1220+061 Scan 120

Contents

Observing log information

  Object:           1220+061
  On scan num:      120 122 124 126 128 130
  Off scan num:     121 123 125 127 129 131
  R.A.:             12.377365 hrs
  Dec.:             6.012915 deg
  On azimuth:       109.431356 deg
  On zenith dist.:  58.218036 deg
  Off azimuth:      109.395279 deg
  Off zenith dist.: 58.252041 deg
  MJD:              52603
  UTC:              0.408148
  Center freq.:     1416.387207 MHz
  Doppler:          0.00008789
  Num. correlators: 2
  Spectrom. atten.: 38 38 dB
  Bandwidth:        10.0 MHz
  Num. channels:    1024
  Eff. integration: 1740 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

Edited spectrum

This spectrum is the same as Figure 1 but with 2 60-second sub-integrations manually deleted because of interference or a bad baseline.

Figure 2. Edited 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 2.

Figure 3. Measured spectrum

Measured parameters

  Peak intensity:      0.016 Jy
  Lower 20% velocity:  850.8 km/s
  Upper 20% velocity:  912.2 km/s
   Systemic velocity:  881.5 km/s
   Line width (20%):    61.5 km/s
  Profile integral:    0.70 Jy * km/s
                 A:    0.62
                 B:    0.77
         Ratio B/A:   1.234
  Flux integral
     velocity range:   841.7 -  920.5 km/s

Comments