Experience with beam induced backgrounds in the DA/spl phi/NE detectors

DA/spl Phi/NE is a high luminosity double ring electron-positron collider working at the energy of the /spl Phi/ resonance (1.02 GeV c.m.). Two experiments, KLOE and DEAR are presently taking data at DA/spl Phi/NE. At the beginning of data taking, both experiments suffered from large beam induced background, mainly due to Touschek scattering. Measurements of the background rates in different configurations as well as simulations and tracking studies have been performed in order to find the proper actions that allow reducing these rates. In particular measurements and simulations on the collimation efficiency of the scraper system and the consequent modifications adopted to improve the system are presented.