The planning for the near future of the VLT instrumentation was discussed at the Scientific Technical Committee (STC) meeting in April 2016. With the return of CRIRES+ currently planned for the first quarter of 2018, a VLT Nasmyth focus needs to be freed. ESO has investigated the available options, which essentially come down to FLAMES, UVES and VIMOS.
VIMOS to be Decommissioned in 2018
The evaluation of options was presented to the STC (document STC-570) for recommendation. All three instruments were judged to be of high scientific value and with good return. UVES remains one of the main workhorse instruments, FLAMES is currently used by the Gaia-ESO Survey and will become a critical instrument for follow-up observations of Gaia objects, when the first catalogues are released. VIMOS has two public spectroscopic surveys ongoing (VANDELS and LEGA-C), which should be finished in early 2018. The combination of MOONS and 4MOST will replace and supersede most of the FLAMES and VIMOS capabilities in the coming years.
The proposal to decommission VIMOS in early 2018 to make space for the return of the upgraded CRIRES+ was recommended (STC-573, Receommendation 3) by the STC. The two ongoing VIMOS public surveys will need to be finished before the decommissioning. This implies that all available dark time in Periods 98 and 100 will be allocated to these surveys. The last period when VIMOS will be offered for regular observing programmes will be P99 (April–September 2017).
ESO has also developed guidelines for the future decommissioning of VLT instruments (see STC-569), and the next candidate instruments are NACO and FLAMES.