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Deep optical observations of G 65.3+5.7

Fotis Mavromatakis·Panayotis Boumis·John Papamastorakis·Joseph Ventura
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Abstract

We present the first CCD mosaic of the supernova remnant G 65.3+5.7 in the optical emission lines of [O II] and [O III]. The new images reveal several diffuse and filamentary structures both inside and outside the extent of the remnant as defined by its X-ray and radio emission. The medium ionization line of [O III] 5007 provides the sharpest view to the system, while the remnant appears less filamentary in the emission line of [O II]. There are significant morphological differences between the two images strongly suggesting the presence of incomplete shock structures. Deep long-slit spectra were taken at several different positions of G 65.3+5.7. All spectra originate from shock heated gas, while the majority of them is characterized by large [O III]/Hbeta ratios. The sulfur line ratios indicate electron densities below ~200 cm^{-3}, while estimates of the shock velocities lie in the range of 90-140 km/s. Finally, the observed variations of the Halpha/Hbeta ratios may reflect the presence of intrinsic absorption affecting the optical spectra.

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Fotis Mavromatakis, Panayotis Boumis, John Papamastorakis, Joseph Ventura. 2002-04-04. Deep optical observations of G 65.3+5.7. https://doi.org/10.1051/0004-6361%3A20020511

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