Measurement of Beam Characteristics of Pls Linac*

The PLS (Pohang Light Source) linac has been operated routinely as the injection linac for PLS, a thirdgeneration synchrotron light source. The transverse electron beam emittance was measured at the preinjector end of the PLS linac, where the beam energy is about 100 MeV. The emittance was measured using a quadrupole magnet and a fluorescent target. We used a progressive scan CCD camera with an asynchronous random trigger shutter to obtain precise beam sizes. The beam image analysis was made with a PC equipped with a frame grabber. Bunch length was also measured at the pre-injector end using a streak camera to observe transition radiation emitted from a radiator inserted into the beam path. The measurement system and the results are described in detail.