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Title: A measurement of the gravitational acceleration of the antiproton

Conference ·
OSTI ID:6966155

A fundamental experiment in gravity proposed by us, is the measurement of the gravitational force on antimatter. This measurement would constitute the first direct test of the Weak Equivalence Principle (WEP) for antimatter. The availability of low-energy antiprotons at CERN has made such an experiment feasible, and a proposal to carry out such a measurement has been accepted by the CERN Program Committee. We plan to use a time-of-flight technique similar to that pioneered by Fairbank and Witteborn in their measurement of the gravitational force on an electron. Very slow particles are launched into a vertical drift tube and the time-of-flight spectrum of these particles is recorded. This spectrum will exhibit a cut-off point directly related to the gravitational acceleration of the particles. Obtaining very slow antiprotons involves several stages of deceleration. Antiprotons from LEAR will be initially decelerated from 2 MeV to tens of kilovolts by passing them through a thin foil. After capture and cooling in a series of ion traps, the antiprotons will be in a thermal distribution with a temperature of a few degrees Kelvin. These ultra-cold antiprotons will then be released a few at a time into the drift tube. A detector will measure the arrival time of the particles at the exit of the drift tube. H{sup {minus}}-ion, which have almost identical electromagnetic properties to the antiprotons, will be used for comparison and as a calibration standard. 7 refs., 1 fig.

Research Organization:
Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
Sponsoring Organization:
DOE/MA
DOE Contract Number:
W-7405-ENG-36
OSTI ID:
6966155
Report Number(s):
LA-UR-90-1014; CONF-900183-3; CONF-900766-2; ON: DE90008903; TRN: 90-010736
Resource Relation:
Conference: Recontres De Moriond '90: new and exotic phenomena; 1. biennial conference on low energy antiproton physics, Les Arcs (France); Stockholm (Sweden), 20-27 Jan 1990; 2-6 Jul 1990
Country of Publication:
United States
Language:
English