Infrared Photometer/Spectrophotometer at the MPG/ESO 2.2-metre

The Infrared Photometer/Spectrophotometer was mounted at the f/35 focus of the MPG/ESO 2.2-metre telescope at La Silla Observatory in 1987.

The standard setup for this single channel infrared photometer/spectrophotometer comprised a f/35 chopping secondary mirror which was supported by an infrared top ring and spider assembly, a f/35 photometer adaptor which contained the TV acquisition and guiding system, and several detector units that could be attached to the photometer adapter (InSb and bolometer). The InSb photometers were used for the near-infrared (NIR) and were equipped with seven broadband filters and three circular variable filters (CVFs) at 1.5–2.5 μm, 2.5–4.5 μm and 4.1–5.5 μm. The bolometer photometers were used for the mid-infrared (MIR) and were equipped with ten broadband filters and one CVF at 8–14 μm.

The operation of the chopping secondary and the adaptor were controlled with two programs from a single HP 2645 terminal in the control room. Data acquisition and control of the detectors was performed via two separate HP terminals using a so-called Infra-Red Acquisition (IRA) program. The IRA program was used to set the filter and diaphragm wheels to control the telescope beam switching, to set the parameters, to handle the data acquisition and to record in either of three modes: photometry, spectroscopy and scanning.

The Infrared Photometer/Spectrophotometer at the MPG/ESO 2.2-metre telescope was decommissioned in 1994.

Infrared Photometer / Spectrophotometer at the MPG/ESO 2.2-metre

This table lists the global capabilities of the instrument. The authoritative technical specifications as offered for astronomical observations are available from the Science Operations page.

Location: Decommissioned
Telescope: MPG/ESO 2.2-metre telescope
Focus: F/35
Type: Photometer/Spectrophotometer
Wavelength coverage:

1.5–5.5 μm
8–14 μm

Spatial resolution:
Spectral resolution: R~70
First light: March 1987
Science goal:
  • Photometry
  • Spectrophotometry
  • Mapping
  • Speckle observations
Images taken with the instrument: N/A
Images of the instrument: N/A
Press Releases with the instrument: N/A
  • ESO
  • MPIA