Fermi Gamma-ray Space Telescope

Fermi-NOIRLab Cooperative Arrangement


In recognition of the importance of optical observations enabled by the National Optical-Infrared Astronomy Research Laboratory (NOIRLab) to the scientific exploration by the Gamma-ray Large Area Space Telescope (Fermi), the Fermi-NOIRLab cooperative arrangement commits observing time on NOIRLab telescopes for coordinated observations of Fermi-relevant sources, on a competitive peer-reviewed basis. The scientific investigations that will be supported within this program are those that are enhanced by the combination of Fermi observations with investigations using the optical facilities operated by NOIRLab and/or those nominally accessed via the NOIRLab Time Allocation Committee process. Some examples are given below. The philosophy of the approach, in keeping with the missions of both Fermi and NOIRLab, will be that of maximum data availability and maximum scientific return for the entire user community. This agreement is similar in scope and intent to existing agreements between Fermi and other organizations (e.g., NRAO) and between NOIRLab and other observatories (e.g. the Hubble Space Telescope, the Spitzer Space Telescope, and the Chandra X-ray Observatory).

Background Description of NOIRLab Telescopes

NOIRLab's mission is to provide to the community merit-based access to state-of-the-art optical and near IR observational capabilities over a full range of telescope apertures for the purposes of carrying out forefront research and educational activities. NOIRLab is operated by Associated Universities for Research in Astronomy, Inc., under a cooperative agreement with the National Science Foundation. NOIRLab operates Kitt Peak National Observatory near Tucson, Arizona, on land leased from the Tohono O'odham Nation, and Cerro Tololo Inter-American Observatory near La Serena, Chile. The NOIRLab Gemini Science Center, part of NOIRLab, provides researchers access to the two 8-m telescopes of the Gemini Observatory, located in Hawaii and Chile. NOIRLab also provides limited access to other leading ground based observatories via the NOIRLab Time Allocation Committee (TAC) process. These facilities include the W. M. Keck Observatory, the Hobby-Eberly Telescope (HET), the MMT (6.5-m telescope), and the Magellan (twin 6.5-m telescopes).

Collaborative Proposal Process within Fermi GI Program

The collaborative proposal process will be implemented via the normal Fermi GI Program. Note that regular proposals to NOIRLab are evaluated every six months (proposal deadlines the end of March and September), whereas the Fermi GI Cycle will be annual. There are two distinct types of collaborative observations and funding opportunities between NOIRLab and Fermi that will be implemented through the Fermi GI program. To distinguish these two opportunities, we call them the "Joint Proposal Opportunity" and the "Cooperative Proposal Opportunity," respectively. The two opportunities are described in turn below.

Joint Proposal Opportunity

This Fermi/NOIRLab opportunity is a Joint Proposal Opportunity, whereby potential optical, near-IR, and mid-IR observers submit proposals for Fermi funding and future NOIRLab observations through the Fermi GI portal. A range of telescope time (see below) will be made available by NOIRLab for the Fermi GI program. It is anticipated that the list of available facilities will be revised prior to each Fermi call for proposals. Changes will be made as required to respond to changes in the availability of telescopes/instruments and on-going evaluation of the utility of various capabilities to contribute significantly to the science mission of Fermi. In turn, Fermi/NASA will make data-analysis funding available to successful U.S.-based investigators requesting NOIRLab observing time through the GI process. These proposals will make use of Fermi survey data products, while those for succeeding cycles may also include both NOIRLab and Fermi pointed observations. The peer-reviewed GI proposal-evaluation process will identify programs with sufficient science justification to be allocated funding by Fermi, and those that fall within the agreed-on range of available NOIRLab observing time and pass the nominal NOIRLab technical review (feasibility and schedulability) will be allocated NOIRLab observing time and Fermi funding without additional scientific review.

Proposals for NOIRLab observing time submitted through the Fermi GI program will be successful only if the proposed ground based observations are necessary for the realization or significant enhancement of the proposed science program. Examples of science topics that will directly benefit from joint observations include:

  • Long-term photometric monitoring on selected Fermi objects to understand optical variability in the gamma-ray quiescent state.
  • Counterpart candidate studies, including redshift determination of previously unknown BL Lacs and high-redshift blazars.

This list is intended to illustrate the kinds of opportunities enabled joint program and it is not exclusive. Proposals for other Fermi-NOIRLab investigations are also welcome.

The following telescopes and associated instruments are available for time allocations at the stated levels of observing time via proposals to the Fermi request for proposals. [Note that Target of Opportunity Proposals cannot be submitted via this process, but can be submitted via the "Cooperative Proposal Opportunity" described in following section] Prospective proposers should check the NOIRLab website and/or contact their helpdesk to ensure that the desired telescope/instrumentation will be available during the required timeframe, i.e. during the Fermi GI cycle in consideration.

  • CTIO Blanco 4-m telescope (5%; approximately 15-18 nights a year)
  • SOAR 4.2-m telescope (1.5%; this is 5% of the 30% share of time NOIRLab has on this telescope)
  • KPNO Mayall 4-m telescope (5%; approximately 15-18 nights a year)
  • WIYN 3.5-m telescope (2.0%; this is 5% of the 40% share of time NOIRLab has on this telescope)
  • KPNO 2.1-m telescope (5%, with perhaps up to 15% depending on the collective proposal pressure for this telescope; approximately 15-50 nights a year)
  • WIYN 0.9-m telescope (up to 5%, approximately 15-18 nights a year; via NOIRLab time on this telescope; note that this will generally not include the use of the MOSAIC-1 imager with this telescope, as very little time is available for NOIRLab users on the WIYN 0.9m using this instrument, and requests for MOSAIC-1 on WIYN 0.9m via the Fermi GI program will be scheduled on a best effort basis)
  • Gemini-North and Gemini-South (5% of NOIRLab time, which is approximately 40 to 45% of the nights, exact number depending on engineering and commissioning schedule; note that recommended programs will have to submit the NOIRLab proposal form to aid the NOIRLab TAC assign Fermi-recommended observations to priority bands in the Gemini queue program).
  • SMARTS (5% of NOIRLab time, or 60 hours/year, and <1 hour on any one night, on each of the four telescopes. See https://noirlab.edu/science/programs/ctio/telescopes/smarts-consortium)

Because the exact number of nights available for scheduling on a given telescope varies each semester (due to variable needs for engineering/maintenance of the facilities), the exact number of available nights will not be known at the time proposals are submitted. Time reserved for proposals submitted under the process set up by this arrangement will be expressed as percentages of the scheduled science observing time available for a given telescope. The numbers of nights listed above are representative of the numbers of nights available for the past few years and are a guide to the anticipated total number of nights available in the future. The various telescopes/facilities are currently scheduled predominantly in what is called "classical mode", i.e. proposers are assigned specific nights (or fractions of nights), although some queue or service observing telescopes are in the system of telescopes that might become available to Fermi proposals during the lifetime of this arrangement. For the purpose of proposals, we shall consider each night of telescope time as consisting of 9 hours of possible observations, while the exact amount of time available is a function of many variables. Available time will be distributed over RA range and sky brightness conditions (dark and bright time). Time requests via the Fermi GI proposal process may specify hours instead of nights, but NOIRLab generally schedules observing time in full night increments.

The proprietary nature of the optical data will follow the standard NOIRLab policies. Investigators using facilities accessed via NOIRLab nominally have an 18-month proprietary period. All users of data obtained from NOIRLab or other NSF funded facilities should use the appropriate acknowledgement (see the section below, and the NOIRLab web pages for updates of this wording).

The actual amount of NOIRLab observing time allocated via the Joint Fermi Process will depend on the amount of proposal pressure and the scientific quality of the proposals. If there are very strong scientific proposals for more time, and the Fermi mission has funds available to support data analysis, the Fermi Project Scientist will request additional time from the NOIRLab Director, who will set up an NOIRLab mechanism to evaluate and respond to this request. This might enable additional programs to be supported in such an over-subscribed cycle, but more probably will lead to an adjustment in possible time allocations for future cycles.

We recognize the possibility that accepted regular NOIRLab proposals may include observations that have some overlap with observations approved in the Fermi GI cycle. NOIRLab and the Fermi mission will resolve such duplications on a case-by-case basis in an effort to avoid excessive duplication, but scheduling multiple teams for similar/identical observing programs is not excluded.

Cooperative Proposal Opportunity

Direct proposals for NOIRLab observing time that will enhance the scientific return associated with the Fermi mission may also be eligible for NASA funding through the GI program. Interested proposers will need to submit proposals, by the appropriate deadlines, to both the Fermi GI program and NOIRLab. These proposals will be of two NOIRLab types - Survey Program proposals (requesting large amounts of telescope time, see the NOIRLab survey pages for description: https://noirlab.edu/science/observing-noirlab/proposals/surveys) and Target of Opportunity proposals, which respond to time-critical transient events. NOIRLab typically accepts and evaluates Survey Program proposals once a year. Target of Opportunity proposals are accepted during the regular NOIRLab proposal calls (these are anticipatory in nature, outlining the science that would be done with observations that would be requested when certain conditions or triggering event takes place) or in exceptional cases at any time. These two types of proposals are distinguished from the proposals in 'Joint Proposal Opportunity' (described above) because they will involve requests for Fermi GI funding subsequent to NOIRLab approval of observing time. Proposers of NOIRLab observations who also intend to propose for Fermi funding via this process must indicate their intentions clearly in the NOIRLab proposal, and all information related to the NOIRLab review of successful proposals will be forwarded to the Fermi mission for their evaluation. Note that the award of observing time will not be a guarantee of Fermi funding. Likewise, the observing time is not contingent on Fermi funding in this case.

See https://noirlab.edu/science/observing-noirlab/proposals/surveys for further descriptions of the NOIRLab Survey and Target of Opportunity proposals.

Scheduling of NOIRLab Observing Time and Award of Research Funding by NASA

The recommendations for observing time made as a result of the proposal processes outlined above will be scheduled on a best effort basis by the observatories. In general the majority of recommended programs will be scheduled, but practical constraints (availability of instruments, etc.) might occasionally prevent the scheduling of an otherwise meritorious and well ranked proposal. Further, if weather prevents a program for obtaining data, NOIRLab does not generally reschedule such programs unless the program is again recommended by a TAC. Similarly, most technical problems will not result in a program being given additional observing time. Programs that suffer from major failures (e.g., loss of an entire observing run due to technical difficulties) are sometimes rescheduled. Such decisions are made on a case-by-case basis by the respective observatory director.

In a similar manner, a program recommended for funding by NASA as a result of one of the two proposal processes outlined above is not guaranteed to receive funding. Such decisions follow the guidelines outlined by NASA and the Fermi mission.

Credits and Attributions

For results obtained using Fermi and NOIRLab facilities, proper attribution to NOIRLab facilities must be included in all publications, conference proceedings, posters, abstracts and talks and colloquia, as in the following: "This work is based [in part] on data obtained using the (appropriate telescopes) at (appropriate facility) of NOIRLab, which is operated by AURA, Inc., under a cooperative agreement with the National Science Foundation." Proper attributions to NOIRLab facilities must also be included in all NASA press releases and press conferences. Fermi attribution will be the same as for all other use of Fermi data products.