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This receiver replaced the old 2cm secondary focus system. It is a two horn system for continuum, spectroscopy and VLBI observations. The system is currently tested and all values are preliminary.
Note, that for technical reasons, no spectroscopic frequency-switch observations are possible!
Frequency [GHz] | Feed | Polarisation | Tcal [K] | Tsys [K] | Sensitivity [K/Jy] | SEFD [Jy] | Aperture Eff. [%] | TMB/S [K/Jy] | Main Beam Eff. [%] | FWHM [arcsec] | Last update |
---|---|---|---|---|---|---|---|---|---|---|---|
13.0 | 1 | LCP | 4.2 | 55 | 1.42 | 77 | 50 | 2.13 | 66 | 58.3 | Nov 2019 |
13.0 | 1 | RCP | 4.5 | 55 | 1.42 | 78 | 50 | 2.14 | 66 | 58.3 | Nov 2019 |
15.0 | 1 | LCP | 2.5 | 59 | 1.31 | 77 | 46 | 1.97 | 66 | 52.7 | Nov 2019 |
15.0 | 1 | RCP | 2.4 | 61 | 1.30 | 80 | 46 | 1.96 | 66 | 52.5 | Nov 2019 |
17.0 | 1 | LCP | 4.1 | 64 | 1.19 | 76 | 42 | 1.80 | 66 | 48.4 | Nov 2019 |
17.0 | 1 | RCP | 4.5 | 65 | 1.17 | 76 | 41 | 1.79 | 66 | 48.6 | Nov 2019 |
normalized Gain curve (G = A0 + A1·Elv + A2·Elv2) | Observed in | confirmed | ||
---|---|---|---|---|
A0 = 0.97099 | A1 = 1.8327E-3 | A2 = -2.8674E-5 | (from old S20mm) | — |
Comments:
RX Name | Wavelength [cm] | Frequency (center) [GHz] | Nr. of Horns |
---|---|---|---|
S20mm Double Beam RX | 2.0 | 12.0-18.0 (15.0) | 2 |
Version: | Comment | ||
1. Continuum (BW: 2 GHz) | Broad Band Continuum | ||
Horn offsets (Azi, Elv, from center of SFK) | Horn 1: -525" ; 63" – Horn 2: -762" ; 63" | ||
relative offset of horn 2 from 1 (Azi, Elv) | -237" ; 0" |
The receiver delivers the data in two 2.5GHz-wide IF-subbands, which can be shifted in to cover the 12-18 GHz range.
Note, that due to technical reasons the LSR correction has to be applied via software (regridding). This will decrease the effective spectral resolution to some degree.
TODO: update numbers!
BW | nchan | nu | Df | Dv | dv |
---|---|---|---|---|---|
MHz | MHz | kHz | km/s | km/s | |
2500 | 16384 | 18000 | 152.6 | 2.541 | 2.948 |
2500 | 16384 | 20000 | 152.6 | 2.287 | 2.653 |
2500 | 16384 | 22000 | 152.6 | 2.079 | 2.412 |
2500 | 16384 | 24000 | 152.6 | 1.906 | 2.211 |
2500 | 16384 | 26000 | 152.6 | 1.759 | 2.041 |
2500 | 32768 | 18000 | 76.3 | 1.271 | 1.474 |
2500 | 32768 | 20000 | 76.3 | 1.144 | 1.327 |
2500 | 32768 | 22000 | 76.3 | 1.040 | 1.206 |
2500 | 32768 | 24000 | 76.3 | 0.953 | 1.105 |
2500 | 32768 | 26000 | 76.3 | 0.880 | 1.020 |
2500 | 65536 | 18000 | 38.1 | 0.635 | 0.737 |
2500 | 65536 | 20000 | 38.1 | 0.572 | 0.663 |
2500 | 65536 | 22000 | 38.1 | 0.520 | 0.603 |
2500 | 65536 | 24000 | 38.1 | 0.477 | 0.553 |
2500 | 65536 | 26000 | 38.1 | 0.440 | 0.510 |
BW … band width
nchan … number of spectral channels
nu … center frequency
Df … Channel separation (in frequency)
Dv … Channel separation (in velocity)
dv … Velocity resolution (dv=1.16*Dv)
TODO: update numbers!
BW | nchan | nu | Df | Dv | dv |
---|---|---|---|---|---|
MHz | MHz | kHz | km/s | km/s | |
300 | 16384 | 18000 | 18.3 | 0.305 | 0.354 |
300 | 16384 | 20000 | 18.3 | 0.274 | 0.318 |
300 | 16384 | 22000 | 18.3 | 0.250 | 0.289 |
300 | 16384 | 24000 | 18.3 | 0.229 | 0.265 |
300 | 16384 | 26000 | 18.3 | 0.211 | 0.245 |
300 | 32768 | 18000 | 9.2 | 0.152 | 0.177 |
300 | 32768 | 20000 | 9.2 | 0.137 | 0.159 |
300 | 32768 | 22000 | 9.2 | 0.125 | 0.145 |
300 | 32768 | 24000 | 9.2 | 0.114 | 0.133 |
300 | 32768 | 26000 | 9.2 | 0.106 | 0.122 |
300 | 65536 | 18000 | 4.6 | 0.076 | 0.088 |
300 | 65536 | 20000 | 4.6 | 0.069 | 0.080 |
300 | 65536 | 22000 | 4.6 | 0.062 | 0.072 |
300 | 65536 | 24000 | 4.6 | 0.057 | 0.066 |
300 | 65536 | 26000 | 4.6 | 0.053 | 0.061 |
BW … band width
nchan … number of spectral channels
nu … center frequency
Df … Channel separation (in frequency)
Dv … Channel separation (in velocity)
dv … Velocity resolution (dv=1.16*Dv)