New Galactic supernova remnants discovered with IPHAS
  As part of a systematic search programme of a 10-degree wide strip of the
Northern Galactic plane we present preliminary evidence for the discovery of
four (and possibly five) new supernova remnants (SNRs). The pilot search area
covered the 19-20 hour right ascension zone sampling from +20 to +55 degrees in
declination using binned mosaic images from the INT Photometric H-alpha Survey
(IPHAS). The optical identification of the candidate SNRs was based mainly on
their filamentary and arc-like emission morphologies, their apparently
coherent, even if fractured structure and clear disconnection from any diffuse
neighbouring HII region type nebulosity. Follow-up optical spectroscopy was
undertaken, sampling carefully across prominent features of these faint
sources. The resulting spectra revealed typical emission line ratios for shock
excited nebulae which are characteristic of SNRs, which, along with the latest
diagnostic diagrams, strongly support the likely SNR nature of these sources:
G038.7-1.3 (IPHASX J190640.5+042819); G067.6+0.9 (IPHASX J195744.9+305306);
G066.0-0.0 (IPHASX J195749.2+290259) and G065.8-0.5 (IPHASX J195920.4+283740).
A fifth possible younger, higher density nebula SNR candidate, G067.8+0.5
(IPHASX J200002.4+305035) was discovered about 5 arcmins to the west of IPHASX
J195744.9+305306, and warrants further study. A multi-wavelength cross-check
from available archived data in the regions of these candidates was also
performed with a focus on possible radio counterparts.
