N2748 Scan 718

Contents

Observing log information

  Object:           N2748
  On scan num:      718 720 722 724 726 728 730 732 734 736 738 740 742 744 746 748 750 752
  Off scan num:     719 721 723 725 727 729 731 733 735 737 739 741 743 745 747 749 751 753
  R.A.:             9.228550 hrs
  Dec.:             76.475765 deg
  On azimuth:       13.447981 deg
  On zenith dist.:  59.253990 deg
  Off azimuth:      13.435481 deg
  Off zenith dist.: 59.267656 deg
  MJD:              52775
  UTC:              0.618588
  Center freq.:     1413.384821 MHz
  Doppler:          -0.00004386
  Num. correlators: 2
  Spectrom. atten.: 0 0 dB
  Bandwidth:        12.5 MHz
  Num. channels:    8192
  Eff. integration: 5310 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 6 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:      0.160 Jy
  Lower 20% velocity: 1325.8 km/s
  Upper 20% velocity: 1634.0 km/s
   Systemic velocity: 1479.9 km/s
   Line width (20%):   308.2 km/s
  Profile integral:   39.59 Jy * km/s
                 A:   38.12
                 B:   41.05
         Ratio B/A:   1.077
  Flux integral
     velocity range:  1295.0 - 1664.2 km/s

Comments