Bibcode
DOI
Jones, B.; Worrall, D. M.; Rodriguez-Espinosa, J. M.; Stein, W. A.; Gillett, F. C.
Referencia bibliográfica
Astronomical Society of the Pacific, Publications (ISSN 0004-6280), vol. 96, Sept. 1984, p. 692-698. NSF-supported research.
Fecha de publicación:
9
1984
Número de citas
6
Número de citas referidas
6
Descripción
Observations carried out with a 8-13 micron grating-spectrometer of Mrk
231 and NGC 4151 are reported. The Mrk 231 data can be fitted to various
thermal dust emission models or a single power law, with dust
extinction. In all the model fits, except for that of graphite and
silicon carbide grain emission, a component of silicate absorption of
optical depth of not more than 0.7 is required. Confirming published
work, the absorption being at the redshift of the low-redshift
absorption-line system is ruled out. The high values of silicate optical
depth absorption do not give ratios to the galaxy's visual extinction
which are comparable to those of galactic H II regions. Weak evidence
for a 10-micron absorption feature in NGC 4151 is also reported. This is
somewhat contrary to expectation, since the visual extinction of NGC
4151 is lower than that of Mrk 231, and since there is evidence to
support a nonthermal rather than thermal dust origin for the infrared
continuum emission.