JWST Proposal Selection Procedures

JWST proposals will be reviewed by panels of scientists from the international astronomical and planetary science communities that will make recommendations to the STScI Director. Information on the rubric can be found in Selection Criteria and Scoring System

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How STScI Conducts the Proposal Review

JWST programs are selected through competitive peer review. A broad range of scientists from the international astronomical and planetary science community evaluate and rank all submitted proposals using a well-defined set of criteria and paying special attention to any potential conflicts of interest. The review panels and the Executive Committee constitute the Telescope Allocation Committee (TAC) that recommends the science program to the STScI Director. The STScI Director is the Selecting Official for JWST. Based on the recommendations, the Director will make the final allocation of observing time. Full details on the peer review process are given in the JWST Peer Review Guide

The Review Panels

Dependent on their size, proposals in JWST Cycle 3 will be reviewed either by external panelists or by discussion-based review panels.

The Cycle 3 discussion-based (i.e., face-to-face) review is planned to comprise sixteen topical panels, one for solar system astronomy, four for exoplanets and exoplanet formation, two for stellar physics and stellar types, two for stellar populations (and the ISM), four for galaxies, two for supermassive black holes and active galaxies, and one for large scale structure of the universe. Each panel will be managed by a panel chair, and there will be one overall TAC chair overseeing the review process. Panelists are chosen based on their expertise in one or more of the areas under review by the panels. The face-to-face panels assess and grade Medium GO proposals (> 25 and ≤ 75 hours), Small GO proposals (>15 and ≤ 25 hours) and all Target of Opportunity and Survey proposals, regardless of size.  The time allocated to each panel is proportional to the time requested by the proposals assigned to that panel; there are separate allocations for Small and medium propsoals. Panels do not adjudicate Large (>75 hours) or Treasury GO proposals or AR Legacy proposals, but they will advise their chair on the scientific merit of the subset of those proposals assigned to their panel.

The remaining Very Small GO proposals (≤ 15 hours) and regular AR proposals will be distributed for external review. Those proposals will be assessed by five experts who will grade on an absolute scale against the primary criteria: scientific merit within the field, broader importance for astronomy and the strength of the data analysis plan; JWST’s unique capabilities must also be required to achieve the scientific goals. External Panels are chosen based on their expertise in one or more of the scientific topics covered by the panel. Each external panelist will receive a limited number of proposals. The proposals will be grouped by subject area; the proposals likely to be recommended to the Director for acceptance will be provided to the chair of the appropriate face-to-face panel prior to the meeting to allow them to identify potential conflicts with the proposals reviewed by the panel.

PanelScience topics
Large-scale Structure of the Universe

Cosmology, dark matter, cosmic infrared background, galaxy clusters, gravitational lensing, high-z universe, deep field surveys, large-scale structure and reionization

Supermassive Black Holes and Active GalaxiesAGN, QSOs, Seyfert galaxies, and feedback mechanisms
Galaxies and the IGMStudies of galaxies as systems including nearby galaxies, interacting galaxies, elliptical galaxies, starbursts, luminous IR galaxies (LIRGS/ULIRGS/HLIRGS), galaxy evolution, dwarf galaxies, unresolved stellar populations
Stellar Populations and the ISMResolved stellar populations, gas and dust in the Galactic interstellar medium and in nearby galaxies, H II regions, star clusters, star-forming regions
Stellar Physics and Stellar TypesStudies of individual stars including massive stars, YSOs & protostars, evolved stars, compact objects, cool stars, brown dwarfs, supernovae, and gamma-ray bursts
Exoplanets and Exoplanet Formation

Exoplanets, debris disks, protoplanetary disks

Solar SystemTrans-Neptunian objects, asteroids, comets, planets, moons

Proposals are assigned to individual reviewers based on the reviewers' expertise and based partly on the keywords given in the proposal and partly on analysis of the proposal text. 

The review panels will follow dual anonymous protocols, with the exception of a team expertise review for the highest-ranked proposals after ranking has been completed. It is important that submissions are conform to the requirements of this type of review. Failure to do so will result in the disqualification of the submission. See JWST Anonymous Proposal Reviews for more information on what is required for the Cycle 3 review.

The Executive Committee

The Executive Committee includes the TAC chair, the panel chairs from all panels, and, typically, three at-large members chosen to provide broad expertise across a wide range of scientific categories. The primary responsibility of the Executive Committee is to review Large GO proposals (> 75 hours), Treasury GO programs, Legacy AR programs and other requests for substantial resources, such as large Pure Parallel programs. The Executive Committee are provided additional input on proposals through reviews written by external Expert Reviewers and feedback from the discussion panels via the panel chair.  

The Expert Reviewers

Expert reviews provide asynchronous reviews for: (1) proposals evaluated by the Executive Committee; (2) proposals with a large number of panelists that are conflicted; (3) joint-observatory proposals. In the last case, the Expert Reviewers are drawn from the joint-observatories' user communities. 

Selection Criteria

Reviewers are instructed to focus on the science case presented in the proposal. Evaluations of JWST proposals are based on the following criteria.

Primary Criteria for All Proposals

  • The scientific merit of the program and its potential contribution to the advancement of scientific knowledge;
  • The program’s importance to astronomy in general. This should be stated explicitly in the “Scientific Justification” section of the proposal;
  • A demonstration that the unique capabilities of JWST are required to achieve the science goals of the program.

Additional Criteria for All GO Proposals

  • The rationale for selecting the type and number of targets: Reviewers will be instructed to recommend or reject proposals as they are and to refrain from object or hour trimming. Therefore, it is very important to strongly justify both the selection and the number of targets in your proposal, as well as the number of hours requested.
  • The reasonability of requested resources.
  • The technical feasibility of the project and the likelihood of success. Quantitative estimates of the expected results and the needed signal to noise ratio of the data must be provided.

Additional Criteria for Large GO, Treasury GO, and Legacy AR proposals

  • The level of coordination of the overall work described and the production of appropriate databases and/or tools.
  • The utility of the data higher-level data products and/or tools. 

Additional Criteria for Treasury GO proposals and Legacy AR Proposals

  • The extent to which the data products will enable additional scientific investigations and the importance of those investigations.
  • The level of data products produced and plans for their timely dissemination to the community. High-level science products should be made available through the MAST data archive or related channels.

Additional Criteria for Survey Proposals

  • Willingness to waive all or part of the exclusive access period. While this is not the primary criterion for acceptance or rejection, the reduced period can bring additional benefits to any proposal and will be weighed by the reviewers accordingly.
  • The TAC will evaluate the science within the context of the optimal number of targets and minimum number of targets indicated in the Special Requirements Section of the proposal.

Additional Criterion for Calibration Proposals

  • The extent to which these observations or analyses enable new types of scientific investigations with JWST and the importance of those observations.

Additional Criteria for all Archival Proposals

  • The improvement or addition of scientific knowledge with respect to the original use of the data. In particular, a strong justification must be given to reanalyze data if the new project has the same science goals as the original proposal.
  • A well-developed analysis plan describing how the scientific objectives will be realized, and its consistency with the funding level for the proposed category.

Additional Criteria for Theory Proposals

  • The extent and importance of JWST science investigations enabled by the theoretical analysis and results.
  • The level of planning for timely dissemination of theoretical results, and possibly software or tools, to the community.

Additional Criteria for Community Data Science Software Proposals

  • The relevance of the proposed software development to JWST science investigations and/or data reduction or interpretation. 
  • The level of planning for timely dissemination of the proposed software products to the community.

Next: JWST Guidelines and Checklist for Proposal Preparation

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