The JCMT Plane Survey: First complete data release - emission maps and
  compact source catalogue
  We present the first data release of the James Clerk Maxwell Telescope (JCMT)
Plane Survey (JPS), the JPS Public Release 1 (JPSPR1). JPS is an 850-um
continuum survey of six fields in the northern inner Galactic Plane in a
longitude range of l=7-63, made with the Sub-millimetre Common-User Bolometer
Array 2 (SCUBA-2). This first data release consists of emission maps of the six
JPS regions with an average pixel-to-pixel noise of 7.19 mJy beam^-1, when
smoothed over the beam, and a compact-source catalogue containing 7,813
sources. The 95 per cent completeness limits of the catalogue are estimated at
0.04 Jy beam^-1 and 0.3 Jy for the peak and integrated flux densities,
respectively. The emission contained in the compact-source catalogue is 42 +- 5
per cent of the total and, apart from the large-scale (greater than 8')
emission, there is excellent correspondence with features in the 500-um
Herschel maps. We find that, with two-dimensional matching, 98 +- 2 per cent of
sources within the fields centred at l=20, 30, 40 and 50 are associated with
molecular clouds, with 91 +- 3 per cent of the l=30 and 40 sources associated
with dense molecular clumps. Matching the JPS catalogue to Herschel 70-um
sources, we find that 38 +- 1 per cent of sources show evidence of ongoing star
formation. The images and catalogue will be a valuable resource for studies of
star formation in the Galaxy and the role of environment and spiral arms in the
star formation process.
