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information_for_astronomers:rx:s20mm

2cm secondary focus receiver (13600-15600 MHz)

This is a 2-channel system mainly for VLBI observations.

Calibration Information

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
14.60 A LCP 3.8 50 1.14 44 43 2.2 51 50.8 Okt 2017
14.60 B RCP 3.8 49 1.14 44 43 2.2 51 49.5 Okt 2017
normalized Gain curve (G = A0 + A1·Elv + A2·Elv2) Observed in confirmed
A0 = 0.96053A1 = 2.4319E-3A2 = -3.7304E-5Mar 2002
A0 = 0.97099A1 = 1.8327e-03A2 = -2.8674e-05Feb 2007

Comments:

  • The new gain curve (Feb 2007) was corrected for opacity.
  • If no other information about the opacity is available a typical zenith tau value of about 0.022 should do a good job.

Version description for OBSINP

RX Name Wavelength [cm] Frequency (center) [GHz] Nr. of Horns
S20mm Multifrequency RX 2.0 13.6-15.6 (14.60) 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] -761.5,56.5

Channel assignment in the MBFITS data files

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

Tcal and Tsys measurements

information_for_astronomers/rx/s20mm.txt · Last modified: 2017/10/08 20:28 by akraus