13cm secondary focus receiver (2200-2300 MHz)

This receiver was constructed for S/X VLBI observations together with the 3.6cm system. It is a single channel system (RCP) illuminated by a paraboloid mirror (with a central opening) which is built around the 3.6cm horn. There is no S130mm receiver version, but the S-band signal is available as a 5th channel of the S36mm X-band receiver (see this picture).

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
2.250 A RCP 13.6 150 0.49 306 17 354 Dez 2004
normalized Gain curve (G = A0 + A1·Elv + A2·Elv2) Observed in confirmed
A0 = 1.0A1 = 0.0A2 = 0.0Feb 2007

Comments:

  • The special configuration (tertiary mirror) leads to an additional loss of sensitivity.

Version description for OBSINP

RX Name Wavelength [cm] Frequency (center) [GHz] Nr. of Horns
S36mm + 13cm 3.6/13 7.9-9.0 (8.35)/2.4 1
Version: Comment
1. Continuum (BW: 1.1 GHz) Broad Band Continuum + Polarimeter
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: 1.1 GHz) Pulsar 1.1 GHz BW Version
5. Pulsar (BW: 500 MHz) Pulsar 500 MHz BW Version
6. Pulsar (BW: 100 MHz) Pulsar 100 MHz BW Version

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

3.6cm SFK single horn receiver with polarimeter (+13cm offset horn for Geo-VLBI)
Channel IF Pol. Comment
1 SB RCP TP A
2 SB LCP TP B
3 SB cross cos AB
4 SB cross sin AB
5 SB RCP 13cm, TP A
6 BB LCP TP A
7 BB RCP TP B
8 BB cross cos AB
9 BB cross sin AB
10 VLBA LCP TP A
11 VLBA RCP TP B
12 VLBA cross cos AB
13 VLBA cross sin AB

Spectroscopy modes and resolution

BW nchan nu Df Dv dv
MHz MHz kHz km/s km/s
100 32768 2200 3.1 0.416 0.482
100 32768 2250 3.1 0.407 0.472
100 32768 2300 3.1 0.398 0.461
500 32768 2200 15.3 2.079 2.412
500 32768 2250 15.3 2.033 2.358
500 32768 2300 15.3 1.989 2.307

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)

Tcal and Tsys measurements

 
information_for_astronomers/rx/s130mm.txt · Last modified: 2013/10/21 15:39 by bwinkel     Back to top