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Showing papers by "T. J. Sloan published in 2019"


Journal ArticleDOI
TL;DR: In this article, experimental searches for deviations in the two photon spectra from the decay of the neutral pion in the process $\phi \rightarrow \pi+} \pi^{+}
Abstract: Standards calculations by the Fermi's Golden rule involve approximations. These approximations could lead to deviations from the predictions of the standard model as discussed in another paper. In this paper we propose experimental searches for such deviations in the two photon spectra from the decay of the neutral pion in the process $\phi \rightarrow \pi^{+} \pi^{-} \pi^{0}$ and in the annihilation of the positron from nclear $\beta$ decay.

4 citations


Journal ArticleDOI
TL;DR: In this paper, the authors describe an experimental test of the predictions of this theoretical work by searching for events with two photons from positron annihilation of energy larger than the electron rest mass.
Abstract: In the positron-electron annihilation process, finite deviations from the standard calculation based on the Fermi's Golden rule are suggested in recent theoretical work. This paper describes an experimental test of the predictions of this theoretical work by searching for events with two photons from positron annihilation of energy larger than the electron rest mass ($511\,{\rm keV}$). The positrons came from a ${\rm {}^{22}Na}$ source, tagging the third photon from the spontaneous emission of ${\rm {}^{22}{Ne}^*}$ de-exitation to suppress backgrounds. Using the collected sample of $1.06\times 10^{7}$ positron-electron annihilations, triple coincidence photon events in the signal enhanced energy regions are examined. The observed number of events in two signal regions, $N^{\rm SR1}_{\rm obs}=0$ and $N^{\rm SR2}_{\rm obs}=0$ are, within a current precision, consistent with the expected number of events, $N^{\rm SR1}_{\rm exp}=0.86\pm0.08({\rm stat.})^{+1.85}_{-0.81}({\rm syst.})$ and $N^{\rm SR2}_{\rm exp}=0.37\pm 0.05({\rm stat.})^{+0.80}_{-0.29}({\rm syst.})$ from Fermi's golden rule respectively. Based on the $P^{(d)}$ modeling, the 90% CL lower limit on the photon wave packet size is obtained.

2 citations