Here are some galaxies observed with the Green Bank 20 m telescope today. They were observed with repeated 5 minute on/off position switching. All were repeated three times with the exception of UGC 1149 which was only repeated twice since its flux is largest.
The data from the 20 m are placed on a public website. Here are direct links to the data pages for each team:
These are basic text (ASCII) files, and TOPCAT will open these if you let it
know you are opening an ASCII table. They can also be opened in Python (I
recommend the astropy.io.ascii package) but that will require a bit of
tweaking to handle the header at top of the data files.
Note that there are links on these Green Bank data pages to other useful information.
The 20m has dual receivers with two polarizations. It appears that one polarization is dead or has problems. On one or two of these I shifted one receiver to a different frequency band, but on most the two receivers are covering the same (or nearly the same) bandwidth.
One of the receivers has a higher system temperature than the other.
There are spikes that may be RFI, birdies, or spectrometer errors. You will have to zoom in to "see around" these in TOPCAT. Also note you have real raw baselines!
The units of flux are kelvin (K) in the data files.
Because your author likes to say 'Uppsala' he used UGC numbers. These are all relatively bright nearby galaxies. What are some more common/famous names for your galaxy? Find a pretty optical, infrared, or UV (or all of these) picture of it.
Load the calibrated ON/OFF spectrum into TOPCAT and make plots of flux vs. frequency. Which polarizations/receivers are good or bad?
Find the galaxy! Does the profile look reasonable given the baseline? Remember these are short, noisy observations. Also, which spikes are the Milky Way and which are due to problems noted above?
Use the calculated column facility to make a velocity column in TOPCAT so that you can plot your galaxy's flux vs. velocity.
Can you remove the baseline? (digitally or mentally?) In TOPCAT you can fit a linear function (see the Forms in the X-Y plotting menus). You may be able to remove a linear baseline using a fit and a calculated column.
Similarly, convert the flux to Jy. I have found or made estimates of the gain of the 20 m as 13.65 K/Jy and 14.64 K/Jy. Extra bonus points if you justify this with radiometer equations.
Estimate the total flux of your galaxy in Jy km/s. This will be easy if you have somehow removed the baseling If not, eyeball the baseline and estimate! (There are easy ways to crudely integrate using the idea of FWHM, W50, etc.)
Look up HI spectra of your galaxy in NED and compare. You may find familiar names in the references of these spectra.