we propose raster imaging of a large field around centaurus a at 90 and 12 microns to search for thermal dust emission from the optical emission line jet, and from the hi and optical shells around the parent galaxy. as the closest radio galaxy, centaurus a provides the opportunity to study the miriad physical phenomena occuring in such sources in the greatest detail. in particular, centaurus a is famous for a series of emission line filaments oriented along the axis of the radio jet. such aligned line and radio emission turns out to be a common phenomenon in powerful radio galaxies at high redshift, and insight into the origin and ionization mechanism for this aligned gas will provide significant insight into the gaseous, and perhaps stellar, evolution of giant elliptical galaxies. centaurus a is also one of the arch-typal optical shell. galaxies. recent hi 21cm imaging has revealed neutral gas associated with the shells in centaurus a. also seen is an intimate relationship between one of the filaments in the optical jet. and one of the hi shells (schminocich etal 1994). the detection and characterization of the dust emission associated with the optical emission line filaments, and the hi and optical shells, should answer the question of the origin for the gas in these regions. also, determination of the dust color temperature in the line filaments should answer questions on the ionization mechanism of the line filaments, and constrain the interstellar radiation field (isrf) and dust-to-gas ratio in the hi shells. further, the proposed observations will image a big enough region to study the dust in the outer parts of the optical dust lane in centarus a, and to search for dust in regions away from both the line filaments and the hi shells.
Instrument
PHT32
Temporal Coverage
1996-07-23T08:11:42Z/1997-11-01T17:35:21Z
Version
1.0
Mission Description
The Infrared Space Observatory (ISO) was the worlds first true orbiting infrared observatory. Equipped with four highly-sophisticated and versatile scientific instruments, it was launched by Ariane in November 1995 and provided astronomers world-wide with a facility of unprecedented sensitivity and capabilities for a detailed exploration of the Universe at infrared wavelengths.
European Space Agency, CARILLI et al., 1999, 'INFRARED IMAGING OF THE OPTICAL EMISSION LINE JET AND OPTICAL AND HI SHELLS IN CENTAURUS A.', 1.0, European Space Agency, https://doi.org/10.5270/esa-688nky3
