Tidbinbilla

The following example is processing of some Tidbinbilla observations of NH$_3$ at 12 mm. Tidbinbilla has (at the time of observations) a single polarisation, but can process two IFs simultaneously. In the example, the first half of the observation was observing the (1,1) and (2,2) transitions simultaneously). The second half observed only the (4,4) transition due to bandwidth limitations. The data is position switched, observing first an reference to the west, then the source twice and finally reference to the east. Important to note, that auto_quotient should be executed using the mode `time'.

# Load the rpfits file and inspect
d = scantable('2003-03-16_082048_t0002.rpf')
print d

# Make the quotient spectra
q = d.auto_quotient(mode='time')
print q

del d

# Plot/select in velocity
q.set_freqframe('LSRK')
q.set_unit('km/s')

# Correct for gain/el effects

q.recalc_azel()  # Tid does not write the elevation
q.gain_el()
q.opacity(0.05)

# Seperate data from the (1,1)&(2,2) and (4,4) transitions
g1 = q.get_scan(range(6))     # scans 0..5
g2 = q.get_scan(range(6,12))  # scans 6..11

# Align data in velocity
g1.freq_align()
g2.freq_align()

# Average individual scans
a1 = g1.average_time()
a2 = g2.average_time()

# Rpfits file only contains a single rest frequency. Set both
a1.set_restfreqs([23694.4700e6,23722.6336e6])

plotter.plot(a1)
plotter.set_mode('i','t')

a1.auto_poly_baseline()

plotter.plot()

a1.smooth('gauss',5)
plotter.plot()



Malte Marquarding 2007-08-16