N7753 Scan 535

Contents

Observing log information

  Object:           N7753
  On scan num:      535 537 539
  Off scan num:     536 538 540
  R.A.:             23.783879 hrs
  Dec.:             29.473146 deg
  On azimuth:       283.500721 deg
  On zenith dist.:  56.893021 deg
  Off azimuth:      283.477387 deg
  Off zenith dist.: 56.857468 deg
  MJD:              52280
  UTC:              0.111076
  Center freq.:     1396.232709 MHz
  Doppler:          -0.00008962
  Num. correlators: 2
  Spectrom. atten.: 33 40 dB
  Bandwidth:        10.0 MHz
  Num. channels:    1024
  Eff. integration: 900 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. Narrow band interference was removed from 3 channels by interpolation between the nearest valid channels

Figure 2. Measured spectrum

Measured parameters

  Peak intensity:      0.084 Jy
  Lower 20% velocity: 4943.3 km/s
  Upper 20% velocity: 5360.0 km/s
   Systemic velocity: 5151.6 km/s
   Line width (20%):   416.7 km/s
  Profile integral:   26.21 Jy * km/s
                 A:   20.32
                 B:   26.76
         Ratio B/A:   1.317
  Flux integral
     velocity range:  4758.7 - 5396.2 km/s

Comments

wing on low velocity side below 20 percent level included in flux integral