2 minute on/offs with a few galaxies

The setup was:
• An external sample clock was used (locked to the maser).
• 170 Mhz sampling made each  subband  170 Mhz wide.
• The sky center frequency was 1375 Mhz. The 2nd los were set -/+ 60 Mhz from 250 Mhz (so the subbands were centered at (1315,1435 Mhz on the sky).
• The spectrometer was configured for 10 millisecond dumps, 8192 channels, and full stokes using 32 bit outputs.
• The synchronization of the spectrometer and the telescope was done manually. For 1 of the sources the off source did not track the exact path on the dish as the on src.
• Beam 0 of alfa was used to acquire the data.

    The 2 minutes of data were averaged and the on/off -1 was computed. For each galaxy the plots show:

1. Top plot: (on/off -1) blown up around the frequency of the galaxy. The  vertical scale is in units of Tsys (this is about 3 Jy for alfa). The black and red traces are polA and polB. They have been offset for plotting purposes (the dashed black line is there 0 point). The blue line is the average of polA and pol B. It is 0 based.
2. center plot: the averaged on source bandpass for the two minutes. Black is polA, red is polB, green is stokes U, and blue is stokes V (there has been no corrections to the stokes parameters).
3. Bottom plot: This is ON/OFF -1 for the entire band. PolA is black while polB is red (polB is offset for plotting purposes). The vertical scale is in units of Tsys (about 3 jy). 100 channels (2 Mhz) have been discarded at the edge of each 170 Mhz band (where the band passes fall off to 0).

• ugc1291 (.ps)    (.pdf)    111 seconds on source
• agc110443 (.ps)  (.pdf)   120 seconds on source
• ngc1156 (.ps)    (.pdf)    64 seconds on source

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