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arXiv · 2409.08888

Characterization of M51 supernova remnants with the imaging spectrometer SITELLE

Billy Gamache·Laurent Drissen·Carmelle Robert·Mykola Posternak
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Abstract

We present preliminary results of a detailed 3D study of supernova remnants in the nearby spiral M51 using data from the SIGNALS survey obtained with the imaging Fourier transform spectrometer SITELLE at the Canada-France-Hawaii telescope (CFHT). Data cubes covering the entire galaxy were gathered in three spectral ranges: SN3 (647-685 nm, R = 5000), SN2 (482-513 nm, R = 600) and SN1 (363-386 nm, R = 1000). The spectral resolution of the SN3 cube allows a precise, spatially resolved measurement of the velocity dispersion of each object. While most of the SNRs were known from previous surveys based on imagery and long-slit spectroscopy, we now provide 2D line flux and kinematic maps for all of them and found 20 new candidates. Most of the SNRs show velocity dispersions ($\sigma$) in the range 30-80 km/s, which is typical for middle-aged SNRs. Finally, we compare the properties of SNRs with those of thousands of HII regions included in the same dataset.

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Billy Gamache, Laurent Drissen, Carmelle Robert, Mykola Posternak. 2024-09-13. Characterization of M51 supernova remnants with the imaging spectrometer SITELLE. https://arxiv.org/abs/2409.08888

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