KFPA Re-commissioning Test Reports

The KFPA was completed and put on the antenna for pre-observing tests on October 13, 2010. Below we summarize the tests made to confirm the proper operations of the hardware and software. Most of these tests were made during maintenance days, when the GBT was stowed.

W51 On/Off observations of HC3N at 27.3 GHz. Signal Scans 89,91 of Project TKFPA_39.
Reference Scans 90,92. Noise diode values are extrapolated.

2010 November 4: TKFPA_39

Maintenance time tests of fixed frequency labels for band scan at 50 MHz. Very poor weather. Some astronomical observations in the last 20 minutes (Reduction complete).

  • Scans 89-92: Pair of W51 On/Off of NH3, HC3N lines at 27467 MHz.
  • Scans 95-98: Test of long thin map, at galactic coordinate 15d,0d, at 27.3 GHz
    • Narrow map made, no strong emission found.

sfo38Nh3-11.png sfo38Nh3-22.png
Daisy Integrated Intensity of NH3 (1,1) transition.
Data from project TKFPA_39, scan 287
Daisy Integrated Intensity of NH3 (2,2) transition:

2010 November 3: TKFPA_38

Maintenance time tests of 50 MHz performance. Frequency axis seems to be fixed. Some Astronomical observations of SFO-38, to confirm NH3 mapping with Daisy pattern scan. In particular we were interested in the noise performance as a function of position within the Daisy pattern map.

  • Scans 1-279: Maintenance time band scan with 50 MHz
  • Scans 285-289: Daisy Map observation of SFO-38. Total observing time was 9 minutes.
    • Scans 285,286: On/Off of SFO-38 (30 seconds on, 30 seconds off source)
    • Scan 287: Daisy Map in 7 beam + 1 mode. 50 MHz bandwidth (180 second duration)
    • Scans 288,289: On/Off of SFO-38 (30 seconds on, 30 seconds off source)
  • The image of scan 287 was produced with the pipeline and scripts to completely automatically produce the image.
  • A Gaussian Fit to the GBT beam shape for a point source yields a angular size of 31 arc-seconds (FWHM).
  • The Pipeline used AIPS task SDGRD with a 15 arc-second FWHM convolving function, with resulting angular resolution of the image 34.8 arc-seconds (FWHM)

Measurements of RMS noise in a single channel of the Daisy map.
No molecular lines are expected in this channel. The boxes show where the measurements of RMS noise were measured. The middle three boxes contain data from all beams, while the edge boxes have data from fewer beams. The median RMS in the boxes was 0.25K.

The noise in the outer rim of the image is produced from only one beam. The noise in the rim region is expected to be 2.6 times greater than in the central regions. In the central region, the image telescope moves almost uniformly and the noise level is nearly constant further than 1.5 arc minutes from the image edge. For this map, the average time of a beam on a location was 1.2 seconds. For the 7 beam (central) region, the integration time was 8.4 seconds. The source was at low elevation and the system temperature ranged from 56 to 70 K.

At right the RMS noise is tabulated from 5 regions at different locations along a line of constant Right Ascension. To within the measurement accuracy, the noise level is as expected.


2010 October 29: TKFPA_37

Astronomical Tests with toward TMCCP.

  • Scans 9-23: RaLongMapWithRef Mapping Observations were in the 50MHz, 7 beam + 1 mode
  • Scans 24-38: Nod observations of TMCCP at various frequencies. Performance was good at all frequencies.
  • Scans 39-43: Daisy map observations of TMCCP at 24802 MHz.

2010 October 28: TKFPA_36

Maintenance time tests. No telescope motions.

Tests of RaLongMapWithRef for pipeline. Pipeline was able to process the data.

2010 October 28: TKFPA_35

Maintenance time tests of astrid scripts and observing modes. No telescope motion.

2010 October 26: TKFPA_34

Maintenance time band scan tests. No telescope motion.
  • Scans 1-32: band scan with 800 MHz steps
  • Scans 33-157: Band scan tests with 800 and 50 MHz.

2010 October 19: TKFPA_33

Maintenance time band scan of system performance, with 800 MHz bandwidth. No Telescope motion.
  • Scans 1-59: band scan observations.
  • Scans 60-74: Zenith test map, no telescope motion. Source is named L134. 50 MHz band at 25715 MHz
  • Scans 75-91: More band scan obs at Zenith
  • Scans 97:102: 800 MHz bandwidth On-Off observations of Sgr B2 in range 22.5 to 23.9 GHz.

2010 October 16: TKFPA_32

Good observations while moving the telescope. Observations testing performance of Rx at the band edges.

  • Scans 10-17: Nod observations of TMC-CP
  • Scans 18-19: Nod observations of 3C123. Sky frequency was 27.3 GHz, the HC3N Line. Frequency labels are incorrect, but the data look very good. Good sensitivity below 27.5 GHz
  • Scans 20-25: Daisy Map observations of TMC-CP again with frequency above 26.5 GHz. It will be difficult to reduce thes data.
  • Scans 26-27: On-Off obs of TMC-CP at 18.8 GHz
  • Scans 28-51: On-Off observations of TMC-CP across whole observing band, with 800 MHz bandwidth and 700 MHz steps.
  • Scans 52-60: On-Off observations of Orion KL, with 800 MHz bandwidth. Good data in range 18250 to 20200 MHz

2010 October 13: TKFPA_31

Maintenance time tests of astrid scripts. Antenna was stowed for all observations. Two sets of simulated mapping observations of IRC10216

  • Scans 3-17: 50 MHz bandwidth observations at high frequency end of the band, 25716 MHz
  • Scans 18-32: 50 MHz bandwidth observations beyond 26.5 GHz. Frequency labels are incorrect.
-- GlenLangston - 2010-11-30
Topic attachments
I Attachment Action Size Date Who Comment
sfo38Nh3-11.pngpng sfo38Nh3-11.png manage 35 K 2010-11-30 - 15:53 GlenLangston Daisy Integrated Intensity of NH3 (1,1) transition
sfo38Nh3-22.pngpng sfo38Nh3-22.png manage 40 K 2010-11-30 - 15:54 GlenLangston Daisy Integrated Intensity of NH3 (2,2) transition
sfo38RmsNoiseBoxes.pngpng sfo38RmsNoiseBoxes.png manage 46 K 2010-11-30 - 15:54 GlenLangston Measurements of RMS noise in regions of Daisy map
w51Hc3n27.3GHz.pngpng w51Hc3n27.3GHz.png manage 31 K 2010-11-30 - 10:42 GlenLangston W51 obs of HC3N at 27.3 GHz
Topic revision: r5 - 2010-12-01, GlenLangston
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