Distances to the supernova remnants in the inner disk

Abstract

<jats:p><jats:italic>Context.</jats:italic> Distance measurements of supernova remnants (SNRs) are essential as accurate estimates of physical size, dust masses, and some other properties of SNRs depend critically on accurate distance measurements. However, the determination of SNR distances is still a tough task.</jats:p> <jats:p><jats:italic>Aims.</jats:italic> Red clump stars (RCs) have a long history of being used as standard candles. In this work, we take RCs as tracers to determine the distances to a large group of SNRs in the inner disk.</jats:p> <jats:p><jats:italic>Methods.</jats:italic> We first selected RC stars based on the near-infrared (IR) color-magnitude diagram. Then the distance to and extinction of RC stars were calculated. To extend the measurable range of distance, we combined near-IR photometric data from the 2MASS survey with the deeper UKIDSS and VVV surveys. With the help of the <jats:italic>Gaia</jats:italic> parallaxes, we also removed contaminants, including dwarfs and giants. Because an SN explosion compresses the surrounding interstellar medium, the SNR region would become denser and exhibit higher extinction than the surroundings. The distance of an SNR is then recognized by the position where the extinction and its gradient is higher than that of the ambient medium.</jats:p> <jats:p><jats:italic>Results.</jats:italic> A total of 63 SNRs distances in the Galactic inner disk were determined and divided into three Levels A, B, and C with decreasing reliability. The distances to 43 SNRs are well determined with reliability A or B. The diameters and dust masses of SNRs were estimated with the obtained distance and extinction.</jats:p>

The Dust Mass of Supernova Remnants in M31

“…However, the radius of these SNRs shown in Table 1 is generally bigger than 30 pc and up to about 80 pc, indicating that they have passed the Sedov and even the snowplow phase. On the other hand, the SNRs studied by Wang et al (2020) are mostly in the Sedov phase with a radius smaller than 20 pc. Considering that the dust mass is proportional to the radius cubed, the order of magnitude difference is acceptable, in particular if the slightly higher metallicity of M31 is considered.…”

“…The dust mass ranges from about 100 to 800 M , with a peak around 205 M . This looks huge as a total amount of dust in comparison with several to tens of solar mass for a supernova remnant in the Milky Way (Wang et al 2020) with comparable metallicity. However, the radius of these SNRs shown in Table 1 is generally bigger than 30 pc and up to about 80 pc, indicating that they have passed the Sedov and even the snowplow phase.…”

“…Evidence for dust destruction in SNR shocks is mainly based on different dust mass between that within SNR and that surrounding SNR. Zhao et al (2018) and Wang et al (2020) calculated the dust masses of several tens of SNRs in the Milky Way from their extinction and found they were indeed smaller than that of average interstellar dust mass within the same volume. Unfortunately, the estimation of SNR dust mass in the Milky Way suffers serious uncertainty due to highly inhomogeneous distribution of ISM.…”

The diffuse interstellar band around 8620 Å

“…As a standard candle (Paczyński & Stanek 1998), RC stars are widely used to trace interstellar extinction (Indebetouw et al 2005;Gao et al 2009;Wang & Chen 2019) and nebular distance (Güver et al 2010;Shan et al 2018;Wang et al 2020;Chen et al 2020). RC candidates are usually selected from (J − K S , K S ) CMD with empirical borders defined by naked eyes (e.g., Wang et al 2020;Chen et al 2020). To exclude the contamination of other types of stars, peak colors are determined in different K S bins to form the track of RC toward a given line of sight.…”

Dust Mass Associated with the Supernova Remnant IC 443 when Emission Meets Extinction

“…In addition, the temperature also depends on the dust model. Another technique that has been used to estimate the dust mass uses the SNR-produced extinction since the extinction is proportional to the dust column density (Zhao et al 2018;Wang et al 2020). The extinction method has the advantage of building a three-dimensional extinction map so that the foreground or background clouds can be recognized (Zhao et al 2020;Green et al 2019), and it neither depends on the dust temperature.…”