NuSTAR GO Target of Opportunity (ToO) trigger or

Directors Discretionary Time (DDT) observation request

NuSTAR ToO and DDT observation requests will in general not be considered for events or sources that could have been predicted and proposed for in General Observer (GO) programs. NuSTAR DDT requests with a response time of <48 hours will not be considered because the rapid response capability is reserved for ToO proposals selected in GO programs. This restriction is being adopted as a result of guidance from NASA's 2019 Senior Review.

In particular, requests for observations of the following types of sources and events require special justification describing why the requested observation type could not have been proposed as a GO target:

  • Known or candidate black hole systems
  • Known or candidate pulsar or magnetar systems
  • Candidate counterparts of gravitational wave or astrophysical neutrino detections
  • Nova or Supernova events
  • Luminosity variations from known or candidate AGN (including blazars and Tidal Disruption Events)
  • Observations of the Sun or other Solar system objects
  • Observations of events with specific time constraints
  • Observations coordinated with other observatories that could have been proposed for to joint GO programs
As a specific example, binary systems where periastron intervals are known can be proposed to the GO program, with observations triggered from monitoring of activity by other observatories. Observations that are simultaneous with ground or space based activities can also be proposed to the GO program, even if the exact dates for the coordinated observations are not known at the time of the proposal.

We encourage the community to propose to the various peer reviewed GO programs for NuSTAR ToO observations. Observations of all selected GO ToO observations automatically have the highest priority for scheduling.

Please review the NuSTAR schedules for details of upcoming observations and the table of approved ToO programs from the NuSTAR GO program
and joint GO programs with Chandra, XMM-Newton, IXPE, XRISM, and the Neil Gehrels Swift Observatory.

Principal requester
Name:
Institute:
Primary Email Address:
  additional email addresses may be supplied in the Other Remarks section below
Best way to reach me:
24 hour Contact Information:
especially phone numbers in case of questions from the operations team for rapid response triggers
Scientific Justification
Object type:
Triggering an approved GO program:
  if "No" then this is a DDT request		 If "Yes", then please supply the mission name and GO proposal number
GO proposal #:
Scientific Justification:

  Not required for approved NuSTAR or joint GO ToO proposals

  For DDT requests please review the information at the top of this page
  and emphasize why the observation could not have been proposed to a GO program

Please limit to 2000 characters.
Relevant URLs: one per line
Justification for this particular target: Please limit to 1000 characters.
Likelihood of detection, duration,
and recurrence of transient behavior: 		Please limit to 400 characters.
Response time requested:
    Response times < 48 hours are reserved for GO programs
    or unique astrophysical transients (e.g. Local Group Supernovae)
The majority of approved non-GO DDTs have response times >48 hours to 1 week.
Justification for requested response time: Please limit to 1000 characters.
Target details
Target Name
RA    (J2000 decimal degrees from 0.0 to 360.0)
Dec   (J2000 decimal degrees from -90.0 to 90.0)
from until

  Date/time format options are described here. Default is UTC, unless you specify another time zone.

Observing time (kiloseconds)
  Note that the majority of approved DDT observations have exposure times of 40 ksec or less 		kiloseconds
Minimum 20 ksec
Justification for observing time
  Give details of any source modeling, particularly for exposure time requests above 40 ksec 		Please limit to 1000 characters.
Expected NuSTAR count rate
  Predicted instrument count rate for both modules using 50% PSF extraction with no dead time 		counts / sec, both telescopes combined, not including background

HEASARC WebPIMMS simulator is available here (set "Into:" field to "NUSTAR")

Maximum expected NuSTAR count rate
  in case of flaring, bursts, etc. 		counts / sec, both telescopes combined, not including background
Approximate expected spectrum
e.g. absorbed power-law with photon index 1.7-2.0
Source morphology
Coordination with other observatories?

   Provide the observatory name(s) and the following details if available:
  • Are you planning on submitting a request?
  • Have observations already been approved?
    • Give proposal number and selection category (A,B,C etc.)
    • or request ID number
  • Have the observations been scheduled?
    • provide any observation timing information
 		Please limit to 1000 characters.
Other Remarks Please limit to 1000 characters.


Clicking the "Submit!" button sends emails and text messages to the NuSTAR operations team. A confirmation email will be automatically sent to the address provided in the 'Email:' field above.

GO ToO triggers have the highest priority and will be scheduled within the requested response time.

DDT requests will be reviewed by the NuSTAR PI and the operations team and you will be contacted with a decision to approve or decline the request. NuSTAR data associated with approved DDT requests will have no exclusive use period and, when completed, will be available via the public NuSTAR archive. See NuSTAR HEASARC archive for more information.

A minimal set of data products for ToO and DDT observations performed within the last 14 days is also available, and updated as each observation progresses, via the NuSTAR quicklook products webpage. Please carefully read the caveats on the use of this data detailed on the quicklook ToO products webpage.

Please contact   nustar-help at srl.caltech.edu   if you have any questions.