Quark-level analogue of nuclear fusion with doubly-heavy baryons

Abstract

The recent discovery by LHCb of the first doubly-charmed baryon ${\Xi }_{cc}^{++}=ccu$ at $3621.40\pm 0.78$ MeV implies a large binding energy $\sim 130$ MeV between the two $c$ quarks. This strong binding enables a quark-rearrangement exothermic reaction ${\Lambda }_c{\Lambda }_c\to {\Xi }_{cc}^{++}n$ with $Q=12$ MeV, which is a quark-level analogue of deuterium-tritium nuclear fusion reaction $DT\to {}^4\mathrm{He}n$. Due to much larger binding energy between two $b$ quarks $\sim 280$ MeV, the analogous reaction with $b$ quarks, ${\Lambda }_b{\Lambda }_b\to {\Xi }_{bb}N$ is expected to have a dramatically larger $Q$-value, $138\pm 12$ MeV.

Comments: 5 pages, 1 figure