The data were taken in tandem with a BCPM pulsar observation by Ingrid Stairs.
The observation used the GBT Prime Focus 1 receiver with the 800 MHz feed
installed. The IF chain was configured for a dual circular polarization observation using optical driver modules 1 and 3 and converter rack modules 1
and 5. The LO1 sky frequency was 820 MHz and the convert rack lo2 frequency
was 11155 MHz. The 50 MHz, dual polarziation, single quadrant mode of the
spectrometer was used. A single two hour scan was performed, using
30 second integrations (a total of 239 integrations are in the output
During these observations no calibration signal
injected into the IF path, so the intensity scale must be
calibrated assuming an effective system temperature.
For the spectra below, the intensity scale was set assuming a
30 K system temperature.
The spectra have 8192 channels, corresponding to a spectral resolution
of 6,104 Hz per channel.
Since the observations were performed without injection of
the noise diode signal, the normal calibration process could not
Normally the Cal noise diode signal would be injected during
a deep search for faint spectral features. The average of the
cal signal over the observation would normaly be used to
first correct for the system gain variations. In this case,
the gain variations, would not contribute signficantly to the
noise in the spectra. A more important limit on detecting
faint features are the numerous weak RFI features. These must be
detected by their intensity variations and excised before averaging.
These data were obtained by Glen Langston for Ingrid Stairs using the
The data were taken towards a pulsar, but no significant contribution
is expected from the pulsar emission.
Data were written to directory: