arXiv subjects
Publications and source records attributed to V. L. Rykov.
The design and parameters of the polarized-beam facility at U-70 proton synchrotron of NRC Kurchatov Institute - IHEP are presented. The new beamline 24A will provide the polarized proton and antiproton beams for carrying out the rich physics program of the SPASCHARM experiment for comprehensive studies of spin phenomena in a wide spectrum of hadronic reactions in the energy range of 10-45 GeV.
The only comparative study of the inclusive pion single-spin asymmetries produced in the interactions of the polarized protons and antiprotons in collisions with unpolarized proton was carried out at E-704 experiment. Significant asymmetries were found at large $x_{F}$ and middle $p_{T}$, $π^{+}$ and $π^{0}$ asymmetries have positive signs while $π^{-}$ has negative one in the $p^{\uparrow}+p$ collisions, while in the $\bar{p}^{\uparrow}+p$ interactions the $π^{-}$ and $π^{0}$ asymmetries have positive signs while $π^{+}$ has negative sign. Similar experimental study can be done in the SPASCHARM experiment at U-70 accelerator at IHEP for various secondary particles with the use of 16 GeV polarized proton and antiproton beams.
The analysis\cite{ohkuma:1} of helicity transfer to $Λ_{c}^{+}$ in polarized proton collisions is extended to the proton helicity correlations with the $Λ_{c}^{+}$ transverse polarization in the production plane (parameter $D_{LS}$). The available spin transfer observables for the collisions of {\em two} longitudinally polarized protons are evaluated. It is shown that, in the central region at $Λ_{c}^{+}$ transverse momenta of a few GeV/c, $D_{LS}$ parameters are of about the same size as the helicity-to-helicity correlations. The methodical issue of using spin transfers for cross-checks of systematic errors in cross-section $A_{LL}$ measurements at polarized proton colliders is also briefly discussed.
The track timing capabilities of a silicon drift detector based tracker for a future linear electron-positron collider are evaluated. We show such a detector can time tracks at the nanosecond, and for high-$P_{T}$, sub-nanosecond level. This implies that, even for collider designs with the bunch spacing at 1.4 ns, every track can be assigned to a particular bunch crossing at a confidence level of up to two standard deviations. We suggest a choice for the drift axes in the tracker layers to simultaneously optimize the momentum resolution and track timing.
The procedure for the STAR Barrel Electromagnetic Calorimeter (BEMC) absolute calibrations, using penetrating charged particle hits (MIP-hits) from physics events at RHIC, is presented. Its systematic and statistical errors are evaluated. It is shown that, using this technique, the equalization and transfer of the absolute scale from the test beam can be done to a percent level accuracy in a reasonable amount of time for the entire STAR BEMC. MIP-hits would also be an effective tool for continuously monitoring the variations of the BEMC tower's gains, virtually without interference to STAR's main physics program. The method does not rely on simulations for anything other than geometric and some other small corrections, and also for estimations of the systematic errors. It directly transfers measured test beam responses to operations at RHIC.
The capabilities of RHIC with polarized protons to test the Lorentz structure of electroweak interactions and also the properties of MSSM Higgs, should it be discovered, are discussed.
Just in months ahead, the first high luminosity collisions of two polarized proton beams are expected to occur at RHIC in BNL at sqrt{s} up to 500 GeV, bringing a new quality to the collider physics. In collisions of polarized particles, the presence of two axial vectors of initial polarizations, fully controlled by experimenters, may dramatically increase the number of available for tests correlations between participating vectors, generating asymmetries that could relatively easily be measured. In frame of Standard Model (SM), many of these asymmetries are either strongly suppressed or strictly prohibited. Therefore, if some of them were found nonzero, this could be an indication of a new physics beyond SM. If certain criteria met, it might be difficult to explain the observed nonzero correlations in theories without CP- and/or T-violation.