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The paper presents results on measuring the polarization in the reaction π − p→ π 0 n at 40 GeV/ c in the 4-momentum transfer range 0 t |⩽2 (GeV/ c ) 2 . The results based on the statistics of about 2.2 million recorded events made it possible to observe a noticeable value and complex structure in the polarization behaviour up to | t |⩽2 (GeV/ c ) 2 .

Differential cross sections for the elastic scattering of negative pions on protons, as well as total cross sections have been measured for the incident momentum range from 33 up to 60 GeV/c. The values for four-momentum transfer were within the limits of −(10−3−8·10−2) (GeV/c)2. The energy dependence of the ratio ϱ(0) of the real part of the forward elastic scattering amplitude to the imaginary part has been determined from the experimental data. The magnitude ϱ(0) smoothly increases from (−10.9 ± 1.2)% at momenta 33.52 GeV/c up to (−1.8 ± 1.8)% at 59.4 GeV/c. The results obtained are compared with the predictions of theoretical models.

The polarization parameter in the reactions π−p→ηn and π−p→η′n at 40 GeV/c with −t ranging from 0 to 2.6 (GeV/c)2 and 1.0 (GeV/c)2, respectively, was measured in experiments using a propanediol polarized target. Only gamma particles from the neutral meson decay were detected. The polarization parameter of the first reaction turns out to be negative in a widet interval (0.05

The π − p differential elastic scattering cross sections have been measured for eight momenta in the 33–55 GeV/ c range. The energy dependence of the slope and of the total elastic scattering cross sections has been determined experimentally. The results are compared with the known data. The experimental data are compared both with the Regge pole model and with the quasi-potential one.

The polarization parameter P has been measured for elastic π + p, K + p and pp scattering at 45 GeV/c. Four-momentum transfer ranges from −0.08 to −1.1 (GeV/) 2 for pp, and from −0.08 to −0.9 (GeV/) 2 for π + p and K + p. The energy dependence of the polarization P ( t ) in π + p and in K + p above 6 GeV/c incident momentum is compatible with interference between pomeron and Regge poles. On the other hand, the polarization in p p elastic scattering decreases faster than ordinary Regge model predictions. This result can be explained by interference between non flip and flip amplitudes of the pomeron, leading to negative values for the polarization.

The spin rotation parameterR in pp and π+ p elastic scattering at 45 GeV/c has been measured at the Serpukhov accelerator, for ¦t¦ ranging from 0·2 to 0·5 (GeV/c)2. The results are presented, together with previousR measurements at lower energies, and are compared with the predictions of Regge pole models. The equality of the values forR in proton-proton and pion-proton scattering, within the experimental errors, is a test of factorization of the residues.

The polarization parameterP has been measured for elastic scattering on polarized protons, of π−, K− and ¯p at 40 GeV/c and of π+, K+ and p at 45 GeV/c. Four-momentum transfer ranges from −0·08 to −1·8 (GeV/c)2 for π−p, and from −0·08 to about −1sd0(GeV/c)2 for p, π+, K± and ¯p. The angular distribution of the polarization in π−p exhibits the well known non sense double zero att=−0·6 (GeV/c)2. The K−p and ¯pp results are compatible with exchange degeneracy for ¦t¦r

We report final results on the polarization parameter P in elastic scattering of π − , K − and antiprotons at 40 GeV/ c incident momentum. The energy dependence of P (t) in π − p above 10 GeV/ c is well fitted by P (t) α s αR(t)-α P (t) where α R (t) are the effective Regge and Pomeron trajectories respectively. The data in K − p are compatible with exchange degeneracy. The results inp¯p show an important structure for |t|> 0.3 (GeV/c) 2 demonstrating the existence of a large helicity flip amplitude.

The differential cross sections for elastic π − p, K − p , p p and π + p, pp scattering at 39 and 44.5 GeV/c, respectively, have been measured in the interval of momentum transfer squared 0.15 ≤ ovbt| ≤ 2 (GeV/c)2.

The helicity amplitudes for isospin-0 exchange are determined at 40 GeV/ c . For isospin-1 exchange only partial information is obtained. The model-independent analysis is extended to the four-momentum transfer interval from t = 0 to t = −0.6 (GeV/ c ) 2 . One of the two solutions presented has a behaviour similar to the previous results at lower energy.

Inclusive cross sections for π− + p → π− + X+ reaction have been measured for the interval x = p/pmax = 0.90–0.99 at the momenta 42 and 51 GeV/c and the values of the momentum transfer squared p⊥2 = 0.04 + 0.26 (GeV/c)2. With the increase of x one can observe some growth of invariant differential cross section at p2 fixed in the indicated interval. In the Regge pole model such a behaviour may be explained by a predominating contribution of the vacuum pole. Under this assumption we have found that energy dependence of the total cross section for Pomeron interaction with protons at several values of p⊥2.

The main parts of an apparatus for simultaneous measurements of the polarization and spin-rotation parameters in high-energy elastic scattering on polarized protons are described, including the beam design, the polarized target, detectors, fast electronics, and the data acquisition. Measurements have been performed in 1972 to 1974 at the Serpukhov accelerator with π − , K − and p of 40 GeV/ c , and with p, π + and K + of 45 Ge V / c incident momentum. In addition to the results for P and R , the experiment also yields information on the unpolarized differential cross section.

The spin rotation sf R in pp and π + p elastic scattering at 45 GeV/c has been measured at the Seppukhov accelarator, for z . sfnc ; t |; ranging from 0.2 to 0.5 (GeV/) 2 . The results are presented, together with previous R measurements at lower energies. The equality of the values for R in proton-proton and pion-proton scattering, within the experimental errors, is a test of factorization of the residues in the pomeron exchange.

First results on measuring polarization in π - p →π°n reaction at 40 GeV/c are presented for the 4-momentum transfer range from 0.05 up to 0.4 (GeV/c)2. The experiment was carried out at the IHEP 70 GeV accelerator on a polarized proton target. Polarization in this reaction was earlier studied at incident momentum below 11.2 GeV/c/1–4/. Comparison of the present data with the previous ones allows us to see the polarization effect decreases with energy growth.