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.