Table of Contents
Heterodyne Systems
Instructions for Heterodyne Observations.
Heterodyne systems at the CSO permit high resolution spectroscopy in the atmospheric windows from 177 to 920 GHz.
Receivers
| Characteristics | |||||||
|---|---|---|---|---|---|---|---|
| Receiver | Range | IF BW | Trx | Tuning | Remarks | Status | |
| [GHz] | [GHz] | DSB [K] | |||||
| Sidecab | 230 | 177-210 | 4-8 | 40 | auto. | Low freq. subband requires add'l LO filter. Consult staff. | operational |
| 210-286 | |||||||
| 345 | 315-380 | 1-2 | 90 | manual | |||
| 460 | 382-532 | 4-8 | 40 | auto. | |||
| 650 | 620-730 | 1-2 | 230 | manual | |||
| Cassegrain | Barney | 300-410 | 4-8 | 50 | manual | limited availability | |
| 850 | 810-900 | 1-2 | 350-450 | manual | or Nasymth | limited availability | |
| | | | | | | decommissioned | |
| Measured Performance | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Receiver | Line | Freq. | SB | Y | Tsys | τ225 | ZA | Date | |
| [GHz] | SSB [K] | [deg] | |||||||
| Sidecab | 230 | 12CO(2-1) | 230.5 | Up | 220 | 0.126 | 15° | 2013-03-05 | |
| 345 | 12CO(3-2) | 345.8 | Up | 1.9 | 815 | 0.111 | 33° | 2013-04-04 | |
| 461 | 12CO(4-3) | 461.0 | Lo | 1240 | 0.059 | 17° | 2013-03-06 | ||
| 650 | |||||||||
| Cassegrain | Barney | ||||||||
| 850 | |||||||||
Notes
- All receivers are single polarization and double side band.
- Measured Tsys at indicated zenith angle (ZA).
- Observing Time estimate
-
- Tuning Instructions (Narrow band sidecab and 850 GHz receivers)
Maintenance
Spectrometers
| ID | Nchan | spacing | BW | Remarks |
|---|---|---|---|---|
| [kHz] | [GHz] | |||
| FFTS1 | 8192 | 61 | 0.5 | tunable across 4-8 GHz IF |
| 122 | 1 | |||
| FFTS2 | 4 x 8192 | 268.6 | 4 x 2 | |
| AOS5 | 4 x 2048 | 650 | 4 x 1 | four overlapping sections, 4 GHz usable BW |
- Fast Fourier Transform Spectrometer (FFTS1)
Available with all receivers. - Wideband Fast Fourier Transform Spectrometer (FFTS2)
Only available with the wide band (4-8 GHz) receivers. - Array Acousto Optic Spectrometer (AOS5)
Only available with the narrow band (1-2 GHz) 345 GHz and 650 GHz sidecab receivers, the 850 GHz receiver, and the wide band (4-8 GHz) 345 GHz receiver (Barney).
