U12173 Scan 2219


Observing log information

  Object:           U12173
  On scan num:      2219 2221 2223 2225 2227 2229
  Off scan num:     2220 2222 2224 2226 2228 2230
  R.A.:             22.731354 hrs
  Dec.:             38.379041 deg
  On azimuth:       275.898537 deg
  On zenith dist.:  15.307321 deg
  Off azimuth:      275.886302 deg
  Off zenith dist.: 15.277556 deg
  MJD:              52254
  UTC:              0.000162
  Center freq.:     1398.107357 MHz
  Doppler:          -0.00007355
  Num. correlators: 2
  Spectrom. atten.: 34 40 dB
  Bandwidth:        10.0 MHz
  Num. channels:    1024
  Eff. integration: 1560 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 7 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. Narrow band interference was removed from 2 channels by interpolation between the nearest valid channels

Figure 3. Measured spectrum

Measured parameters

  Peak intensity:      0.034 Jy
  Lower 20% velocity: 4586.6 km/s
  Upper 20% velocity: 4961.4 km/s
   Systemic velocity: 4774.0 km/s
   Line width (20%):   374.8 km/s
  Profile integral:    8.05 Jy * km/s
                 A:    4.95
                 B:    7.55
         Ratio B/A:   1.524
  Flux integral
     velocity range:  4559.5 - 4982.9 km/s