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The project 4MOST at CRAL

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CRAL has been involved since 2014 in the design, assembly and tests of the two Low Resolution Spectrographs. The project is now fully in the Preliminary Acceptance Phase, with the PAE foreseen early in 2024.

4MOST (4-metre Multi-Object Spectroscopic Telescope) is a major new wide-field high-multiplex spectroscopic survey facility currently being designed for the VISTA telescope of ESO, with a first light foreseen in 2024.

4MOST has a broad range of science goals ranging from galactic archaeology and stellar physics to the high-energy physics, galaxy evolution, and cosmology. 4MOST will deploy 2436 fibres in a 4.1 square degree field-of-view using a positioner based on the tilting spine principle. The fibres will feed one high-resolution (R 20,000) and two medium-resolution (R 5000) spectrographs with fixed 3-channel designs and identical 6K x 6K CCD detectors. 4MOST will have a unique operation concept, in which 5-year public surveys both from the 4MOST Consortium and the ESO community will be combined and observed in parallel during each exposure. The 4MOST Facility Simulator (4FS) was developed to demonstrate the feasibility of this observing concept, showing that we can expect to observe above 50 million objects in the entire survey period and will eventually be used to plan and conduct the actual survey.

The 4MOST team @ CRAL is composed of the following members:

  • Alban REMILLIEUX, Local Project Manager (from February 2019)
  • Patrick CAILLIER, Local Project Manager (until January 2019)
  • Johan RICHARD, Local Responsible Scientist, Co-PI of the 4MOST Cosmology Survey
  • Jens-Kristian KROGAGER, Scientist (from January 2022)
  • Florence LAURENT, Optical designer
  • Karen DISSEAU, Optical engineer (until July 2022)
  • Alexandre JEANNEAU, Optical designer for spectrograph transmission measurement
  • Jean-Emmanuel MIGNIAU, Mechanical designer
  • Didier BOUDON, Mechanical designer and AIT mechanics
  • Eric DAGUISÉ, FEM computing mechanical engineer
  • Diane CHAPUIS, Mechanical designer (until July 2021)
  • Arlette PÉCONTAL, Software engineer
  • Aurélien JARNO, AIT electronics
  • Rémi GIROUD, Support for Local Project Manager (from September 2022)
  • Emmanuel PECONTAL, Scientist
  • Laurence TRESSE, 4MOST Executive Board member (until January 2021)
  • Matthew LEHNERT, 4MOST Executive Board member (from January 2021)


View online : Web page of the 4MOST Consortium