Measurement of the branching fractions of the singly Cabibbo-suppressed decays ${\mathrm{\Lambda }}_c^{+}\to p\eta$ and ${\mathrm{\Lambda }}_c^{+}\to p\omega$

Based on 4.5 \mbox{fb^{-1}} $e^{+}{e}^{-}$ collision data collected with BESIII detector at seven energy points between 4.600 and 4.699 GeV, the branching fractions for ${\mathrm{\Lambda }}_c^{+}\to p\eta$ and ${\mathrm{\Lambda }}_c^{+}\to p\omega$ were measured by means of single-tag method. The branching fractions of ${\mathrm{\Lambda }}_c^{+}\to p\eta$ and ${\mathrm{\Lambda }}_c^{+}\to p\omega$ are determined to be $(1.57\pm {0.11}_{\mathrm{s}\mathrm{t}\mathrm{a}\mathrm{t}}\pm {0.04}_{\mathrm{s}\mathrm{y}\mathrm{s}\mathrm{t}})\times {10}^{-3}$ and $(1.11\pm {0.20}_{\mathrm{s}\mathrm{t}\mathrm{a}\mathrm{t}}\pm {0.07}_{\mathrm{s}\mathrm{y}\mathrm{s}\mathrm{t}})\times {10}^{-3}$, with a statistical significance of greater than 10 $\sigma$ and 5.7 $\sigma$, respectively. These results are consistent with the previous measurements by BESIII, LHCb and Belle, and the result of ${\mathrm{\Lambda }}_c^{+}\to p\eta$ is the most precise to date.