The inclusive differential cross sections for the production of
and
mesons, protons, and antiprotons with momenta between 6 and 50 GeV/
c
and nuclear fragments of mass number
in the momentum range ...between 20 and 220 GeV/
c
were measured in carbon–lead collisions at a beam kinetic energy of 19.6 GeV per nucleon (
GeV). A comparison with the respective cross sections for carbon–carbon interactions is performed, and the dependence on the target mass number (
) is estimated. The present analysis shows that the observed particles originate predominantly from peripheral interactions.
The invariant cross sections for forward charged-hadron production at zero angle in carbon–carbon collisions at a beam kinetic energy of 19.6 GeV per nucleon were measured at the U-70 accelerator in ...an experiment performed with the aid of a combined spectrometer including beam line 22 and detectors of the modified FODS setup. The beam line rigidity was varied between 7 and 70 GeV/
. The results are compared with the predictions of the FTFP model and a self-similar solution for nucleus–nucleus collisions.
The inclusive differential cross sections for forward production of nuclear fragments at an angle of 0∘ in CC collisions at beam energy 20.5 GeV/nucleon (SNN=6.3GeV) are presented. Measurements have ...been performed at the U-70 Accelerator Complex (Protvino) using a combined spectrometer on base of the beamline. Fragments selection was carried out by measuring of ionization in scintillation counters taking into account the data from threshold Cherenkov counters and hadron calorimeter. Fragment mass was determined through Cherenkov light emission angle measured in the spectrometer of ring imaging Cherenkov radiation. Data are given for fragments with charge 1≤Z≤6, atomic number 1≤A≤10 and A/Z<3.4 with momenta from 20 to 210 GeV/c. The measurements are compared with Fritiof model, statistical models and theoretical parameterizations. The discovered differences between theory and experiment are discussed.
The polarized proton and antiproton beam project at U-70 accelerator Abramov, V.V.; Azhgirey, I.L.; Garkusha, V.I. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
09/2018, Letnik:
901
Journal Article
Recenzirano
Odprti dostop
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 design and parameters of the polarized-beam facility at U-70 proton synchrotron of IHEP, Protvino, are presented. The polarized proton and antiproton beam line 24A is currently under development ...at IHEP. It will serve as a main playground for carrying out the rich program of the SPASCHARM experiment for comprehensive studies of spin phenomena in a wide variety of hadronic reactions in the beam energy range of ∼10-45 GeV.
The new SPASCHARM experiment for systematic studies of polarization phenomena in strong interactions is under construction now at IHEP, Protvino. The technical beam runs for the experiment first ...stage are planned for the Fall 2016 and Spring 2017. At this stage, the polarization measurements will be carried out with unpolarized hadronic beams of various compositions (π±, K±, p, antiprotons), using the polarized target. The universal large acceptance experimental set-up is capable detecting and identification most charged and neutral particles and reconstructing a large number of resonances produced in beam interactions at polarized proton target, and later on at the second stage, in collisions of polarized proton and antiproton beams with fixed targets of various materials. The large acceptance and wide data acquisition bandwidth would provide the capabilities for simultaneous data accumulation for a number of physics analyses from the measurements of single-spin asymmetries in inclusive and exclusive reactions to reconstructions of final state hyperon polarizations and spin density matrix elements for vector mesons in a wide range of kinematic variables (pT, xF).
We describe the absolute polarimeters for the beam channel intended to transport polarized proton and antiproton beam at U70 accelerator. The circulating proton beam of 60 GeV/c and intensity 1013 ...p/cycle is slowly extracted from accelerator. It strakes the external an aluminum target of one interaction length. The emitted on forward direction Λ and Λ¯ hyperons by parity violating process serve as the source of the polarized protons and antiprotons. In this case we expect to get the polarized antiproton beams in the momentum range 10-40 GeV/c with intensity, approximately 104 - 4x105 antiprotons/cycle, 106 protons/cycle.
Polarimeters for the SPASCHARM Experiment Semenov, P. A; Bogdanov, A. A; Bukreeva, S. I ...
International journal of modern physics. Conference series,
2016, Letnik:
40, Številka:
1
Journal Article
Recenzirano
Odprti dostop
A beam channel of polarized protons and antiprotons produced from decays of
Λ
- and anti-
Λ
-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)
Λ
-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
∼
4–5%.
The absolute polarimeter based on the elastic p̄p-scattering in the diffraction kinematic regions with the total momentum transfer squared coverage of 0.1 < − t < 0.3 (GeV c)2 is proposed for the ...polarized antiproton beam at the U-70 proton synchrotron of IHEP. It is shown that it would take ∼200-400 hours for measuring the beam polarization at the statistical errors of ΔPB PB 10-15%. These time estimates include also the time which is necessary for the measurements of an analyzing power AN, using a polarized target. Besides the measurements of beam polarizations, the proposed polarimeter provides an opportunity for carrying out the experimental studies of the small momentum transfers physics which would be a valuable enrichment of the SPASCHARM experiment capabilities and its physics program.
The polarized proton and antiproton beam channel is currently under development at the U-70 accelerator of IHEP, Protvino, Russia. An availability of the both, polarized protons and antiprotons ...provides an exciting opportunity for the comparative studies of spin effects induced by polarized protons and antiprotons in a variety of hadronic reactions. While the proton and antiproton beams are formed by essentially the same method, there is the specific in the antiproton beam shaping and properties compared to protons. In this report, we address some technical details of forming the polarized antiproton beam and describe its main properties.
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