3.7 Joint HST-Spitzer Observing Proposals

If your science project requires observations from both HST and Spitzer, then you can submit a single proposal to request time on both observatories. This avoids the "double jeopardy" of having to submit proposals to two separate reviews. Technical information about Spitzer instrumentation and observations is available from the Spitzer Science Center (SSC) Web site and specific questions can be addressed to the SSC Help desk (help@spitzer.caltech.edu).

There are two types of Joint HST-Spitzer proposal: Regular proposals ( Section 3.7.1), that require relatively modest allocations on Spitzer; and the new category of Coordinated HST-Spitzer proposals ( Section 3.7.2), that require more substantial allocations. In either case, evaluation of the technical feasibility is the responsibility of the observer, who should review the Spitzer documentation or consult with the SSC (see Section 9.4.2 for details). For proposals that are approved, the SSC will perform detailed feasibility checks in Spitzer Cycle 4. The SSC reserves the right to reject any previously approved observation that proves infeasible, impossible to schedule, and/or dangerous to the Spitzer instruments. Any Spitzer observations that prove infeasible or impossible could jeopardize the overall science program and may cause revocation of the corresponding HST observations. Duplicate Spitzer observations may also be rejected by the SSC.

Joint HST-Spitzer Proposals must be identified in the 'Special Proposal Types' section of the proposal (see Section 8.10). Also, you must include technical information about the Spitzer observations in the 'Coordinated Observations' section of the proposal (see Section 9.4.3).

3.7.1 Regular HST-Spitzer proposals

By agreement with the SSC, STScI will be able to award up to 125 hours of Spitzer observing time. Similarly the SSC will be able to award up to 90 orbits of HST time to highly rated proposals awarded Spitzer time in its TAC process. The only criterion above and beyond the usual review criteria is that the project is fundamentally of a multi-wavelength nature, and that both sets of data are required to meet the science goals. Spitzer time will only be awarded in conjunction with HST observations (and should not be proposed for in conjunction with an Archival Research or Theory Proposal). Proposers may request up to 50 hours of Spitzer time in any one HST Cycle 16 proposal. Any program requiring 50 hours or more of Spitzer time should be submitted as a Coordinated HST-Spitzer proposal.

Proposers may not request either high-impact (<1 week; minimum 48 hours) or medium-impact (1-5 week) ToO observations. Spitzer high- and medium-impact ToOs require substantial time overheads, and requests should be directed to the Spitzer TAC. See Appendix E of the Spitzer Cycle-4 Call for Proposals for details.

Proposals for combined HST and Spitzer observations should be submitted to the observatory that represents the prime science (not to both observatories). Similarly, proposals for observations with HST, Spitzer and Chandra ( Section 3.5) should only be submitted to the observatory that represents the prime science. The Spitzer Cycle 4 deadline is 14 February 2007. While there is multi-wavelength expertise in the review panels for both observatories, typically the HST panels will be stronger in optical/UV science and the Spitzer panels in infrared science.

3.7.2 Coordinated HST-Spitzer proposals

Scientific programs that require substantial allocations of time on both HST and Spitzer are not accommodated easily by Regular HST-Spitzer proposals. The new category of Coordinated HST-Spitzer proposals is designed to enable large-scale projects that require both Great Observatories. Programs submitted in this category must require at least 70 orbits of HST time and at least 50 hours of Spitzer observations. These proposals are therefore equivalent to Large GO proposals allocated by HST and Large Programs allocated by Spitzer.

As described in Section 6.1.3, Coordinated HST-Spitzer proposals will be assessed by a Joint TAC, drawn from both the HST and Spitzer TACs. As an aid in determining both the size and membership of the Joint TAC, proposers considering submitting a Coordinated HST-Spitzer Proposals are required to submit a non-binding Notice of Intent (NOI). The NOI should include the following information: the name of the PI, names of known co-Is, the title of the proposal, a short (<200 word) abstract and an estimate of the time to be requested on both HST and Spitzer.

Notice of Intent to submit a Coordinated HST-Spitzer proposal should be submitted by e-mail to I.N. Reid (inr@stsci.edu) and to L. Storrie-Lombardi (lisa@ipac.caltech.edu) by 1 December 2006.

The Coordinated HST-Spitzer proposals themselves should be submitted to both observatories. The deadline for submission is the HST deadline, 26 January 2007. As described in Section 6.1.3, proposals in this category will be reviewed separately by a joint HST-Spitzer TAC, comprised of members of the HST TAC and the Spitzer TAC. HST will allocate up to 300 orbits and Spitzer up to 500 hours of observing time for programs in this category.