This section describes important changes which took place during Period 104 and 105, as well as changes expected to take place during Period 106.

Proposal anonymisation:

In sight of the future deployment of Dual-Anonymous Peer Review (DAPR), ESO strongly encourages applicants to formulate the scientific rationales of their proposals following the anonymisation rules and examples described in this link, which also gives a detailed description of the DAPR paradigm. Period 106 will be used as a dry run, both to make the community aware of the upcoming implementation of DAPR and to test its practical, procedural and policy aspects. In Period 106, proposal anonymisation will not be mandatory. Nevertheless, applicants should take advantage of the dry run to practice with the new writing style required by the dual-anonymous paradigm, following the guidelines provided in the link above.

p1: A new tool for proposal preparation and submission:

A new tool for the preparation and submission of observing proposals was deployed in Period 105. It represents the first part of a broader re-haul of the ESO Phase 1 system (p1) that also entails a significant modernisation of the Observing Programmes Committee, refereeing process, and related tools. The new p1 system is web-based, resembles the recent p2 tool. Users are encouraged to get familiarised with the new system using the p1demo tool well before the proposal deadline.

Large Programs:

Large Programmes, those that require 100 hours or more, are accepted for Period 106. Since Period 104, Large Programmes can only be submitted in even Periods, i.e., Periods with the proposal submission deadline in March/April. A number of instrument restrictions for Large or Monitoring Programs apply. We refer the reader to Sect. 4.4 in the Call for Proposals Period 106.

Introduction of turbulence categories:

With the advent of instruments using new adaptive optics (AO) modes, new turbulence parameters need to be taken into account in order to properly schedule observations and ensure that their science goals are achieved. These parameters include the coherence time and the fraction of turbulence taking place in the atmospheric ground layer, in addition to the seeing. Such a change was initiated for the SPHERE instrument in Period 103.

In Period 105, the new turbulence constraints were standardised to the turbulence conditions required by all instruments and modes, whether they are seeing-limited or AO-assisted. Users are encouraged to read the general description of these changes for Phase 1 and Phase 2 on the Observing Conditions webpage, as well as instrument User Manuals for specifics per instrument. The Exposure Time Calculators have been updated to reflect these changes.

In addition, interested readers should refer to the article by Martinez et al. 2010 (The ESO Messenger 141, 5) "On the Difference between Seeing and Image Quality" which describes the meaning of these two quantities.

Instruments and Facilities

• NIRPS:  the Front End Adaptive Optics and the Back End of the Near Infra-Red Planet  Searcher are expected  to  be  commissioned at  the  3.6-m telescope during two periods in 2020 and the 1st quarter of 2021, respectively. The installation of NIRPS is not expected to affect the operations of HARPS in Period 106.
• SoFI and EFOSC2:  Monitoring and Large Programmes with SOFI and EFOSC2 are not accepted in Period 106, as the installation and commissioning of SoXS - the Son of X-Shooter - is expected to start during the first quarter of 2021.
• SoFI will be decommissioned in the first half of Period 106 to allow the installation of SoXS.
  
• ULTRACAM:
  
  • ULTRACAM is a high-speed imaging photometer designed to study faint astronomical objects at high temporal resolutions. ULTRACAM employs two dichroic beamsplitters and three frame-transfer CCD cameras to provide optical imaging with a field-of-view of 60 and at frame rates of up to 300 Hz simultaneously in the u'g'r', u'g'i' or u'g'z' bands.
    
  • This PI instrument is offered to the ESO community for up to 5% of the observing time at the NTT in Period 106. Large Programmes will not be accepted.
    
  • Operation of this PI instrument requires the presence of the instrument team, so ULTRACAM programmes will preferentially be scheduled contiguously on periods of several nights. For questions on the instrument and observation strategies, users shall contact the instrument PI, Prof. Vik Dhillon (vik.dhillon[AT]sheeld.ac.uk), at least two weeks prior to submitting their proposal.
  • The ULTRACAM consortium is committed to support the PIs and observers from the ESO community that have been awarded telescope time with ULTRACAM. The ULTRACAM team will support the execution of the observations and the subsequent data reduction to allow the scientic exploitation of the data obtained with ULTRACAM.
  • Proposers must check that their planned observations do not duplicate any protected targets specified for ULTRACAM in the Period 106 GTO target protection webpages.