Chandra Proposal Submission Help

CPS provides a facility for composing and submitting Chandra Proposals. Electronic submission of forms and scientific justification is required.

Home The Home page displays a table of proposals owned by or shared with the current user. They may be proposals you have withdrawn or submitted, are from previous cycles, or are proposals that someone else owns where you are listed as the Principal Investigator(PI) or as a Co-Investigator(CoI). A gray background on a table row means the proposal is not editable but can be viewed, yellow background means the proposals has been submitted or withdrawn, but can edited still, and a white background means the proposal is in progress and has not been submitted or withdrawn.

The "Own?" column indicates whether or not you are the person responsible for the proposal. These are proposals that you are actively working on, or are proposals that you have submitted or withdrawn. You can only edit those proposals that you both own and that are in an editable state (e.g. not withdrawn, not from a previous cycle).

Buttons on the Home Page:

Principal Investigator
Co-Investigators For details of any collaborators, etc. All investigators listed on the CPS form will receive an email after the submission deadline containing basic information such as proposal number, PI, co-investigators, proposal title, and abstract.

Joint Optional. The Joint Proposal section should ONLY be filled out if this is a joint proposal which also requests time on one or more of the facilities listed below. Please refer to the information on Joint Proposals in the Chandra Call for Proposals and/or on the Proposer page: If proposing joint time for future cycles, include the total joint observing time request across all cycles here. The specific joint observatory requests by cycle must be described in the Remarks fields of the Target pages.

A small amount of observing time has been reserved in the programs of HST, NRAO, XMM, and Chandra to be awarded by the review panels of the other observatories Users may apply to HST, NRAO, or XMM and be awarded Chandra time and vice versa.

Those proposing for Chandra time in response to this call may also apply for time from the following facilities:

ObservatoryJoint Time Available
HST Maximum of 250 orbits available.
XMMMaximum of 1 Msec available.
SwiftMaximum of 500ks available.
NuSTARMaximum of 1 Msec available.
NOAOUp to 5% of the time on each telescope available for the Joint opportunity. Details of telescope/instrument combinations available at a given time are provided on the web at:
NRAO3% of the NRAO telescopes (max 5% in any one configuration): NRAO/VLA, NRAO/VLBA, and NRAO/GBT .

No Joint time will be allocated by the Chandra peer review without allocation of Chandra time except in the case of winning Archive proposals that request NOAO night(s).

Multicycle proposals requesting joint time may be allocated up to 10% of cycleN+1 and 5% of cycleN+2 of the available joint time if scientifically justified (subject to the continued availability of that time). If proposing joint time for future cycles, include the total joint observing time request across all cycles.

Note: If close coordination between space-based observatories is required, you should set the Must this observation be coordinated with that of another space-based observatory? option to Y, whether or not your current proposal requests joint time awarded through Chandra.

Target Pointing

Target Observing Time
Target Instrument

ACIS Required Parameters For faint sources (~< 0.01 cps), these are the only parameters that must be set.

ACIS Optional Parameters that affect PILEUP The custom parameters are available so users can mitigate the effects of pileup and avoid exceeding the telemetry saturation limit.

ACIS Optional Parameters that affect TELEMETRY Before event candidates are written to telemetry, they are subjected to three sets of filters, each of which can cause them to be rejected. The filters can reject events by their grade code*, by their energy, and by their spatial location on the CCD array. The order in which these filters are applied is unimportant.

* At the present time, the proposer cannot change the set of grade codes to be rejected by the on-board grade filter; they were chosen to exclude only those event candidates that are almost certainly not caused by target X-rays. This is discussed in the Non-X-ray Background section of the Chandra Proposer's Guide.)

Target Constraints This section contains additional parameters for a time critical observation.

If any constraint is required, the observation is considered time constrained and will be subject to the limits set for the number of approved constrained observations during the Chandra Peer Review.

The types of constraint are:

On other pages: 'Monitoring', 'Grouping' and 'TOO Followup' observations are mutually exclusive.

'Grouping' and 'Split Interval' observations are mutually exclusive.

'Uninterrupted' and 'Split Interval' observations are mutually exclusive.

Note:If any constraint is set to Y (i.e., required), the observation is time constrained and therefore subject to the limits set for the number of approved constrained observations during the Chandra Peer Review. BEFORE SUBMISSION, please check the SlewTax/Resources in the "Target Checks" section to estimate the constraint difficulty level of each target and the total slew tax for your proposal.

You may want to use the PRoVis tool to investigate Chandra spacecraft roll, pitch and visibility for your target as a function of date. Chandra Mission Planning schedules all observations, but information from PRoVis can be especially useful for proposers whose observations require constraints.

Target Remarks
TOO Details If this is the trigger target for a TOO, please specify the exact CXC response window, probability, and trigger criteria . These fields should NOT be specified if this target is a TOO followup, even if the followup specifies a different instrument configuration than the trigger target. The response to a TOO will be classified according to the minimum time delay between trigger and observation. The faster the Chandra response, the more difficult and the more limited the number of TOOs allowed.
Supporting Files

Target Checks
  • Would the P.I. be willing to participate in an upcoming Chandra peer review?
    Optional, and for CXC internal use only.

    At the Chandra peer review, which normally takes place about three months after the proposal deadline, a dozen panels review and discuss all submitted proposal in specific science categories. Each panel includes 7 or 8 panelists and one chair to assess about 60 proposals. Proposals are available to reviewers about 4 weeks prior to the review and the CXC requests that preliminary grades be sent electronically in advance of the review to aid with prioritization of discussion time during the review itself. For each proposal, a primary reviewer is responsible for writing a short assessment which will be sent to the proposer. The review takes 2 full days plus travel and time to read the proposals in advance. Travel expenses are paid by the Chandra project.

    Note that a Yes answer, while deeply appreciated, does not guarantee participation in an upcoming Chandra peer review, since the CXC must balance many factors and avoid conflicts when composing peer review panels. Your answer will have no bearing on the success of your Chandra proposal(s).

  • I have carefully reviewed this proposal and associated files for DAPR compliance.
    A non-exhaustive list of Dual Anonymous Peer Review (DAPR) violations that may result in a proposal being removed from the peer review includes:
    • Using first-person pronouns in conjunction with references as in "In [23] we demonstrated..." and "...our technique described in [5]..." in the science justification.
    • Naming the proposing institution(s) and proposing team member(s) in the science justification.
    • Using text references instead of the required numbered references ("Smith et al. 2022" versus the required "[2]" style referencing), and, including the institution name in budget descriptions (for archive and theory proposals).

  • I have reviewed my application and believe it to be ready for submission.
    Check this box when your proposal is final. Then click the "Submit" button to submit the proposal. After you submit a proposal, you are returned to the CPS Home page.
  • 10.11.2 Tuesday, November 15, 2022
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