English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Tools annual

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Presents the access of premium content as premium feature

Premium Content

Global: Zendy Plus annual

Global: Zendy Free Plan

We present results from a study of optically emitting Supernova Remnants(SNRs) in six nearby galaxies (NGC 2403, NGC 3077, NGC 4214, NGC 4395, NGC 4449and NGC 5204) based on deep narrow band H{\alpha} and [SII] images as well asspectroscopic observations. The SNR classification was based on the detectedsources that fulfill the well-established emission line flux criterion of[SII]/H{\alpha} > 0.4. This study revealed ~400 photometric SNRs down to alimiting H{\alpha} flux of 10^(-15) erg sec^(-1) cm^(-2). Spectroscopicobservations confirmed the shock-excited nature of 56 out of the 96 sourceswith ([SII]/H{\alpha})$_{phot}$> 0.3 (our limit for an SNR classification) forwhich we obtained spectra. 11 more sources were spectroscopically identified asSNRs although their photometric [SII]/H{\alpha} ratio was below 0.3. We discussthe properties of the optically-detected SNRs in our sample for different typesof galaxies and hence different environments, in order to address theirconnection with the surrounding interstellar medium. We find that there is adifference in [NII]/H{\alpha} line ratios of the SNR populations betweendifferent types of galaxies which indicates that this happens due tometallicity. We cross-correlate parameters of the optically detected SNRs([SII]/H{\alpha} ratio, luminosity) with parameters of coincident X- rayemitting SNRs, resulted from our previous studies in the same sample ofgalaxies, in order to understand their evolution and investigate possibleselection effects. We do not find a correlation between their H{\alpha} andX-ray luminosities, which we attribute to the presence of material in a widerange of temperatures. We also find evidence for a linear relation between thenumber of luminous optical SNRs (10^(37) erg sec^(-1)) and SFR in our sample ofgalaxies.

A multi-wavelength study of Supernova Remnants in six nearby galaxies. II. New optically selected Supernova Remnants