ECHelle + ELECtronic camera spectrograph

The ECHelle + ELECtronic camera spectrograph (ECHELEC) was an echelle spectrograph used at the coudé focus of the ESO 1.52-metre telescope at La Silla Observatory in Chile. Before installation at La Silla Observatory in 1973, a prototype of the spectrograph was tested at the Haute-Provence Observatory in France.

The ECHELEC was used for different programmes, both by ESO staff astronomers and visiting astronomers, in the identification of X-ray sources, the study of Wolf-Rayet stars in the Magellanic Clouds, the determination of stellar rotation in open clusters, among others. It was built to produce useful results in the blue-green spectral range and to move projects from the extensively used CASPEC and CES spectrographs.

The instrument was composed of three independent units connected by two light-proof tunnels separated by about seven metres. It originally used an electronographic camera, where photographic plates had to be processed and the results were only available at the end of the night. CCDs were later used to allow online data analysis.

The ECHELEC was decommissioned from the ESO 1.52-metre telescope in the early 1990s.

The ECHELEC technical specifications

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: ESO 1.52-metre telescope
Focus: Coudé
Type: Echelle spectrograph
Wavelength range: 380–570 nm
Spatial resolution:
Spectral resolution: R ~30 000
First light: 1973
Science goal:
  • Optical identification of galactic X-ray sources
  • Stellar rotation
Images taken with the instrument: Link
Images of the instrument: Link
Press Releases with the instrument: Link
  • ESO
  • Haute-Provence Observatory