Discussion items

Simulated Data
  • Deadline is May 31st
  • Need Level1b data
  • "Small" data sets in all TSO modes (simple, noise free)
  • "Medium" data set containing simulated transit with realistic uncertainties
  • "Large" data set for memory management and archival distribution purposes
  • Need matching APT files
  • See below for PDF of required header keywords
  • Place files on central storage
    • /grp/jwst/dms/TSO

  • Everett presented update on NIRCam simulated data (see slides below)
 Bright Target Acquisition (TA) 
  • NIRCam TA uses medium filter (F335M) and NGROUPS=3
  • Saturation limit is K=7.02
  • 4 GTO targets exceed this limit (HD 189733, HD 209458, HD 149026, GJ 436)
  • Implementation of a narrow filter for TA improves limit by ~2.5 mag, but won't likely be possible until Cycle 2
  • Option A: TA on offset target
    • Positive: Requires no additional capabilities
    • Negative: Limited to < 30" separation, requires both positions be know very precisely, faintness limits
  • Option B: TA on saturated target
    • Positive: No offset uncertainty, better pointing consistency, doesn't require nearby offset star
    • Negative: May require changes to flag saturated pixels
    • John Stansberry to test how far into saturation we can reasonably go
    • Faint offset targets aren't an issue, K=18.5 using DEEP8 and NGROUPS=65
  • Option C: Add TA through a narrow-band filter to APT and OSS
    • Positive: Improves saturation limit to ~K=5.5
    • Negatives:
      • Requires changes to APT, PPSDB, OPGS, OSS
      • May require separate 'apertures' to be defined for TA in the 2 filters (calibration issue).
  • Option D: Allow TA using NGROUPS=1, 2
    • Positive: Improves saturation limit by ~1.2 mag
    • Negative: Requires bigger changes to OSS than Option C, and APT changes (at least).
SystemOffset Distance (")Offset Jmag
HD 18973311.510.1
HD 20945832.915.7
HD 14902620.413.9
GJ 43626.416.4

Proposal Instructions for JWST
  • Waiver for exposure limit on MIRI TSO imaging
  • Implement new Special Requirement "Time Series Observation" for some JWST templates
  • Sarah Kendrew working on table of TSO modes (mandatory, optional, not available), may include in JDox

JWST Documentation
  • Many JDox pages are going live tomorrow (May 19th)
  • Instrument team members should review relevant pages and supply feedback if changes are needed
  • Still working on TSO landing page that provides a broad overview and directs users to additional pages for more detailed information

Best NIRISS Observing PracticesLoic
  • Loic recommends using F277 filter to measure position of first order trace (without second order overlap)
  • Filter/grism combination not currently supported in APT for science observations
  • Loïc Albert to look into prioritizing this change with respect to other tasks


Action items