Neil Ashby
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PARCS: a Primary Atomic Reference Clock in Space
2003
https://doi.org/10.1109/FREQ.1999.840728visibility
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7 pages
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Abstract
NET, in collaboration with the Jet Propulsion Laboratories (JPL), the University of Colorado, Politecnico di Torino and Harvard Smithsonian Center for Astrophysics (SAO) is building a laser-cooled cesium (Cs) atomic clock for flight on the Intemational Space Station (ISS). The clock, named PARCS (Primary Atomic Reference Clock in Space) takes advantage of the microgravity environment of the ISS to achieve a high stability of ,.(e) 5 x 10-'4*-"2 and an ultimate accuracy of 5 x 1 O-", more than an order of magnitude better than terrestrial Cs fountains. Additionally, this accurate clock on the ISS will be used to perform a variety of tests of fundamental physics, such as relativity theory. Since the ISS orbit will cover a large portion of the earth, PARCS will serve as an internationally accessible primary standard thus improving comparisons between intemational standards laboratories. Here we describe the scientific objectives of the PARCS mission, present our design considerations and laboratory studies of prototypes of clock components, and evaluate the anticipated performance of PARCS such as systematic shifts and the ultimate accuracy of the device. * Contribution of the US Government. Not subject to US copyright.
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