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SCUBA/JCMT 850 micron map of Ophiuchus

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Update: It has come to our attention that the original COMPLETE 6" pixel SCUBA maps had a calibration error, resulting in the flux per beam being undervalued by a factor of 2. This error has been corrected as of July 9th 2007 and new versions (v3) of the maps are now available through the following pages.

A new version 2 was posted April 11, 2006. This version includes a small fix to the headers which results in a 1/2 - 1 pixel shift in the map. This datafile is called OphA_850umJCMT_F_v2.fits, and has been superseded by version 3 (above).

Description:

This file includes our own observations taken with SCUBA between March 2003 and January 2005 in fast-scanning mode, as well as archival data. Flux units are in Jy per 20 arcsecond beam.

Contact Person:
Doug Johnstone, Herzberg Institute of Astrophysics
Telescope:
JCMT
Status:

Preliminary

Sampling:
Sensitivity:
40 mJy per beam
Waveband:
850 microns
Resolution:
15 arcseconds (features larger than 1.5 arcminues have been removed)
Areal Coverage:
5.5 square degrees
Map Center (Galactic):
NA
NA
Map Center (J2000):
RA = 16:28:34
Dec = -23:54:54
Downloads:
Comments on Processing:

As previously - flatfield. despike, weather, chop deconvolution (see Johnstone et al. 2000, ApJS, 131, 505)

Additionally:
- data gaussian smoothed with sigma = 1pixel (smoothing some of noise)
- large scale structure removed through creating large scale smoothed map which is subtracted from the data. This map is made by replacing all large (positive and negative) pixels by 0 (large was taken to be +/- 0.25Jy/beam) (This prevents some of the characteristic 'bowls' seen around maps that have only been smoothed and not zeroed for flattening.), followed by smoothing this map on large scales (15 pixels = 1.5arcmin). This is then removed from the original data.

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