen compact HII regions, including a ring-like distribution of a dozen such regions within a volume of 1 pc. In addition to the VLA maps, we have obtained high resolution maps in this field with the Hat Creek Millimeter Interferometer in the following molecular lines: HCO+(1-0), H13CO+(1-0), SiO(v = 0, J = 2-1), SiO(v = 1, J = 2-1), H13CN(1-0), HC15N(1-0), SO2 [8(3,5)-9(2,8)], SO2[8(1,7)-8(0,8)], SO[2(2)-1(1)], and CH3CH2CN[10(1,10)-9(1,9)], all near 3 mm wavelengh. These maps will be discussed. The HCO+distribution corresponds to the larger scale structures observed in the continuum maps. In contrast the SO and SiO sources are quite compact. Using the detailed molecular line results obtained in the ORION/KL region as a guide, we are able to identify these latter sources as regions in which the star formation is at an earlier stage, regions where there are outflows.

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