| [1636] | 1 | ========================
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| 2 | Tutorial #1 - Basic ASAP
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| 3 | ========================
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| 4 |
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| 5 | .. sectionauthor:: Kate Brooks
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| 6 |
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| 7 | **Main goal:** Get a basic understanding of ASAP commands to import and plot data
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| 8 |
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| 9 | Files
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| 10 | -----
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| 11 |
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| 12 | * 2008-03-12_09320-M999.rpf Data file (1.1 Mb)
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| 13 |
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| 14 |
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| 15 | Data Log
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| 16 | --------
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| 17 |
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| 18 | * ON-OFF Position switching mode with Mopra
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| 19 |
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| 20 | * 2 Scans (1 OFF and 1 ON)
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| 21 |
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| 22 | * 1 MOPS Zoom band
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| 23 |
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| 24 | Instructions
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| 25 | ------------
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| 26 |
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| 27 | 1. Work through the list of commands given in the text file to
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| 28 | calibrate data taken with the Mopra telescope. Commands
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| 29 | should be typed line-by-line into ASAP. Seek help from the
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| 30 | tutors if there are any commands you don't understand.
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| 31 |
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| 32 | To start asap simply run the following at your prompt::
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| 33 |
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| 34 | asap
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| 35 |
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| 36 | 2. Write a python script to automate the calibration procedure
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| 37 | used in step 1. Your python script should permit interaction
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| 38 | with the plotter and should be executed in a terminal (and not
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| 39 | within ASAP) with the following command::
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| 40 |
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| 41 | python -i myscript.py
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| 42 |
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| 43 | The python script to be run outside asap needs to have the following line
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| 44 | at the top of the file::
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| 45 |
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| 46 | from asap import *
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| 47 |
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| 48 | This will import all asap functionality into the "normal" python.
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| 49 |
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| 50 | Commands
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| 51 | --------
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| 52 |
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| 53 | .. code-block:: python
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| 54 |
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| 55 | # Load data file into memory and view description
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| 56 | s = scantable('2008-03-12_0932-M999.rpf')
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| 57 | print s
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| 58 |
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| 59 | # Set the plotting mode
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| 60 | plotter.set_mode(stacking='i', panelling='t')
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| 61 |
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| 62 | # Plot all raw data
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| 63 | plotter.plot(s)
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| 64 |
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| 65 | # Set the doppler convention
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| 66 | s.set_doppler('RADIO')
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| 67 |
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| 68 | # Set the rest frame
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| 69 | s.set_freqframe('LSRK')
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| 70 |
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| 71 | # Set the observed rest frequency in Hz
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| 72 | s.set_restfreqs([86243.37e6])
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| 73 |
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| 74 | # Define the channel unit
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| 75 | s.set_unit('km/s')
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| 76 |
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| 77 | # Form the quotient spectra
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| 78 | q=s.auto_quotient()
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| 79 |
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| 80 | # Average all scans in time, aligning in velocity
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| 81 | # Note: That for this dataset there is only 1 scan and so this step is redundant
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| 82 | av = q.average_time(align=True)
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| 83 |
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| 84 | # Average the two polarisations together
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| 85 | iav = av.average_pol()
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| 86 |
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| 87 | # Plot the spectrum
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| 88 | plotter.plot(iav)
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| 89 |
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| 90 | # Remove the baseline (set to 0 order). Specify the signal-free channels
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| 91 | msk = iav.create_mask([-200,-50],[50,180])
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| 92 | iav.poly_baseline(msk,0)
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| 93 | plotter.plot(iav)
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| 94 |
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| 95 | # Smooth the data with boxcar, full width = 3
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| 96 | siav = iav.smooth(kernel = 'boxcar', width = 3, insitu = False)
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| 97 | plotter.plot(siav)
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| 98 |
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| 99 | # Scale the data according to scaling fudge factor
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| 100 | # Eg. With beam efficiency of 0.49 at 86 GHz
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| 101 | iav.scale(2)
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| 102 |
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| 103 | # Make final plot for saving
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| 104 | plotter.set_range(-20,30)
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| 105 | plotter.plot(siav)
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| 106 | plotter.set_legend(mode=-1)
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| 107 | plotter.set_title(['Orion-SiO'], fontsize=18)
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| 108 | plotter.text(10,95,"SiO (2-1 v=1) at 86243.440 MHz", fontsize=12)
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| 109 | plotter.text(-19,95,"2008/03/12", fontsize=12)
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| 110 | plotter.text(-19,90,"Zoom Mode", fontsize=12)
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| 111 |
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| 112 | # Save plot as postscript file
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| 113 | plotter.save('Orion-SiO.ps')
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