cesium beam for cesium beam atomic clock
Date: circa 1960
Inventory Number: RS1502b
Classification: Clock
Subject:
Maker: National Company, Inc. (1914 - 1970s)
User: Robert Vessot
User: Norman Foster Ramsey Jr. (1915 - 2011)
User: Smithsonian Astrophysical Observatory (founded 1890)
Maker: Harvard College Observatory (founded 1839)
Cultural Region:
Place of Origin:
Dimensions:
203 x 16 x 22 cm (79 15/16 x 6 5/16 x 8 11/16 in.)
Material:
Accessories: Screws.
Description:
Long pipe in which enters several electronic devices along its path.
In Collection(s)
Signedon plate, stamped: MANUFACTURED BY NATIONAL CO. INC. / MALDEN, MASS.
FunctionThis is the central element of the cesium beam atomic clock. Working in a high vacuum, a stream of cesium-133 atoms produced by an oven would run along the tube and the atoms in the required quantum states would be selected magnetically in several stages. The selected ones would be put in resonance with a microwave signal and their emissions, of a very specific frequency, analyzed by the clock.
For more information on cesium beam atomic clocks, see A Brief History of Atomic Clocks at the NIST website.
For more information on cesium beam atomic clocks, see A Brief History of Atomic Clocks at the NIST website.
Historical AttributesStarting in the 1960s, Robert Vessot, at the Smithsonian Astrophysical Observatory, together with seveal colleagues including Norman Ramsey, the creator of the Maser, developed the atomic clock based on it. This is one of the atomic clocks that resulted from that process.
For more details of this development and its use in the verification of Einstein's General Relativity Theory, see Published References.
For more details of this development and its use in the verification of Einstein's General Relativity Theory, see Published References.
Curatorial RemarksFor a large collection of atomic clocks and a detailed history, see the following website.
ProvenanceFrom Dr. Robert Vessot's laboratory at the Center for Astrophysics, Harvard University.