André Massafferri Rodrigues
(Brazilian Center for Physics Research)
The LHCb Collaboration is currently in the final step of an upgrade that will allow the experiment to operate at much higher luminosities and with a triggerless readout. The main tracking stations which originally were subdivided in an Inner Tracker made from silicon strip sensors and an Outer Tracker built from straw-tubes is being replaced by single detector, the Scintillating Fibre Tracker (SciFi).
The SciFi covers a total detector area of 340 m2 by using more than 10,000 km of scintillating fibre with 250 μm diameter, enabling a spatial resolution of better than 100 μm for charged particles. It is built from individual modules (0.5 m × 4.8 m) comprised of 8 scintillating fibre mats with a length of 2.4 m as the active detector material. The 13 cm wide fibre mats consist of 6 layers of densely packed blue emitting scintillating fibres. The scintillation light is detected with arrays of multi-channel silicon photomultipliers (SiPMs) cooled to -40C to minimize the expected high dark noise from neutron radiation. The readout of 524k channels occurs through custom-designed front-end electronics.
Since it is the first time that this technology is been used as a large tracker and with a small granularity many challenges has to be overcome. The talk will give an overview of the SciFi detector design, production, performance and the status of the detector assembly.
In this talk I will describe the design of the new tracker of the LHCb experiment, composed by thin scintillating fibres read-out by Silicon Photo-multiplier, its front-end electronics as well as discuss all challenges involved in the production of all components and provide the progress of the ongoing phase of commissioning.