LVM172. Scan 540


Observing log information

  Object:           LVM172.
  On scan num:      540 542 544 546 548 550
  Off scan num:     541 543 545 547 549 551
  R.A.:             6.762848 hrs
  Dec.:             46.049314 deg
  On azimuth:       306.479837 deg
  On zenith dist.:  58.825033 deg
  Off azimuth:      306.463731 deg
  Off zenith dist.: 58.796003 deg
  MJD:              52293
  UTC:              0.402338
  Center freq.:     1391.998140 MHz
  Doppler:          -0.00003306
  Num. correlators: 2
  Spectrom. atten.: 34 38 dB
  Bandwidth:        10.0 MHz
  Num. channels:    1024
  Eff. integration: 1620 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 5 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:      0.008 Jy
  Lower 20% velocity: 5973.7 km/s
  Upper 20% velocity: 6326.5 km/s
   Systemic velocity: 6150.1 km/s
   Line width (20%):   352.8 km/s
  Profile integral:    2.13 Jy * km/s
                 A:    1.65
                 B:    2.35
         Ratio B/A:   1.426
  Flux integral
     velocity range:  5960.2 - 6344.5 km/s