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Giampieri, Giacomo

Publications and source records attributed to Giampieri, Giacomo.

Measurement of the PPN Parameter (gamma) with radio signals from the Cassini Spacecraft at X- and Ka-Bands

Radio Doppler data from the Cassini spacecraft during its solar conjunction in June 2002 can be used to measure the bending of light by solar gravitation. In terms of the standard post-Newtonian parameter (gamma), we find that (gamma) - 1 = (-1.3 +/- 5.2)x10^-5 in agreement with the theory of General Relativity. This result implies that the parameter (omega) in the Brans-Dicke theory is greater than 9000 at a 95% confidence level.

radio science↗

Algorithms for Unequal-Arm Michelson Interferometers

A method of data acquisition and data analysis is described in which the performance of Michelson-type interferometers with unequal arms can be made nearly the same as interferometers with equal arms. The method requires a separate readout of the relative phase in each arm, made by interfering the returning beam in each arm with a fraction of the outgoing beam.

Michelson Interferometer↗