{'fraction_non_alphanumeric': 0.02244165170556553, 'fraction_numerical': 0.00718132854578097, 'mean_word_length': 4.930851063829787, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Analysis and modeling of anomalous scattering in the AXAF HETGS

Tests of the High-Energy Transmission Grating Spectrometer (HETGS) for the Advanced X-Ray Astrophysics Facility (AXAF) showed anomalous scattering of monochromatic radiation. The grating resolving power (E/dE) is of the order 1000, but test designed to search for small-angle scattering by the gratings showed events with significant deviations from the dispersed grating orders and concentrated along the dispersion direction. In this paper, we present a general overview of grating scatter as a result of fluctuations in the grating bar geometry. The grating scatter observed at the AXAF-X-Ray Calibration Facility is shown to be consistent with what one expects from scatter due to deviations in the grating bar geometry form perfect bars. For the purposes of modeling, a rectangular bar mode is adopted and bar parameters are deduced via fitting the model to the scattering data. The correlations deduce from this model lead to a simple physical picture of grating bar fluctuations where a small fraction of the bars, e.g., 1 in 200 are leaning.