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P. E. Budkovsky

Publications and source records attributed to P. E. Budkovsky.

6 recordsLinked to original sources

EPECUR setup for the search of narrow baryon resonances in the pion-proton scattering

EPECUR experimental setup is aimed at the search of narrow resonant states by precision measurement of differential and total reaction cross sections of pion-nucleon interaction with 1 MeV pion energy steps. In five years passed from the idea of the experiment till the start of the data taking in April of 2009, a new apparatus was build from scratch at the universal beam line 322 of ITEP proton synchrotron U-10. The setup is essentially a non-magnetic spectrometer with a liquid hydrogen target based on the large aperture drift chambers with hexagonal structure. The unique properties of the beam line allow individual pion momentum measurement with the accuracy better than 0.1%. The momentum tagging is done with 1 mm pitch proportional chambers located in the first focus of the beam line. The design of numerous subsystems of the setup is based on modern electronic components including microprocessors and FPGA. All the subsystems are tuned and tested both individually and as parts of the whole working setup. The distributed data acquisition system uses widely spread USB and Ethernet protocols, which allows to achieve high performance and take full advantage of the industrial solutions.

physics.ins-det

Backward asymmetry measurements in the elastic pion-proton scattering at resonance energies

The asymmetry parameter P was measured for the elastic pion-proton scattering in the very backward angular region of theta_cm ~ 150-170^o at several pion beam energies in the invariant mass range containing most of the pion-proton resonances. The general goal of the experimental program was to provide new data for partial wave analyses in order to resolve their uncertainties in the baryon resonance region to allow the unambiguous baryon spectrum reconstructions. Until recently the parameter P was not measured in the examined domain that might be explained by the extremely low cross section. At the same time the predictions of various partial wave analyses are far from agreement in some kinematic areas and specifically those areas were chosen for the measurements where the disagreement is most pronouncing. The experiment was performed at the ITEP U-10 proton synchrotron, Moscow, by the ITEP-PNPI collaboration in the latest 5 years.

hep-ex

Cost Effective Electronics for Proportional and Drift Chambers of 'EPECUR' Experiment

'EPECUR' experiment setup is under construction at the beam line 322 of the ITEP proton synchrotron. The experiment requires several large area drift chambers to provide reasonable acceptance and fine pitch proportional chambers for beam particle tracking with total number of electronic channels of about 7000. New compact and cost effective readout system for these gaseous detectors was designed, prototyped and tested in the latest two years based on the modern technologies in analog and digital electronics, as well as in data transfer protocols. Mass production of the proportional chamber electronics is close to the end, while the boards for the drift chambers are manufactured in the amount to equip one 8-plane module. The paper presents the functional description of the whole DAQ system and its main parts together with some of the test results as an illustration of the excellent performance of the system. The appendix contains specific information which may be useful for the system users or code developers.

physics.ins-det

Measurements of spin rotation parameter A in pion-proton elastic scattering at 1.62 GeV/c

The ITEP-PNPI collaboration presents the results of the measurements of the spin rotation parameter A in the elastic scattering of positive and negative pions on protons at P_beam = 1.62 GeV/c. The setup included a longitudinally-polarized proton target with superconductive magnet, multiwire spark chambers and a carbon polarimeter with thick filter. Results are compared to the predictions of partial wave analyses. The experiment was performed at the ITEP proton synchrotron, Moscow.

hep-ex

Study of the reaction pi- p --> pi- pi+ n on the polarized proton target at 1.78 GeV/c. Experiment and amplitude analysis

We present the results of the experimental study of the reaction of dipion production by the beam of the negative pions with momentum 1.78 GeV/c on the polarized proton and liquid hydrogen targets. The experiment covers the region of dipion masses near the mass of rho-meson and small momenta transferred |t|<0.2(GeV/c)^2. The whole set of spin density matrix elements was reconstructed and model-independent and model-dependent amplitude analyses of the reaction were performed. The experiment allows to exclude the ambiguity of the amplitude analysis existing at high energies. The results contain evidences in favour of existing of narrow sigma(750). The data also allows to estimate intercept of a_1-meson Regge trajectory. The experiment was performed at the ITEP proton synchrotron, Moscow.

hep-ph