N45o Scan 548


Observing log information

  Object:           N45o
  On scan num:      548
  Off scan num:     549
  R.A.:             0.234436 hrs
  Dec.:             -23.181217 deg
  On azimuth:       163.150023 deg
  On zenith dist.:  63.382909 deg
  Off azimuth:      162.994413 deg
  Off zenith dist.: 63.418567 deg
  MJD:              52241
  UTC:              0.995660
  Center freq.:     1418.079923 MHz
  Doppler:          -0.00008896
  Num. correlators: 2
  Spectrom. atten.: 32 38 dB
  Bandwidth:         5.0 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.

Figure 2. Measured spectrum

Measured parameters

  Peak intensity:      1.089 Jy
  Lower 20% velocity:  377.8 km/s
  Upper 20% velocity:  555.4 km/s
   Systemic velocity:  466.6 km/s
   Line width (20%):   177.5 km/s
  Profile integral:   159.35 Jy * km/s
                 A:   125.41
                 B:   159.01
         Ratio B/A:   1.268
  Flux integral
     velocity range:   356.5 -  576.7 km/s