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In this paper we present new optical observations of the galaxy NGC 185intended to reveal the status of supernova remnants (SNRs) in this dwarfcompanion of the Andromeda galaxy. Previously, it was reported that this galaxyhosts one SNR. Our deep photometric study with the 2m telescope at RozhenNational Astronomical Observatory using narrow-band H$\alpha$ and [SII] filtersrevealed complex structure of the interstellar medium in the center of thegalaxy. To confirm the classification and to study the kinematics of thedetected nebulae, we carried out spectroscopic observations using the SCORPIOmulti-mode spectrograph at the 6m telescope at the Special AstrophysicalObservatory of the Russian Academy of Science, both in low- and high-resolutionmodes. We also searched the archival X-ray and radio data for counterparts ofthe candidate SNRs identified by our optical observations. Our observationsimply the presence of one more SNR, one possible HII region previouslycataloged as part of an SNR, and the presence of an additional source of shockionization in one low-brightness PN. We detected enhanced [SII]/H_alpha and[NII]/H_alpha line ratios, as well as relatively high (up to 90 km s$^{-1}$)expansion velocities of the two observed nebulae, motivating theirclassification as SNRs (with diameters of 45 pc and 50 pc), confirmed by bothphotometric and spectral observations. The estimated electron density ofemission nebulae is 30 - 200 cm$^{-3}$. Archival XMM-Newton observationsindicate the presence of an extended, low-brightness, soft source in projectionof one of the optical SNRs, whereas the archival VLA radio image shows weak,unresolved emission in the center of NGC 185.

Revealing the nature of central emission nebulae in the dwarf galaxy NGC 185