* Astronomy

Title: Exploring the supernova remnant G308.4-1.4
Authors: Tobias Prinz, Werner Becker

Aims: We present a detailed X-ray and radio wavelength study of G308.4-1.4, a candidate supernova remnant (SNR) in the ROSAT All Sky Survey and the MOST supernova remnant catalogue.
Methods: The SNR candidate and its central point sources were studied using observations from the Chandra X-ray Observatory, SWIFT, the Australian Telescope Compact Array (ATCA) at 1.4 and 2.5 GHz and WISE infrared observation at 24 \mu m.
Results: We conclude that G308.4-1.4 is indeed a supernova remnant by means of its morphology matching at X-ray, radio and infrared wavelength, its spectral energy distribution in the X-ray band and its emission characteristics in the radio band. G308.4-1.4 is a shell-type SNR. X-ray, radio and infrared emission is seen only in the eastern part of the remnant due to a strong spatial density variation of the interstellar medium around the remnant. The X-ray emission can best be described by an absorbed non-equilibrium collisional plasma with a hydrogen density of n_{H}=(1.02 ± 0.04) cm^{-2}, a plasma temperature of 6.3^{+1.2}_{-0.7} million Kelvin and an under-abundance of Iron, Neon and Magnesium, as well as an overabundance in Sulphur with respect to the solar values. A Sedov analysis revealed that the remnant is at a distance of ~ 10 kpc and the progenitor star exploded ~ 5000 to 7500 years ago. Two faint X-ray point sources located near to the remnant's geometrical center are detected. Both sources have no counterpart at other wavelengths, leaving them as candidates for the compact remnant of the supernova explosion.

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