A sign of three-nucleon short-range correlation from an analysis of nuclear mass and short-range correlation probability

Three-nucleon short-range correlation ($3N$ SRC) represents a rare and intriguing part of the nuclear dynamics at short distance, beyond the two-nucleon short-range correlation ($2N$ SRC). To search its existence is a hot topic in the ongoing and future high-energy nuclear experiments and the developments of nuclear theory. In this study, we found a positive sign of $3N$ SRC in nuclei, by analyzing the correlation between the per-nucleon nuclear mass and the probability of a nucleon in $2N$ SRC state, with the current experimental measurements of $^2$H, $^3$He, $^4$He, $^9$Be, $^{12}$C, $^{27}$Al, $^{56}$Fe, Cu, $^{197}$Au and $^{208}$Pb from SLAC, CLAS, and JLab Hall C collaborations. The effective masses of the nucleons in $2N$ SRC and $3N$ SRC are also extracted from the analysis, which provide some references for the nuclear medium effect study. The probability of $3N$ SRC is much smaller than that of $2N$ SRC, thus requiring high-luminosity experiments to confirm its existence.