Propagation of high-intensity, high-contrast (<10−8), 50 fs laser pulses through triangular copper capillaries is experimentally studied. The relative transmission through 20-mm-long, about 50 μm wide capillaries is directly measured to be 70% for input intensities up to 1017 W/cm2. The copper reflectivity in vacuum, helium, and air is measured in the intensity range of 1010–1017 W/cm2. No reflectivity decrease in vacuum and helium is observed, which leads to the conclusion that copper capillary waveguides can efficiently guide laser pulses of intensities greater than 1019 W/cm2 on the capillary axis (that corresponds to 1017 W/cm2 on the walls). The reduction of the transmission efficiency to zero after a number of transmitted pulses is observed, which is caused by plug formation inside the capillary. The dependence of the capillary lifetime on the pulse energy is measured.

We present here the first experimental test of a singlepass non-destructive method of monitoring of longitudinal charge distribution in an intensive relativistic electron bunch. This method is based on the scanning of a thin electron beam within the energy range 20-100 kV in the electromagnetic field of an intensive relativistic bunch.The probe beam was injected across the path of primary relativistic bunch. This type of an electron beam probe is suitable for both circular or linear accelerators. The prototype results obtained at VEPP-3 storage ring are in good agreement with the calculations and give us a very high degree of confidence that this single bunch diagnostic tool can be very useful not only for accelerator tuning , but also for precise measurements.

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A 13 C-based neutron-target material is investigated using x-ray diffraction, IR absorption and Raman scattering spectroscopies, transmission electron microscopy, and electrical (conductivity, magnetoresistance, and Hall effect) measurements before and after high-power electron irradiation for various lengths of time.