{'fraction_non_alphanumeric': 0.024, 'fraction_numerical': 0.008, 'mean_word_length': 5.586466165413534, '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}}
Optical fiber systems for the BigBOSS instrument

We describe the fiber optics systems for use in BigBOSS, a proposed massively parallel multi-object spectrograph for the Kitt Peak Mayall 4-m telescope that will measure baryon acoustic oscillations to explore dark energy. BigBOSS will include 5,000 optical fibers each precisely actuator-positioned to collect an astronomical target’s flux at the telescope prime-focus. The fibers are to be routed 40m through the telescope facility to feed ten visible-band imaging spectrographs. We report on our fiber component development and performance measurement program. Results include the numerical modeling of focal ratio degradation (FRD), observations of actual fibers’ collimated and converging beam FRD, and observations of FRD from different types of fiber terminations, mechanical connectors, and fusion-splice connections.