Keck Call & Proposal Instructions

Call for Proposals: UC time on the Keck telescopes

Semester 2025B (Aug. 1, 2025 through Jan 31, 2026)

Deadline: Proposals are due on Thursday, March 20, 2025 by 5:00pm PT

Note: Please be aware of the telescope shutdowns and instrument non-availability (DEIMOS, Keck II-AO, KPIC, etc..)  Read the updates on your favorite instrument below.

1.1 Due Date

Proposals for UC observing time on the Keck Telescopes for Semester 2025B are due by 5:00 pm PDT on Thursday, March 20th, 2025.   There will be 42.8 nights available on K1 and 57.5 nights available on K2 spread evenly across the semester and lunar phase.  The sharp decrease in the number of K1 nights available is due to a shut down from August 31 – October 16 for the second of two planned shutdowns to conduct repairs of the telescope pier. There are 7 one-hour Partnership ToO interrupts available.    A PI may ask for a larger number of UC-time only ToO interrupts as well.

1.2 Proposal Process

This semester UCO is continuing to offer funding for participation in the The Pilina and Kōkua Initiative, a project to facilitate observers from our constituencies to travel to Hawaiʻi, observe at WMKO headquarters, meet and perhaps give informal talks to WMKO staff about science and their scientific program, and most importantly participate in Hawaiʻi community (not necessarily astronomy related) activities. The Pilina (relationship to people and place) and Kōkua (to help in ways that are called for) Initiative will provide travel support for observers for the period of their observations in addition to two extra days to provide time for connection and service to people and place. Participants will spend at least one full day devoted to community engagement programs while at WMKO.   If you wish apply for participation in The Pilina and Kōkua Initiative please indicate this in section 3.5 of your proposal.

The principal consideration in evaluating proposals will be the scientific merit of the proposed project. Projects that take maximum advantage of the unique capabilities of the Keck Telescopes will be given high weight. A brief description should be given of backup programs that will be carried out if conditions are not suitable for the primary program. Please see https://www.ucobservatories.org/observatory/keck-observatory/keck-proposal-instructions/ which describes the UC online proposal submission process, and https://www.ucobservatories.org/observatory/keck-observatory/keck-proposal-guidelines/ which describes the required sections and their page limits. The Time Allocation Committees take page limits very seriously, so please pay close attention as you draft your proposal.

Keck is continuing the login-password system to allow you to retrieve and modify your coversheets. Returning observers should use the same account information as last semester. New observers may request an account from the page http://www2.keck.hawaii.edu/inst/PILogin/login.php

The coversheet form is available through the login page link above. Once you have created a coversheet and you are logged in, please go to the instructions for submitting Keck proposals at: https://spg.ucolick.org/cgi-bin/TAC/login.cgi to create the rest of your proposal as a PDF file to upload to the UC proposal server. Note that the coversheet has been modified again this semester, so please pay close attention when filling it out.

You may use the extra page allocated to the project update if this is a resubmission to respond to the previous TAC comments, even if the previous submission was unsuccessful.  It would be useful to mention the previous proposal title (if different), PI (if different) and proposal number.

1.3 Be Kind to your TAC Members 

Please read the page limits carefully on the keck-guidelines web page (https://www.ucobservatories.org/observatory/keck-observatory/keck-proposal-guidelines/) and adhere to them. TAC members will be instructed to stop reading any text beyond the stated page limits. Note that the text format is 12 point font; single-spaced; one-inch margins.

Although there is not a formal limit on the number of Keck proposals that one PI can submit, experience has shown that TAC members view one PI submitting numerous proposals as a real burden on the reviewing process; it generally does not increase the odds of a PI getting Keck time. Please use moderation.

1.4 Time Domain Astronomy (TDA)

Observers will continue to have the ability to propose both Target of Opportunity (ToO) and Cadence programs using the Keck Cover Sheet. Keck policies related to Target of Opportunity (ToO) and Cadence proposals can be found at https://www2.keck.hawaii.edu/inst/common/Keck_TDA_ToO_policy_SSC_Approved.pdf and https://www2.keck.hawaii.edu/inst/common/Keck_TDA_Cadence_policy_SSC_Approved.pdf.

If your project involves both Classical and TDA observing, you MUST put in two separate cover sheets so that the Keck TDA software can clearly distinguish between the two. Instead of submitting the same text twice, please submit the actual proposal text under the Classical cover sheet; the text submitted under the TDA (ToO or Cadence) cover sheet should merely include the proposal title, PI, and proposal number, together with a sentence stating that the main text can be found under the proposal number of the Classical cover sheet. The Cover Sheet form will not let you submit one proposal requesting both Classical and TDA observing time.

For Semester 2025B, two types of ToO requests can be made.  TAC- approved ToO projects which are able to interrupt observers at any of the four institutions, to increase the utility of the ToO process. These are called Partnership ToO proposals. There is a limit to the number of Partnership ToO interrupts.   The second kind of TAC approved ToO program (Institutional) can only interrupt UC programs.   Note that there is not a limit to the number of “Institutional” ToO interrupts of fellow UC observers. But because UC nights are only a fraction of the total available Keck nights, the probability of a successful ToO interrupt using UC time alone is smaller than for Partnership ToOs. Also note that UC Institutional ToO time can be interrupted by a Partnership ToO, so think through your strategy carefully.   Both Partnership and Institutional ToO interrupts are counted in full 1 hour increments even if less than 1 hour of time is used.  All ToO proposal requests should be made in units of 1 hour interrupts.

In 2025B, partial-night observations can be interrupted. The Keck guidelines state that “Individual TACs may designate a few nights (partial or whole) as exempt from ToO interrupts. This designation must be scientifically motivated, namely that such interruptions would seriously compromise the scientific return of the entire observing time. Proposers should make any such requests to their individual TACs as part of their observing proposal. Use of these exemptions is expected to be rare.” So if you think your project deserves, for scientific reasons, to have one of these rare exemptions from interruptions, please state so in your proposal and give a very strong justification for your request.

1.5 Cadence Observations 

Keck’s policies for Cadence observing (https://www2.keck.hawaii.edu/inst/common/Keck_TDA_Cadence_policy_SSC_Approved.pdf) are reasonably complicated. These include a new category called “Partnership Snapshot” observatories. If you are contemplating applying for Cadence time, please read the guidelines carefully.

Keck continues to reconcile cross-institutional cadence and ToO allocations. Scheduled cadence time is returned to the institution at a one to one rate, and ToO time is returned at a rate of two hours for every one hour interruption because the ToO PI will not choose to call for a trigger if the weather is unacceptable.

1.6  Twilight Cadence Observations

In 2025B, institutions will continue to be able to allocate one twilight observing program per telescope, for a total of up to two programs.  On Keck I, OSIRIS-NGS (imager only) will be available, and on Keck II, NIRC2-NGS will be available.  Please note that due to ongoing AO upgrades, there will be times in the semester when AO is unavailable for cadence observations.  Cadence program PIs are responsible for development of instrument scripts, providing documentation, and training of staff needed to make the cadence program a turnkey operation.

1.7 Large Multi-Year Projects 

UC LMAP observing projects with well-defined scientific objectives that require a large number of nights to bring to completion (normally 10 or more nights per semester). The UC LMAP program allows projects extending for more than one semester to be carried out with multi-year approval from the beginning. LMAPs should generally be directed toward obtaining a high quality, coherent, homogeneous data set that will allow scientific questions of major importance to be addressed in a thorough, systematic manner. Please consult https://www.ucobservatories.org/observatory/keck-observatory/keck-telescope-time-for-lmap-proposals/ for current policies regarding LMAPs.   Please note the additional requirement of inclusion of a Collaboration Management Plan listed at the top of section 1.2.  

A full Collaboration Plan should be submitted to the UCO Director’s office once a proposal has been granted LMAP status, the team must submit a Collaboration Management Plan to the Director’s Office within 2 months. It is not the intent of this policy to require specific terms in CMPs, but  to ensure that collaboration policies are known to members and clearly defined.  The plan should include:

• Publication Policy indicating how authorship and co-authorship is determined/merited.   This should include when this policy will no longer apply, ie. what will the publication policy be once the LMAP data collection is over or proprietary periods have expired.
• How collaboration leadership is structured, e.g. a single PI, committee, rotating spokesperson, etc.
• How membership in the collaboration is determined
• Code of Conduct for the collaboration members and how issues with code of conduct violations will be arbitrated.
• An acknowledgement that the policy has been shared with all members of the collaboration (including early career researchers.)

This plan can mirror or reference other research organization’s plans/codes, e.g. SDSS, AAS, KSM; or can be entirely new.  The Collaboration Management Plan can take as many pages as required, but may be as short as 1-2 pages.   The UCO Director will appoint a group to review the Collaboration Management Plan (CMP) for completeness.  If clarification or changes are recommended by the review committee the LMAP team will have adequate time to respond before the next semester.  The final accepted CMP will be published on the UCO LMAP web pages.

1.8 At-Home (pajama mode) Observing

At-home observing will continue to be available to observers.  Please see https://keckobservatory.atlassian.net/wiki/spaces/MOSD/overview for information about remote observing, including at-home observing.

2.0 Notes on Instruments and Availability 

See the following web page for detailed notes on the availability of instruments for 2025B: https://www2.keck.hawaii.edu/observing/instavail.html.  Please note that the coversheet has been updated with questions about providing KOA data access to observers and Co-Is.  Please contact Cover_Sheet (cover_sheet@keck.hawaii.edu) if you receive any reports of problems with the coversheet form.

SPECIAL NOTES AND CONSIDERATIONS FOR 2025B:

Keck I Telescope:  Keck I telescope will be unavailable for use from August 31 – October 16 for a second planned shutdown to conduct repairs of the telescope pier.

KPF and KPF-CC: The 25B coversheet will contain both the KPF and KPF-CC instrument options.  The KPF Community Cadence (KPF-CC) program is operating a queue observation service in 202B. For PIs who wish to opt in, they must select the KPF-CC instrument on their coversheet. PIs also must submit all proposed observational requests to the queue prior to their TAC’s proposal deadline. Much more detail on the KPF-CC program, how to opt-in, and how to submit requests can be found at this link, please read carefully: https://docs.google.com/document/d/1-TfR6lNEtHO3muw_2Sc7l9Klveb3yovMUu28Jeq21t0/edit?usp=sharing

Keck II AO: Keck II AO (Nirc2 and NIRSPAO) will be unavailable for 3 weeks beginning in mid-August. 

DEIMOS: Deimos will be unavailable from October 1 through the end of January for the installation of a new science detector.

NIRSPAO and KPIC: Nirspao and KPIC will be available through the end of November.  NIRSPAO and KPIC will no longer be available for use once SCALES arrives at the Observatory.  PIs may apply and be scheduled for Nirspao and KPIC time in the December-January timeframe, but must be willing to switch to a backup instrument (Nirspec, Nires, Nirc2-NGS) if SCALES installation is ready to commence during these months.  For more information on SCALES, see https://arxiv.org/pdf/2208.10721

KPIC: KPIC Phase I capabilities continue to be offered as a facility instrument in 25B, during the timeframe that KPIC is available. More information on KPIC Phase I can be found at https://nexsci.caltech.edu/missions/KeckSolicitation/KPIC_PhaseI_Facilitization_Proposal_Instruction.pdf

Instrument Hibernations: WMKO, in consultation with the Science Steering Committee after the receipt of the findings of the Instrument Suite Evolution task force (comprised of members of the WMKO community and WMKO science staff), is undergoing a process of hibernation and eventual decommissioning of instruments in the coming years as new capabilities arrive and to be responsive to pressures on WMKO resources.  A hibernated instrument is not available for community use unless there is a significant emergent scientific and strategic need.  After a year’s hibernation, the hibernated instrument will be completely removed from service and decommissioned.  The community should begin planning for the following:

• NIRES: NIRES will be hibernated at the conclusion of the 2025B semester.
• ESI:  ESI will be hibernated at the end of the 2026A semester.  ESI will continue to be scheduled in campaign mode to limit the number of reconfigs through each semester.
• HIRES: Hires is being considered for hibernation in 2027.  A separate communication soliciting feedback will be sent to the community.
• Additional instruments are under consideration for hibernation and eventual decommissioning in later semesters, with a focus on those instruments whose capabilities are being significantly superseded by new instrumentation.

NIRSPEC/NIRSPAO reconfigs:  Please note that Nirspec and Nirspao/KPIC nights will be scheduled in campaign mode to limit the number of reconfigs into AO during the semester.  This may impact the ability to schedule certain date critical observations.

Notes regarding Subaru facility and instrument availability in 25B:

 Note that PIs must contact the instrument PI for visiting instruments in advance.  Subaru may support half night allocations, but whole night allocations are preferred.   Queue observing is the default observing mode for HSC, applicants who desire classical mode must justify their request. Please check the HSC queue mode website https://www.naoj.org/Observing/queue/index.html for more details.

• Telescope Downtime: There is a possibility of three(3) weeks of downtime after October for repairs to the dome’s main shutter.
• NsIR Downtime: All instruments except for IRD on the NsIR focus – including IRCS, SCExAO(CHARIS, VAMPIRES, FastPDI), and REACH – will be unavailable for about 2-3 months from August. After the installation, all IRCS, SCExAO, and REACH observations will be done with the NBS under shared-risk mode. Please see the IRCS and SCExAO webpage(s) for the possible impacts of the NBS.
• SSP: In S25B, PFS-SSP will be assigned about ~10-20 nights over ~3-4 observing runs. IRD-SSP is expected to be completed in S25A.
• LGS-AO with TBAD: The laser guide star (LGS) system for AO188 will be operated with TBAD (Transponder Based Aircraft Detector) under shared-risk mode.
• AO upgrade: As part of the AO3k project, the DM has been upgraded from a 188-element bimorph mirror to a 3228-actuator magnetic mirror. AO188 provides three modes: NGS-AO188 mode (uses 188-element WFS + 3k-element DM), LGS-AO188 mode (uses 188-element WFS + 3k-element DM), and NIRWFS-AO3k mode (uses NIR WFS + 3k-element DM). While NIR WFS provides high-performance AO correction, NGS and LGS mode performance is unchanged because they use 188-element WFS. Please refer to the AO188 webpage(s) for more information.
• Rule for queue/classical mode: HSC/PFS Queue-mode programs should consider 30% bad weather factor in order to increase the overall observation completion rate. Accordingly, the requested time for HSC/PFS Queue-mode proposals should not exceed 3.5 nights. It is possible to request up to 5.0 nights in the case of Classical requests.
• Available facility instruments: Adaptive Optics (AO188-mode/AO3k-mode), FOCAS, HDS, HSC, IRCS, MOIRCS, PFS.
• Available PI-type instruments/devices: CHARIS, FastPDI, IRD, MEC, REACH, SCExAO, VAMPIRES, NsIR-WPU, NIR-WFS.  Proposals using the visiting instruments/devices must include the relevant PIs as Co-investigators.