Towards 3rd Generation Calibration in Radio Astronomy
Presently the SSSC are geared up towards the teaching and qualification process
for the
SKADS/MCCT workshop which will be held in Nancay, France, from 27 September
to 10 October 2009.
If you are a prospective participant you are encouraged to work through your own
selection of Open Challenges. Further information can be found in the FAQ and Links sections.
If you have any questions or bug reports regarding the site then please contact Ian Heywood:
ianh@astro.ox.ac.uk
Each item in the list of Open Challenges is based on a data-set (MS)
with simulated uv-data. These are generated for an existing instrument
(e.g. the WSRT), using a particular Local Source Model (e.g. a point
source), and corrupted with a specific set of instrumental errors
(e.g. antenna phases that vary sinusoidally with time).
The "difficulty" of an item is indicated with a rating (one or more
stars). You will notice that the first ones are variations on the theme
of a single point source in the centre of the field. Since we are
working hard to stay just ahead of you, more interesting items will
appear by the time you are ready for them.
The PURR log in the first item will guide you trough the various
steps: Looking at the uv-data, trying to subtract the LSM from it, and
solving for the corrupting instrumental errors. In principle, you can
use any 2nd generation data reduction package of your choice to do all
this. But in view of the 3GC Challenges to come, we really recommend
that you invest the time to master MeqTrees.
Whatever tools you use, we ask you to report your findings in the form
of PURR logs (see below), marked with your name, email address and
other useful information. Please send your PURR logs to Jan Noordam:
noordam@astron.nl
While we will give points for zeal (e.g. if you work through all the
available Challenges), we are more interested in other traits (see
also below). We will be particularly impressed with people who go one
step further, and generate new Open Challenges of their own. For
instance by making interesting variations on the ones that are already
there. Instructions for doing so are in another PURR log in the first
Challenge. With your consent, we will put your new items on the SSSC
page, for others to play with, and to make their own variations on.
If you get carried away, and want to use your special skills to
contribute something to our tools, we will be pleased to offer you
some suggestions.
Somewhere in August, we will introduce some special Challenges that
deal with the two main themes of our workshop, i.e. station beamshapes
(EJones) and ionosphere (ZJones and FJones). For some of you, this
might be the moment to specialize a bit.
This is all you need to know to start. We hope that you will enjoy
this exercise, and feel that it opens new ways of doing things, and
particularly of doing them together. We very much look forward to
getting to know you, and to see what you can do.
(One more thing: If you know anyone else who would enjoy participating
in this, just pass on this information, and tell him or her to start
sending in PURR logs. Registration is not necessary.)
Jan Noordam
Ian Heywood