The Green Bank Observatory (GBO) invites submissions of Extra-Large observing proposals (X-proposals for short) for the 1 August, 2019 proposal submission deadline. This opportunity is open for observers seeking to use the GBT, VLA and/or VLBA. Extra-Large proposals are defined as those requesting a total of more than 1000 hours of telescope time and/or extending over four or more observing semesters. Further restrictions are indicated below. Note that the earliest that successful Extra-Large projects could be scheduled is the start of Semester 2020B in August 2020. The opportunity to submit Extra-Large proposals will likely not be repeated for at least three years. A joint proposal with external facilities (e.g., HST) may be included in an Extra-Large proposal, but the total time available for the external facility is limited (see the Joint Proposals page for details).
Regular and Large proposals continue to be encouraged for Semesters 2020A and beyond. At least 50% of open skies science time on each of the GBT, VLA and VLBA will continue to be made available for Regular and Large proposals from Semester 2020B.
To be accepted, Extra-Large proposals should demonstrate outstanding science impact, a high level of scientific and technical readiness, and excellent legacy science value (the potential to generate high science impact from community use of archival data and data products).
The scientific review process for Extra-Large proposals will be different from the normal AUI Science Review Panel (SRP) / Time Allocation Committee (TAC) process. The Science Review Panels will assess the scientific potential of each Extra-Large proposal in their science area, providing comments and a coarse grading. A new X-Proposal Science Assessment Committee (XSAC) appointed by the GBO and NRAO Directors will assess the Extra-Large proposals for their scientific merit and likely legacy science value, taking into account the initial assessments from the SRPs. Observatory staff will assess each proposal for technical readiness, and the final selection of proposals will involve a face to face scientific, technical, and operations readiness review in Spring 2020.
Preference will be given to proposals which demonstrate substantial engagement with astronomers at U.S. institutions. Preference may be given to proposals with lower requirements for observatory support, and lower operational impact. The progress of Extra-Large projects that are accepted will be monitored by the GBO.
The deadline for submissions is 1 August 2019, the same as for Semester 2020A regular and large proposals. The announcement of successful Extra-Large proposals is anticipated to occur in July 2020.
Submission of Extra-Large proposals will be via the usual AUI Proposal Submission Tool (PST) with the same 10-page limit for the Scientific Justification as for Large proposals. To distinguish Extra-Large proposals from Large proposals the text “X-Proposal” must be included at the end of the title. Extra-Large proposals may request time on one or more of the GBT, VLA, and VLBA telescopes. Proposals requesting more than one telescope should submit the same scientific justification to each telescope through the PST, but include telescope-specific resources, sources, and sessions with each submission. A representative set of sources/resources/sessions should be entered into the PST with the correct total time, but a complete source list is not required at this stage.
The following additional material is also required for Extra-Large proposals and should be submitted by emailing a PDF file to email@example.com by the same 1 August deadline:
- Data Management: The data management and delivery plan, including computing resource requirements.
- Project Schedule: A set of major project milestones and schedule.
- Team Resources: The team resources (including plans for resident scientists at the Observatory).
Proposers are also encouraged to address the following:
- Project Feasibility: The demonstrated feasibility of the project (strongly suggested).
- Special Requirements: Any special requirements (such as scheduling, calibration, scanning, data processing).
- Community Engagement: How the U.S. astronomical community will be engaged in this project.
- Observing Plan: A detailed observing plan.
The ability of the proposing team to execute the data management plan, as well as the feasibility for GBO to accommodate any requests made of it in the data management plan, will be evaluated as part of the review process. Information that assists Observatory staff to assess likely operational and NRAO/GBO support implications will be welcomed as part of the additional material. This will be the focus of the final face to face technical and operations readiness reviews with the highest ranked proposal teams.
Capabilities and restrictions for Extra-Large proposals requesting GBT time
- No fixed time/date or monitoring observations
- No observations above 8 GHz
- Only standard receivers and backends
- Prime Focus 1 (342, 450, 600, 800), Prime Focus 2 (1070), L, S, C and X-band receivers
- VEGAS, VEGAS Pulsar Modes, DCR, Mark6 (for VLBI observations)