Observations to be carried out with Chandra during the 12 months of Cycle 14 science operations will be selected from proposals submitted in response to this CfP. Up to 2Ms of Cycle 15 and 1Ms of Cycle 16 observing time may be allocated to time-constrained, multi-cycle observing proposals requesting time that extends beyond Cycle 14.
There are seven types of proposals that may be submitted in response to this CfP; they are detailed in the following sections. In addition, Director’s Discretionary Time (DDT) proposals for observations that cannot be completed in, or cannot wait for, the usual proposal cycle may be submitted at any time (Section 4.8). The CXC reserves the right to reject any approved observation that is in conflict with safety or mission assurance priorities or schedule constraints, or is otherwise deemed to be non-feasible.
There are no restrictions regarding the amount of observing time or the number of targets that may be requested in this category. Proposals may be submitted for single targets with a relatively short observation time, or for larger programs involving multiple targets and/or significant amounts of observing time. All proposals will be reviewed, and a mix of large and small programs will be selected. Proposals requesting observations whose science requires constraints distributed over multiple (up to three) proposal cycles will be considered (Section 3.2.1.14) Observations allocated time in this category will have one year of proprietary time unless a shorter proprietary time interval is requested by the PI.
Large Projects are defined as requiring 300-999 ksec of observing time, regardless of whether they include long-duration observations of single targets or shorter duration observations of many targets. Large Projects must be designated as such by the PI and are encouraged. Up to 4 Msec of the observing time in this Cycle is reserved for Large Projects, subject to the submission of proposals of high scientific merit.
The observations proposed for Large Projects may span up to 3 cycles when required to achieve the scientific goals. In the case of target conflicts with a small proposal, the Selecting Official, based on the recommendation of the peer review, may award the target in question to the smaller proposal. In this case, the proposer of the Large Project may always make use of data taken for the other project once they are made public.
Large Projects are evaluated differently from other proposals. A Large Project is first evaluated and graded along with the other observing proposals by two independent “Topical Science” panels. The graded Large Projects are then passed to the “Big Project” panel which allocates time separately to the LPs and XVPs and makes the final recommendations for an integrated observing plan involving all top-rated proposals to the Selection Official. Although the Big Project panel may recommend shortening a Large Project under exceptional circumstances, it is intended that a Large Project be an all-or-nothing proposition. Observations allocated in this category will be allocated one year of proprietary time unless a shorter time is requested by the PI.
X-ray Visionary Projects (XVPs) should describe a major, coherent science program to address key, high-impact, scientific question(s) in current astrophysics and may span up to 3 cycles when required to achieve the scientific goals. We envision that XVPs will result in data sets of lasting value to the astronomical community. We encourage proposers to describe the legacy value of the data and any data products and/or software they expect to release to the community as part of their project.
XVPs are defined as requiring between 1 and 6 Msec of total observing time including long-duration observations of single targets or shorter duration observations of many targets to address major, key questions in current astrophysics. This category is open to all science topics and must be designated as an XVP by the PI. About 7 Msec of the observing time is reserved for X-ray Visionary Projects, subject to the submission of proposals of high scientific merit.
Observations approved as part of an X-ray Visionary Project will have no proprietary time associated with them, and the data will be made public immediately. XVP projects will be allocated a maximum of 2 Msec of observing time on targets situated above 60º ecliptic latitude.
Proposers planning to submit an
XVP should send a Notice of Intent to
Propose, including the following information: title, PI name, estimated
observing time, preliminary list of Co-Is, and short abstract, to the CXC helpdesk
(cxchelp@head.cfa.harvard.edu)
by
Projects that plan to deliver products, such as source catalogs, high fidelity data products, or software to the community are encouraged to outline these plans in the proposal. A modest funding allocation may be requested in the Stage 2 Cost proposal to facilitate the delivery of such products.
X-ray Visionary Projects will be evaluated and graded by an XVP panel at the peer review in addition to the topical panels. The recommendations of all reviewing panels will then be passed to the Big Project Panel which allocates time, separately, to LPs and XVPs and makes the final recommendations for an integrated program involving top-rated proposals to the Selection Official.
Proposals are
also solicited for Pre-Approved Targets of Opportunity (TOOs). These are
defined to be observations of unanticipated astronomical events, such as a
supernova or a gamma-ray burst that must take place in order to trigger the
observation. The number of times the Observatory can be used to respond to a
It is estimated that the Observatory can support a maximum number of Cycle 14 TOOs of:
|
Number of obsvns1 |
Minimum response time (days)2 |
|
8 |
<1-4 |
|
20 |
4-15 |
|
26 |
15-30 |
|
26 |
>30 |
(1) Follow-up observations that require a rapid response to the initial trigger also count against this allocation. Those with a slower response count as time-constrained observations.
(2) The proposer must select the
Once a
Given the high operational impact of TOOs, no constraints or follow-up observations over and above those included in the proposal RPS forms and recommended by the peer review will be accepted. All follow-up observations whose timing depends on events close to the trigger need to be included in the original proposal forms and will be counted as separate TOOs with category determined by the requested time delay between the event and the observation. All trigger criteria must be specified in the appropriate fields on the RPS form. Follow-up observations that have a longer lead time (> 15 days) are classified as constrained observations.
Those proposing for a
Pre-Approved
Joint Observing Projects may be proposed as follows with the intent to address those situations where data (not necessarily simultaneous) from more than one facility are required to meet the scientific objectives of the proposal. In addition to time on Chandra, time may be requested and awarded via this CfP on one or more of the facilities described below. It is the proposer’s responsibility to provide a technical justification for all observing facilities included in the proposal. A request for simultaneous or otherwise time-constrained observations must be scientifically justified, and the technical justification must include consideration of the relative visibility of the target by all requested facilities. Please note that coordination with ground-based observatories other than NRAO is only available as a preference and will be carried out on a best-effort basis. No time on the joint facilities will be allocated without accompanying Chandra time on the same target, except where noted. Up to 10% and 5% of the available joint time in Cycles 15 and 16 respectively may be allocated to multi-cycle observing proposals if scientifically justified and subject to the continued availability of that time.
This CfP solicits proposals to allow observers interested in using both
the Hubble Space Telescope (HST) and Chandra
to achieve their scientific objectives to submit a single proposal in response
to either HST or Chandra CfPs. The only criteria above and beyond
the usual review criteria are that the project must be fundamentally of a
multi-wavelength nature and that both sets of data are required to meet the
science goals. Simultaneous Chandra
and HST observations should be requested only if necessary to achieve the
scientific goals. Proposers responding to this CfP may request, and be awarded, HST observing time in conjunction
with their Chandra observations. One
hundred orbits of HST observing time are available for this opportunity.
Conversely, up to 400 ksec of Chandra
observing time are available for award as part of the response to HST research
opportunities. However, the Chandra
project can award no more than one HST Target of
Proposers wishing to take advantage of the Chandra-HST arrangements are encouraged to submit their proposal to the Observatory announcement that represents the prime science. The expertise required to best appreciate and evaluate the proposals will be weighted toward the wavelength band of the primary observatory. Demonstration of the technical feasibility for both observatories to produce the necessary data is required, including consideration of the relative visibility of the target(s) to both facilities for the case of time-constrained observations. Technical information about HST is available at http://www.stsci.edu/. General policies for HST observations are described in the latest HST Call for Proposals, available at http://www.stsci.edu/hst/proposing/documents/cp/cp_cover.html. In particular, standard duplication policies described there in Section 5.2 apply to HST observations requested as part of Chandra-HST proposals. Known duplications should be justified scientifically. The Space Telescope Science Institute is prepared to assist observers proposing in response to this opportunity. Questions should be addressed to help@stsci.edu.
Any major requested change to the approved HST portion of a Chandra program such as a change of instrument, wavelength settings, the addition of parallel orbits, etc. requires strong scientific justification, is not normally approved, and may jeopardize the Chandra portion. Due to a backlog of certain HST observations, the HST Cycle 20 will have specific Right Ascension observing restrictions. Please review the HST Call for details on these restrictions.
If a science project requires observations with both XMM-Newton, sponsored by the European Space Agency, and the Chandra X-ray Observatory, then a single proposal may be submitted to request time on both Observatories to either the most recent XMM-Newton Announcement of Opportunity or to this Chandra CfP so that it is unnecessary to submit proposals to two separate reviews.
By agreement with the Chandra Project, the XMM-Newton Project may award up to 400 ksec of Chandra observing time. Similarly, the Chandra Project may award up to 400 ksec of XMM-Newton time. The time will be awarded only for highly ranked proposals that require use of both observatories and shall not apply to usage of archival data. The only criterion above and beyond the usual review criteria is that both sets of data are required to meet the primary science goals. Proposers should take special care in justifying both the scientific and technical reasons for requesting observing time on both missions. Simultaneous Chandra and XMM-Newton observations should be requested only if necessary to achieve the scientific goals. No Targets of Opportunity, either pre-Approved or unanticipated, will be considered for this cooperative program. For this CfP, no XMM-Newton time will be allocated without the need for Chandra time to complete the proposed investigation.
Establishing technical feasibility is the responsibility of the observer, who should review the Chandra and XMM-Newton (http://heasarc.gsfc.nasa.gov/docs/xmm/xmmgof.html) documentation or consult with the CXC HelpDesk (http://cxc.harvard.edu/helpdesk/). For proposals that are approved, both projects will perform detailed feasibility checks. Both projects reserve the right to reject any approved observation that is in conflict with safety or mission assurance priorities or schedule constraints, or is otherwise deemed to be non-feasible. Note that simultaneous longer-duration observations with XMM-Newton that require Chandra satellite pitch angles violating the conditions discussed in Section 2.3 may not be feasible. Any observation(s) deemed to be not performable as indicated above would cause revocation of observations on both facilities.
By agreement with NOAO, proposers interested in making use of observing facilities available through NOAO (including Gemini, CTIO, KPNO, SOAR and WIYN, but not facilities made available through the TSIP or ReSTAR programs) as part of their Chandra science may submit a single observing or archival research proposal in response to this CfP. The award of NOAO time will be made to highly ranked Chandra proposals and will be subject to approval by the NOAO Director.
The primary criterion for the award of NOAO time is that both Chandra and NOAO data are required to meet the scientific objectives of the proposal. Both Chandra observing and archival research proposals are eligible. The highest priority for the award of NOAO time will be given to programs that plan to publicly release the optical data in a timely manner (i.e., shorter than the usual 18-month proprietary period) and that create databases likely to have broad application. NOAO plans to make up to 5% of the public time each semester on each telescope available for this opportunity. Time on the Gemini telescopes will be restricted to no more than 40 hours per year per telescope, and will be scheduled as queue observations. The Gemini queue time is distributed across three priority bands (see http://www.gemini.edu for an explanation of the bands) as follows: NOAO will schedule no more than 15 hours of the Chandra/NOAO time as Band 1, 15 hours as Band 2, and 10 hours as Band 3. In addition, the available observing time is divided roughly equally between the A and B semesters covered by the Chandra cycle, for a maximum of 20 hours per semester on each telescope. Proposers wishing to make use of this opportunity must provide the following additional NOAO-related information as part of their Chandra proposal:
Demonstration of the technical feasibility of the proposed NOAO observations is the responsibility of the proposer. Detailed technical information concerning NOAO facilities may be found at http://ast.noao.edu/observing. Proposals lacking sufficient detail may not be scheduled by NOAO.
If approved for NOAO time, successful PIs will be required to submit the standard NOAO forms providing detailed observing information appropriate to the telescope and instrument combination(s) awarded. NOAO will perform feasibility checks on the proposed observations and reserves the right to reject any observation determined to be unfeasible for any reason. Such a rejection could jeopardize the entire proposed science program and impact the award of the Chandra observing time as well.
In addition, for NOAO time on Gemini (only), successful PIs will be required to submit a full scientific justification to NOAO on the standard NOAO proposal form. NOAO will review the proposal in order to determine the Gemini queue band into which the observations will be placed.
By agreement with NRAO, proposers
interested in making use of the NRAO Expanded Very Large Array (EVLA), Very
Long Baseline Array (VLBA) and Green Bank Telescope (
The primary criterion for the award of NRAO time is that both Chandra and NRAO datasets are essential to meet the scientific objectives of the proposal. No NRAO time will be allocated without Chandra time.
NRAO plans to make up to 3% of EVLA, VLBA and
For Chandra Cycle 14, observations with the EVLA will be limited to a total bandwidth of 2 GHz per polarization.
Proposers wishing to make use of this opportunity must provide the following NRAO-related information as part of their Chandra proposal:
EVLA observing will be supported only as Open Shared Risk Observing, which is described at http://science.nrao.edu/facilities/evla/early-science/osro.
Be aware that some Chandra targets might not require new NRAO observations because the joint science goals can be met using:
Detailed technical information concerning the NRAO telescopes can be found at:
http://science.nrao.edu/evla/index.shtml (EVLA),
http://science.nrao.edu/facilities/vlba, and http://science.nrao.edu/facilities/gbt.
In particular, technical information required for a proposal can be found at:
http://evlaguides.nrao.edu/index.php?title= Observational_Status_Summary,
http://science.nrao.edu/astro.obstatus/current/ (VLBA), and
http://www.gb.nrao.edu/gbtprops/man/GBTpg.pdf (GBT).
If approved for NRAO time, successful PIs will be contacted by the NRAO
Scheduling Officers. The successful PIs
for
NRAO will perform final feasibility checks on the proposed observations and reserves the right to reject any observation determined to be infeasible for any reason. Such a rejection could jeopardize the success of the joint science program.
By agreement with the Suzaku Project, proposers interested in making use of Suzaku time as part of their Chandra science investigation may submit a single proposal in response to this Chandra CfP. The award of Suzaku time will be made to highly ranked Chandra proposals and will be subject to approval by the Suzaku Project.
The primary criterion for the award of Suzaku time is that both Chandra and Suzaku data are required to meet the scientific objectives of the proposal. Suzaku time will not be awarded without accompanying Chandra observing time. The Suzaku Project is making available up to 500 ksec of Suzaku observing time available to such joint science proposals. Coordinated observations are allowed, if judged feasible. Chandra Cycle 14 is expected to overlap with Suzaku Cycles 7 (2012 April through 2013 March) and 8 (2013 April through 2014 March).
A maximum of 75 ksec on Suzaku
can be time-constrained for science reasons, including coordinated
observations, roll, phase or window constraints, or Targets of
Opportunity. No
Proposers wishing to make use of this opportunity must provide the following additional Suzaku-related information as part of their Chandra proposal:
1) Enter the total requested Suzaku observing time in the relevant Chandra RPS box; and
2) Include a full and comprehensive scientific and technical justification for the requested Suzaku observing time, including the expected count rates (from simulations or previous Suzaku observations), and the desired observing modes.
It is the responsibility of the proposer to demonstrate the feasibility of the proposed Suzaku observation. Detailed technical information concerning Suzaku may be found at http://www.astro.isas.jaxa.jp/suzaku/. The Suzaku Guest Observer Facility and Project Scientist will make feasibility assessments of the proposed observations independently of the Chandra review. Proposed Suzaku observations determined to be infeasible will be rejected. Such a rejection could jeopardize the entire proposed science program and impact the award of the Chandra observing time as well.
If Suzaku time is approved, successful PIs will then be required to submit the standard Suzaku cover and target forms to the Suzaku Guest Observer Facility via the RPS to provide the required information about observing strategy and instrument configurations in a form amenable to the Suzaku scheduling software.
Suzaku datasets obtained under this agreement will be proprietary to the PI for one year after the performance of the observation, and will subsequently be released publicly via the HEASARC.
Research that is primarily Theoretical/Modeling in nature can have a lasting benefit for current or future observational programs with Chandra, and it is appropriate to propose such programs with relevance to the Chandra mission. Theoretical/Modeling research should be the primary or sole emphasis of such a proposal. Analysis of archival data should not be the goal of the project. Archived data may be used only to show how Chandra observations may be better understood through the results of the proposed Theory/Modeling research. Theory/Modeling proposals must be submitted using the same proposal format as observing proposals, and the proposal type “Theory” should be checked on the electronic submission.
A Theory/Modeling proposal should address a topic that is of direct relevance to Chandra observing programs, and this relevance must be explained in the proposal. (Research that is appropriate for a general theory program should be submitted to the Science Mission Directorate’s Astrophysics Theory Program, solicited in the annual Research Opportunities in Space and Earth Sciences (ROSES) NASA Research Announcement and/or other appropriate funding sources.) The primary criterion for a Theory/Modeling proposal is that the results must enhance the value of Chandra observational programs through their broad interpretation (in the context of new models or theories) or by refining the knowledge needed to interpret specific observational results (for example, a calculation of cross sections). As with all investigations supported through this CfP, the results of the Theoretical/Modeling investigation should be made available to the community in a timely fashion.
A Theory/Modeling proposal must include an estimated amount of funding in the Stage 1 submission and must provide a narrative within the science justification section that describes the proposed use of the funds. Detailed budgets are not requested in Stage 1, however, and are due only in Stage 2.
The scientific justification section of the proposal must describe the proposed theoretical investigation and also the anticipated impact on observational investigations with Chandra. Review panels will consist of observational and theoretical astronomers with a broad range of scientific expertise. The reviewers will not necessarily be specialists in all areas of astrophysics, particularly theory, so the proposals must be written for general audiences of scientists. The proposal should discuss the types of Chandra data that would benefit from the proposed investigation, and references to specific data sets in the Chandra data archive should be given where appropriate. The proposal should also describe how the results of the theoretical investigation will be made available to the astronomical community, and on what time scale the results are expected.
This CfP also includes the opportunity to propose investigations based on
data in the Chandra public archive
for part or all of the study. Proposals for which archival data is the major
focus of the investigation should select the “Archive” category on the RPS
form. A PI may link an archival research proposal with an observing proposal to
extend an existing sample to perform the same science. There is no restriction
on the amount of existing Chandra
data that may be proposed for analysis. The Chandra
website (http://cxc.harvard.edu/)
contains information on the data that are available in the archive. The data
currently available from the Chandra
Data Archive may be browsed and visualized through the
The data may also be accessed through this website (see also Section 3.5). All on-orbit calibration data are placed directly in the archive. Data from Director’s Discretionary Time (DDT) observations (Section 4.8) are placed in the archive no later than three months after receipt by the PI, while other proprietary observations are archived no later than one year after receipt by the PI. XVP data have no proprietary period and are placed in the archive coincident with receipt by the PI. A bibliographic interface allows simultaneous browsing of the Chandra Data Archive and the literature (http://cfa.harvard.edu/cgi-gen/cda/bibliography). See Section 6.1.3 for further details on archiving browsing.
Archival Research proposals must include an estimated amount of funding in the Stage 1 submission and must provide a brief narrative within the science justification section that describes the proposed use of the funds. Detailed budgets are not requested in Stage 1 and are due in Stage 2.
We will accept archival proposals which make use of the Chandra Source Catalog as all or part
of the proposed science program. The
current release (1.1) of the catalog includes information about sources
detected in a subset of ACIS and
The catalog includes sources detected with flux estimates that are at least 3 times their estimated 1 sigma uncertainties in at least one energy band (typically corresponding to about 10 net source counts on-axis and roughly 20-30 net source counts off-axis). In the current release of the catalog, multiple observations of the same field (if they exist) are not co-added prior to performing source detection. Instead, source detection is performed on each observation individually, so that the flux threshold applies to detections from each observation separately.
Prospective users of the catalog should be aware of the selection effects
that restrict the source content of the catalog and which may limit scientific
studies that require an unbiased source sample.
Users are urged to review the catalog Caveats and Limitations prior to using
the
For more information on the Chandra
Source Catalog, please refer to the public catalog web pages at http://cxc.harvard.edu/csc. The data used for the
Unanticipated Targets of Opportunity or those that cannot wait for the next proposal cycle may be proposed for observation using Director’s Discretionary Time (DDT) at any time. Proposals for DDT must be submitted electronically through the RPS as described in Section 5.3. Note that the RPS form for DDT is different from that for ordinary proposals. The DDT form may be found on the CXC website by selecting the “Proposer” button and then “Targets of Opportunity” and “Director’s Discretionary Time” (http://cxc.harvard.edu/soft/RPS/Chandra_RfO.html). More information is available in Section 3.2.
