Title screen

References: p. 1035 (9 tit.)

The first experiment on Cherenkov light from 255-MeV electrons passing through a 50-?m-thick diamondcrystal in a special geometry allowing extraction of 500-nm Cherenkov light at a right angle with respectto the electron beam direction has been performed at the injector linac of SAGA Light Source acceleratorfacility. The dependence of 500-nm Cherenkov light intensity (separated by a band-pass filter) on thecrystal rotation angle was measured by a CCD detector. The experimentally obtained rocking curvewith an intense maximum is theoretically explained as the projector effect of Cherenkov light deflectedby the exit surface of the crystal. The width of the rocking curve is explained by the convolution ofthe standard Tamm–Frank angular distribution of Cherenkov radiation with chromatic aberration, themultiple scattering of electrons in a crystal, and initial electron beam angular divergence. In addition, itis found that the Cherenkov light intensity did not change under the (220) planar channeling condition,which is consistent with a recent theory.