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Title: Antiprotons are another matter

Abstract

Theories of gravity abound, whereas experiments in gravity are few in number. An important experiment in gravity that has not been performed is the measurement of the gravitational acceleration of antimatter. Although there have been attempts to infer these properties from those of normal matter, none of these theoretical arguments are compelling. Modern theories of gravity that attempt to unify gravity with the other forces of nature predict that in principle antimatter can fall differently than normal matter in the Earth's field. Some of these supergravity theories predict that antimatter will fall faster, and that normal matter will fall with a small Baryon-number dependance in the earth's field. All of these predictions violate the Weak Equivalence Principle, a cornerstone of General Relativity, but are consistent with CPT conservation. In our approved experiment at LEAR (PS-200) we will test the Weak Equivalence Principle for antimatter by measuring the gravitational acceleration of the antiproton. Through a series of deceleration stages, antiprotons from LEAR will be lowered in energy to approx.4 Kelvin at which energy the gravitational effect will be measureable. The measurement will employ the time-of-flight technique wherein the antiprotons are released vertically in a drift tube. The spectrum of time-of-flight measurementsmore » can be used to extract the gravitational acceleration experienced by the particles. The system will be calibrated using H/sup -/ ions which simulates the electromagnetic behavior of the antiproton, yet is a baryon to approx.0.1%. To extract the gravitational acceleration of the antiproton relative to the H/sup -/ ion with a statistical precision of 1% will require the release of approx.10/sup 6/ to 10/sup 7/ particles.« less

Authors:
Publication Date:
Research Org.:
Los Alamos National Lab., NM (USA)
OSTI Identifier:
6232315
Report Number(s):
LA-UR-87-2386; CONF-8706176-2
ON: DE87013159
DOE Contract Number:  
W-7405-ENG-36
Resource Type:
Conference
Resource Relation:
Conference: Workshop and symposium on the physics of low energy, stored, and trapped particles, Stockholm, Sweden, 14 Jun 1987; Other Information: Portions of this document are illegible in microfiche products
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ANTIPROTONS; GRAVITATIONAL INTERACTIONS; ANALYTICAL SOLUTION; BOLTZMANN STATISTICS; CALIBRATION; EQUIVALENCE PRINCIPLE; GENERAL RELATIVITY THEORY; HYDROGEN IONS 1 MINUS; SUPERGRAVITY; TESTING; TIME-OF-FLIGHT METHOD; ANIONS; ANTIBARYONS; ANTIMATTER; ANTINUCLEI; ANTINUCLEONS; ANTIPARTICLES; BARYONS; BASIC INTERACTIONS; CHARGED PARTICLES; ELEMENTARY PARTICLES; FERMIONS; FIELD THEORIES; HADRONS; HYDROGEN IONS; INTERACTIONS; IONS; NUCLEI; NUCLEONS; UNIFIED-FIELD THEORIES; 657003* - Theoretical & Mathematical Physics- Relativity & Gravitation

Citation Formats

Hynes, M V. Antiprotons are another matter. United States: N. p., 1987. Web.
Hynes, M V. Antiprotons are another matter. United States.
Hynes, M V. Thu . "Antiprotons are another matter". United States. https://www.osti.gov/servlets/purl/6232315.
@article{osti_6232315,
title = {Antiprotons are another matter},
author = {Hynes, M V},
abstractNote = {Theories of gravity abound, whereas experiments in gravity are few in number. An important experiment in gravity that has not been performed is the measurement of the gravitational acceleration of antimatter. Although there have been attempts to infer these properties from those of normal matter, none of these theoretical arguments are compelling. Modern theories of gravity that attempt to unify gravity with the other forces of nature predict that in principle antimatter can fall differently than normal matter in the Earth's field. Some of these supergravity theories predict that antimatter will fall faster, and that normal matter will fall with a small Baryon-number dependance in the earth's field. All of these predictions violate the Weak Equivalence Principle, a cornerstone of General Relativity, but are consistent with CPT conservation. In our approved experiment at LEAR (PS-200) we will test the Weak Equivalence Principle for antimatter by measuring the gravitational acceleration of the antiproton. Through a series of deceleration stages, antiprotons from LEAR will be lowered in energy to approx.4 Kelvin at which energy the gravitational effect will be measureable. The measurement will employ the time-of-flight technique wherein the antiprotons are released vertically in a drift tube. The spectrum of time-of-flight measurements can be used to extract the gravitational acceleration experienced by the particles. The system will be calibrated using H/sup -/ ions which simulates the electromagnetic behavior of the antiproton, yet is a baryon to approx.0.1%. To extract the gravitational acceleration of the antiproton relative to the H/sup -/ ion with a statistical precision of 1% will require the release of approx.10/sup 6/ to 10/sup 7/ particles.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {1987},
month = {1}
}

Conference:
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