Phase I Overview

Applications for time on Gemini are made through National Time Allocation Committees (NTACs) which are individually responsible for scientific and technical assessment and for making recommendations to the Gemini Observatory that time be awarded. Proposals will be solicited by Gemini every 6 months in early March and September; details of the submission and review process vary from partner to partner. Links to partner-specific information are contained in the following table:

	US Phase I info		Chilean Phase I info
	UK Phase I info		Argentinean Phase I info
	Canadian Phase I info		Brazilian Phase I info
	Australian Phase I info		University of Hawaii Phase I info

The Phase I process is supported by staff in the National Gemini Offices (NGOs). Use of the Gemini Help Desk is strongly recommended as the method for contacting NGO staff to make queries, request information etc. Proposals from outside of the Gemini community must be submitted through one of the NTACs.

International collaborations ("joint proposals"), where time is being sought from several partner countries, must be submitted using the Gemini Phase I Tool (PIT) even if the proposal involves partners that offer other submission mechanisms. The PIT supports automatic submission to multiple partners at once. (See the joint proposal instructions for more details).

In normal operations, application may be made for classical or queue mode observations. Classical mode observations are scheduled on specific dates, similar to most ground-based observatories, and generally are carried out by the investigators visiting the telescopes. Queue mode observations are defined in detail by the applicants and executed on their behalf by the Gemini staff. This mode offers the potential of better matching observations to the prevailing conditions (e.g. image quality, sky background, cloud cover) and execution of Target of Opportunity observations for classes of targets whose coordinates are not known at the time of proposal submission.

A schematic view of the Phase I process illustrates some aspects that differ from those on many other telescopes:

The NTAC outputs, comprising the rankings, recommended time awards and the full proposals, are sent electronically to Gemini Observatory where they are merged together, and with the output of the Gemini staff TAC, to produce a draft schedule and draft queue. (More details about the merging process and the instructions to the NTAC members are available). For the merging to work effectively, the group of top-rated proposals that would fill that partners share of the time available should contain a reasonable balance in terms of the observing constraints requested. For example, not all proposals can request the best image quality conditions or dark time. In fact, more proposals than the minimum are transmitted to provide flexibility during merging.

The draft schedule and draft queue, along with notification of any target or scheduling conflicts identified during the merging process, are sent to the International Time Allocation Committee (ITAC; see terms of reference). The ITAC consists of representatives from each NTAC and from Gemini Observatory. After resolution of any conflicts and consideration of duplicate and joint proposals, the recommended schedule, queue and the position of the queue bands are forwarded to the Gemini Director for final approval. The final schedule and queue will be published on the web. The following information is considered public and will be included: PI name, partner country, proposal title and abstract, instrument.

Starting in 2004A, queue programs assigned by the ITAC into queue Science Ranking Band 1 will be eligible for rollover into the next semester, for no more than two consecutive semesters, in order to increase the likelihood of program completion. Eligibility for rollover of 2004A programs will be decided at the 2004A ITAC (for rollover into 2004B) and so forth. Rollover will apply to queue programs only. The relevant ITAC representatives have the right to recommend withdrawal of execution (and rollover) status.

Scientific and technical feedback to the investigators about their proposal is generated by each NGO/NTAC. Notification of the award of time (or a place in the queue) is generated by Gemini Observatory and sent to each NGO/NTAC for onward distribution to the investigators. The formal handover of responsibility for supporting the investigators, from the NGO to Gemini Observatory, takes place upon transmission to Gemini of the final detailed Phase II program (NGOs initially iterate with PI's to specify the phase II observations using the Gemini Observing Tool).

The two phases of the proposal process seen from the perspective of applicants are shown schematically in the following generic diagram:

Each proposal recommended for time is sent by the NTACs/NGOs to Gemini as an XML (eXtensible Markup Language) document consisting of attribute/value pairs that encode the proposal information (e.g. PI name, target co-ordinates, instrument resources, scientific case) and, if required, associated files with figures etc. The Gemini Phase I Tool (PIT) automatically generates the XML file. Partners who have chosen to use their own web-based or other proposal systems must translate their internal formats into the correct XML structures. The XML format is described in a document package and has been defined to be of generic use for observatories other than Gemini.

Phase I queue proposals require the specification of observing condition constraints which define the poorest acceptable conditions under which the observations can be executed. In addition, all queue and classical observations require the use of one or more wavefront sensor (WFS) stars for fast guiding, primary mirror active optics control and/or adaptive optics. As the technical feasibility of a proposal relies in part on the availability of WFS stars, all proposals sent by the NTACs/NGOs to Gemini must identify WFS stars in the proposal. The Gemini Phase I software contains a tool that will automatically apply the relevant brightness and field-of-view constraints and select WFS stars given the science target co-ordinates. The alternative proposal systems used by some partners have other provisions for selecting WFS stars (in some cases these may be added by NGO staff after submission of the proposal; please check with your NGO if you are unsure).

Last update April 23 2007; Sandy Leggett (previously August 31, 2006; Rachel Mason & Bob Blum)