Measurement of K∗(892)0K^*(892)^0 and K0K^0 mesons in Al+Al collisions at 1.9AA GeV

New measurement of sub-threshold $K^*(892)^0$ and $K^0$ production is presented. The experimental data complete the measurement of strange particles produced in Al+Al collisions at 1.9$A$ GeV measured with the FOPI detector at SIS/GSI. The $K^*(892)^0$ / $K^0$ yield ratio is found to be $0.0315\pm 0.006 (\mathrm{stat.})\pm 0.012 (\mathrm{syst.})$ and is in good agreement with the UrQMD model prediction. These measurements provide information on in-medium cross section of $K^+$ - $\pi^-$ fusion which is the dominant process on sub-threshold $K^*(892)^0$ production.Comment: 5 pages, 4 figures, accepted for publication in Phys. Rev.

Diffuse Neutron Scattering in the Mn0.4Cu0.6Mn_{0.4}Cu_{0.6} Alloy

The diffuse neutron scattering in the $Mn_{0.4}Cu_{0.6}$ alloy was measured in the temperature range 15-390K at the 3-axis neutron spectrometer at MARIA reactor in Świerk. The broad maxima of the neutron intensity were observed in the surrounding of the (0.5, 1, 0) reciprocal lattice point and other symmetry related points. The effect is similar to that observed in Mn-Cu alloys with lower Mn content at room temperature. Our results are in agreement with the earlier finding that the maxima of the short-range order incommensurate spin density wave scattering are placed at the (0.5±δ, 1, 0) reciprocal lattice point with a linear dependence of δ on the Mn concentration. In addition, some commensurate antiferromagnetic short-range order was found

zoladek.indd

Abstract. The results of the experiments on water migration in unsaturated beds of natural zeolite (clinoptilolite) performed with a dynamic neutron radiography technique are presented. It was found that the migration of water in zeolites is much slower than in quartz sand composed of the same size grains. The effect is attributed to the enormous grain surface roughness of the zeolite. The influence of gravity was found to be significant only for beds formed by the coarsest grains. It was found that the water imbibition rate increases with time in finest grain zeolite beds. The results show the difficulties of the classical theory of adhesion driven motion of the liquid in the single capillary as a model of water imbibition by zeolite beds

Diffuse Neutron Scattering in the Mn 0.4

The diffuse neutron scattering in the $Mn_{0.4}Cu_{0.6}$ alloy was measured in the temperature range 15-390K at the 3-axis neutron spectrometer at MARIA reactor in Świerk. The broad maxima of the neutron intensity were observed in the surrounding of the (0.5, 1, 0) reciprocal lattice point and other symmetry related points. The effect is similar to that observed in Mn-Cu alloys with lower Mn content at room temperature. Our results are in agreement with the earlier finding that the maxima of the short-range order incommensurate spin density wave scattering are placed at the (0.5±δ, 1, 0) reciprocal lattice point with a linear dependence of δ on the Mn concentration. In addition, some commensurate antiferromagnetic short-range order was found

Dynamic neutron radiography studies of water migration in beds of natural zeolite

The results of the experiments on water migration in unsaturated beds of natural zeolite (clinoptilolite) performed with a dynamic neutron radiography technique are presented. It was found that the migration of water in zeolites is much slower than in quartz sand composed of the same size grains. The effect is attributed to the enormous grain surface roughness of the zeolite. The influence of gravity was found to be significant only for beds formed by the coarsest grains. It was found that the water imbibition rate increases with time in finest grain zeolite beds. The results show the difficulties of the classical theory of adhesion driven motion of the liquid in the single capillary as a model of water imbibition by zeolite beds

Anisotropy of the Neutron Scattering in the Paramagnetic Phase and on the Spin Waves in the Mn 0.71

We have confirmed the significant anisotropy of the generalised magnetic susceptibility in the paramagnetic and antiferromagnetic phase of the fcc Mn-Ni alloys. In this paper the detailed account of the experiments performed on the $Mn_{0.71}Ni_{0.29}$ alloy is given. Our main result for the paramagnetic phase is that the correlation length is larger for the direction parallel to the anisotropy axis than for the perpendicular one by a factor of 1.6. The spin-wave velocity observed at 15 K is higher for the direction parallel to the anisotropy axis than that for the perpendicular direction by a factor of 1.2. These results are similar to that for the $Mn_{0.62}Ni_{0.38}$ alloy. Our results indicate that the magnetic carriers are more localized and the magnetic interactions are less extended in alloys with higher Ni concentration

Anisotropy of the Neutron Scattering in the Paramagnetic Phase and on the Spin Waves in the Mn0.71Ni0.29Mn_{0.71}Ni_{0.29} Alloy

We have confirmed the significant anisotropy of the generalised magnetic susceptibility in the paramagnetic and antiferromagnetic phase of the fcc Mn-Ni alloys. In this paper the detailed account of the experiments performed on the $Mn_{0.71}Ni_{0.29}$ alloy is given. Our main result for the paramagnetic phase is that the correlation length is larger for the direction parallel to the anisotropy axis than for the perpendicular one by a factor of 1.6. The spin-wave velocity observed at 15 K is higher for the direction parallel to the anisotropy axis than that for the perpendicular direction by a factor of 1.2. These results are similar to that for the $Mn_{0.62}Ni_{0.38}$ alloy. Our results indicate that the magnetic carriers are more localized and the magnetic interactions are less extended in alloys with higher Ni concentration

The Effect of Sodium Chloride on the Process of Drying of Porous Media

The high temperature drying process of corundum cylinders partially saturated with aqueous solutions of sodium chloride was investigated with neutron imaging technique accompanied with mass and temperature measurements. The statistical analysis of neutron images was applied in order to quantify the time evolution of the process. The substantial slowing down of drying with increasing salt concentration was found. This effect was attributed to increase of viscosity of the solution with increasing salt content as well as to the formation of an outer layer of NaCl on the sample surface

The Effect of Sodium Chloride on the Process of Drying of Porous Media

The high temperature drying process of corundum cylinders partially saturated with aqueous solutions of sodium chloride was investigated with neutron imaging technique accompanied with mass and temperature measurements. The statistical analysis of neutron images was applied in order to quantify the time evolution of the process. The substantial slowing down of drying with increasing salt concentration was found. This effect was attributed to increase of viscosity of the solution with increasing salt content as well as to the formation of an outer layer of NaCl on the sample surface

Neutron Radiography Studies of Water Self-Diffusion in Porous Medium

The results of neutron radiography studies on macroscopic self-diffusion of water confined within rigid porous material reveal the substantial reduction in diffusion constant in comparison to the diffusion in large volume. The studies performed in the 30-50°C temperature range on fired clay brick of 30% porosity show decrease in diffusion constant to approximately 17% of its value for free space and the Archie exponent is 1.4. The Arrhenius law was confirmed and the activation energy was found of the same value as in the water bulk