Antimatter Gravity Measurements with Cold Antihydrogen: the AEgIS Experiment

AbstractPostglacial rebound in Fennoscandia causes striking trends in gravity measurements of the area. We present time series of absolute gravity data collected between 1976 and 2019 on 12 stations in Finland with different types of instruments. First, we determine the trends at each station and analyse the effect of the instrument types. We estimate, for example, an offset of 6.8 μgal for the JILAg-5 instrument with respect to the FG5-type instruments. Applying the offsets in the trend analysis strengthens the trends being in good agreement with the NKG2016LU_gdot model of gravity change. Trends of seven stations were found robust and were used to analyse the stabilization of the trends in time and to determine the relationship between gravity change rates and land uplift rates as measured with global navigation satellite systems (GNSS) as well as from the NKG2016LU_abs land uplift model. Trends calculated from combined and offset-corrected measurements of JILAg-5- and FG5-type instruments stabilized in 15 to 20 years and at some stations even faster. The trends of FG5-type instrument data alone stabilized generally within 10 years. The ratio between gravity change rates and vertical rates from different data sets yields values between − 0.206 ± 0.017 and − 0.227 ± 0.024 µGal/mm and axis intercept values between 0.248 ± 0.089 and 0.335 ± 0.136 µGal/yr. These values are larger than previous estimates for Fennoscandia.

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Gravity measurements at sea, 1952 and 1953

Transactions American Geophysical Union ◽

10.1029/tr036i002p00326 ◽

1955 ◽

Vol 36 (2) ◽

pp. 326 ◽

Cited By ~ 8

Author(s):

J. Lamar Worzel ◽

G. Lynn Shurbet ◽

Maurice Ewing

Keyword(s):

Gravity Measurements

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Antimatter Free-Fall Experiments and Charge Asymmetry

Symmetry ◽

10.3390/sym13071192 ◽

2021 ◽

Vol 13 (7) ◽

pp. 1192

Author(s):

Ulrich David Jentschura

Keyword(s):

Field Theory ◽

Asymmetry Parameter ◽

Charge Asymmetry ◽

Free Fall ◽

Experimental Setup ◽

Charge Neutrality ◽

The Earth ◽

Antimatter Gravity ◽

Precision Test ◽

Theoretical Side

We propose a method by which one could use modified antimatter gravity experiments in order to perform a high-precision test of antimatter charge neutrality. The proposal is based on the application of a strong, external, vertically oriented electric field during an antimatter free-fall gravity experiment in the gravitational field of the Earth. The proposed experimental setup has the potential to drastically improve the limits on the charge-asymmetry parameter ϵ¯q of antimatter. On the theoretical side, we analyze possibilities to describe a putative charge-asymmetry of matter and antimatter, proportional to the parameters ϵq and ϵ¯q, by Lagrangian methods. We found that such an asymmetry could be described by four-dimensional Lorentz-invariant operators that break CPT without destroying the locality of the field theory. The mechanism involves an interaction Lagrangian with field operators decomposed into particle or antiparticle field contributions. Our Lagrangian is otherwise Lorentz, as well as PT invariant. Constraints to be derived on the parameter ϵ¯q do not depend on the assumed theoretical model.

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