Call for Proposals

Proposals Due:

Allocation Announcements Expected Approximately

1.0 Telescopes & Period

  • Keck I and Keck II, with possible trades for SUBARU time.
  • Palomar Hale/200-inch.
  • Observing Semester : inclusive.

2.0 Eligibility

Summary: Caltech Faculty, Senior Research Associates, Senior Research Fellows, Post-Doctoral Scholars, Senior Research Staff (approved by the COO Director) and Graduate Students may apply for COO-administered observing time at Keck and Palomar, subject to the following:

  • Applicants must be in residence at Caltech at the time proposals are submitted and throughout the subsequent academic quarter (i.e. fall quarter inclusive for A semester/fall-submitted observing proposals).
  • Caltech Faculty and Senior Research Associates may submit no more than three Keck proposals and/or any number of Palomar proposals.
  • Caltech Senior Research Fellows, Post-Doctoral Scholars and Senior Research Staff may submit any number of Palomar proposals but are limited to one Keck proposal per semester.
  • Caltech Graduate Students may apply for Palomar time only.

3.0 Proposals

Summary: Proposals are prepared using provided template documents and telescope-specific cover sheet forms, rendered into PDF, and submitted in email as described in the following sub-sections.

3.1 Proposal Package Outline

  • Each proposal should cover a single, coherent, well-defined scientific topic.
  • Proposals consist of three components: Cover sheet (section 3.2), Discussion (including Scientific Justification, Technical Justification, and Supplementary Information; section 3.3), Observing List (if available in advance, e.g. not relevant for TOO/transient programs; section 3.4). All proposals shall include these components, and may also include additional components (e.g. Date-Specific Supplement) as appropriate.
  • A report of your observing history and bibliography (section 4.0) is a required adjunct to your submitted proposal set.
  • If you submit two or more Keck proposals, the one representing your highest-priority shall be designated as Primary; all others are Secondary. Similarly, if you submit two or more proposals for the Palomar telescopes, your highest priority Palomar project shall be designated as Primary; all others are Secondary.
  • All Caltech-COO telescope time proposals shall follow the proposal template available in either MS Word, Google doc, or LaTeX form (see also the supporting latexdefs.tex package).
  • P200 Large Project proposals may not be combined with Keck proposals, but must instead be separate, distinct proposal package submissions. Please see the updated Palomar Large Project Proposals policy.
  • TOO proposers with previous TOO allocations must include a report on allocated and activated TOO triggers over the previous two semesters in new TOO observing proposals. Please see (section 2.7 in) the MS Word, Google doc, and LaTeX proposal template forms.

3.2 Cover Sheets

  • Keck: Log into your Keck account at the Keck Observer Login Page. Fill in the required information, particularly including the project abstract. For guidance regarding the selection of acceptable runs, see section 3.2.1 below.
  • Palomar: Log into the appropriate Palomar cover sheet (see links at left) and fill in the required information, particularly including the project abstract.

3.2.1 Run Table Entries

Both Keck and Palomar cover sheets use a run table and a system of P's and A's to designate project preferred and acceptable runs respectively. Proposers shall fill-in the run table, entering P and A designations for each proposed observing block — one row in the observing table for each separate observing program block in the semester. The telescope scheduler will will typically only assign observing time in a run that has been designated by the proposer as P or A. Proposers are strongly recommended to be as flexible/generous as possible in designating acceptable runs; highly-restrictive acceptable selections make telescope scheduling difficult and, in extreme cases, may even preclude the assignment of observing time to the project.

Putting all the P's and A's on a single line means you want the time scheduled in a single block, if possible. If you want the time distributed into two or more blocks, use a separate line for each block.

3.3 Proposal Discussion & Figures

Using one of the MS Word, Google doc, or LaTeX proposal templates, provide a concise (see page limits, below) description of the project, explaining the scientific goals and methodology, and justifying the observing time and equipment requested in the present semester. Project abstracts are included on the corresponding cover sheet (section 3.2), so it is viable to omit repeating the abstract in the discussion section. Include citations to publications referenced in the discussion. New project proposals shall present an estimate of the total observing time required to complete the project; continuing project proposals shall summarize the status of previously obtained data and an updated estimate of the observing time needed to complete the project. The proposal template is structured to facilitate proposals responsive to these requirements; please fill out the template following (and replacing) the embedded instructions.

Page Limits
DescriptionDiscussion & Figures
General Proposals (both Primary and Secondary) 5.5 pages plus observing list
Palomar - Large Project 8 pages plus observing list
Definition: 1 page = One side of a sheet 8½ × 11 inches, with suitable margins. Type size = 11- or 12-point.

3.4 Observing List

Provide a list of targets to be observed, including names, coordinates (in sexagesimal format: RA in hh:mm:ss, Dec in dd:mm:ss) and apparent magnitudes. Observing lists are excluded when assessing proposal compliance with page limit restrictions.

3.5 Proposal Package Submission

When finished, combine your cover sheet, discussion and observing list into a single consolidated PDF document (see section 5 below) and attach it to an e-mail to brucato-[at] not later than . As it eases processing the last-minute proposal rush we welcome and encourage early proposal submissions.

If you do not receive confirmation of your proposal submission within 48 hours, contact brucato-[at] immediately.

4.0 Observing History and Bibliography

Summary: All applicants shall submit an observing history and bibliography report supporting proposal submissions.

The COO Director places a premium on the demonstrated effective use of telescope time and timely publication of results derived from observations. Accordingly, all proposers are required to submit an observing history and bibliography report as a separate submission/document, distinct from any submitted proposal packages.

Your observing history and bibliography report shall consist of:

Observing History: List the observing time allocated to you for all projects in the last four semesters [ inclusive] and summarize the status of each. Provide:
  1. Semester.
  2. Telescope and proposal number.
  3. Instrument(s) used.
  4. Number of nights allocated and the number of nights usable.
This report is important for all proposers, but particularly so for applicants who are requesting continuations of projects previously awarded time by the Caltech TAC.

Bibliography: Provide a bibliography of your refereed papers based on Keck (or from observing time awarded through Keck trades) and/or Palomar data, published or submitted for publication during the last four semesters [ inclusive], even if you were not the principal investigator of the observing proposal(s).

Submit (a PDF rendering of) the observing history/bibliography report in separate e-mail (i.e. not integrated with a proposal) to brucato-[at] by the proposal due date ( ).

5.0 Informational Notes

Summary: This section contains a collection of specific, informational notes relevant to Caltech proposers to Keck and Palomar.

Date-Specific Observing

Date-Specific observing is restricted to projects requiring observations at particular times (e.g., occultations, transits, critical phase coverage in a binary, etc.). Proposers requesting date-specific observations must check the Date-Specific box on the proposal cover sheet, and justify the date specificity (i.e. see proposal template section 2.5). For Palomar, load the Date-Specific Cover Sheet Supplement, fill in the required information and include it in your proposal as an addendum to the appropriate cover sheet/proposal package.

5.1 Special Notes - Keck

  1. Only a single proposal is needed for a project involving both Keck I and Keck II.
  2. By November 2018 Keck SSC/CARA Board/WMKO Director action there are governing policies in place for Time-Domain Astronomy (TDA). Please find current Keck policies at the WMKO Cadence & TOO Policy webpage.
  3. Partial nights (¾, ½, ¼) may be requested at Keck, however project advocates should be mindful that it is more difficult (and may not always be possible) to schedule partial night allocations.
  4. Following 5.1.2 above there are now five observing modes at Keck relevant for Caltech proposers:
    1. "Classical" observing.
    2. Caltech Internal ToO - Target of Opportunity interrupts of Caltech observer (see Caltech TOO page). This is the default ToO request status unless otherwise specified by the proposer [ToO proposers should refer to the proposal template section 2.6].
    3. Partnership ToO - Target of Opportunity interrupts of all Keck partners. See Partnership ToO Policy. Proposers for Keck Partnership ToOs must specify their requested number of Partnership ToOs clearly in their proposal in the proposal template section 2.6. [Please note the maximum number of Partnership ToO interrupts available to Caltech is seven (7) per semester.]
    4. Cadenced observing. See Cadence Policy.
    5. Date-specific observing.
  5. For projects involving both Keck and standard Palomar requests, submit the Keck and Palomar cover sheets separately. The discussion and observing list need be attached only to the Keck cover sheet. Please note that P200 Large Project proposals may not be combined with Keck proposals, but must instead be separate, distinct proposal package submissions. Please see the updated Hale Telescope Large Project policy.
  6. Applicants for Keck Target of Opportunity (ToO) observations shall report on the status of any previous ToO allocations at either Keck or Palomar. See proposal template section 2.7.
  7. There are typically Keck telescope infrastructure and instrument-specific status notes for semester . Proposers are strongly encouraged to consult the Keck Instrument Availability webpage for authoritative status information.
  8. Subaru exchange: The Subaru-Keck exchange will continue as previous semesters with flexibility as to the number of nights available for exchange. The final number will be determined based on the demand from each community. Please see the Keck Instrument Availability webpage for pertinent Subaru instrument information in semester .
  9. Astronomer Community Engagement (ACE) Program: Directors at Caltech Optical Observatories, University of California Observatories, and the W.M Keck Observatory have identified an acute need for astronomers from the mainland to meet WMKO staff and members of the Hawaiʻi community, to further bilateral understanding of the issues at stake surrounding observatories on Maunakea. Further there is critical need for astronomers to demonstrate a willingness to give back to and foster a reciprocal relationship with members of the Hawaiʻi community.

    Therefore, the COO, UCO, and WMKO Directors are jointly initiating a pilot Astronomer Community Engagement (ACE) program to encourage observers from our constituencies to travel to Hawai’i, 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 engagement activities. This program will provide travel support for one observer for the period of their observations in addition to two extra days to provide time for these additional activities. Program participants will spend at least one full day devoted to community engagement programs while at WMKO. Additional details on the ACE program are available at ACE Program page.

    Proposers should indicate in the proposal template (section 3.5) their willingness to participate in the ACE program. Based on the response, and the observation scheduling, COO will coordinate with WMKO to accommodate approximately six observers per year, three per semester, for the engagement program from within the Caltech constituency. UCO will do likewise from among the UC constituency. Expressions of interest will not impact TAC grades or time allocations.

5.2 Special Notes - Palomar

  1. Proposers may request full or half nights on Hale/P200. Project advocates should be mindful that it is more difficult (and may not always be possible) to schedule partial night allocations.
  2. For Hale Telescope instruments, see Palomar Observer Information. Private and Semi-private instruments may be requested only with prior approval of the instrument builder. Please include in the discussion a confirmation that appropriate arrangements have been made.
  3. The Hale Telescope facility Double Spectrograph (DBSP) will remain in service throughout 2024A. We anticipate DBSP will be decomissioned/repurposed to support NGPS integration during the 2024B semester, contingent on NGPS readiness (see next).
  4. The Next Generation Palomar Spectrograph (NGPS) will enter it's initial r and i channel commissioning phase in 2024A. Opportunities for early/commissioning/shared-risk science may emerge over the course of the semester. Expressions of interest in possible early science opportunities with NGPS will be solicited separately.
  5. Most P200/Hale Telescope instruments may be used in remote observing mode. For additional information, see P200 Observer Information.
  6. At the 200-inch telescope, proposers may request instruments to be installed simultaneously at the prime focus and Cassegrain focus but project advocates must justify the request in the proposal. Secondary instruments should be requested only if they are integral to the project and if there is a high probability that they will be used during requested observing runs.
  7. Applicants for Palomar Target of Opportunity (ToO) observations shall report on the status of any previous ToO allocations at either Keck or Palomar. See the proposal template section 2.7.
  8. Proposals for 200-inch time in support of Large Projects may be submitted. See Hale/P200 Telescope Large Project Policy for details. Please note that P200 Large Project proposals may not be combined with Keck proposals, but must instead be separate, distinct proposal submissions.
  9. Palomar 60-inch Telescope - Proposal solicitation for P60 observing time is deferred to a supplementary call to be announced later.
  10. Oschin (P48) Telescope - Proposal solicitation for P48 observing time is deferred to a supplementary call to be announced later.

Merging PDF Package Components

Combine all proposal components (cover sheet, discussion section (including the figures and observing list)) into single PDF document. For information on merging PDF documents, see PDF File Merging.

6.0 Instrumentation

Summary: This section contains relevant links for Keck and Palomar instrumentation information.

6.1 Keck Instruments

Keck Telescope instrument information is available through the WMKO Keck Instrument Home Page. Supplementary information on specific instrument status is available at Keck Instrument Availability.

6.2 200-inch Telescope Instruments

P200 instrumentation is summarized on the P200 Observer Page. If you propose to bring your own equipment to P200 please specify the appropriate focus code [Prime Focus (OE-PF), Cassegrain (OE-Cass w/o P3K), Cassegrain + P3K Base (OE-Cass w/ P3K)] on your cover sheet.

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COO Proposal Call / v 2024A-rc2
Last updated: 02 September 2023 JXZ/RJB/AFB/ACM