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Overview

November 2009: Following its alignment to the HST OTA, IR point spread function measurements of ~130 stars over the field were made in the F098M, F105W and F160W and compared to model computations and CEI specifications. Deep, core-saturated images of a standard star, sampling the field at 5 locations, were also obtained to evaluate the PSF wings. All encircled energy specifications are met or exceeded, with exception of the inner core EE at 160 nm, as expected from previous ground testing and modeling results. The optical model has been correlated to the observed PSF properties and may be used to predict performance over the full IR spectral range.

For more details, see ISR 2009-37.

IR Encircled Energy Tables

 

WFC3/IR PSF Encircled Energy Fraction vs. Aperture Radius (arcsec)

Filter

Pivot (Å) 0.13″ 0.15″ 0.26″ 0.39″ 0.45″ 0.52″ 0.65″ 0.78″ 0.91″ 1.0″ 1.2″ 1.3″ 2.0″ 2.6″ 3.2″ 3.9″ 4.5″ 5.2″ 6.0″
F098M 9865 0.596 0.656 0.818 0.857 0.872 0.887 0.905 0.922 0.934 0.943 0.949 0.956 0.974 0.979 0.983 0.987 0.991 0.995 1
F105W 10551 0.577 0.634 0.811 0.852 0.867 0.882 0.901 0.917 0.929 0.939 0.946 0.953 0.973 0.978 0.982 0.986 0.990 0.995 1
F110W 11534 0.553 0.606 0.797 0.845 0.859 0.873 0.895 0.909 0.922 0.933 0.941 0.948 0.970 0.976 0.980 0.985 0.990 0.994 1
F125W 12486 0.535 0.586 0.789 0.841 0.853 0.867 0.890 0.904 0.918 0.929 0.937 0.945 0.969 0.975 0.979 0.984 0.989 0.994 1
F126N 12585 0.534 0.584 0.789 0.840 0.852 0.867 0.890 0.904 0.917 0.929 0.937 0.944 0.969 0.975 0.980 0.984 0.989 0.994 1
F127M 12740 0.531 0.580 0.787 0.840 0.851 0.865 0.890 0.903 0.916 0.929 0.936 0.944 0.968 0.974 0.979 0.984 0.989 0.994 1
F128N 12832 0.529 0.579 0.786 0.839 0.851 0.865 0.889 0.902 0.916 0.928 0.936 0.943 0.968 0.974 0.979 0.984 0.989 0.994 1
F130N 13006 0.526 0.575 0.784 0.838 0.850 0.863 0.888 0.901 0.915 0.927 0.935 0.942 0.968 0.974 0.979 0.984 0.989 0.994 1
F132N 13188 0.523 0.572 0.780 0.838 0.849 0.862 0.887 0.900 0.914 0.926 0.934 0.942 0.967 0.973 0.978 0.984 0.989 0.994 1
F139M 13838 0.513 0.561 0.769 0.836 0.846 0.858 0.882 0.898 0.912 0.923 0.931 0.939 0.966 0.972 0.978 0.983 0.988 0.993 1
F140W 13923 0.512 0.562 0.764 0.837 0.848 0.860 0.882 0.900 0.912 0.923 0.931 0.940 0.967 0.974 0.979 0.984 0.989 0.994 1
F153M 15322 0.496 0.546 0.740 0.835 0.846 0.856 0.876 0.899 0.909 0.918 0.927 0.937 0.967 0.974 0.979 0.984 0.989 0.994 1
F160W 15369 0.494 0.545 0.736 0.833 0.844 0.855 0.875 0.897 0.908 0.918 0.926 0.935 0.966 0.972 0.978 0.983 0.988 0.994 1
F164N 16404 0.483 0.536 0.713 0.829 0.842 0.852 0.870 0.894 0.905 0.914 0.923 0.932 0.963 0.970 0.976 0.982 0.987 0.993 1
F167N 16642 0.480 0.534 0.706 0.828 0.841 0.851 0.869 0.893 0.904 0.913 0.922 0.931 0.962 0.970 0.975 0.981 0.987 0.993 1

 

 

Last Updated: 06/02/2023

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