On the integrated continuum radio spectrum of supernova remnant W44 (G34.7-0.4): new insights from Planck

TL;DR

This study analyzes the radio spectrum of supernova remnant W44 up to 70 GHz using Planck data, exploring emission models and suggesting possible spinning dust emission detection amidst spectral uncertainties.

Contribution

It provides new insights into the high-frequency radio emission of SNR W44, highlighting the potential presence of spinning dust emission and the spectral effects of synchrotron losses.

Findings

Possible detection of spinning dust emission.

Spectral features suggestive of synchrotron losses.

High scatter in data limits definitive conclusions.

Abstract

In this paper, the integrated continuum radio spectrum of supernova remnant (SNR) W44 was analyzed up to 70 GHz, testing the different emission models that can be responsible for its particular shape. The observations by the Planck space telescope made possible to analyze the high frequency part of radio emission from SNRs. Although the quality of radio continuum spectrum (a high scatter of data points at same frequencies) prevents us to make definite conclusions, the possibility of spinning dust emission detection towards this remnant is emphasized. In addition, a concave-down feature, due to synchrotron losses, can not be definitely dismissed by the present knowledge of the integrated radio continuum spectrum of this SNR.