The MSSSO Wide Field CCD H Imaging Survey

Observing Plan

Images of the southern Galactic Plane will be taken on 5 field centres. This was the original plan of the UK Schmidt photographic H survey and our field centres were chosen to correspond to theirs for comparison purposes. However, the UK Schmidt photographic H survey are now using 4 field centres but ours will not change. Those fields further north (up to =) are based on the field centres of the emission-line survey of the Milky Way by Parker, Gull & Kirschner (1979). Their survey used a photographic image tube with a resolution of and field size 7.1 in diameter.

There are 148 fields in the southern section, 30 in the northern, 19 Magellanic Cloud and intercloud fields, 35 Orion fields and approximately 10 other fields of interest. This represents an area of 6000 square degrees (cf UK Schmidt H survey of 4000 square degrees, Parker & Phillipps 1998).

Images in H, red continuum (6676/40 Å), [SII] (6732/25 Å) and [OIII] (5016/25 Å) will have in total 30 minute exposures and B (4380 Å) and V (5450 Å) images, 15 minute exposures in total. In order to remove the effects of cosmic rays and imperfections in the CCD using median filtering, it is necessary to subdivide the total exposure times, taking three 10 minute exposures per field centre for the interference filters and three 5 minute exposures for the coloured glass filters. Small shifts ( in declination) in the position of the field centre are made for each set of shorter exposures.

The observations for the survey began near the end of March, 1997. At the time of writing, approximately 50% of the southern Galactic fields were obtained in H, around 25% in continuum and 25% in [SII]. We estimate that H and red continuum images will be completed near the end of 1997.

© Copyright Astronomical Society of Australia 1997