1. A Preliminary Cycle 1 Calibration Plan for the JWST Science Instruments James Muzerolle

2. Timeline: Launch, ~6 months Commissioning checkout of mechanisms, early calibrations to enable science Commissioning activity requests (“CARs”) now written Cycle 1: science obs begin as instrument modes are commissioned – need full calibrations

3. Cycle 1 Calibration Plan Goals obtain all internal and celestial observations needed to fully calibrate the science instruments: characterization of detector effects not done or completed on the ground (spectro)photometric, astrometric calibration monitoring/stability of key metrics and effects that may change anything else not covered or completed during Commissioning begin defining a baseline plan by defining the set of likely programs and drafting program “summaries” use as input into the SODRM (Gordon et al.)

4. plan conceived and written by instrument leads: NIRCam: Anton Koekemoer NIRSpec: James Muzerolle NIRISS: Kevin Volk, Harry Ferguson MIRI: Karl Gordon status: all planned program summaries are complete - 39 programs among the 4 SIs - available at https://confluence.stsci.edu/display/JWST/Cycle+1+Calibrat ion+plans modified versions of all have been added to the SODRM

5. example program summary

6. grand total of 756 hours: 258 hrs likely to be done as parallels 82 hrs can be run during slews (internals) Plan statistics

7. the vast majority of data volume will be obtained in parallel observations (all darks) need to investigate at the visit level to verify within sufficient limits

8. data categories shared by most/all instruments most common are darks, flats, flux calibration many external observations share the same targets: astrometric calibration field, photometric standards

9. MIRI and NIRSpec dominate more modes, monitoring, and standard stars

10. more than half of the programs are monitors darks, lamp flats, (spectro)photometric calibration cadences mostly notional at this point

11. Deliverables dark reference files bad pixel maps read noise measurements P- and L-flat reference files Linearity reference files astrometric solution and distortion reference files PSF images/characterization persistence maps Spectral traces LSF characterization absolute photometric calibration conversion factors relative throughput measures

12. Future work The plan will be maintained by the new JWST Calibration & Commissioning Working Group check completeness of deliverables (Van Dixon reference file studies) push further coordination with the Commissioning plan  many monitoring programs based on CARs (internals, astrometric & photometric calibration)  better define the boundaries between Commissioning and Cycle 1 update programs as new ground test results are obtained plan ground-based preparatory observations (vetting of appropriate targets, etc)

13. - expect to phase in Cycle 1 over L+5 to L+6 months approximate commissioning timeline: L+ d L +