Published June 1989
| Version v1
Journal article
He I 10830-A observations of Seyfert 2 galaxies
- 1. California Univ., La Jolla (USA)
- 2. Aerospace Corp., Los Angeles, CA (USA)
Description
Measurements of the 10830-A transition of neutral helium are presented for 12 Seyfert 2 galaxies and the emission-line radio galaxy NGC 1275. The observed 10830-A to He I 5876-A ratios for these objects range from 4 to 24, showing that the objects are reddened. For a number of these galaxies, the observed H-alpha/H-beta values exceed that expected with uniform mixing of dust and gas. The results suggest that one or more mechanisms are destroying the 10830-A photons or are depopulating the 2 3S level. Three previously proposed mechanisms to explain this process are evaluated and it is found that all of the proposed mechanisms are lacking. 35 refs
Additional details
Publishing Information
- Journal Title
- Astrophysical Journal
- Journal Volume
- 341
- Series
- Astrophys. J.
- Journal Page Range
- 120-128
- ISSN
- 0004-637X
- CODEN
- ASJOA
INIS
- Country of Publication
- United States
- Country of Input or Organization
- United States
- INIS RN
- 21004527
- Subject category
- S79: ASTROPHYSICS, COSMOLOGY AND ASTRONOMY;
- Descriptors DEI
- BALMER LINES; COSMIC DUST; COSMIC GASES; GALAXY NUCLEI; HELIUM; INFRARED SPECTRA; MIXING; PHOTOIONIZATION; PHOTONS; RADIO GALAXIES; SEYFERT GALAXIES; SPECTROPHOTOMETRY
- Descriptors DEC
- BOSONS; COSMIC RADIO SOURCES; DUSTS; ELEMENTARY PARTICLES; ELEMENTS; FLUIDS; GALAXIES; GASES; IONIZATION; MASSLESS PARTICLES; NONMETALS; RARE GASES; SPECTRA