NICER Proposals and Tools

GO Cycle 4 Proposal Selection Announcement

Posted: 23 February 2022

The NICER mission is pleased to announce that the proposal selection process for GO Cycle 4 is complete, and observations will begin March 1, 2022. 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.

Please note:

  • Observations after Sept. 30, 2022 are contingent on Senior Review mission continuation.
  • The deadline for Cycle 5 proposals (September 7, 2022) is earlier than for previous cycles.

NICER Guest Observer Program: Cycle 4

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 4 Events
February 21, 2021 NICER Guest Observer Cycle 4 Announcement
August 12, 2021 Cycle 4 Phase 1 Proposal Submissions Open
November 10, 2021 Cycle 4 Phase 1 Proposals Due - 4:30pm ET
January 2022 Cycle 4 Peer Review
March 1, 2022 Cycle 4 Observations Begin

Notable in Cycle 4:

  • As in Cycle 3, 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.
  • Clarification of language describing multi-year investigations and requests for joint NuSTAR time.

General Information

NICER Cycle 4 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 Cycle 4 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 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.

Additional Opportunities to Propose for NICER Observing Time

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

The Cycle 4 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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