Important recent Changes (since Periods 97 and 98) regarding La Silla Instrumentation and Facilities
This section describes important changes which took place during Period 97 and 98, as well as changes expected to take place during Period 99.
Seeing and Image Quality:
- The seeing information to provide in Box 3 of the proposal form is the seeing in the V band at zenith. This ensures that the scheduling tool uniformly takes the seeing into account. Service mode users for approved programmes will enter the Image Quality for the airmass and wavelength of interest required for their observations as a constraint during Phase 2. The article by Martinez et al. "On the Dffierence between Seeing and Image Quality" describes the meaning of these two quantities and further information can be found on the Observing Conditions webpage.
The Exposure Time Calculators have been modifed accordingly and clearly distinguish between the two quantities, using a slightly modied version of the formula given in the above article. The ETCs also report on the chances of achieving the input seeing conditions and the resulting image quality.
Exposure Time Calculators:
Designated Visitor Mode:
- DVM has been offered in La Silla since Period 98. The 3-night minimum length per run remains. See the Call for Proposals for Period 99 for details.
- Large Programmes are offered again on the NTT in Period 99; however, they should not request time in the 3-month periods from October to December in 2017 and 2018, due to a prior committment.
- The Public Spectroscopic Survey PESSTO will be completed, so substantial dark and grey time is once again available on the NTT. Bright time is generally undersubscribed and proposers should consider whether their science case can successfully exploit these conditions.
- Large Programmes on the 3.6-m telescope may span up to Period 102. See the Call for Proposals for Period 99 for details.