Time-reversal violation experiment

Cold, trapped radioactive atoms open up new experimental opportunities in nuclear physics. Trapped radioactive atoms can be used in experiments on the fundamental symmetries, including experiments on nuclear / -decay, atomic parity nonconservation, and the search for parity-violating and time-reversal-violating electric dipole moments. The first successful experiments on the trapping of radioactive atoms were performed with the isotope Na (Lu et al. 1994). It is expected that further activity in this direction will be concentrated on efforts to undertake meaningful measurements with trapped radioactive species. 

T-violation experiment The effect of time-reversal (7) violation on the transition of photons through a system of magnetized foils that have a Mossbauer transition with comparable M and E2 strength (such as in Ru or Au)... 

After the discovery of the combined charge and space symmetry violation, or CP violation, in the decay of neutral mesons [2], the search for the EDMs of elementary particles has become one of the fundamental problems in physics. A permanent EDM is induced by the super-weak interactions that violate both space inversion symmetry and time reversal invariance [11], Considerable experimental efforts have been invested in probing for atomic EDMs (da) induced by EDMs of the proton, neutron, and electron, and by the P,T-odd interactions between them. The best available limit for the electron EDM, de, was obtained from atomic T1 experiments [12], which established an upper limit of de < 1.6 x 10 27e-cm. The benchmark upper limit on a nuclear EDM is obtained from the atomic EDM experiment on Iyt,Hg [13] as d ig < 2.1 x 10 2 e-cm, from which the best restriction on the proton EDM, dp < 5.4 x 10 24e-cm, was also obtained by Dmitriev and Senkov [14]. The previous upper limit on the proton EDM was estimated from the molecular T1F experiments by Hinds and co-workers [15]. 

As mentioned earlier, heavy polar diatomic molecules, such as BaF, YbF, T1F, and PbO, are the prime experimental probes for the search of the violation of space inversion symmetry (P) and time reversal invariance (T). The experimental detection of these effects has important consequences [37, 38] for the theory of fundamental interactions or for physics beyond the standard model [39, 40]. For instance, a series of experiments on T1F [41] have already been reported, which provide the tightest limit available on the tensor coupling constant Cj, proton electric dipole moment (EDM) dp, and so on. Experiments on the YbF and BaF molecules are also of fundamental significance for the study of symmetry violation in nature, as these experiments have the potential to detect effects due to the electron EDM de. Accurate theoretical calculations are also absolutely necessary to interpret these ongoing (and perhaps forthcoming) experimental outcomes. For example, knowledge of the effective electric field E (characterized by Wd) on the unpaired electron is required to link the experimentally determined P,T-odd frequency shift with the electron s EDM de in the ground (X2X /2) state of YbF and BaF. 

The multipole mixing ratio S of mixed M1+E2 radiation (d = IE2/M1I) as well as the phase angle between E2 and Ml components can be obtained from the relative areas of the corresponding peaks (Kistner 1968 Wagner et al. 1968 Atac et al. 1968). The value of the phase angle has a relevance in testing the time reversal in electromagnetic interaction. No violation of time reversal was found in Mossbauer experiments (Kalvius et al. 1968 Mullen 1986). 

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