Galaxy formation and evolution

Abstract:

We summarize JWST's measured telescope performance across science Cycle 1. The stability of segments alignments is typically better than 10 nanometers RMS between measurements every two days, leading to highly stable point spread functions. The frequency of segment "tilt events" decreased significantly, and larger tilt events ceased entirely, as structures gradually equilibrated after cooldown. Mirror corrections every 1-2 months now maintain the telescope below 70 nm RMS wavefront error. Observed micrometeoroid impacts during cycle 1 had negligible effect on science performance, consistent with preflight predictions. As JWST begins Cycle 2, its optical performance and stability are equal to, and in some ways better than, the performance reported at the end of commissioning.Comment: STScI Technical Memo. 2.5 pages text, 1 figur

Abstract:

In the published article, the prefactor in Equation (3) was incorrectly written as 3.3 × 104 as opposed to 3.3 × 105. The correct equation should be. This was a typo and did not propagate into or affect any quantitative results of the paper.