NuSTAR Proposals and Tools
While NuSTAR was initially approved by NASA as a 2-year Principal
Investigator-led (PI-led) mission, NuSTAR has now been approved to continue
operations through 2018 (subject to review by the 2016 NASA Astrophysics
Senior Review of Operating Missions) and to have a dedicated Guest Observer
(GO) Program. There are several
opportunities for guest observers in the general scientific community
to propose for NuSTAR observations.
Starting in 2014, NuSTAR solicits guest observer proposals from the
general scientific community. The first cycle call for proposals was
released on August 26th, 2014. Here are key dates for the current
|Date||Important Cycle 1 Event|
|August 26th, 2014||NuSTAR Cycle 1 Announcement of Opportunity
|September 17th, 2014||List of planned NuSTAR targets released
|November 3rd, 2014||Last day to request assistance for pointings with heavily contaminated stray light
|November 25th, 2014||Cycle 1 proposals due 4:30pm EST
|February, 2015||Approximate date of Cycle 1 peer review
|April 1, 2015||Approximate start of Cycle 1 guest observations
For more information, see the the guide for NuSTAR cycle 1 proposers.
Currently NuSTAR and XMM-Newton have an arrangement which makes
available joint observing time for both observatories. This resource
allows observers to combine the powers of both observatories to bear
on their scientific problems. This resource is extremely limited, so
proposers should be sure to describe how their proposed observations
exploite the unique capabilities of both observatories. Proposals for
this observation time go through the XMM proposal process.
- XMM Cycle 14. Is now closed. Approximately 1.5 Ms of joint XMM-Newton and NuSTAR observation time was made available through the XMM-Newton
Cycle 14 AO. The start of observations is in May 2015.
- XMM Cycle 13. Is now closed. Approximately 1.5 Ms of joint XMM-Newton and NuSTAR observation time was made available in the XMM-Newton Cycle
13 AO which was released on 27 August 2013. 62 such proposals were
in fact submitted. Results can be found on the XMM-Newton OTAC Results page.
Currently NuSTAR and Chandra also have an arrangement which makes
available joint observing time for both observatories. An opportunity
to propose for NuSTAR observing time as part of this joint observing
program is being made available through the
Chandra calls for proposals.
- Chandra Cycle 17. Expected to be similar to Cycle 16.
- Chandra Cycle 16. Is now closed. Up to 500 ksec of NuSTAR
observing time were made available through the Chandra proposal
process, which closed on March 13, 2014. Results of the review can
be found here.
The NuSTAR project has developed tools and documentation to help
NuSTAR Observatory Guide: The NuSTAR team has developed a
document which describes the technical capabilities, concept of
operation and key information for proposers. Download the current version
NuSTAR Observatory Guide (released August 26, 2014).
Count Rate and Spectral Simulations: The standard HEASARC count rate and spectral
simulations tools, WebPIMMS and WebSpec, are available for NuSTAR
was updated on March 5, 2014 to include the most recent NuSTAR responses
and background files. The NuSTAR responses
and background files can also be downloaded directly from the
Caltech SOC web site and used to simulate spectra in spectral
analysis software such as XSPEC. See Section 4.7 of the
NuSTAR Observatory Guide for
a detailed discussion of how to simulate NuSTAR spectra using XSPEC.
Other issues which proposers should take under consideration are:
- Target Visibility: The
NuSTAR Science Operations Center Target Visibility checker
allows input of the RA and Dec coordinates of a source and finds the times
when it is visible to NuSTAR subject to viewing constraints.
- Timing: The
NuSTAR Clock Correction Files keep the NuSTAR relative time (after
barycentric corrections) accurate to ~2 ms and account for drifts in the NuSTAR
clock caused by temperature variations, etc. New clock files will be produced
as the mission continues on a ~monthly basis.
- Stray Light: Extremely bright X-ray sources (>100 mCrab in the
3-79 keV band) within 1 to 5 degrees of a target can cause issues with
elevated backgrounds due to stray light. The presence of such confusing
sources is reported by the
NuSTAR Science Operations Center Target Visibility checker.
- Dead Time: NuSTAR has a triggered readout, similar to a proportional
counter but unlike a CCD, so it does not suffer from pile-up effects. However,
dead time becomes significant for sources above ~50 ct/s, and this must be
factored into integration time estimates. Quantitative estimates of the effect
of dead time on exposure estimates are included in the latest version of
WebPIMMS. Further details of the effects of dead time on bright source count
rates can be found in
this memo (pdf).