Oasis: A New System to Acquire and Display the Analog Signals for LHC

To cope with the user requirements for the Large Hadron Collider (LHC) era, a new system has to be developed for the acquisition and display of analog signals in the accelerator domain. OASIS, the Open Analog Signals Information System, extends the capabilities of the existing 'new Analogue observation system' (nAos) in many fronts : new acquisition hardware is supported to provide higher analog bandwidth to the users, a new distributed triggering scheme has been designed for greater flexibility and the software has been completely redesigned with openness in mind to allow easy upgrading and maintainability. This paper describes the architecture chosen to satisfy the new user requirements. The solution involves three tiers and makes use of the J2EE platform to communicate between the GUI and the middle tier. The front-end tier runs on Linux PCs in CompactPCI format, to support fast digitizer modules. A first prototype system, used for the extraction tests from the Super Proton Synchrotron (SPS) to the LHC, is also presented.