6533b7dbfe1ef96bd1270a54
RESEARCH PRODUCT
The two-photon decay of X(6900) from light-by-light scattering at the LHC
Volodymyr BiloshytskyiVladimir PascalutsaLucian Harland-langBogdan MalaescuKristof SchmiedenMatthias Schottsubject
[PHYS.NUCL] Physics [physics]/Nuclear Theory [nucl-th]interpretation of experiments: CERN LHC Coll[PHYS.HEXP] Physics [physics]/High Energy Physics - Experiment [hep-ex]Nuclear Theoryradiative decayphoton photon: scatteringinterpretation of experiments: LHC-BFOS: Physical sciencestetraquarkvector mesonHigh Energy Physics - Experimentmass spectrum[PHYS.HPHE] Physics [physics]/High Energy Physics - Phenomenology [hep-ph]Nuclear Theory (nucl-th)High Energy Physics - Experiment (hep-ex)High Energy Physics - PhenomenologyHigh Energy Physics - Phenomenology (hep-ph)branching ratiostructurephoton: pair productiontwo-photondescription
The LHCb Collaboration has recently discovered a structure around 6.9 GeV in the double-$J/\psi$ mass distribution, possibly a first fully-charmed tetraquark state $X(6900)$. Based on vector-meson dominance (VMD) such a state should have a significant branching ratio for decaying into two photons. We show that the recorded LHC data for the light-by-light scattering may indeed accommodate for such a state, with a $\gamma \gamma$ branching ratio of order of $10^{-4}$, which is larger even than the value inferred by the VMD. The spin-parity assignment $0^{-+}$ is in better agreement with the VMD prediction than $0^{++}$, albeit not significantly at the current precision. Further light-by-light scattering data in this region, clarifying the nature of this state, should be obtained in the Run 3 and probably in the high-luminosity phase of the LHC (Run 4 etc.).
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2022-07-27 |