The 2003 version of the MERLIN User Guide is available and is the current edition. Please
let us know about any omissions, errors or things which are not clear.
Online MERLIN User Guide
Postscript (gzipped) MERLIN User Guide
PDF of MERLIN User Guide
Initial processing of raw MERLIN data (`dfiles') and conversion to FITS must be done at Jodrell Bank using local `d-programs'. For local users see the tdproc help file (you must be on a JBO Sun machine).
All further data reduction can be done in
AIPS and other commonly available packages. The MERLIN User Guide
describes the whole process in detail.
Recentnotes.txt describes any current peculiarities or bugs not documented in the MUG:
There is a separate page for proposal information
The MERLIN Archive contains partly processed continuum data (visibilities and images) which can be downloaded by ftp or supplied on tape. It also contains some flux density measurements of calibration sources, or see below:
VLBA calibrator list and the VCS1 survey (Beasley et al. 2002).
USNO Radio Reference Frame Image Database which also provides links to other surveys.
VLA calibrator list and flux densities
NOTE
Please include appropriate references in publications in recongnition of the hard work which has gone into these surveys.
Even reference sources are likely to show different structure on different scales/frequencies and may be variable.
Note that the positions used for older observations may differ from the most recent catalogues, and the MERLIN data can be shifted accordingly if required.
At 6 GHz, at the present time (Jul 2002) the flux of the calibration
source 3C84 is not well-known and is assumed to be 10-15 Jy in recent
years.
At 22 GHz, calibrator source fluxes are obtained from monitoring at the
Metsahovi observatory; please consult MERLIN staff for the appropriate
value (this is to ensure appropriate acknowledgement of unpublished
data).
Flux scale improvement
The flux densities of the common calibrator sources in the table above are generally good to 10% for the fainter sources and to 50% for the bright sources used for high-spectral-resolution bandpass calibration. If you use an estimate (AFLUX for 'dcal' in `tdproc') you can improve the flux density calibration in AIPS by using a
small runfile after loading the data.
To calculate the flux density of a point calibrator source using d-programs, see the Merlin User Guide Section 5.1. You can perform the calculation in Section 5.1.6 with a small Fortran program flux.f which you can copy and compile. Sensitivities and weights at 5-7 GHz gives C-band Tsys values for 2004-2007