New experimental limits on the Pauli forbidden transitions in ${}^{12}$C nuclei obtained with 485 days Borexino data

The Pauli exclusion principle (PEP) has been tested for nucleons ($n,p$) in ${}^{12}C$ with the Borexino detector.The approach consists of a search for $\gamma$, $n$, $p$ and ${\beta }^{\pm }$ emitted in a non-Paulian transition of 1$P_{3\mathrm{/}2}$- shell nucleons to the filled 1$S_{1\mathrm{/}2}$ shell in nuclei. Due to the extremely low background and the large mass (278 t) of the Borexino detector, the following most stringent up-to-date experimental bounds on PEP violating transitions of nucleons have been established: $\tau ({}^{12}\mathrm{C}\to {}^{12}\tilde{\mathrm{C}}+\gamma )\ge 5.0\cdot {10}^{31}$ y, $\tau ({}^{12}\mathrm{C}\to {}^{11}\tilde{\mathrm{B}}+p)\ge 8.9\cdot {10}^{29}$ y, $\tau ({}^{12}\mathrm{C}\to {}^{11}\tilde{\mathrm{C}}+n)\ge 3.4\cdot {10}^{30}$ y, $\tau({^{12}\rm{C}}\to{^{12}\widetilde{\rm{N}}}+ e^- + \widetilde{\nu_e}) \geq 3.1\cdot 10^{30}$yand$\tau({^{12}\rm{C}}\to{^{12}\widetilde{\rm{B}}}+ e^+ + \nu_e) \geq 2.1 \cdot 10^{30}$ y, all at 90% C.L. The corresponding upper limits on the relative strengths for the searched non-Paulian electromagnetic, strong and weak transitions have been estimated: $\delta^2_{\gamma} \leq 2.2\cdot10^{-57}$,$\delta^2_{N} \leq 4.1\cdot10^{-60}$and$\delta^2_{\beta} \leq 2.1\cdot10^{-35}$.