References - Bogoliubov Laboratory of Theoretical Physics - JINR

POLARIZATION TRANSFER MECHANISM AS A POSSIBLE SOURCE
OF THE POLARIZED ANTIPROTONS
M.A. Chetvertkov 1 † , V.A. Chetvertkova 2 and S.B. Nurushev 3
(1) Moscow State University, Moscow ,Russia
(2) Skobelitsyn Institute of nuclear physics, Moscow State University, Moscow, Russia
(3) Institute of high energy physics, Protvino, Russia
† E-mail: match1988@gmail.com
Abstract
We suggest to experimental study the polarization transfer mechanism in the
inclusive reaction of the antiproton production by the polarized proton beam.
Introduction
The problem of producing t he intense polarized antiproton source with the appropriate
polarization becomes very acute at present. Such interest is instigated by the great
potential of the physics with the polarized antiprotons [1]. Approximately a dozen suggestions
were made about how to get the polarized antiprotons [2], but none of them
(exclusion is the filtering technique [3]) was experimentally demonstrated as really working
tool. Therefore we suggest the experiment at AGS for measuring the spin transfer
tensor from the polarized protons to the secondary antiprotons produced at zero degree.
We recall the standard technique of obtaining the unpolarized antiprotons by the unpolarized
primary proton beam according to PS CERN scheme. Then we modify this scheme
to produce the polarized antiprotons by the polarized proton beam. We also propose the
schemes of measuring the spin transfer tensor at p production at zero angle as a function
of the antiproton momentum.
Experimental evidences for the polarization transfer
mechanism.
There is no any theoretical or experimental paper devoted to the direct prediction or
proof of the existence of the polarization transfer mechanism in the inclusive reaction
p ↑ +N → p ↑ +X, where the arrows indicate the polarization of the corresponding
particle. Let’s remind some other examples of the polarization transfer mechanism.
Neutron polarization by the spin transfer mechanism
Let’s consider the production of polarized neutrons from the inclusive reaction C(p, n)X
with 590 MeV protons [4]. If polarized protons are used a polarized neutron beam may
obtain. It was found that the transfer of polarization from longitudinally polarized protons
to the longitudinally polarized neutrons was most effective. The absolute neutron beam
intensity was about 10 8 n/s for integrated neutron flux over energy range from 100 to
590 MeV. Reaction p(→)+A = n(→)+X was used for production of the polarized neutrons
at zero degree. The initial proton beam momentum, intensity and polarization were
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