- Information for Astronomers
- General Topics*
- Gruppen Seiten*
* Log-in required
User Tools
Sidebar
information_for_astronomers:rx:p6mm
Table of Contents
6.5mm primary focus receiver (41050-49700 MHz)
This receiver was build for spectroscopic observations. Its frequency range is divided into two channels (41-45 GHz, 45-50 GHz), each with its own (linearly polarized) feed horn separate by 107 arcsec.
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 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 41.5 | A | linear | 11.0 | 170 | 0.61 | 280 | 36 | 1.3 | 47 | 23.4 | Feb 2008 |
| 44.0 | A | linear | 9.0 | 153 | 0.43 | 358 | 25 | 1.3 | 33 | 22.0 | Feb 2008 |
| 48.0 | B | linear | 7.0 | 135 | 0.28 | 498 | 17 | 1.3 | 22 | 20.5 | Feb 2008 |
| 49.0 | B | linear | 5.0 | 127 | 0.25 | 508 | 13 | 1.4 | 17 | 19.0 | Feb 2008 |
| normalized Gain curve (G = A0 + A1·Elv + A2·Elv2) | Observed in | confirmed | ||
|---|---|---|---|---|
| A0=0.68500 | A1=1.7763E-2 | A2=-2.4878E-4 | Feb 2008 | |
Comments:
- Gain curves are opacity corrected. Opacity was tau=0.12 during the observations. Values between 0.12 and 0.15 should be typical for good weather conditions at this frequency.
Version description for OBSINP
| RX Name | Wavelength [cm] | Frequency (center) [GHz] | Nr. of Horns |
|---|---|---|---|
| P6mm (41,1-49.8 GHz,6.5mm) | 0.65 | 41.05-49.8 | 2 |
| Version: | Comment | ||
| 1. Cont./Line: 41,05-45,5 GHz (BW: 500 MHz) | Continuum and spectroscopy 1st freq. range, horn 1 | ||
| 2. Cont./Line: 45,25-49,7 GHz (BW: 500 MHz) | Continuum and spectroscopy 2nd freq. range, horn 2 | ||
| Horn offsets [arcsec] | (0.0,0.0), (0.0,107.0) | ||
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
| 6.5mm PFK | |||
|---|---|---|---|
| Channel | IF | Pol. | Comment |
| 1 | BB | linear | Horn 1, TP A, 41.05-45.5 GHz |
| 2 | BB | linear | Horn 2, TP A, 45.25-49.7 GHz |
| 3 | VLBA | linear | Horn 1, TP A, 41.05-45.5 GHz |
| 4 | VLBA | linear | Horn 2, TP A, 45.25-49.7 GHz |
Spectroscopy modes and resolution
| BW | nchan | nu | Df | Dv | dv |
|---|---|---|---|---|---|
| MHz | MHz | kHz | km/s | km/s | |
| 100 | 32768 | 41000 | 3.1 | 0.022 | 0.026 |
| 100 | 32768 | 43000 | 3.1 | 0.021 | 0.025 |
| 100 | 32768 | 45000 | 3.1 | 0.020 | 0.024 |
| 100 | 32768 | 47000 | 3.1 | 0.019 | 0.023 |
| 100 | 32768 | 49000 | 3.1 | 0.019 | 0.022 |
| 500 | 32768 | 41000 | 15.3 | 0.112 | 0.129 |
| 500 | 32768 | 43000 | 15.3 | 0.106 | 0.123 |
| 500 | 32768 | 45000 | 15.3 | 0.102 | 0.118 |
| 500 | 32768 | 47000 | 15.3 | 0.097 | 0.113 |
| 500 | 32768 | 49000 | 15.3 | 0.093 | 0.108 |
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/p6mm.txt · Last modified: 2013/10/21 15:39 by bwinkel
Except where otherwise noted, content on this wiki is licensed under the following license: CC Attribution-Noncommercial-Share Alike 4.0 International
