Dátum: 2023. szeptember 7.

*Recent observations of anomalous angular correlations of electron-positron pairs in several nuclear reactions have indicated the existence of a hypothetical neutral boson of rest mass ~17 MeV/c^2, called the X17 particle [1, 1b, 1c]. A similar idea may help in interpreting the other set of experiments on photon pair spectra around the invariant mass ~38 MeV/c^2, by assuming the existence of the so-called E38 particle [2]. Besides a fifth force explanation of the ATOMKI nuclear anomalies [3], the QED meson theory due to Wong [4, 4b] may reproduce quite well the above-mentioned invariant masses.*

*In the present talk we base our considerations on the exact solutions of the Dirac equation of the system „charged particle + a quantized electromagnetic plane wave”, which has long been used in the quantum description of high-harmonic generation in mutiphoton Compton scattering [5, 5b]. We will show that these non-perturbative solutions, applied to the proton, lead to a mass term for the dressed radiation with the value (rest mass)c^2 = 17.0087 MeV [5c]. This may perhaps be identified with the X17 vector boson resonace, found by the ATOMKI scientists in several experiments [1, 1b, 1c]. A similar considerations with the udd quarks of the neutron yields the value (rest mass)c^2 = 37.9938 MeV, which may correspond to the hypotetical E38 particle [2]. We emphasize that, besides the Sommerfeld fine structure constant and the proton (neutron) mass, our derived formulas contain merely some statistical factors, so they do not contain any adjustable parameters, like e.g. the flux tube radius in Wong’s formalism [4b]. One of the motivations for giving the present talk has been to illustrate the synergy of applying non-perturbative strong-field and quantum optics methods, for possible interpretations of some particle physics phenomena, being in the frontiers of recent interests.*

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*References:*

*[1] Krasznahorkay A J, Csatlós M, Csige L, Gácsi Z, Gulyás J, Hunyadi M, Kuti I, Nyakó B M, Stuhl L, Timár J, Tornyi T G, Vajta Zs, Ketel T J and Krasznahorkay A, Observation of anomalous internal pair creation in 8Be : a possible indication of a light, neutral boson. Phys. Rev. Lett. 116, 042501 (2016). [1b] Krasznahorkay A J, et al., New anomaly observed in 12C supports the existence and the vector character of the hypothetical X17 boson. Phys. Rev. C 106, L061601 (2022). [1c] Krasznahorkay A J, Krasznahorkay A, Csatlós M, Csige L and Timár J, A new particle is being born in ATOMKI that could make a connection to dark matter. Nucl. Phys. News 32 (2), 10-15 (2022).*

*[2] Abraamyan K, Austin C, Baznat M, Gudima K, Kozhin M, Reznikov S and Sorin A, Check of the structure in photon pairs spectra at the invariant mass of about 38 MeV/c^2. EJP Web of Conferences 204, 08004 (2019).*

*[3] Feng J L, Tait T M P and Verhaaren Ch B, Dynamical evidence for a fifth force explanation of the ATOMKI nuclear anomalies. Phys. Rev. D 102, 036016 (2020).*

*[4] Wong Ch-Y, Open string QED meson decription of the X17 particle and dark matter. JHEP08, 165 (2022). [4b] Wong Ch-Y, QED meson description of the anomalous particles and the X17 particle. ISMD 2023 - 52nd Intl. Symp. on Multiparticle Dynamics, Aug 21-25 2023 - Gyöngyös, Hungary. https://indico.cern.ch/event/1258038/timetable/#20230822.detailed*

*[5] Varró S, Theoretical study of the interaction of free electrons with intense light. (Ph.D. dissertation, 1981). Hung. Phys. Journal XXXI, 399-454 (1983). [5b] Bergou J and Varró S, Nonlinear scattering processes in the presence of a quantised radiation field: II. Relativistic treatment. J. Phys. A: Math. Gen. 14, 2281-2303 (1981). [5c] Varró S, Proposal for an electromagnetic mass formula for the X17 particle. Talk presented at ISMD 2023 - 52nd Intl. Symp. on Multiparticle Dynamics, August 21-25 2023 - Gyöngyös, Hungary. https://indico.cern.ch/event/1258038/timetable/#20230825.detailed*