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the canadian galactic plane survey ( cgps ; @xcite ) has recently completed observations of the second quadrant of the galaxy at 1420 and 408 mhz .
the images from this survey provide an unprecedented view of the extended radio continuum emission in this portion of the galaxy at arcminute - scale resolution .
this paper presents positional and flux density information on all extended sources identified in the cgps data covering @xmath0 between @xmath1 .
cross - identifications with other major catalogues of extended radio sources and optical regions are provided along with mosaic codes that will facilitate the acquisition of cgps data for individual sources from the canadian astronomy data centre ( cadc ) .
the catalogue is especially well suited as the starting point for large - scale studies of the outer galaxy , especially those focusing on the structure of the perseus and outer spiral arms , and for placing small - scale observations in their proper context .    [
cols="<,^,^,^,^,^,^,^,^,^,^,^ " , ]     three of the sources have falling ( non - thermal , @xmath2 ) spectra .
cgpse  165 is a likely extragalactic source .
it is only slightly extended at 1420 mhz , has a non - thermal spectrum and has no associated infrared emission .
particularly noteworthy though is the filamentary structure made up of cgpse 172 and 168
. both sections of this filament have falling spectrum between 408 and 1420 mhz . a combined flux density measurement yields a spectral index of @xmath3 .
this steep , non - thermal , spectral index combined with the filamentary morphology seen at both 408 and 1420 mhz makes this object a strong candidate for a new galactic snr ( g151.2 + 2.85 ) .
figure  [ fig : l112 ] shows the region near the cas  a snr .
the region is rich in optical regions and has been interpreted as being the early stages of the formation of an ob association @xcite or even being part of a much larger complex of star - forming regions @xcite .
some of the individual regions have been observed at radio wavelengths at higher resolution but the cgps data show all of the regions in context and are sensitive to the extensive extended emission .
for example , the observations of sh-2  157 by @xcite and @xcite focus only on the region around cgpse 72 and 75 , while cgpse 73 , 74 , and 78 are probably also related .
the vla survey of optically visible regions by @xcite does not include any of these regions presumably due to a combination of the angular size limit for survey targets ( @xmath5 arcmin ) and the difficulty of obtaining images close to the cas  a snr .
while cas a itself was not imaged by the drao interferometer because its high brightness makes image calibration extremely difficult @xcite , the cgps image quality at 1420 mhz for the region close to cas a is extremely high .
special data reduction techniques , described by @xcite , were used to minimize artifacts associated with the bright snr .
in addition the field centres for the fields surrounding cas a were selected so that the snr was located in the first null of the primary beam of the drao interferometer at 1420 mhz @xcite .
since the cgps observations were not directed only to the locations of the optical regions a new galactic snr , g113.0 + 0.2 ( cgpse  83 , 84 and 85 ) , was discovered at the high - longitude end of this complex @xcite .
also cgpse 87 is a newly identified faint extended radio source .
the combined infrared , line and high - resolution ( approximately 45 arcsec ) molecular line data also available for this area would make the reinvestigation of this region , in the context of it possibly being a forming ob association , particularly worthwhile .
there are a large number of optical regions with sizes ranging from 0.2 degrees up to about 0.5 degrees located around @xmath6 ( see figure  [ fig : nvsscomp ] ) .
the emission associated with these regions is encompassed by a very extended `` bowtie '' structure of which the southern portion is associated with the large optical region sh 2 - 230 .
the region around cgpse  201 ( sh 2 - 235 ) has been studied in some detail @xcite owing to its compact nature , which facilitates interferometric observations , and the fact it contains a number of embedded infrared sources .
the region around the bright source cgpse  200 ( sh 2 - 236 ) is probably worthy of a more detailed investigation beyond the existing studies which use this large as as tracer of the galactic velocity field ( e.g. , @xcite ) .
the filaments cgpse  192 , 193 , 195 and 196 are all apparently thermal emission .
cgpse  195 has a rising spectrum between 408 and 1420 mhz and infrared ( _ iras _ ) images of this area clearly show associated infrared emission .
cgpse  196 is associated with a small ridge of infrared emission which is originating from an embedded infrared source , _ iras _  05329 + 3628 within a distant molecular cloud @xcite .
there is no obvious infrared emission associated with cgpse 192 and 193 , however , given the fact the filaments are not detected at 408 mhz , they are most likely thermal emission associated with sh 2 - 230 .
the cgpse catalogue provides a summary of the extended radio emission sources detected in the second quadrant of the galaxy by the cgps at 1420 mhz and at arcminute - scale resolution .
in addition to flux density measurements at both 1420 and 408 mhz , the catalogue contains positional information and cross - identifications with other major radio and optical catalogues .
also included are mosaic codes for each source that will facilitate the retrieval of cgps data from the cadc .
the catalogue includes a number of newly identified radio continuum sources including a new galactic snr g151.2 + 2.85 .
it expands the coverage of previous catalogues of extended galactic radio sources to include essentially the entire second quadrant along the galactic plane , and corrects a number of misclassifications and inadvertent omissions of large sources from previous catalogues .
for example , cgpse  34 and 37 ( da 558 and da 568 ) were not included in the @xcite catalogue , and objects like cgps  17 and 187 are now correctly classified as regions not snrs .
the outer galaxy is an ideal region for the study of the structure of spiral arms and for the observation of the content of star - forming regions owing to the relative proximity of the sources of interest and limited confusion when compared with similar studies directed towards the inner galaxy .
we have illustrated how the radio continuum data alone from the cgps can provide new synoptic views of star forming complexes and lead to the discovery of new sources .
the entire cgps data set is a unique resource for the investigation of galactic structure and star formation and it is hoped that this catalogue will facilitate the use of the cgps data set by the wider astronomy community .
j.p . contributed to this research as part of the freshman honors program at iowa state university .
j.m . participated in this research through an undergraduate research opportunity funded by iowa state university .
the dominion radio astrophysical observatory is operated by the national research council of canada .
the canadian galactic plane survey is supported by a grant from natural science and engineering research council of canada .
green d.a . , 2006 , a catalogue of galactic supernova remnants ( 2006 april version ) , astrophysics group , cavendish laboratory , cambridge , united kingdom ( available at http://www.mrao.cam.ac.uk/surveys/snrs/ )
a new catalogue of extended radio sources has been prepared based on arcminute - resolution 1420 mhz images from the canadian galactic plane survey ( cgps ) . 
 the new catalogue provides both 1420 mhz and 408 mhz flux density measurements on sources found near the galactic plane in the second quadrant of our galaxy . 
 in addition cross - identifications are made with other major radio catalogues and information is provided to facilitate the recovery of cgps image data associated with each catalogued source . 
 numerous new radio sources are identified and the catalogue provides a comprehensive summary of both newly discovered and previously known regions and supernova remnants in the outer galaxy . 
 the catalogue should be of use both for synoptic studies of galactic structure and for placing higher resolution observations , at radio and other wavelengths , in context .    
 surveys  catalogues  galaxy : disc  radio continuum : general .