NICER Proposals and Tools: Cycle 6

GO Cycle 6 Proposal Selection Announcement

Posted: 20 November 2023

The NICER mission is pleased to announce that the proposal selection process for GO Cycle 6 is complete, and observations will begin March 1, 2024. Documents listing selected proposals and approved targets have been released.

Target of Opportunity targets requested by more than one proposal have been prioritized according to feedback received from the review panels. If you feel a target has satisfied the trigger criteria, contact the NICER science team as soon as possible via the NICER Target of Opportunity/Director's Discretionary Time Request form. Be sure to include your accepted proposal number in the scientific justification.

U.S. principal investigators will be notified directly regarding invitations to submit Phase 2 budget proposals. Phase 2 proposals are submitted to NASA's NSPIRES system. In addition, there are reporting requirements for proposals with budget awards. The deadline for submission of Phase 2 proposals is January 24, 2024 at 4:30pm ET.

NICER Guest Observer Program: Cycle 6

In 2018, NICER began to solicit Guest Observer proposals from the general scientific community via NASA's ROSES Research Opportunities. A Phase 1 (Science) proposal is submitted to NASA HEASARC's ARK/RPS system, containing detailed target selection forms and a concise science justification. Proposals may come from both US and non-US researchers. Phase 1 proposals are evaluated by peer review panels. Data from approved GO observations are public by default, however, GO proposal PIs can request a six month exclusive-use period, subject to peer review approval.

NASA also provides grant funding to support certain selected proposals. These funds are limited to proposals with PIs at US institutions. Selected proposals will receive a notification letter with more details and an invitation to submit a Phase 2 (Budget) proposal. Phase 2 proposals are submitted to NASA's NSPIRES system. In addition, there are reporting requirements for proposals with budget awards.

Date Important NICER GO Cycle 6 Events
February 14, 2023 Release of NICER Guest Observer Cycle 6 Announcement
June 7, 2023 Cycle 6 Phase 1 Proposal Submissions Open
September 14, 2023 Cycle 6 Phase 1 Proposals Due - 4:30pm ET
November, 2023 Cycle 6 Peer Review
January 24, 2024Phase 2 Budget Proposals Due - 4:30pm ET
March 1, 2024 Cycle 6 Observations Begin

Notable in Cycle 6:

  • Starting in Cycle 6, proposals are allowed a maximum length of 6 pages (4 pages for the science justification, 1 extra page to discuss joint programs, and one page for references). Proposals that do not request joint observing time are limited to 5 pages.
  • Starting in Cycle 4, all Phase-1 proposals submitted to the NICER Guest Observer Program are evaluated following a dual-anonymous peer review process. See NASA's Dual-Anonymous Peer Review page for details.

General Information

NICER Guide for Proposers

The Guide for Proposers summarizes guidelines from the NASA Research Announcement for NICER Guest Observers. It also describes in detail the elements and submission method for Phase 1 (Science) NICER Guest Observer proposals, as well as for Phase 2 (Budget) proposals.

NICER Phase 1 (Science) Proposal Submission

The HEASARC's Remote Proposal System (RPS) is an automated service providing Guest Observers from around the world an easy-to-use facility for submitting proposals in response to NASA Research Announcements.

NICER Joint Programs

Starting in Cycle 5, NICER users can propose to observed on other NASA facilities in support of their proposed NICER observations. The NICER mission has established joint observing programs with NASA's Nuclear Spectroscopic Telescope Array (NuSTAR), the Neil Gehrels Swift observatory (Swift), and the Transiting Exoplanet Survey Satellite (TESS). Proposals requesting joint observations must clearly justify the need for the NuSTAR/Swift/TESS observations in order to accomplish the science goals of the proposed NICER investigation. Please see the NICER Joint Program document for details.

NICER Proposal Tools

The NICER Proposal Tools provide documentation of the mission and applications/files that can be used for count rate and spectral simulations in order to help potential proposers demonstrate the feasibility of their proposed NICER observations. Approximate target visibility windows can be determined and NICER-specific observation properties are described.

  • Background Estimation: Three tools for estimating NICER's background for an observation were released in NICERDAS 10 (released with HEASoft 6.31). The tools are: niscorpeon, nibackgen3c50, and nispaceweather.
  • See the Analysis Page and the NICER Science Analysis Threads regarding NICER analysis issues.
  • See the NICER Analysis Threads for detailed information on analysis of NICER data
  • Target Planning: Proposers can use the HEASARC Viewing tool for long term planning. Please not that the viewing tool only includes Sun angle and moon angle avoidance constraints. NICER target visibilities are also constrained by the orientation of the ISS in its orbit, but which is not predictable beyond about 2 weeks (or less) from the current date. The NICER Enhanced Visibility calculator includes ISS orientation and orbit information for determining near term target visibilities for times within about two weeks from the current date.

Additional Opportunities to Propose for NICER Observing Time

Unsolicited NICER Target of Opportunity (ToO) or Director's Discretionary Time (DDT) Observations

The Cycle 6 GO program allows for ToO proposals to observe both known and unknown sources. In addition, unsolicited ToO requests for transient and unpredictable phenomena, from both known and previously unknown sources, can be made using the the NICER ToO request form. (Please review the NICER ToO Policy before making your request.)

Joint Programs Through Other Observatories

Currently NICER has arrangements with the NuSTAR observatory which makes available joint observing time. Please see the NuSTAR Proposal page for more information about the current NuSTAR Announcement of Opportunity.

NICER News & Helpdesk

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