Dose Rate Monitor System Based On EPICS For The HLS-?

The Hefei Light Source,renamed as HLS-? after a major renovation,is a second generation synchrotron radiation light source,and composed of an 800 MeV linear accelerator,a transport line and an 800 MeV storage ring.In order to eliminate the radiation pollution to people and surrounding area,the radiatin shielding should be built according to the principle which stated as "As Low As Reasonably Achievable(ALARA)".To better serve for user experiments,the HLS is undergoing an upgrade for the top-off operation mode.The old radiation dose rate monitor system of the HLS was designed and built for the decay operation mode.People can not stay in the experiment hall while injecting beam into the storage ring.In order to meet the requirement of the top-off operation,the radiation dose rate monitor system is overhauled in the upgrade.The new radiation dose rate monitor system is developed based upon the Experimental Physics and Industrial Control System(EPICS),and integrated into the HLS-? control system.The system is comprised of detectors,communication modules,data sampling and monitoring software,and data analysis system.This system can be used not only to monitor the radiation dose rate in the light source and surrounding areas,but also to perform integral dose calculation,history data query and interlock protections.The opening of the beam scraper is reduced to some extent to make electrons are mostly lost at the location of the scraper.Lead bricks are installed around the scrapper to provide localshielding.Particle trackings using Accelerator Toolbox(AT)with different scraper openings are performed to check the effectiveness of the shielding.More than seven months of operation indicates that this system is reliable and well fulfills the demand of the top-off operation of the HLS-?.