Karen O'Neil, Frank Ghigo

Set-up

• L-band
• 12.5MHz Bandwidth
  
• 2048 lags
  
• 1 Quad
  
• 8 samplers
  
• 9-level
  
• Linear Polarization
• Band centers offset by 5 MHZ (IF2=13075,13080,13085,13090)
• Observing using position-switching technique

Summary

• Pointing correction was less than 1'.
• No baseline ripples were seen in either bandpass
• The inferred sensitivity at 1.4GHz was 1.72 and 1.82 K/Jy for polarizations X & Y, respectively.
• The bandpass shapes and rms levels for the four IFs were virtually identical and equal to the theoretical prediction.
• The determined velocities and fluxes for UGC 9179 agreed, within errors, with those found by Rick Fisher in his Galaxy HI survey
• No significant RFI was seen.
• This mode is ready for general use.

Observations

• Data taken on 19 Feb, 2003
  
• Data file is T_LBAND_19FEB03
  

  Scan	Source	ON time	Comments
  65,66	UGC 9179	300s	RA offset=-87'
  67,68	UGC 9179	300s	RA offset=-87'
  69,70	UGC 9179	300s	RA offset=-87'
  71,72	UGC 9179	300s	RA offset=-87'
  73,74	UGC 9179	300s	RA offset=-87'
  75,76	3C295	300s	Position Switched observation; RA offset=-87'

Analysis

I. Calibrator - 3C295

Gain inferred from this calibrator was 1.72 & 1.82 for pol. X & Y, respectively. The reduced spectrum for IF1 is shown below.

Fig. 1. IF1 for the spectrum of 3C295

Other 3C295 plots available are:

• IF 2
• IF 3
• IF 4

II. Galaxy - UGC 9197o

Five 600s positioned-switched observations were made of U9197o. Unfortunately, the 5MHz shift between IFs resulted in the source not lying in the band for any but the 1st IF. Rms calculations, though, could be done for all four IFs.

The measured flux, peak, and velocity widths of UGC 9179 falls within the errors of the flux published by Rick Fisher for all IFS and all polarizations. Example spectra are below:

Fig 2. IF1, average of all scans

Other U9179 plots available are:

• IF1, scan 66, blown up to see detail in galaxy
• IF1, average of all scans, blown up to see detail in galaxy

III. RMS

The rms noise for polarizations X and Y ranged from 0.012 - 0.013, with no discernable difference between the four IFs. Assuming a Tsys of 18.3 K for both polarizations (taken from the average values) gives a theoretical value of 13.9 mK, in good agreement with the measured values. The RMS of the averaged scans also followed the thoeretical 1/(sqrt(t) behavior as the scans were averaged. Plots of the baselines are below.

Fig 3. If1, all plots averaged, blomn up for baseline details

Other baselines plots available are:

• IF1, scan 66, blown up to see detail in baseline
• IF2, scan 66, blown up to see detail in baseline
• IF3, scan 66, blown up to see detail in baseline
• IF4, scan 66, blown up to see detail in baseline
• IF3, all scans averaged, blown up to see detail in baseline
• IF4, all scans averaged, blown up to see detail in baseline