The radio spectral index of the Vela supernova remnant
Departamento de Astronomía, Universidad de Chile, Casilla 36-D, Santiago, Chile
2 Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, 53121 Bonn, Germany
Corresponding author: H. Alvarez, firstname.lastname@example.org
Accepted: 9 March 2001
We have calculated the integrated flux densities of the different components of the Vela SNR between 30 and 8400 MHz. The calculations were done using the original brightness temperature maps found in the literature, a uniform criterion to select the background temperature, and a unique method to compute the integrated flux density. We have succeeded in obtaining separately, and for the first time, the spectrum of Vela Y and Vela Z. The index of the flux density spectrum of Vela X, Vela Y and Vela Z are -0.39, -0.70 and -0.81, respectively. We also present a map of brightness temperature spectral index over the region, between 408 and 2417 MHz. This shows a circular structure in which the spectrum steepens from the centre (Vela X) towards the periphery (Vela Y and Vela Z). X-ray observations show also a circular structure. We compare our spectral indices with those previously published.
Key words: ISM: supernova remnants / ISM: Vela X / radio continuum: ISM
© ESO, 2001