04071+3810 Scan 2414


Observing log information

  Object:           04071+3810
  On scan num:      2414 2416 2418 2420 2422 2424
  Off scan num:     2415 2417 2419 2421 2423 2425
  R.A.:             4.175709 hrs
  Dec.:             38.311671 deg
  On azimuth:       278.879437 deg
  On zenith dist.:  22.803570 deg
  Off azimuth:      278.865919 deg
  Off zenith dist.: 22.774198 deg
  MJD:              52255
  UTC:              0.250486
  Center freq.:     1403.058525 MHz
  Doppler:          -0.00002177
  Num. correlators: 2
  Spectrom. atten.: 34 39 dB
  Bandwidth:        40.0 MHz
  Num. channels:    1024
  Eff. integration: 1500 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 10 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 4th-order least squares fit baseline removed using most of the baseline shown in Figure 2.

Figure 3. Measured spectrum

Measured parameters

  Peak intensity:      0.003 Jy
  Lower 20% velocity: 6213.6 km/s
  Upper 20% velocity: 6400.1 km/s
   Systemic velocity: 6306.8 km/s
   Line width (20%):   186.5 km/s
  Profile integral:    0.69 Jy * km/s
                 A:    1.67
                 B:    0.67
         Ratio B/A:   0.402
  Flux integral
     velocity range:  6161.8 - 6428.3 km/s


very low SNR, profile could extend further to high velocity side