Karen O'Neil

Set-up

• L-band
• 200Hz Bandwidth
  
• 8192 channels
  
• 2 Quad
  
• 4 samplers (total)
  
• 1 IF/pol/bank
• 3-level
  
• Linear Polarization
• Observing using position-switching technique

Summary

• Pointing corrections was less than 1'.
• All of the data has fairly ratty baselines, with approx 40-50 MHz ripples. This could cause problems for observers.
• The bandpass shapes and rms levels for the IFs/samplers for each bank were virtually identical.
• The determined velocities and fluxes for UGC 5572 agreed, within 20%, with those found by Rick Fisher in his Galaxy HI survey (and with other published values).

Observations

• Data taken on 08/09 April, 2003
  
• Data file is T_LBAND_08APR03
  

  Scan	Source	ON time	Comments
  75,76	UGC 5572	60s	RA offset=-87'
  77,78	UGC 5572	300s	RA offset=-87'
  79,80	UGC 5572	300s	RA offset=-87'
  81,82	UGC 5572	300s	RA offset=-87'

Analysis

I. Galaxy - UGC 5572

Four 600s positioned-switched observations were made of U5572. In all cases, the baseline showed considerable structure, as exemplified below:

Fig 1.UGC 5572 in Bank A for scans 74/75.

Fig 2.Baseline in Bank A for scans 74/75.

Fig 3.UGC 5572 in Bank B for scans 74/75.

Fig 4.Baseline in Bank B for scans 74/75.

The measured flux, peak, and velocity widths of UGC 5572 falls within the errors of the previously published values for both banks and all polarizations (Flux_obs = 144 Jy km/s; Flux_{Rick, others}=127-167 Jy km/s; v_obs = 655-660 km/s; v_Rick= 660 km/s). The average of all 4 scans is below:

Fig 13. Average of all scans for Bank A.

Fig 14. Average of all scans for Bank A.

Fig 15. Average of all scans for Bank B.

Fig 16. Average of all scans for Bank B.

III. RMS

The rms noise for polarizations X and Y ranged from 7 - 12 mK, with no discernable difference between the banks/IFs/samplers. The RMS of the four averaged scans for Bank A & Bank B was 4 mK for polarizations X and Y and both IFs. Assuming a Tsys of 17.5K for the two polarizations (taken from the average values) gives a theoretical value of 7 mK for one 600s scan and 4 mK for the average of the four scans. The match is quite good.