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Currently the tagged neutron method (TNM) is actively used to determine the elemental composition of various substances: sinter, coal, iron and phosphate ores. The tagged neutron method consists in irradiation of the substance under study by fast neutrons with an energy of 14 MeV and registration of the induced characteristic gamma radiation. Neutron tagging is carried out by an alpha detector built in a neutron generator. The results of operation of TNM analyser for determination of elemental composition of iron ore are discussed.

We present a measurement of the deuteron spin-dependent structure function g1d based on the data collected by the COMPASS experiment at CERN during the years 2002-2004. The data provide an accurate evaluation for Gamma_1^d, the first moment of g1d(x), and for the matrix element of the singlet axial current, a0. The results of QCD fits in the next to leading order (NLO) on all g1 deep inelastic scattering data are also presented. They provide two solutions with the gluon spin distribution function Delta G positive or negative, which describe the data equally well. In both cases, at Q^2 = 3 (GeV/c)^2 the first moment of Delta G is found to be of the order of 0.2 - 0.3 in absolute value.

The production of Lambda and Lambda-bar hyperons by polarized muons of 160 GeV/c on a polarized 6LiD target has been studied using the COMPASS spectrometer. First preliminary results on the longitudinal polarization of Lambda and Lambda-bar hyperons produced in the deep-inelastic scattering will be presented for 2002 data set.

A study of the reaction pi+ + d --> p + p has been performed in the energy range of 18 - 44 MeV. Total cross sections and differential cross sections at six angles have been measured at 15 energies with an energy increment of 1 - 2 MeV. This is the most systematic data set in this energy range. No structure in the energy dependence of the cross section has been observed within the accuracy of this experiment.

Azimuthal asymmetries in semi-inclusive production of positive ( h + ) and negative hadrons ( h − ) have been measured by scattering 160 GeV muons off longitudinally polarised deuterons at CERN. The asymmetries were decomposed in several terms according to their expected modulation in the azimuthal angle φ of the outgoing hadron. Each term receives contributions from one or several spin and transverse-momentum-dependent parton distribution and fragmentation functions. The amplitudes of all φ -modulation terms of the hadron asymmetries integrated over the kinematic variables are found to be consistent with zero within statistical errors, while the constant terms are nonzero and equal for h + and h − within the statistical errors. The dependencies of the φ -modulated terms versus the Bjorken momentum fraction x , the hadron fractional momentum z , and the hadron transverse momentum were studied. The x dependence of the constant terms for both positive and negative hadrons is in agreement with the longitudinal double-spin hadron asymmetries, measured in semi-inclusive deep-inelastic scattering. The x dependence of the sin  φ -modulation term is less pronounced than that in the corresponding HERMES data. All other dependencies of the φ -modulation amplitudes are consistent with zero within the statistical errors.

The production of D ∗ and D mesons in inelastic scattering of 160 GeV/c muons off a 6 LiD target has been investigated with the COMPASS spectrometer at CERN for 0.003 (GeV/c) 2 < Q 2 <10 (GeV/c) 2 and 3×10 −5 < x Bj <0.1. The study is based on 8100 events where a D 0 or is detected subsequently to a D ∗+ or D ∗− decay, and on 34000 events, where only a D 0 or is detected. Kinematic distributions of D ∗ , D and are given as a function of their energy E , transverse momentum p T , energy fraction z , and of the virtual photon variables ν , Q 2 and x Bj . Semi-inclusive differential D ∗ production cross-sections are compared with theoretical predictions for D ∗ production via photon–gluon fusion into open charm. The total observed production cross-section for D ∗± mesons with laboratory energies between 22 and 86 GeV is (1.9±0.4) nb. Significant cross-section asymmetries are observed between D ∗+ and D ∗− production for ν <40 GeV and z >0.6.

Large samples of Λ , Σ (1385) and Ξ (1321) hyperons produced in the deep-inelastic muon scattering off a 6 LiD target were collected with the COMPASS experimental setup at CERN. The relative yields of Σ (1385) + , Σ (1385) − , , , Ξ (1321) − , and hyperons decaying into were measured. The ratios of heavy-hyperon to Λ and heavy-antihyperon to were found to be in the range 3.8 % to 5.6 % with a relative uncertainty of about 10 %. They were used to tune the parameters relevant for strange particle production of the LEPTO Monte Carlo generator.

The longitudinal double spin asymmetry A1ρ for exclusive leptoproduction of ρ0 mesons, μ+N→μ+N+ρ, is studied using the COMPASS 2002 and 2003 data. The measured reaction is incoherent exclusive ρ0 production on polarised deuterons. The Q2 and x dependence of A1ρ is presented in a wide kinematical range, 3×10-3

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