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Theta Term in QCD sum rules at Finite Temperature and the Neutron Electric Dipole Moment

Mohamed Chabab
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Abstract

By using thermal QCD sum rules to investigate the $\barθ$ induced neutron electric dipole moment $d_n$, we have examined the behaviour of broken CP symmetry at finite temperature. We find that, below the critical temperature, the ratio $\mid {d_n \over \barθ}\mid$ slightly decreases but survives at temperature effects, implying T nonrestoration of CP-invariance \cite{Chabab}.

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Mohamed Chabab. 2002-12-11. Theta Term in QCD sum rules at Finite Temperature and the Neutron Electric Dipole Moment. https://doi.org/10.1063/1.1570569

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