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A beam channel of polarized protons and antiprotons produced from decays of $\mathrm{\Lambda }$- and anti-$\mathrm{\Lambda }$-hyperons for the SPASCHARM experiment is to be built at IHEP U-70 accelerator in Protvino, Russia. The methods for tagging and measuring polarization of the beam (anti)protons are discussed in this report. The fast on-line beam tagging exploits the correlations between polarization and kinematics of (anti)protons originated from (anti)$\mathrm{\Lambda }$-decays. In the intermediate focus of primary target, decay (anti)protons of different transverse polarizations are spatially dispersed transversely with respect to the beam axis. The tagging system, consisting of fast beam detectors with good spatial resolution, measures the momentum and trajectory of each beam particle, including its position at the intermediate focus, thus allowing instant (on-line) assignment of the transverse polarization value to each (anti)proton. This system is also extremely useful for the beam channel tuning. While being fast and convenient, the polarization tagging fully relies on computing of particle transportation in the beam channel. In order to verify the real beam polarization and operating of the tagging system and beam channel, the independent absolute beam polarimetry is to be used. It is based on measuring the spin asymmetries in elastic scattering of beam (anti)protons in Coulomb-Nuclear Interference (CNI) and diffractive kinematic regions. It is estimated that less than one week of data taking would allow measuring an absolute beam polarization at the statistical accuracy of $\sim$4–5%.

A new experiment SPASCHARM for systematic study of polarization phenomena in the inclusive and exclusive hadronic reactions in the energy range of IHEP accelerator U-70 (12–50GeV) is currently under development. The universal experimental setup will detect dozens of various resonances and stable particles produced in collisions of unpolarized beams with the polarized target, and at the next stage, using polarized proton and antiproton beams. At the beginning, the final states consisting of light quarks ($u$, $d$, $s$) will be reconstructed, and later on the charmonium states will be studied. Measurements are planned for a variety of beams: ${\pi }^{\pm },K^{\pm },p$, antiprotons. Hyperon polarization and spin density matrix elements of the vector mesons will be measured along with the single-spin asymmetry (SSA). The 2$\pi$-acceptance in azimuth, which is extremely useful for reduction of systematic errors in measurements of spin observables, will be implemented in the experiment. The solid angle acceptance of the setup, $\mathrm{\Delta }\theta \approx 250$ mrad vertically and 350 mrad horizontally in the beam fragmentation region, covers a wide range of kinematic variables $p_T$ and $x_F$. This provides the opportunity for separating dependences on these two variables which is usually not possible in the setups with a small solid angle acceptance. Unlike some previous polarization experiments, the SPASCHARM will be able to simultaneously accumulate and record data on the both, charged and neutral particle production.

In 2014 BESIII collected a data sample of 567 $p{b}^{-1}$ at $E_{cm}$ = 4.6 GeV, which is just above the ${\mathrm{\Lambda }}_c^{+}$ pair production threshold. By analyzing this data sample, we have measured the absolute branching fractions for many decays of ${\mathrm{\Lambda }}_c^{+}$ for the first time. These decays include the semileptonic decays of $\mathrm{\Lambda }{e}^{+}\nu$, $\mathrm{\Lambda }{\mu }^{+}\nu$, the hadronic decays of $p{K}_s$, $p{K}^{-}{\pi }^{+}$, $p{K}^{-}{\pi }^{+}{\pi }^0$, $\mathrm{\Lambda }{\pi }^{+}$, $\mathrm{\Lambda }{\pi }^{+}{\pi }^0$, ${\mathrm{\Sigma }}^{+}{\pi }^{+}{\pi }^0$, $p{K}_s{\pi }^0$, $\mathrm{\Lambda }{\pi }^{+}{\pi }^{+}{\pi }^{-}$, $p{K}_s{\pi }^{+}{\pi }^{-}$, ${\mathrm{\Sigma }}^0{\pi }^{+}$, ${\mathrm{\Sigma }}^{+}{\pi }^0$, ${\mathrm{\Sigma }}^{+}\omega$, $p\varphi$, $p{K}^{+}{K}^{-}(\mathrm{\text{non}}-\varphi )$, $p{\pi }^{+}{\pi }^{-}$, $n{K}_s\pi +$, ${\mathrm{\Sigma }}^{-}{\pi }^{+}{\pi }^{+}({\pi }^0)$ and inclusive decay $\mathrm{\Lambda }$ + anything. The decays of $p{\pi }^{+}{\pi }^{-}$, $n{K}_s{\pi }^{+}$ and ${\mathrm{\Sigma }}^{-}{\pi }^{+}{\pi }^{+}{\pi }^0$ are observed for the first time and the others are measured with significantly improved precision. These results are important to benefit the development of the related theories, and provide important inputs for both charmed baryons and $B$ physics.