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This is an old revision of the document!
The receiver will be installed soon into the telescope. It is not yet available!
This is a two horn system for continuum, spectroscopy and VLBI observations. The system is currently tested and all values are preliminary.
Frequency [GHz] | Channel | Polarisation | Tcal [K] | Tsys [K] | Sensitivity [K/Jy] | SEFD [Jy] | Aperture Eff. [%] | TMB/S [K/Jy] | Main Beam Eff. [%] | FWHM [arcsec] | Last update |
---|---|---|---|---|---|---|---|---|---|---|---|
19.0 | 1 | LCP | 49 | 39 | 1.05 | 37 | 37 | 1.56 | 67 | 41.9 | Jan 2014 |
21.0 | 1 | LCP | 37 | 51 | 1.07 | 48 | 38 | 1.74 | 61 | 39.5 | Jan 2014 |
23.0 | 1 | LCP | 9.5 | 58 | 1.12 | 52 | 39 | 1.41 | 79 | 37.6 | Jan 2014 |
25.0 | 1 | LCP | 8.0 | 59 | 1.12 | 53 | 39 | 1.57 | 71 | 35.6 | Jan 2014 |
normalized Gain curve (G = A0 + A1·Elv + A2·Elv2) | Observed in | confirmed | ||
---|---|---|---|---|
A0 = 0.955 | A1 = 3.1E-3 | A2 = -5.3E-5 | Jan 2014 | Jan 2014 |
Comments:
RX Name | Wavelength [cm] | Frequency (center) [GHz] | Nr. of Horns |
---|---|---|---|
S13mm Double Beam RX | 1.3 | 18.0-26.0 (22.0) | 2 |
Version: | Comment | ||
1. Continuum (BW: 2 GHz) | Broad Band Continuum | ||
Horn offsets [arcsec] | Horn 1:-95.6,734.2; 2: 95.6,734.2 |
Note that the narrow line and VLBA IF channels are usually only available when the specific line version of the receiver was selected. In addition for most receivers with narrow line channels the cables at the patch board need to be connected by the receiver group.
To select different channel numbers in OBSINP, the online plot, or the toolbox the numbers have to be specified like c(1)+c(2) to add channel 1 and 2. E.g. channel 1 and 2 contain the LCP and RCP broadband channels, then "OnlPlot pen='c(1)+c(2)'" or "toolbox use='c(1)+c(2)'" will select these channels. In OBSINP the pen can be directly specified in the receiver selection menu.
Abbreviations:
SB: narrow band channel (Schmalband-Kanal), 100 MHz band width
BB: digital broad band channel (Breitband-Kanal), band width varies for different receivers
VLBA: VLBA IF, 500 MHz band width
BW: band width
TP: total power
1.3cm SFK single horn receiver | |||
---|---|---|---|
Channel | IF | Pol. | Comment |
1 | BB | LCP | TP A |
2 | BB | RCP | TP B |
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.
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)
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)
Note, that in April the Tcal was changed in the receiver. Gaps in the curves are entirely due to measurement uncertainties. T0 and Tsys were deduced from spectroscopic skydip measurements and are subject to fitting errors caused by the low signal-to-noise ratio in the spectral bins.