- Information for Astronomers
- General Topics*
- Gruppen Seiten*
* Log-in required
User Tools
Sidebar
information_for_astronomers:rx:s7mm
This is an old revision of the document!
Table of Contents
7mm secondary focus receiver (41600-44400 MHz)
This is a 2-channel system for VLBI observations. The whole receiver was reconditioned in late 2012.
A new double-horn system is under construction. It should become operational in 2014.
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 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 42.0 | A | LCP | 13.8 | 108 | 0.53 | 196 | 19 | 1.5 | 36 | 19.8 | Mar 2009 |
| 42.0 | B | RCP | 12.2 | 131 | 0.53 | 248 | 19 | 1.5 | 35 | 19.8 | Mar 2009 |
| normalized Gain curve (G = A0 + A1·Elv + A2·Elv2) | Observed in | confirmed | ||
|---|---|---|---|---|
| A0 = 0.8806 | A1 = 5.8673E-3 | A2 = -7.1243E-05 | Dec 2007 | |
| A0 = 0.8800 | A1 = 6.9970E-3 | A2 = -1.0210E-04 | Mar 2009 | |
Comments:
- The new gain curves were corrected for opacity.
- Opacity correction was done with a zenith opacity of 0.08. Typical zenith opacities under good weather conditions are around 0.07 to 0.1 at 42 GHz.
- For informations about the old parameters please contact Uwe Bach (ubach_at_mpifr.de).
Version description for OBSINP
| RX Name | Wavelength [cm] | Frequency (center) [GHz] | Nr. of Horns |
|---|---|---|---|
| S7mm Multifrequency RX | 0.7 | 41.6-44.4 (42.9) | 1 |
| Version: | Comment | ||
| 1. Continuum (BW: 2 GHz) | Broad Band Continuum | ||
| 2. Line (BW: 500 MHz) | Spectroscopy/Continuum using VLBA IF + VLBA IF Polarimeter | ||
| 3. Pulsar (BW: 500 MHz) | Pulsar 500 MHz BW Version | ||
| Horn offsets [arcsec] | -466.2,58.6 | ||
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
| 7mm 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
TODO
information_for_astronomers/rx/s7mm.1363093819.txt.gz · Last modified: 2013/09/30 13:58 (external edit)
Except where otherwise noted, content on this wiki is licensed under the following license: CC Attribution-Noncommercial-Share Alike 4.0 International
