U2855o Scan 103


Observing log information

  Object:           U2855o
  On scan num:      103
  Off scan num:     104
  R.A.:             3.807087 hrs
  Dec.:             70.150580 deg
  On azimuth:       348.508815 deg
  On zenith dist.:  33.126408 deg
  Off azimuth:      350.074103 deg
  Off zenith dist.: 32.719453 deg
  MJD:              52233
  UTC:              0.265880
  Center freq.:     1414.739169 MHz
  Doppler:          0.00001728
  Num. correlators: 2
  Spectrom. atten.: 38 42 dB
  Bandwidth:        10.0 MHz
  Num. channels:    1024
  Eff. integration: 300 seconds

Raw spectrum

This spectrum is the integration of all data for the scan with spectra from both polarizations added together. The spectral intensities are Ssys * (on - off) / off, where Ssys is the system temperature in Jy. The system noise flux density equivalent is calibrated for each scan with a calibration noise source firing during each scan. The cal value, in Jy, is calibrated by comparison with a number of continuum sources as described in the summary web page

Figure 1. Unedited spectrum

Measured spectrum

This is the section of spectrum measured to obtain the parameters listed below. The three horizontal dotted lines are the baseline, the peak level selected, and 20% of the peak level. The two vertical dotted lines mark the selected 20% line width edges. The solid horizontal line marks the velocity range chosen for the the line profile flux density integral. This spectrum has a second-order least squares fit baseline removed using most of the baseline shown in Figure 1. Narrow band interference was removed from 2 channels by interpolation between the nearest valid channels

Figure 2. Measured spectrum

Measured parameters

  Peak intensity:      0.215 Jy
  Lower 20% velocity:  977.6 km/s
  Upper 20% velocity: 1424.0 km/s
   Systemic velocity: 1200.8 km/s
   Line width (20%):   446.4 km/s
  Profile integral:   82.52 Jy * km/s
                 A:   63.94
                 B:   82.17
         Ratio B/A:   1.285
  Flux integral
     velocity range:   927.8 - 1470.1 km/s