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تسجيل مستخدم جديدTiming calibration of the APOLLO experiment
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The Apache Point Observatory Lunar Laser-ranging Operation (APOLLO) began millimeter-precision ranging to the Moon in 2006. Until now, a comprehensive validation of APOLLO system range accuracy has not been possible because of centimeter-scale deficiencies in computational models of the Earth-Moon range, and because APOLLO lacked an internal timing calibration system. Here, we report on the development of a system that enables in-situ calibration of the timing response of the APOLLO apparatus, simultaneous with lunar range measurements. The system was installed in August 2016. Preliminary results show that the APOLLO system can provide lunar range measurements with millimeter accuracy.
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Lunar laser ranging provides a number of leading experimental tests of gravitation -- important in our quest to unify General Relativity and the Standard Model of physics. The Apache Point Observatory Lunar Laser-ranging Operation (APOLLO) has for ye
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