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authorAaron LI <aly@aaronly.me>2018-08-16 19:49:11 +0800
committerAaron LI <aly@aaronly.me>2018-08-16 19:49:11 +0800
commiteee818d15b7bd33c28303a21477babb9f2d07d3a (patch)
tree2c497ee5bc57a416ec4f2818282c2f40a26a122f
parent5e07eed5df581e676ad6ea88007ba6fb757ba74a (diff)
downloadfg21sim-eee818d15b7bd33c28303a21477babb9f2d07d3a.tar.bz2
docs/guide: Improve observation simulation
-rw-r--r--docs/guide.rst68
1 files changed, 58 insertions, 10 deletions
diff --git a/docs/guide.rst b/docs/guide.rst
index 756ca83..146a29a 100644
--- a/docs/guide.rst
+++ b/docs/guide.rst
@@ -63,7 +63,7 @@ Point Sources
The sky maps of extragalactic point sources can be simulated using
these `pointsource tools`_ that were developed for use in
-`Wang et al. 2010`_.
+`Wang et al. 2010`_ .
----------------------
@@ -76,23 +76,71 @@ sky maps, the latest `SKA1-Low layout configuration`_ (released on
The `OSKAR`_ simulator is used to perform the interferometric
observations. The ``make-ska1low-model`` tool was writen to generate
-the *sky model* of the SKA1-Low for use by ``OSKAR``.
+the *telescope model* of the SKA1-Low for use by ``OSKAR``.
The simulated *visibility data* are then imaged by utilizing the
`WSClean`_ to generate the "observed" images.
-The scripts that help carry out the observation simulations can be
-found at `atoolbox/astro/oskar`_.
+1. Generate the *telescope model* for the OSKAR simulator::
+ $ mkdir telescopes
+ $ make-ska1low-model -o telescopes/ska1low.tm
-.. _`pointsource tools`:
+2. Convert the simulated sky map (``example.fits``) into *sky model*
+ for OSKAR::
+
+ $ fits2skymodel.py example.fits
+
+ The ``fits2skymodel.py`` tool will obtain the pixel size and
+ frequency from the input FITS image header.
+ This produces the OSKAR sky model file named as ``example.osm``.
+
+3. Perform the observation simulation::
+
+ $ run_oskar.py -c sim_interferometer.base.ini -l <freq>:example.osm
+
+ The ``<freq>`` is the frequency (in units of MHz) of the input
+ sky image.
+ The simulated visibility data will be located at
+ ``visibility/example.ms``.
+
+4. Create image from the visibility data::
+
+ $ wsclean.py --niter 1000000 --weight briggs \
+ --size <npix> --pixelsize <pixelsize/arcsec> \
+ --taper-gaus <2*pixelsize> --circular-beam \
+ --threshold-nsigma 2.5 \
+ --name example \
+ --ms visibility/example.ms
+
+ The created clean image is thus ``example-image.fits``.
+ The created images have unit of ``Jy/beam`` and can be converted
+ to have unit of ``K`` by using::
+
+ $ jybeam2k.py example-image.fits example-imageK.fits
+
+The above used tools that help carry out the observation
+simulations can be found at `atoolbox/astro/oskar`_.
+
+
+-------------
+Data Analysis
+-------------
+
+
+All the above mentioned tools can be found at `atoolbox/astro`_.
+
+
+.. _pointsource tools:
https://github.com/liweitianux/radio-fg-simu-tools/tree/master/pointsource
-.. _`Wang et al. 2010`_:
+.. _Wang et al. 2010:
http://adsabs.harvard.edu/abs/2010ApJ...723..620W
-.. _`SKA1-Low layout configuration`:
+.. _SKA1-Low layout configuration:
https://astronomers.skatelescope.org/wp-content/uploads/2016/09/SKA-TEL-SKO-0000422_02_SKA1_LowConfigurationCoordinates-1.pdf
-.. _`OSKAR`_:
+.. _OSKAR:
https://github.com/OxfordSKA/OSKAR
-.. _`WSClean`_:
+.. _WSClean:
https://sourceforge.net/projects/wsclean/
-.. _`atoolbox/astro/oskar`:
+.. _atoolbox/astro/oskar:
https://github.com/liweitianux/atoolbox/tree/master/astro/oskar
+.. _atoolbox/astro:
+ https://github.com/liweitianux/atoolbox/tree/master/astro