JWST Proposal Implementation and Execution

Accepted JWST observations will be incorporated in the long range plan and checked for technical feasibility. STScI will endeavor to schedule observations within the nominal cycle boundaries. However, scheduling may extend into later cycles. Principal Investigators should ensure that any scientifically-required scheduling constraints are included in the proposal.

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Once the STScI director has approved the full list of JWST programs for the next cycle, a first version of the long range plan (LRP) will be constructed with the information provided in the single-stream proposals; programs exempted from the nominal single-stream process will be incorporated using approximated scheduling windows determined from their target lists. This first draft of the LRP enables the identification of scheduling conflicts between approved programs together with other issues not flagged by APT. Reviews of the approved programs may be prioritized based on the LRP scheduling window, with programs with targets that have scheduling windows early in the cycle receiving highest priority. Complex large programs with timing constraints (e.g., large mosaic images, exoplanet transit observations, coordinated observations with other facilties) impose significant constraints on the LRP; thus, it is important to incorporate these into the schedule as early as possible. 

All programs will be reviewed to ensure that the submitted observing plan is consistent with the TAC allocation and checked for potential duplications. Additionally, programs which are likely to cause severe detector persistence may be flagged so that they may be scheduled so as not to impact subsequent programs. The scheduling process aims to optimize the overall JWST efficiency. Unless there are compelling scientific arguments, STScI will not advance or postpone the scheduling of individual programs.

Unlike some HST instruments, JWST instruments do not require 'health and safety' reviews. Challenging JWST programs may require additional reviews, which will be completed after the compilation of the LRP.  These operationally-complex programs are primarily those which require target acquisitions such as coronagraphy and spectroscopy. In particular, NIRSpec MOS program updates must be submitted at least 8 weeks before the assigned plan window start, to allow ample time for review. 

After the initial program reviews and construction of the LRP, additional reviews by program coordinators and instrument scientists to further validate each program could be executed throughout the cycle without impacting the schedule. Any significant changes to an approved JWST program must be evaluated by the telescope time review board and will only be approved if they significantly improve the scientific return of the program.

Scheduling observations

The prime criterion applied in scheduling JWST observations is maximizing the overall efficiency. Scheduling will also aim to minimize observations in the micrometeoroid avoidance zone (MAZ). Priority scheduling will be enabled for programs where there is a clear scientific justification for scheduling within a particular time window. All other observations will be given equal weight in constructing the Long Range Plan and the observing schedule.

Program execution

Proposers should be aware that after acceptance of a proposal, the actual execution of the observations may in some cases prove impossible. Possible reasons include:

  • The accepted observation may be found to be infeasible or extremely difficult for technical reasons only discovered after the approval; ToO and time-critical observations can be particularly complex to plan and execute, and will be completed only to the extent that circumstances allow.
  • The observing mode or instrument selected may not be operational.
  • Suitable guide stars or scheduling opportunities may not exist.
  • If the total MAZ usage exceeds 15% of the cycle time, certain observations or programs may be delayed to future cycles; if, after mitigation, the total usage remains above 20%, observations will be disallowed, based on the relative ranking of programs from the TAC review.
  • Survey programs and pure parallel programs are not guaranteed to be scheduled.
  • Anomalies or failures that develop within the observatory may preclude certain observations.

The STScI Director reserves the right to disallow at any time any or all observations of an approved program if it is demonstrated that incorrect or incomplete information was provided in the proposal that may have significantly influenced the approval recommendation by the review panels or the TAC.

Obtaining JWST data

Once observations have been completed and archived, data can be retrieved from MAST via several options. Access restrictions may apply for data within an exclusive access period. See Accessing JWST Data for more information.

Archival research support

As for GO observers, STScI generally provides limited assistance in the reduction and analysis of archived data. Upon request, an Archive Scientist from MAST can work with PIs to identify and guide the development of enhanced data products or software for community distribution via MAST; provide guidance on enhanced meta-data and Digital Object Identifier (DOI) tagging to improve data discovery; and provide assistance with large data volumes and/or multi-mission use of MAST archival data.  The PIs for Treasury or Legacy AR proposals will be automatically contacted by MAST Archive Scientists.  Although an Instrument Scientist is not usually assigned to a funded AR Program, STScI will do so upon request. The Instrument Scientist will serve as a single point of contact to help resolve calibration issues specifically, rather than more general archival support provided by MAST. Proposers should plan to conduct the bulk of their archival research at their home institutions, and should request funds accordingly. Limited resources preclude extensive assistance in the reduction and analysis of data by non-funded archival researchers. 

Failed observations

In Cycle 1, JWST observations failed at a rate of 9.3%. Many of the failures were due to Guide Star acquisition failures and FGS an ACS related anomalies. It is expected tat the failure rate will decrease to a few percent, comparable with HST. Failed observations due to those causes are usually re-scheduled as repeat observations. When this is the case, the proposer receives a notice of the failure and information on obtaining a repeat observation. A smaller fraction of failures do not have a clear cause, and may not be evident from our internal reviews of data quality. Proposers who believe their observation has failed or is seriously degraded can request a repeat observation. The request must be filed within 90 days after the observations are taken and will be reviewed by the JWST Telescope Time Review Board (TTRB). In cases where the failure resulted from proposer error (e.g., incorrect target coordinates), a repeat will not be granted. In cases where the failure was a result of incorrect instrument performance, or incorrect information provided by STScI, a repeat is usually granted. A full description of the TTRB review process is given here.

Publication of JWST results

It is expected that the results of JWST observations and Archival Research will be published in the scientific literature. All refereed publications based on JWST data must carry the following footnote:

“This work is based [in part] on observations made with the NASA/ESA/CSA James Webb Space Telescope. The data were obtained from the Mikulski Archive for Space Telescopes at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-03127 for JWST. These observations are associated with program # ____.”

If the research was supported by a NASA JWST grant managed by STScI, the publication should also carry the following acknowledgment at the end of the text:

“Support for program #____ was provided by NASA through a grant from the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-03127.”

The relevant program ID should be entered in these phrases where indicated. 

Because of the importance of maintaining the accuracy and completeness of the JWST bibliography, a link to an electronic version of each preprint of publications based on JWST research should be sent via email to the following addresses:

  • Chief Institute Librarian, Space Telescope Science Institute, 3700 San Martin Dr., Baltimore, MD 21218, USA (library@stsci.edu)
  • Office of Public Outreach, STScI, 3700 San Martin Drive, Baltimore, MD 21218, USA (scientistnews@stsci.edu)

This requirement includes both refereed and non-refereed publications, but not abstracts or poster papers.

Authors should also include a digital object identifier (DOI) provided by MAST in all papers that use JWST data. This DOI should point to the data analyzed in the paper. It is suggested that authors include the DOI at the end of the "Data" section of the manuscript, e.g.,

"The James Webb Space Telescope data described here can be found at _____"

where the DOI link should be entered where indicated. Including the DOI link will not alter the exclusive access period of the data. MAST provides a service for generating these DOIs, which can be found at http://archive.stsci.edu/access-mast-data/digital-object-identifier-doi.

News release of JWST results

JWST observers have a responsibility to share interesting results of their JWST investigations with the public. STScI’s News branch in the Office of Public Outreach (OPO) is chartered to support NASA in disseminating JWST science and technology information to the general public. In this capacity, OPO offers scientists expert assistance in preparing news releases and the opportunity to share their newsworthy results with hundreds of millions of people. Investigators who believe they have results of public interest should contact the Office of Public Outreach, using the web form http://www.stsci.edu/news/scientist-resources.

Investigators are reminded that NASA maintains the Right of First Refusal for all JWST news releases. Investigators who believe they have newsworthy findings should contact the Space Telescope Science Institute, which produces JWST news releases for NASA distribution, so that their work can be considered for a news release. We encourage the submission of suggestions for news items as soon as scientific results have been submitted for publication, or as an abstract for a science conference. The news submission form can be found here. NASA's policy is to distribute all news fairly and equitably, giving wide access to scientific findings, and enabling a broad impact. OPO works with the scientists’ home institutions to ensure that news items are disseminated nationally as well as locally. The STScI Public Outreach news officers should be made aware of potentially newsworthy science results by principal investigators before the acceptance of JWST publications, with sufficient time for consideration of a news release. 

Visits to STScI 

Most GOs will find that they can analyze their data most efficiently at their home institution, using the JWST Help Desk (http://jwsthelp.stsci.edu) to resolve issues that are not clear from the available documentation. However, observers may find it useful to visit STScI for 2–3 days to learn how to process and analyze their data. Visits can be arranged through the JWST Help Desk. Observers who visit STScI will be assisted by STScI staff to the extent that resources permit.

Next: JWST Grant Funding and Budget Submissions

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