{'fraction_non_alphanumeric': 0.05125148986889154, 'fraction_numerical': 0.05601907032181168, 'mean_word_length': 4.7534246575342465, '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}}
Elastic scattering of pions from 3H and 3He into the backward hemisphere.

We have measured differential cross sections for the elastic scattering of charged pions from 3H and 3He into the backward hemisphere. Near the peak of the delta resonance, at Tπ=180 MeV, an angular distribution covering 114° to 168° in the laboratory extends our earlier measurements. At Tπ=142, 180, 220, and 256 MeV, we have measured an excitation function at angles approaching 170°. The cross sections for the reactions 3He(π+,π+)3He and 3H(π−,π−)3H show a rise at back angles which is not seen for 3He(π−,π−)3He and 3H(π+,π+)3H. There is a dip in the cross sections near 130°, for Tπ=180 MeV. We also present the values of the charge symmetric ratios r1 and r2, which cross each other near 120° and maintain this new relationship in the backwards hemisphere.