INVESTIGADORES
CASTELLETTI Gabriela Marta
congresos y reuniones científicas
Título:
The low radio frequency properties of the SNR Kes 79
Autor/es:
CASTELLETTI G.; GIACANI E.; PARON S.; DUBNER G.
Lugar:
Isla Margarita
Reunión:
Simposio; XII Latin American Regional International Astronomical Union Meeting; 2007
Institución organizadora:
International Astronomical Union
Resumen:
Observations of the supernova remnants (SNRs) at meter and longer
wavelengths are powerful tools to differentiate physical processes
taking place either in the SNRs (e.g. shock acceleration) or in the
interstellar medium intervening along the line of sight towards them
(e.g. thermal absorption).Kes 79 (G33.6+0.1) is a Galactic SNR rich
in spatial structures in both, radio and X-ray bands, that make it ideal
for addressing questions of SNR physics. Its radio morphology at 1.5
GHz is dominated by a system of two concentric incomplete shells with
diameters about 8´ and 12´. Chandra observations of Kes 79 reveal many
filaments, multiple partial shells, a loop, and a protrusion. The X-ray
point source, CXOUJ 185238.6+004020, located close to the geometric
center of the remnant was proposed to be the compact stellar remnant
formed in the supernova envent, although no evidence for a surrounding
pulsar wind nebula was found in the X-rays. It has also been suggested
that Kes 79 is interacting with a molecular cloud that appears to be
partially surrounding its east and southeast borders.In this work we
present new high quality images of Kes 79 obtained at low radio
frequencies. The observations at 74 and 324 MHz were carried out using
multiple-configurations of the Very Large Array (VLA) of the NRAO. We
use these data and existing VLA observations at 1.5 GHz to perform an
accurate study of the spectral index behaviour over the remnant and its
relationship with the properties in the X-ray band of Kes 79. In
addition, using HI and CO data from public databases we investigate the
influence of the surrounding gas on the morphology of Kes 79.