On the Origin of the Gamma-Ray Fields in the ARA Region

COMBI, J.A.; ROMERO, G. E.

ASTRONOMY AND ASTROPHYSICS

EDP SCIENCES S A

Lugar: Paris; Año: 1995 vol. 303 p. 872 - 880

0004-6361

We report and discuss results of 1435MHz observations of the continuum emission from the Ara region. Using data from the previous 408MHz all-sky survey by Haslam et al. (1981) we have computed the spectral index distribution in the region. After the subtraction of a background component, several interesting features can be observed at both frequencies. We pay particular attention to an extended nonthermal source which is coincident with a strong γ-ray emission zone at 10deg from the galactic plane. We suggest that this feature could be the result of the interaction of a supernova remnant (SNR) with an interstellar cloud. Our interpretation can explain both the nonthermal nature of the radio source as well as the enhancement in the γ-ray flux. Several parameters are estimated for this context and other possible interpretations are briefly discussed.