At wavelengths λ > 2 μ m, JWST obtains diffraction-limited imaging with a Strehl ratio = 0.8 and point spread function (PSF) FWHM of ~ λ / D radians (JWST's D = 6.5 m mirror). The NIRCam detectors achieve Nyquist sampling or better (FWHM > 2 pixels) above 2 µm in the short wavelength (SW) channel (0.6–2.3 µm) and above 4 µm in the long ...

The Space Telescope PSF (STPSF) package produces simulated point spread functions for JWST based on measured or budgeted optical path difference (OPD) files comprising wavefront errors in the Optical Telescope Element (OTE) and instruments. STPSF provides: Support for all of JWST's instruments.

We present a discussion of the methods that can be used to model the JWST Point Spread Function (PSF) and illustrate some of the potential impacts of the PSF properties on the scientific performance of the telescope. We summarize the quantitative PSF measurements typically used in astronomical imaging and evaluate those quantities on

function (PSF) at wavelengths longer than 2 microns. The JWST PSF quality and stability are intimately tied to the science capabilities as it is convolved with the astrophysical scene. However, the PSF evolves at a variety of timescales based on telescope jitter and thermal distortion as the observatory attitude is varied.

We present a detailed analysis of the point-spread function (PSF) of JWST NIRCam imaging in eight filters: F070W, F115W, F150W, F200W, F277W, F356W, F444W, and F480M, using publicly available data. Spatial variations in the PSF FWHM generally decrease with wavelength: the maximum and rms fractional variations are ∼20% and 5% in F070W, reduced ...

2023年8月27日 · In this paper, we introduce a hybrid PSF construction method called HybPSF for JWST NIRCam imaging data. HybPSF combines the WebbPSF software, which simulates the PSF for JWST, with observed data to produce more accurate and reliable PSF models.

2023年4月26日 · We present a detailed analysis of the point spread function (PSF) of JWST NIRCam imaging in eight filters: F070W, F115W, F150W, F200W, F277W, F356W, F444W, and F480M, using publicly available data.

Simulated JWST MIRI imaging point spread functions (PSFs) in each filter and predicted values for the full width at half maximum (FWHM), radial profiles, and encircled energy curves can be found using STPSF (formerly WebbPSF).

JWST users can access archived wavefront maps and utilize STScI tools to visualize and trend JWST wavefront error, and to create high-fidelity modeled Point Spread Functions (PSFs) corresponding to measured wavefronts at particular points in time.

This notebook demonstrates such a PSF subtraction as as example for making PSF simulations matched to a particular science observation. To make simulated PSFs a closer match to data “right out of the box”, STPSF as of release 1.2 includes simplified models to add significant detector effects into simulated PSFs for NIRCam, NIRISS, and MIRI.