E.11 The Cycle 24 Calibration Plan

The Cycle 24 calibration plan was executed from November 2016 through October 2017. The individual programs are listed in Table E.12 and are described in more detail on the WFC3 Calibration Plan webpage. In the Cycle 24 Calibration section, a similar table contains direct links to the Phase II programs and observation dates. This information may alternately be accessed via the HST Program Information webpage by entering the Proposal ID.

The WFC3 Cycle 24 section also links to a PDF presentation summarizing WFC3 usage and comparing the Cycle 24 plan with the prior cycle. This document contains more details on the calibration justification and in many cases includes supporting figures with the latest results from regular monitoring.

The Cycle 24 calibration plan was designed to:

• maintain and update the standard reference files (biases, darks, linearity, CTE traps, UVIS anomalous QE pixels, post-flash)
• monitor the health of the instrument (throughput, gain, hysteresis, bad/hot pixels, sink pixels, CTE decline, stability of the post-flash LED, filter transmission, wavelength and flux stability of grisms, number of IR blobs, state of the CSM)
• test the precision of the IR count rate non-linearity correction for faint targets and determine whether a wavelength-dependent correction is required
• improve the precision of the UVIS contamination monitor by making use of spatially scanned observations of photometric standards
• re-evaluate the 2013 UVIS pixel-based CTE model and verify that the recommended post-flash level has not changed

The results of these calibration programs will be documented in Instrument Science Reports on the WFC3 website at:
http://www.stsci.edu/hst/wfc3/documents/ISRs/

Table E.12: Cycle 24 Calibration Programs

¹New programs this cycle; others are routine monitors.