Policy for Target of Opportunity and Transient observations

PFS is now accepting three types of ToO programs (as of S27A):

Non-rapid ToO: The field is not defined in advance.
Deadline for target list submission: By 9 am HST one day before the requested night.
Response from the observatory might be delayed during weekends and holiday season. A maximum of two iteration can be possible if PIs can respond flexibly.
Rapid ToO: The field is not defined in advance.
Deadline for target list submission: By 9 am HST on the day of the requested night.
The PI has to inform the observatory about their intent to propose this mode before their proposal submission. Note that this option is not guaranteed to be executed. Response from the observatory might be delayed during weekends and holiday season. A maximum of one iteration can be possible if PIs can respond flexibly.
Transient: Time-allocated follow-up of survey-identified transients
Field and PPP deadline: the same as the deadline for each CfP of the normal program.
Target list deadline: 1 week before the allocation night.

For rapid ToO, the PI must inform the observatory about their intent to propose such an observation before proposal submission.
The uploaded target list should contain information about the expected target properties. This is important for the observatory to evaluate technical feasibility.

The uploaded target list should contain information about the expected target properties. This is important for the observatory to evaluate technical feasibility.
The ETC result is critically important to estimate time allocation.
The PI should clearly state their requested allocation dates.

The PI must include the Upload ID in the triggering email, which means they have to finish uploading the completed target list before triggering.
The target list cannot be changed after triggering because there is no time for planning.
For unknown brigthness targets, the PI should input a dummy value (NaN) for the targets' brightness column.
Brightness should be AB > 16 mag in all arms.

The PI must follow the triggering procedure described in the Procedures for Target of Opportunity Observations.
Additionally to the their triggering phone call to the Director, the PI MUST send an email to
This is mandatory! If any step in the triggering procedure is skipped, the trigger may be rejected.
The triggering email must contain all of the following:
- Proposal ID and the PI's name
- Requested triggering time in HST
- Target List (Upload) ID
- Preferred PA
- Pointing centers
- Request for planning and strategy for observations (if nothing, please write none)
The observatory will check the triggering information and decide whether to accept or reject it.
Once the trigger is accepted, a PFS operation member will begin planning using the submitted target list without contacting the PIs.
Once planning is finished, a PFS operation member will contact the PI to review the planning results.
The PIs can request some modifications if time allows. A maxiumum of two iterations is accepted for non-rapid ToOs, and one iteration for rapid ToOs.
A PFS operation member may contact the PI during planning if the target list has critical issues, but it means delaying preparation. Therefore, the PI should make sure that their submitted target lists follows the guidelines.
The PI or designated observers are required to attend the observation.

If accepted, transient proposals will be allocated as Classical mode observations.
The observatory will contact the PI at least two weeks before the allocated night.
The PI must upload the target list one week before the allocated night using the Target Uploader and inform the PSF observation helpdesk about the uploadID.
A maximum of two iterations is accepted for transient observations.