The metal surface of accelerating structures emits electron currents when operating at rf electric fields higher than 100 MV/m. These “dark currents” may have deleterious effects such as creating backgrounds for beam diagnostics, generating X-rays, loading rf power. They will also interact with the primary electron (or positron) bunch being accelerated in the structure, to kick the beam centroi...

In a Storage Ring Free Electron Laser (SRFEL) there is a strong interdependence between the laser beam and the electron beam from which the laser is generated. The Super ACO storage ring has a second Radio Frequency (RF) cavity at the 5th harmonic of the main RF cavity. It is used to shorten the bunch length, thereby enhancing the laser gain. Employing this RF harmonic cavity instabilities are ...

objective: the aim of this study is to evaluate the effect of tissue composition on dose distribution in electron beam radiotherapy. methods : a siemens primus linear accelerator and a phantom were simulated using mcnpx monte carlo code. in a homogeneous cylindrical phantom, six types of soft tissue and three types of tissue-equivalent materials were investigated. the tissues included muscle (s...

Background: The herb feverfew (Tanacetum parthenium L., Asteraceae) has an ancient reputation as an effective anti-inflammatory, analgesic, antipyretic, and anti-asthmatic agent. Parthenolide a gemacranolide-type sesquiterpene lactone is the major constituent of European feverfew. Materials and Methods: The present study was intended to evaluate the in vivo antioxidant potential and radioprotec...