On the stability of the open-string QED neutron and dark matter

Abstract

We study the stability of a hypothetical QED neutron, which consists of a colorsinglet system of two d quarks and a u quark interacting with the quantum electrodynamical (QED) interactions. As a quark cannot be isolated, the intrinsic motion of the three quarks in the lowest-energy state of the QED neutron may lie predominantly in 1+1 dimensions, as in a d-u-d open string. In such an open string, the attractive d-u and u-d QED interactions may overcome the weaker repulsive d-d QED interaction to bind the three quarks together. We examine the stability of the QED neutron in a phenomenological three-body model in 1+1 dimensions with an effective interaction between electric charges extracted from Schwinger's exact QED solution in 1+1 dimensions. The phenomenological model in a variational calculation yields a stable QED neutron with a mass of 44.5 MeV. The analogous QED proton with two u quarks and a d quark has been found to be too repulsive to be stable and does not have a bound or continuum state, onto which the QED neutron can decay via the weak interaction. Consequently, the QED neutron may be stable against the weak decay and may have a very long lifetime. Such a particle may occur at the deconfinementto-confinement phase transition of the quark-gluon plasma and may be a signature of the deconfinement-to-confinement transition of the quark gluon plasma in high-energy heavyion collisions. Because of its long lifetime, self-gravitating QED neutron assemblies (and similarly QED antineutron assemblies) of various sizes may be good candidates for a part of the primordial dark matter produced during the deconfinement-to-confinement phase transition of the quark gluon plasma in the evolution of the early Universe. 1 with the US Department of Energy (DOE). The US government retains and the publisher, by accepting the article for publication, acknowledges that the US government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this manuscript, or allow others to do so, for US government purposes. DOE will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan (http://energy.gov/downloads/doe-public-access-plan)

Dynamics of quarks and gauge fields in the lowest-energy states in QCD and QED

“…The predicted mass of the isoscalar I(J π ) = 0(0 − ) QED meson is close to the X17 mass of about 17 MeV subsequent observed [47][48][49][50]. Later observation of the E38 particles [51][52][53] lends additional tentative support to the possible occurrence of these q q QED meson composite particles [2,3,5,[44][45][46]. While the anomalous soft photon measurements as e + e − excesses have been well established experimentally, the X17 particle and the E38 particle needs further experimental confirmations.…”

“…According to the Schwinger's mass-(coupling constant) relation, the QED interaction, upon a comparison with the QCD interaction, will bring the quantized mass of a q q pair to the lower mass range of the anomalous soft photons. It was therefore proposed in [2,3,5,[44][45][46] that a quark and an antiquark in a q q system interacting with the QED interaction may lead to new open string bound states (QEDmeson states) with a mass of many tens of MeV. These QED mesons may be produced simultaneously with the QCD mesons in high-energy collisions [35][36][37][38][39][40][41][42][43], and the excess e + e − pairs may arise from the decays of these QED mesons.…”

Shedding light on X17: community report

“…, where R T ∼ 0.4 fm [150] and the longitudinal length L z ∼ 7.15 fm as estimated from Table 2 for the lowest QED mesons state in Ref. [151]. For the X17 with a mass of 17 MeV, Γ (X17 → γ γ ) ∼ 0.4 MeV.…”

“…Many different interpretations have been presented and their theoretical implications discussed [98]. We focus our attention on the description of the X17 particle and other anomalous particles as composite particles of a light quark and a light antiquark bound and confined by their mutual QED interaction [149][150][151][152][153]. We shall call such a composite particle a QED meson (compactly written as a "qedmeson"), in analogy with the QCD meson.…”