Abstract -- This document explains how Principal
Investigators (PIs) can submit QSO mode proposals and observations, and
what services
can be expected from CFHT. This document is not instrument-specific and
applies to MegaPrime, WIRCam, ESPaDOnS, SITELLE, and SPIRou.
Keywords -- QSO, Regular/TOO/Snapshot programs, Deadlines, NorthStar, Exposure Time Calculators, Technical Evaluations, TAC, Ranking, QSO grade, C programs, Snapshot programs, Phase 2, PH2/K2, Observations, Sky conditions, Calibrations, Night Reports, Data reduction and distribution, Proprietary period, QSO rules, Contact information. |
The Queued Service Observing mode used at CFHT offers many advantages over Classical Observing: higher efficiency on the sky (because Remote Observers are highly trained and observe frequently), high priority given to the most important projects (i.e., those highly ranked), observations carried under constraints specified by PIs (e.g. Image Quality requirement), very short observations possible (e.g. 2 hrs), unexpected and short notice events can be observed (e.g. Gamma Ray burst). QSO started in 2001 with CFH12k, and is now used with MegaPrime (2003), WIRCam (2005), ESPaDOnS (2008), SITELLE (2015), and SPIRou (2019).
PIs interested in submitting proposals should consult the CFHT website about a month prior to the Spring and Fall equinox. When a semester opens for proposals, announcements are made on the web site and via the agencies. The deadline for submitting proposals is usually around March 21st for the "B" semester (Aug 1st to Jan 31st), and around September 21st for the "A" semester (February 1st to July 31st). Director's Discretionary Time proposals can be submitted at any time.
Proposals are submitted using the kealahou tool K1, a Phase 1 tool created at CFHT.
Each instrument has an Exposure Time Calculator that must be used to correctly calculate required exposure times. Proposals must include the exposure times and the readout time for the specific instrument, and other overheads as instructed in the instrument-specific documentation.
Grade | Grade Name | Global Priority | % of Telescope Time |
A | "Must-Do" | Highest | 30-40 |
B | "Prioritized" | Good | 70-60 |
C | "Best Effort" | Medium | N/A |
S | "Snapshot" | Lowest | N/A |
Image Quality (IQ) | Frequency (%) |
IQ ≤ 0.55" | 5 |
0.55" < IQ ≤ 0.65" | 25 |
0.65" < IQ ≤ 0.80" | 30 |
0.80" < IQ ≤ 1.0" | 25 |
1.0" < IQ ≤ 1.2" | 15 |
IQ > 1.2" | 5 |
The table below gives the average weather statistics for Mauna Kea. In general, the amount of time lost is higher during "A" semesters than during "B" semesters, in particular during the first few months of the winter when it is not unusual to see more than half the time lost to bad weather.
Sky Conditions | Frequency |
Usable Nights | ~70% |
Lost to Weather | ~20-30% |
Usable Photometric Nights | ~50% |