1.1     The Chandra Program: Call for Proposals

We invite scientists to participate in Cycle 10 of the Chandra X-ray Observatory’s (CXO) science program. The Chandra program is sponsored by NASA’s Science Mission Directorate (SMD) and managed by the NASA Marshall Space Flight Center (MSFC). The Chandra X-ray Center (CXC), which is funded by NASA via a contract to the Smithsonian Astrophysical Observatory (SAO) in Cambridge, MA, has the responsibility for managing the Chandra science program, carrying out the Chandra Education and Public Outreach (EPO) program, conducting the peer review that recommends the allocation of observing time and funds to the user community, selecting the proposals, and operating the Chandra spacecraft. The Chandra X-ray Observatory is described in Chapter 2.

The funding of all awards associated with this Call for Proposals (CfP) flows from NASA through SAO and the CXC to the Awardees. The CXC is the organizational unit within SAO that carries out SAO’s contractual obligation to operate the Chandra X-ray Observatory and solicit proposals and when used in this document will encompass the NASA/SAO/CXC interrelationship.

1.2     Proposal Review Process: Deadlines and Schedule

Science proposal submission and review will be conducted in two stages to minimize the burden of proposal preparation. For details, please refer to Chapter 5:

·       Stage 1: Involves the scientific and technical merits of the proposed investigation. Evaluation criteria include overall scientific merit, relevance to the Chandra program and the competence of the proposers (Section 7.1).

·       Stage 2: The PIs of those proposals selected in Stage 1 will be invited to submit a cost proposal for the Stage 2 review (Chapter 8) and will also be given an opportunity to submit an Education/Public Outreach (EPO) proposal (Chapter 9).

Table 1.1     Schedule and Deadlines for the CfP Cycle

event	date
CfP Release	14 December 2007
Science Proposal Deadline (Stage 1)	6 p.m. EDT, 20 March 2008
Peer Review	16-20 June 2008
Selected Proposals Announced	Early July 2008
Budget Deadline (Stage 2)	6 p.m. EDT, 18 September 2008
Cost Review	October 2008
Stage 2 Final Selection	November 2008
EPO Electronic Deadline	5 p.m. EDT, 24 October2008
EPO Hardcopy Deadline	4 p.m. EDT, 29 October 2008
EPO Review	December 2008
Cycle 10 Starts	About December 2008

Late Proposals will not be considered. We recommend submission well before the deadline.

1.3     Summary of the CfP

This CfP solicits basic research proposals for participation in the program for the conduct of space science observations and subsequent analysis of the resultant scientific data from the Chandra X-ray Observatory (CXO). The CfP also solicits proposals for research that makes use of publicly available archived Chandra data and for theoretical and modeling studies related to the Chandra mission. A separate supplementary CfP will be issued following the Stage 1 review to solicit EPO proposals from eligible PIs whose Chandra proposals have been selected in Stage 1. The primary goal of the Chandra mission is the investigation of the nature and physics of astronomical objects as revealed through their X-ray emission.

This CfP offers the opportunity for the submission of seven different types of proposals (Chapter 4) and two types of EPO proposals.

Types of Science Research Proposals:

1. General Observing Projects (GO) involving new Chandra observations, generally (but not limited to) requiring less than 300 ksec of observing time (regardless of the number of objects observed);
2. Large Observing Projects (LP) involving new Chandra observations that require 300 ksec or more (regardless of the number of objects observed) and designated as LPs by the PI;
3. Very Large Observing Projects (VLP) involving new Chandra observations that require 1 Msec or more (regardless of the number of objects observed) and designated as VLPs by the PI;
4. Target of Opportunity (TOO) Projects that are triggered by the occurrence of an unanticipated astrophysical phenomenon (e.g., a supernova);
5. Joint Observing Projects that require multi-wavelength sets of data taken by Chandra and one or more of the facilities described in Section 4.5;
6. Archival Research Projects that use data from the Chandra archives or the Chandra Source Catalog; and
7. Theory/Modeling Projects that seek to better understand and interpret the data that have been taken with Chandra, or that seek to determine what new observations might be taken to test a hypothesis.

The observations selected as a result of this CfP will be implemented during a one-year period beginning about December 2008. Based on guidelines set by the Chandra Observing Policy (Chapter 3), 3.5% (700 ksec) of the on-target observing time available during this cycle is allocated to calibration observations, and 700 ksec is allocated to Director’s Discretionary Time (DDT). Following this allocation, 85% of the remaining time is available for General Observations (GO), and 15% is allocated to Guaranteed Time Observations (GTO). The time available for General Observers (including Large and Very Large Projects) under this CfP is estimated at about 17 Msec. It is anticipated that further opportunities for participation in the Chandra Research Program will be announced annually, including the analysis of the increasing body of archival data.

1.4     Cancellation of the CfP

The CXC reserves the right to make no awards under this CfP and to cancel this CfP. The CXC, the Smithsonian Institution, and NASA assume no liability should the CfP be cancelled or for anyone’s failure to receive notification of a cancellation.

1.5     What’s New in Cycle 10

• Pitch Angle Restrictions:  Due to the changing thermal environment and constraints, pitch angle restrictions remain somewhat fluid. Information on pitch angle restrictions can be found in Section 2.3.  Since the situation may change at short notice, proposers are urged to also check the CXC website for any updates during the proposal preparation period.

• Proposal Page Limit/Font Limits:  Page limits and font limits are listed in Table 5.2.  They have not changed, but please note that the CXC routinely removes extra pages from proposals which violate the page limits. Proposals violating the font size (11 pt. minimum) or margin limits will be rejected.

• Joint Spitzer time: Given the uncertainty in the duration of Spitzer’s Cycle 5 and the timing between Cycle 5 and Chandra’s Cycle 10, we are not accepting joint Spitzer proposals in Cycle 10. We anticipate resuming joint Spitzer proposals during a Spitzer Warm Mission.

• Joint RXTE Time:  Continuation of the RXTE mission is currently contingent upon the outcome of NASA Headquarters’ Astrophysics Division Senior Review of Operating Missions 2008. The RXTE project will make joint observing time available if the mission is recommended to continue operations beyond the current shut-off date of 2009 February 28. The outcome of the Senior Review is expected by July 2008.

  Joint Chandra/RXTE proposals submitted for Chandra Cycle 10 will be peer-reviewed on science content as usual, but reviewers will be provided with the most current news available, and may be asked to provide a second grade considering the proposal without RXTE time.

• RPS updates:
  • NRAO time: NRAO time requests may now include the GBT as well as VLA and VLBA. The RPS form has been revised to include two fields, the first one to select the telescope(s) and the second for the total time requested on all NRAO telescopes
  • Coordinated observations: A new field requests the maximum scientifically-permitted interval encompassing the Chandra observation and those of the coordinating observatory(ies).
  • Aimpoint offsets: The default aimpoint was updated on 19 February 2007. Details are available in the RPS help text and in the Proposers’ Observatory Guide (POG).
  • ACIS-I Signal-to-Noise information: In order to optimize the instrument configuration for non-grating ACIS-I observations there are two additional questions in the ACIS section of the RPS target form concerning your expectations for the signal-to-noise and plans for spectral analysis of your dataset.

• Cost Proposal Review: Starting in Cycle 10, Cost Proposals that request a budget less than or at (or very close to) the fair share budget allocation will not be subject to an external review. The fair share budget allocation will use essentially the same algorithm as used to compute the target budget in previous cycles. This is based on scientific and technical evaluation by the peer review, allocated time, number of targets and the complexity of planned analysis for observing proposals. In the case of Archival Research or Theory/Modeling proposals, the fair share allocation is based on the proposed budget combined with the scientific/technical rating by the Peer Review and the availability of funds. A PI who wishes to request a budget higher than the fair share allocation should submit a detailed justification explaining why a higher level of funding is needed. Such proposals will be subject to an external review by a subset of the Stage 1 science reviewers.

• ObsVis (Observation Visualizer) Application:  The downloadable version of the Chandra Observation Visualization software (ObsVis) has been substantially re-written for Cycle 10. The new version reproduces and expands upon the existing functionality including, for example, the ability to view and manipulate multiple fields-of-view to allow observers to plan grids of observations.

  The new ObsVis requires imaging software DS9 version 5.0 or later and is not backwards compatible with previous versions. It is downloadable with CIAO4.0, planned for release in mid-December.  Detailed information is available on the CXC website. WWW ObsVis: The visibility/pitch/roll-angle tool is not part of the new ObsVis. It will continue to be available on the CXC website at:  http://obsvis.harvard.edu/  

• Archive Proposals and the Chandra Source Catalog:  Proposers should be aware that the first release of the Chandra Source Catalog is expected in the fall of 2008.  We will accept archival proposals which make use of this catalog as all/part of the planned science program. Please refer to Section 4.7 for more information.

• Initial Proposal Parameter Signoff (IPPS): Starting in Cycle 9, an initial “LTS-ready” (Long Term Schedule) observation parameter check will be carried out by CDO in communication with all PIs and observers.  See Section 7.3 for more details.

• Large and Very Large Projects:  The total amount of observing time available for these proposal types will remain at 6 Msecs (maximum) in Cycle 10. However the previous requirement that at least 3 Msecs be allocated to LPs will be removed. All LP and VLP proposals will compete for the full 6 Msecs of time with the final allocation between types being recommended by the peer review based on scientific merit.

1.6     Proposal Submission

Science proposals must be submitted electronically via the Remote Proposal System (RPS) software (//cxc.harvard.edu/cgi-bin/RPS/Chandra/RPS.pl), available on the CXC website; see Section 5.3 for more details. Cost proposals will also be submitted electronically using forms available from the CXC website; see Chapter 8 for more details.  EPO proposal submission is discussed separately in Chapter 9.

1.7     How to Get Help

Questions concerning the Chandra mission and requests for assistance in Stage 1 proposal submission may be addressed to the Chandra Director’s Office (CDO) via the HelpDesk at: http://cxc.harvard.edu/helpdesk/ or by email to cxchelp@cfa.harvard.edu.

The full contact information for the CDO is:

Chandra Director's Office
Chandra X-ray Center
Smithsonian Astrophysical Observatory
60 Garden Street, Mail Stop 6
Cambridge, MA 02138-1516

Telephone: (617)495-7268
FAX: (617) 495-7356
Email: cxchelp@cfa.harvard.edu

For questions concerning the Stage 2 Cost Proposals or EPO proposals, please refer to the information in Chapters 8 and 9.

1.8     Relevant Documents and Web Addresses

Documents recommended to proposers for additional information are listed in Table 1.2. Web addresses, which may be useful in preparing scientific, cost, and EPO proposals in response to this CfP, may be found in Table 1.3.

Table 1.2.     Useful Documents

Table 1.3.     Web Addresses