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The characteristics of the redistribution of the intensities of passed and reflected X-rays by the Laue geometry of diffraction from the family of planes of a quartz crystal (101 ̅1) depending on the thickness of the single crystal and the magnitude of the temperature gradient were experimentally studied. In particular, the behavior of the interference absorption coefficient of X-rays depending on the thickness of the crystal and the magnitude of the thermal gradient was studied. Depending on the magnitude of the thermal gradient applied to the single crystal, measurements of both the transmitted and reflected beams, as well as their total intensities (registered at the same time) were carried out at different thicknesses.
As is known, in the presence of a temperature gradient, when the single crystal is under the condition of Bragg reflection for the Laue geometry, a significant increase in the intensity of the diffracted reflected beam is observed, and at a certain value of the action is observed a full pumping of the primary beam from the main direction to the direction of reflection. Under these conditions, a significant increase in the total intensity of the diffracted transmitted and reflected beams is observed compared to the intensity of the X-ray beam transmitted from the single crystal outside the Bragg condition, which is due to the change in the interference absorption coefficient of the radiation in the single crystal.
In this work, it is shown that the change in the total intensity (transmitted and reflected) depends both on the magnitude of the temperature gradient present in the crystal and on the thickness of the diffracting single crystal. The results of the study show that with an increase in the temperature gradient, the total intensity increases and reaches a maximum value at a certain value, and with a further increase, the total intensity begins to decrease, tending to the intensity of the beam that passed through the crystal outside the Bragg condition. As the thickness of the single crystal increases, the relative change in the total intensity increases. Let us also emphasize the following fact: for small values of the temperature gradient, a monotonic increase in both the reflected radiation intensity and the total intensity (the sum of the transmitted and reflected radiation) is observed.
