Object: NGC7771 On scan num: 135 137 139 141 Off scan num: 136 138 140 142 R.A.: 23.856899 hrs Dec.: 20.111639 deg On azimuth: 198.435866 deg On zenith dist.: 19.057186 deg Off azimuth: 198.446589 deg Off zenith dist.: 19.058160 deg MJD: 52456 UTC: 0.455891 Center freq.: 1400.555483 MHz Doppler: 0.00009204 Num. correlators: 2 Spectrom. atten.: 41 40 dB Bandwidth: 10.0 MHz Num. channels: 1024 Eff. integration: 1200 seconds
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
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.
Peak intensity: 0.041 Jy Lower 20% velocity: 3997.0 km/s Upper 20% velocity: 4588.0 km/s Systemic velocity: 4292.5 km/s Line width (20%): 591.0 km/s Profile integral: 17.62 Jy * km/s A: 17.67 B: 19.11 Ratio B/A: 1.081 Flux integral velocity range: 3954.7 - 4722.5 km/s
messy profile, shallow high velocity wing