21cm prime focus receiver (1260-1510 MHz)

This system can be used for sensitive continuum, spectroscopy, and pulsar observations. Additionally, it will be employed in search-programs for space-debris. Be aware, that this band may be influenced by RFI. The central horn has two circular polarizations, each of the outer six horns two linear polarizations.

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
1.408 A LCP 4.5 23 1.37 17 48 1.8 63 587 Jan 2014
1.408 B RCP 4.4 22 1.37 16 48 1.8 63 587 Jan 2014
normalized Gain curve (G = A0 + A1·Elv + A2·Elv2) Observed in confirmed
A0 = 1.0A1 = 0.0A2 = 0.0Dec 2007Jan 2014

Comments:

  • Values for the other horns will follow

Version description for OBSINP

RX Name Wavelength [cm] Frequency (center) [GHz] Nr. of Horns
P217mm 7-Beam (1.26-1.51 GHz) 21.0 1.26-1.51 (1.4) 7
Version: Comment
1. Beam-Park-Mode (BW: 47 MHz) Version for space debris search
2. Continuum/Line (XFFTS) (BW: 100 MHz) Continuum/Line with the central horn (+1) only.
3. Pulsar (BW: 300 MHz) Pulsar wide band filter
4. Line with AFFTS only HI Survey
Horn offsets [arcsec] (0.0,0.0),(-785.0,453.0),(0.0,906.0),(785.0,453.0),(785.0,-453.0),(0.0,-906.0),(-785.0,-453.0)

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

21cm-7beam PFK (only 2 out of 7 horns for continuum)
Channel IF Pol. Comment
1 SB LCP central horn 1, TP A
2 SB RCP central horn 1, TP B
3 SB cross central horn 1, cos AB
4 SB cross central horn 1, sin AB
5 SB linear horn 2, TP A
6 SB linear horn 2, TP B
7 SB cross horn 2, cos AB
8 SB cross horn 2, sin AB

Spectroscopy modes and resolution

BW nchan nu Df Dv dv
MHz MHz kHz km/s km/s
100 16384 1320 6.1 1.386 1.608
100 16384 1340 6.1 1.366 1.584
100 16384 1360 6.1 1.345 1.561
100 16384 1380 6.1 1.326 1.538
100 16384 1400 6.1 1.307 1.516
100 16384 1420 6.1 1.289 1.495
100 16384 1440 6.1 1.271 1.474

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/p217mm.txt · Last modified: 2015/07/29 00:06 by bwinkel     Back to top