Imaging the supernova remnant G346.6-0.2 at radio wavelengths

CASTELLETTI G., GIACANI E.

San Juan

Congreso; Primera Reunión Anual Binacional entre la Asociación Argentina de Astronomía y la Asociación Chilena de Astronomía; 2011

G346.6−0.2 is a small (80 in size) supernova remnant (SNR) located in the Galactic plane for which the detection of five OH (1720 MHz) masers along its southern edge suggests the mutual SN shock-molecular cloud interaction. Based on existing X-ray observations made with Suzaku satellite it was proposed to be the oldest ejecta dominated shell-like SNR known today (1 × 10^4 yr). We present new radio observations of G346.6−0.2 made with the Giant Metrewave Radio Telescope (GMRT) in the continuum at 327 MHz. Even at this low frequency, these observations significantly improve the sensitivity and angular resolution of all previously published radio images of this remnant. Using the new dataset combined with archival observations taken from the Molonglo Observatory Synthesis Telescope (MOST) catalog at 843 MHz and from the Very Large Array (VLA) at 1465 MHz, we study variations in the radio spectral index in both position and frequency, looking for spectral signatures originated in the interaction with dense surroundinggas. Furthermore, we investigate the correlation between the radio and the X-ray emission from this SNR.