AstroTips

Some Hands on tips working with single dish radio data using Gildas:

 #The Gildas package handbook is available here: https://www.iram.fr/IRAMFR/GILDAS/doc/html/class-html/node308.html

#Once you have the science data from (single dish) telescope you can look at the data as following:

#Open Class from terminal by writing class
class

#To open the data file:

file in data_file.apex
find /all
get first
plot

#Next spectrum

get next
plot

#Find scan number

file in data_file.apex
find /scan
set scan xxx         !scan number
find
list /toc                 !list the number of spectrum in that scan

#Find spectra by offset

find /off  x  y        ! position offset from the center
list /toc

#Find spectrum by observation number

find /all
get xx                 ! observation number

#Base fitting

set window xx xx       !line window
base xx                      ! degree of baseline (0 or more)

#Find average

average /nocheck                   ! nocheck will avoid position check

average /noche /resample      ! force resample the spectra to ge average

#Plot options
Set unit  v  f              !it will plot x axis as velocity and y as Temperature

#Regrid OTF maps
file in data_file.apex
find /all

There are different ways of regridding the OTF data to a desired pixel size
1. Using table and xy_map option
2. Defining your own pixel size and writing your own scripts