High resolution observations of the radio galaxy NGC5128 at 10.7 GHz

Journal Article · Mon Oct 01 04:00:00 EDT 1973 · Nature (London) Phys. Sci., v. 245, no. 145, pp. 83-85

DOI:https://doi.org/10.1038/physci245083a0· OSTI ID:4378839

Price, K M; Stull, M A

NGC 5128 (Centaurus A) is stated to be an important object for study since it should be possible to observe small scale structure that might not be resolved in more distant objects of the same class. It is at a distance of ~ 4 Mpc and is the nearest of the strong radio galaxies. There are three principal regions of radio emission associated with NGC 5128. The first, the outer radio lobes'', consists of two sources, one located to the north and the other to the south of the galaxy. The second is the inner radio lobes'', and consists of two components on opposite sides of the optical galaxy and separated by ~7 arc min. The third lies in the central regions of NGC 5l28 and contains a compact nonthermal source that coincides in position with the infrared bright spot believed to lie at the nucleus. New high-resolution observations of radio intensity and polarization are here reported for the inner lobes and compact central source, which it is believed provide a significant new insight into the physical mechanisms responsible for radio and x radiation from this and other radio galaxies. The source was observed in the summer of 1973, using the five- element radiotelescope of the Stanford University Radio Astronomy Institute. At the observing frequency of 10.7 GHz the angular resolution of the Stanford array is 17 arc sec. The experimental procedure is described in detail. Scans for the SW and NE inner radio lobes'' are shown, and can be resolved into more than one component. The polarization data for the SW lobe show a remarkable picture; some of the six components show very high polarization, whilst others show low or negligible polarization. Furthermore the position angle changes from one component to another in a way correlated with the change in prcentage of polarized flux. A very simple physical model is described to which the data can be fitted, and implications are discussed for other radio galaxies. Integrated fluxes were calculated. (UK)

• Research Organization: Stanford Univ., CA
• NSA Number: NSA-29-013623
• OSTI ID: 4378839
• Journal Information: Nature (London) Phys. Sci., v. 245, no. 145, pp. 83-85, Journal Name: Nature (London) Phys. Sci., v. 245, no. 145, pp. 83-85; ISSN NPSCA
• Country of Publication: United Kingdom
• Language: English

Related Subjects

*RADIO GALAXIES-- POLARIZATION
FLUX DENSITY
GHZ RANGE 01-100
INFRARED RADIATION
N56500* --Physics (Astrophysics & Cosmology)--Galaxies
RADIOWAVE RADIATION
SPATIAL DISTRIBUTION