Observation of *

Journal article

Using data taken at 29 center-of-mass energies between 4.16 and 4.70 GeV with the BESIII detector at the Beijing Electron Positron Collider corresponding to a total integrated luminosity of approximately 18.8 $\rm fb^{-1}$, the process $e^+e^- \to p p \bar{p} \bar{n} \pi^{-} + c.c.$ is observed for the first time with a statistical significance of $11.5\sigma$. The average Born cross sections in the energy ranges of (4.160, 4.380) GeV, (4.400, 4.600) GeV and (4.610, 4.700) GeV are measured to be $(21.5\pm5.7\pm1.2)$ fb, $(46.3\pm10.6\pm2.5)$ fb and $(59.0\pm9.4\pm3.2)$ fb, respectively, where the first uncertainties are statistical and the second are systematic. The line shapes of the $\bar{p}\bar{n}$ and $pp\pi^-$ invariant mass spectra are consistent with phase space distributions, indicating that no hexaquark or di-baryon state is observed.Comment: 10 pages, 4 figures. Submitted to Chinese Physics

Authors: Ablikim, M; Achasov, MN; Adlarson, P; Albrecht, M; Aliberti, R

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: IOP Publishing
• Journal: Chinese Physics C
• Volume: 47
• Issue: 4
• Pages: 043001-043001
• Publication date: 2023-01-30
• DOI: 10.1088/1674-1137/acb6eb
• ISSN: 1674-1137
• Language: English