LVM194. Scan 1080


Observing log information

  Object:           LVM194.
  On scan num:      1080 1082
  Off scan num:     1081 1083
  R.A.:             7.674683 hrs
  Dec.:             83.791091 deg
  On azimuth:       352.403211 deg
  On zenith dist.:  53.095435 deg
  Off azimuth:      352.399540 deg
  Off zenith dist.: 53.087453 deg
  MJD:              52284
  UTC:              0.521146
  Center freq.:     1410.816107 MHz
  Doppler:          -0.00001249
  Num. correlators: 2
  Spectrom. atten.: 33 38 dB
  Bandwidth:        10.0 MHz
  Num. channels:    1024
  Eff. integration: 540 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:      0.013 Jy
  Lower 20% velocity: 1962.9 km/s
  Upper 20% velocity: 2131.9 km/s
   Systemic velocity: 2047.4 km/s
   Line width (20%):   169.1 km/s
  Profile integral:    1.45 Jy * km/s
                 A:    1.07
                 B:    2.05
         Ratio B/A:   1.909
  Flux integral
     velocity range:  1948.4 - 2149.0 km/s


low SNR, poorly defined profile edges