Engineering topics

Geis, Norbert

Publications and source records attributed to Geis, Norbert.

4 records

NASA NTRS1995

A multi-wavelength study of 30 Doradus: The Interstellar Medium in a low-metallicity galaxy

We report maps of the 158 micron (C II) line, the 63 micron and 146 micron (C I) lines, the 2.2 micron Br gamma line, and the 2.6 mm CO (1-0) line toward the 30 Doradus complex in the Large Magellanic Cloud. The maps of all tracers emphasize the shell-like structure of the 30 Doradus region which is seen edge-on. The fact that the molecular gas as traced by CO (1-0) and the photo dissociated gas as traced by (C II) are co-extensive over tens of parsecs can only be explained by a highly fragmented structure of the interstellar medium which allows UV radiation to penetrate deep into the molecular cloud. Clumpiness is also the key to understanding the extremely high (C II)/CO line intensity ratios.

Poglitsch, Albrecht↗

NASA NTRS1995

Extragalactic diffuse (C II) emission

The 158 micro m (CII) line has been mapped in the galaxies Centaurus A, M83, NGC 6946, and NGC 891. The emission exists over very large scales, peaking in the nuclei and extending beyond the spiral arms and molecular disks. While most of the (CII) emission from the nuclei and spiral arms originates in photodissociated gas, the diffuse atomic gas can account for much of the (CII) emission in the extended regions.

Madden, Suzanne C.↗

NASA NTRS1995

A search for hydrogen lasers in MWC 349 from the KAO

We report the first observations of H15 alpha (169.4114 microns) and H10 alpha (52.5349 microns) in MWC 349 from the KAO. We obtain a 3 sigma upper limit of 2 x 10(exp -19) W/sq cm for H15 alpha and a flux of 3.6 +/- 1.3 x 10(exp -19) W/sq for H10 alpha. These fluxes are consistent with an appreciable excess due to laser amplification down to quantum numbers n approx. equals 10.

Strelnitski, Vladimir S.↗

NASA NTRS1995

FIFI: The MPE Garching/UC Berkeley Far-Infrared Imaging Fabry-Perot Interferometer

We describe the performance characteristics of the MPE Garching/UC Berkeley Far-Infrared Imaging Fabry-Perot Interferometer (FIFI) for the Kuiper Airborne Observatory (KAO). The spectrometer features two or three cryogenic tunable Fabry-Perot filters in series giving spectral resolution R of up to 10(exp 5) in the range of 40 microns less than lambda less than 200 microns, and an imaging 5x5 array of photoconductive detectors with variable focal plane plate scale. The instrument works at background limited sensitivity of up to 2 x 10(exp -19) W cm(exp -2) Hz(exp -1/2) per pixel per resolution element at R = 10(exp 5) on the KAO.

Geis, Norbert↗