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This is an old revision of the document!
This is a 2-channel system for VLBI observations.
In fall 2013 this system will be replaced by a new double-horn receiver.
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 |
---|---|---|---|---|---|---|---|---|---|---|---|
21.73 | A | LCP | 5.1 | 78 | 0.90 | 96 | 28 | 1.8 | 47 | 36.5 | Jul 2007 |
21.73 | B | RCP | 4.9 | 84 | 0.90 | 105 | 28 | 1.8 | 47 | 36.4 | Jul 2007 |
22.23 | A | LCP | 5.0 | 91 | 0.9 | 110 | 30 | 1.8 | 47 | 36.5 | Jul 2008 |
22.23 | B | RCP | 5.0 | 88 | 0.9 | 105 | 30 | 1.8 | 47 | 36.5 | Jul 2008 |
23.05 | A | LCP | 3.4 | 83 | 0.9 | 97 | 30 | 1.8 | 48 | 36 | Jul 2008 |
23.05 | B | RCP | 3.7 | 70 | 0.9 | 91 | 30 | 1.8 | 47 | 36 | Jul 2008 |
normalized Gain curve (G = A0 + A1·Elv + A2·Elv2) | Observed in | confirmed | ||
---|---|---|---|---|
A0 = 0.95282 | A1 = 3.6092E-3 | A2 = -6.8913E-5 | Mar 2003 | |
A0 = 0.91119 | A1 = 4.7557E-3 | A2 = -6.2902E-5 | Feb 2007 |
Comments:
RX Name | Wavelength [cm] | Frequency (center) [GHz] | Nr. of Horns |
---|---|---|---|
S13mm Multifrequency RX | 1.3 | 21.7-24.4 (23.05) | 1 |
Version: | Comment | ||
1. Continuum (BW: 2 GHz) | Broad Band Continuum | ||
2. Line (BW: 100 MHz) | Spectroscopy/Continuum using narrow band IF + VLBI IF Polarimeter | ||
3. Line (BW: 500 MHz) | Spectroscopy/Continuum using VLBA IF + VLBA IF Polarimeter | ||
4. Pulsar (BW: 500 MHz) | Pulsar 500 MHz BW Version | ||
Horn offsets [arcsec] | -593.0,55.4 |
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
2cm SFK single horn receiver | |||
---|---|---|---|
Channel | IF | Pol. | Comment |
1 | SB | LCP | TP A |
2 | SB | RCP | TP B |
3 | SB | cross | cos AB |
4 | SB | cross | sin AB |
5 | VLBA | LCP | TP A |
6 | VLBA | RCP | TP B |
7 | VLBA | cross | cos AB |
8 | VLBA | cross | sin AB |
9 | BB | LCP | TP A |
10 | BB | RCP | TP B |
BW | nchan | nu | Df | Dv | dv |
---|---|---|---|---|---|
MHz | MHz | kHz | km/s | km/s | |
100 | 32768 | 22000 | 3.1 | 0.042 | 0.048 |
100 | 32768 | 23000 | 3.1 | 0.040 | 0.046 |
100 | 32768 | 24000 | 3.1 | 0.038 | 0.044 |
500 | 32768 | 22000 | 15.3 | 0.208 | 0.241 |
500 | 32768 | 23000 | 15.3 | 0.199 | 0.231 |
500 | 32768 | 24000 | 15.3 | 0.191 | 0.221 |
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)