Instructions for Visiting Astronomers

Observing runs in visitor mode (all instruments)

  • Visiting astronomers should follow the instructions given in in this page
  • General information for visiting astronomers can be found here
  • At the end of your observing run, please do not forget to submit your End of Mission report!

VIMOS observing runs in visitor mode

Observing programs in MOS mode

Due to the rule that MOS observations should be carried out within 2 hof the meridian, in Visitor Mode it is desirable that the targets are uniformly distributed in RA for the night(s) of the observations. If this is not the case, users should apply for service mode observations. Exceptionally, in visitor mode one may choose to violate the requirement to observe within 2h of the meridian.

For operational reasons a maximum number of 7 visitor masks (per quadrant) will be made available in the instrument each night.

Pre-imaging with VIMOS is mandatory in both visitor and service modes for observation in MOS mode, and is carried out only in service mode.

Normally, users should submit OBs for mask preparation well before their observing run, so that masks can be manufactured before visitor arrival (see this page).Exceptionally, limited additional support is offered for mask preparation on the mountain, up to 3 sets of masks per night, to be prepared at least 48 hrs in advance.

After submitting MOS OBs for the visitor mode run, please send an e-mail to in order to inform the VIMOS support astronomers about the new masks to be manufactured. Please provide information on: (1) Programme ID,(2) number of OBs and number of mask sets (each mask set has 4 masks, one for each of the 4 quadrants) and (3) the date of the first night of observations.

Observing programs in IFU mode

For IFU observation, sky flats are not part of the calibration plans. However they can be requested during a visitor run.Please inform your support astronomers in advance that you will need this special calibrations.