The NRAO and the Space Telescope Science Institute (STScl) are entering into an agreement to support joint proposals with NRAO/GBO telescopes (VLA, VLBA, and GBT) and the James Webb Space Telescope (JWST).

Joint observing proposals will be available starting with NRAO semester 24B (proposal deadline 31 January 2024, with observations commencing in October 2024) and with JWST Cycle 3 (proposal deadline October 2023, with observations commencing in July 2024). Joint proposals will be permitted for the main call for JWST and both semester calls for the NRAO.

NRAO as Main Observatory

The NRAO will be able to award up to 50 hours of JWST time per cycle to highly rated proposals.

Joint proposals requesting JWST time may request standard JWST observing modes. Establishing the technical feasibility of the JWST observations is the responsibility of the PI, who should carefully review the JWST Call for Proposals, JWST Documentation, and/or contact the JWST Helpdesk at jwsthelp.stsci.edu. The JWST Helpdesk offers features to search the documentation and to send your question directly to the appropriate team of experts.

For proposals that are approved by the NRAO, STScI will perform final detailed feasibility checks. STScI reserves the right to reject any NRAO-approved Joint Proposal observation that proves infeasible, impossible to schedule, dangerous to the JWST instruments, and/or requires resources beyond those initially approved. Any JWST observations that prove infeasible or impossible could jeopardize the overall science program and may cause revocation of the corresponding NRAO/GBO observations. Duplicate JWST observations may also be rejected by the STScI.

Regarding Joint Target of Opportunity (ToO) proposals, no more than one (1) disruptive JWST ToO of the joint program will be performed per JWST Cycle (reaction time 14 days or less). Furthermore, Ultra-rapid JWST ToO requests (reaction time 2 days or less) will not be accepted for this program; proposals asking for Ultra-rapid JWST ToO observations must be submitted in response to the JWST Call for Proposals, with JWST as the primary observatory. It is mandatory that the PI informs both observatories immediately if the trigger criterion is fulfilled.

STScI will contact successful PIs of joint programs. US-based Investigators of NRAO-JWST Programs are eligible for funding and will be eligible to submit budgets to JWST Grants.

NRAO proposals requesting JWST time must provide the following technical justification in addition to the scientific justification which must formally state why JWST observations are necessary to complete the science goals of the proposal:

•  A determination of the total duration of the proposed JWST observations, including overheads. This can only be determined using the JWST Astronomer's Proposal Tool (APT).

• Quantitative estimates of the accuracy required (e.g. exposure times or expected RMS) to achieve key science goals. The JWST Exposure Time Calculator (ETC) generally provides sufficient information to determine the necessary exposure time.

• Selection of instruments, modes, filters, gratings, and any additional constraints. Justification for the instrumentation MUST be included in the submitted science case.

• Special Observational Requirements (if any): Justify any special scheduling requirements on timing or orientation, including time-critical and target of opportunity (ToO) observations.

• Coordinated Parallels (if any): Justify any coordinated parallel observations (meaning using multiple JWST observing modes at the time, where one of the JWST modes is considered “prime”). It should be clearly indicated whether the JWST parallel observations (i.e. those that are “not prime”) are essential to the interpretation of the science program as a whole, or whether they address partly or completely unrelated issues.

• Justification of Duplications (if any): as detailed in the JWST Duplicate Observations Policy, any duplicate observations must be explicitly justified.

• Target of Opportunity (ToO) proposals (if any): ToO proposals should estimate the probability of occurrence during Cycle 3, specify whether Carry-Over status is requested, must state explicitly whether the JWST observations require a disruptive ToO (observations within 14 days of notification), and state clearly how soon JWST must begin observing after the formal activation.

Proposers must fill out APT templates for each of their requested JWST observations to make sure that they are feasible. Proposers will be submitting this APT file and a PDF attachment to STScI after the NRAO deadline. This will also allow the observer to account for observatory and instrument overheads in their time request. The observations may also be visualized in Aladin to verify target coverage and any issues with bright stars or extended emission in the field of view.

Staff from STScI will contact the PIs of submitted Joint NRAO-JWST programs requesting the APT file and PDF attachment which must be submitted to STScI no later than 4 weeks after the NRAO proposal deadline has passed. This step is required for all submitted joint proposals. This is to allow STScI staff to conduct a technical review that assesses the feasibility of the observations and their total duration (so the NRAO TAC knows how much JWST time is allocating). The requested JWST observations will be held to the same technical standards as they are for all GO JWST proposals. The information is as follows:

• The APT file with a full description of the observations. The proposal must have the same Title and Abstract as in the NRAO proposal, adding the NRAO ID to the Abstract so it can be matched to the NRAO program. Proposers should make sure that they the mark the APT coversheet using the menu that expand out corresponding to "Coordinated telescopes", providing all the requested information.

• A PDF attachment should be provided using the template available here.

JWST as Main Observatory