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Network Time Allocation Process

Standard Proposals

LCO's year is subdivided into two observing semesters, each 6 months long. Standard proposals from astronomers affiliated with LCO's Science Collaboration institutions are accepted every semester. The Science Collaboration partners allocate their shares of time according to their own TAC procedures. They may elect to assign some of their time to Key Projects (see below) with which they are involved.

For LCO's own share of observing time, standard proposals are accepted from astronomers affiliated with LCO's non-guaranteed-time partners: the University of California at Santa Barbara, The University of Colorado, IPAC at Caltech, and the Astrobiology Center at the University of Tokyo . Proposals are also accepted from members of LCO's scientific family: current staff, astronomers who were postdocs at LCO in the last 5 years, astronomers who were graduate students at LCO in the last 3 years, and astronomers who served on our advisory and allocation committees in the last 2 years. 

The LCO Peer Review Committee evaluates proposals on their scientific merits, and returns a ranked list of proposals plus advice on scheduling. The Director assigns time to successful proposals and contacts the authors. Time allocations to standard proposals are for a single semester only.

The most recent call for standard proposals is posted in the Announcement section of the website.

Key Project Proposals

Proposals for Key Projects will be accepted every 18 months. Key Projects are large, coherent observing programs designed to take maximum advantage of the unique attributes of the LCO network to address important astrophysical problems. Key Projects are expected to have a duration of up to three years. Astronomers affiliated with LCO's Science Collaboration institutions and those in the US Community (through the NSF-funded MSIP time) may submit proposals for Key Projects.

Key Projects generally acquire several hundred (perhaps several thousand) hours of observations, and large project teams are assembled to carry these out. These are LCO's premier science programs. Because LCO is contributing large amounts of telescope time to support Key Projects, collaborators on proposing teams from other institutions are required to commit significant resources to the effort. Such resources could be access to other facilities, or additional time on the LCO network from their own institution, or computing resources, or scientist time.

The most recent call for key project proposals is posted in the Announcement section of the website.

Director's Discretionary Time Proposals

LCO does not allocate all (expected) observing hours to TAC-reviewed science projects. Some hours are held in reserve and may be allocated at the discretion of LCO's director. These discretionary hours are intended for observations of unforeseen targets-of-opportunity. Astronomers affiliated with an institution in LCO's Science Collaboration and investigators in the US Community (through the NSF-funded MSIP time) are eligible to submit proposals for discretionary time. However, the proposals must clearly justify why the observations must be carried out more immediately than the normal proposal/review cycle allows. Proposals for discretionary time may be submitted at any time, but the time expires at the conclusion of the current semester. A standard proposal must be submitted (and approved) to sustain observations for the same science project into the new semester.

Notification of Review Decision

Standard and Key Project proposals are reviewed by a Distributed Peer Review (DPR) panel whose members are selected from the astronomical community and are not employed by LCO. Proposals recommended for scheduling by the DPR panel are awarded time by LCO's director. PIs are notified of a standard proposal's acceptance approximately 6 weeks before the start of the semester. Proposals for discretionary time are reviewed by LCO's director only. Notices of acceptance are issued as quickly as possible, but typically in less than one week.

LCO Semesters

Semester Start End Proposal Deadline TAC Meeting
A 1 February 31 July late October early December
B 1 August 31 January late April early June

If you intend to compose a proposal for the LCO network, we recommend that you consult our guidelines for writing proposals, guidelines for writing key project proposals, as well as the "Getting Started" Guide.

Create a Proposal >

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