Engineering topics

Schenewerk, M. S.

Publications and source records attributed to Schenewerk, M. S..

2 records

NASA NTRS1988

HCO emission from H II-molecular cloud interface regions

A survey of well-known molecular clouds in the four strongest HCO N(k-,k+) = 1(01)-O(60) hyperfine transitions has been carried out to determine the prevalence of HCO and to study its chemistry. HCO emission was observed in seven molecular clouds. Three of these, NGC 2264, W49, and NGC 7538, were not previously known sources of HCO. In addition, NGC 2024 and Sgr B2 were mapped and shown to have extensive HCO emission. The survey results show the HCO abundance to be enhanced in H II-molecular cloud interface regions and support a correlation between C(+) and HCO emission. The strength of the HCO emission in NGC 2024 is interpreted in terms of this enhancement and the source structure and proximity to Earth.

Schenewerk, M. S.↗

NASA NTRS1985

Observations of several new transitions of interstellar HCO

Four new transitions of the interstellar formyl radical, HCO have been detected. Five transitions are now known for interstellar HCO, and thus its identification is secure. The column density found by assuming NGC 2024 is an extended source is N subT(HCO) = (8.5 + or - 4.0) x 10 to the 12th/sq cm. This gives a fractional abundance (abundance relative to hydrogen) for NGC 2024 which agrees quite well with some theoretical predictions. Several unidentified lines were detected and are reported here. Tentative identification for some of the unidentified lines are suggested.

Snyder, L. E.↗