Using APT for Large and Treasury Programs in Phase I

Introduction

For all Large (>100 orbits) and Treasury programs (excluding those with solar system and generic targets), we ask proposers to include additional technical detail on the scheduling aspects of their program. This information is useful to both proposers (so they can devise observations that can be successfully scheduled) and to STScI (so we can identify and resolve conflicts early, thus allowing for data to be obtained as quickly as possible). You should also read the User Information Report on http://www.stsci.edu/hst/HST_overview/documents/uir/UIR_Large.pdf for an overview of scheduling issues.

Note that this is the first cycle for which we are requesting this information, and it is possible that revisions and/or clarifications to these instructions or http://www.stsci.edu/hst/HST_overview/documents/uir/UIR_Large.pdf may be necessary. In order to allow us to contact all potential Large or Treasury Program proposers with updated submission information, we request that you send a message to help@stsci.edu notifying us that you are planning a Large or Treasury program as soon as possible. You should of course also send a message to help@stsci.edu if you have any questions about these instructions or the UIR.

Instructions

Below are step-by-step instructions for analyzing the schedulability of your program.

In order to maximize the schedulability of Large Programs, we now request proposers to use the Orbit Visibility table below, rather than that in the HST Primer (Table 6.1). Note that the values in this table are shorter (by ~6 minutes) than those in the Primer (which represent more typical schedulabilities). During implementation in Phase II, we will work with those approved PIs to provide the maximum visibility possible consistent with an efficient schedule.


                Orbit Visibilty Table
              
Target      Declination   SHD or CVZ   Visibility    LOW visibility
             (degrees)     Sp. Req.      (min)           (min)
--------------------------------------------------------------------
Moving      Object near      no            51              48
          ecliptic plane
Fixed          0-18          no            51              47
Fixed         18-43          no            51              48
Fixed         43-58          no            51              45
Fixed         58-60          no            51              46
Fixed         60-63          no            52              46
Fixed         63-68          no            52              45
Fixed         68-73          no            52              43
Fixed         73-75          no            52              42
Fixed         75-85          no            53              42
Fixed         85-88          no            54              42
Fixed         88-90          no            54              41
Any            Any           SHD           25         incompatible
Any        Any CVZ Dec       CVZ           96         incompatible

The target visibility plot from http://www.stsci.edu/hst/proposing/LargePrograms will show you the nominal visibility as a function of date. If you need to use a longer visibility period than listed above, please justify the need for the longer time, and use the reduced total schedulability when determining the schedulability statistics requested below.

If you require a specific, fixed Orientation (e.g. you are placing a slit along the axis of a galaxy), then use the Orientation plots available on http://www.stsci.edu/hst/proposing/LargePrograms to estimate the approximate number of days the observation is schedulable at that Orientation. Check the scheduling impact of providing the broadest possible (within scientific contraints) orientation range for your observation.
If you require a non-specific, fixed Orientation (e.g. you are mosaicking a large field, and the orientation is strictly to align the tiles), then use the Orientation plots to estimate the optimal Orientations (e.g. for a mosaic, +90, +180, and +270 may be acceptable) that provide the maximum schedulability.
In APT, select Large Program on Proposal Information page (just under "Proposal PDF Attachment").
On the Observation page, fill in the relevant scheduling requirements (on PRIME observations only; observations with the CPAR flag set do not need the scheduling requirements set) from the following:
- SAME ORIENT: setting this requirements means that all exposures defined in the Observation Block MUST be observed at the exact same ORIENT. This requirement is only meaningful if the observations are to occur in multiple visits (e.g. Number of Iterations is greater than 1, or if the Total Orbits are greater than 5).
- ORIENT: enter the ORIENT range that the all exposures defined in the Observation Block MUST be observed within. If multiple ORIENT ranges are acceptable, then enter all values.
- BETWEEN: enter the range of dates that all exposures defined in the Observation Block MUST be observed within. If multiple BETWEENs are acceptable, then enter all values.
- AFTER OBSERVATION BY: enter any timing requirements between Observation Blocks. Timing requirements between observations WITHIN an Observation Block do not need to be specified.
- Note that the CVZ, Shadow, and Low Sky flags also affect schedulability.
After entering any scheduling requirements, select the Visit Planner from the main Toolbar (with the Observation of interest selected in the Hierarchical (Tree) editor). After initialization, press the Update Display button to process the observation. Ignore the warning (yellow triangle) that you get on the visit (which says the results are just an estimate...this is fine for Phase I). Note that if you link visits with the AFTER OBSERVATION BY, then selecting any one of those visits will cause the Visit Planner to process all visits together (since all visits impact the total schedulability).
The Visit Planner will display the Total Visibility for the Observation Block. A green check means the observation is schedulable at some time during the year, while the red x means the observation is NOT schedulable at any time. You can examine the details (e.g. Target Visibility, Absolute Orient Visibility, etc.) by clicking on the key to the left of the green check/red x.
If the Observation Block is schedulable, placing the cursor on the black areas in the timeline will provide a tooltip with the exact dates that are available. Note that the display shows several years of schedulability. You should just note the schedulability during Cycle 13 (July 1 2004 through June 30 2005).
If the Observation is not schedulable, then examination of the details will reveal which scheduling requirements are inconsistent (e.g. the absolute ORIENT conflicts with the target visibility). Revise the scheduling requirements to make the observation schedulable, or in some rare cases, you may need to select a different target (if possible).
If any changes have been made to the scheduling requirements, press the Update Display button to get an updated timeline.
Include a text description of the schedulability of your observations in the Observation Description of your PDF attachment. This description should include:
- number and duration of the schedulability window
- scheduling constraints (e.g. ORIENTs), including flexibility (e.g. ORIENT ranges)
- number of orbits per day = total request/available days
- value and justification of target visibility used (if different from the table above)

NOTE: When you submit, you will get a warning saying the proposal has errors. If there are no red X's in your proposal, then the warning is about the Visit Planner error (see step 5 above). Put a note in the type-in box saying "Visit Planner error" and submit.