Abstract
The Ring Imaging Cherenkov detectors of the LHCb experiment at the Large HadronCollider at CERN are equipped with Hybrid Photo-Detectors. These vacuumphoto-detectors are affected by the stray magnetic field of the LHCb magnet,which degrades their imagingproperties. This effect increasesthe error on the Cherenkov angle measurement and would reduce the particle identification capabilities of LHCb.A system has been developed for the RICH2 RingImaging Cherenkov detector to perform a detailed characterisation of the magneticdistortion effects. It is described, along with the methods implemented to correct for these effects,restoring the optimal resolution.
Highlights
The PID capabilities of the LHCb apparatus rely on its two Ring Imaging Cherenkov detectors, RICH1 and RICH2 [1, 4]
The strong polar angle and momentum correlation can be exploited by a system of two RICHes: RICH1 and RICH2
The effect of the stray magnetic field on the photoelectrons trajectories depends on the intensity and direction of the magnetic field inside the Hybrid Photo-Detectors (HPD) [9]
Summary
The PID capabilities of the LHCb apparatus rely on its two Ring Imaging Cherenkov detectors, RICH1 and RICH2 [1, 4]. The RICH1 detector is located close to the interaction point, upstream of the LHCb magnet, with 25−300 mrad polar angular acceptance. It employs C4F10 gas and silica aerogel as Cherenkov radiators providing particle identification of low momentum tracks, over the range 1 − 40 GeV/c. The RICH2 detector is located approximately half-way between the LHCb magnet and the large ferromagnetic mass of the muon detector system at a distance along the beam axis of about 6 m from the magnet centre and of about 10 m from the collision point It is intended for high momentum, up to 100 GeV/c, and small polar angle tracks, and uses a gaseous CF4 radiator. If no correction is applied, the error on the Cherenkov angle measurement increases, degrading the PID capability of LHCb
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
