The CLAS12 Micromegas Vertex Tracker

A. Acker (1) , D. Attié (1) , S. Aune (1) , J. Ball (1) , P. Baron (1) , Q. Bertrand (1) , D. Besin (1) , T. Bey (1) , F. Bossù (1) , R. Boudouin (1) , M. Boyer (1) , G. Christiaens (1) , P. Contrepois (1) , M. Defurne (1) , E. Delagnes (1) , M. Garçon (1) , F. Georges (1) , J. Giraud (1) , R. Granelli (1) , N. Grouas (1) , C. Lahonde-Hamdoun (1) , T. Lerch (1) , I. Mandjavidze (1) , O. Meunier (1) , Y. Moudden (1) , S. Procureur (1) , M. Riallot (1) , F. Sabatié (1) , M. Vandenbroucke (1) , E. Virique (1)

1 IRFU - Institut de Recherches sur les lois Fondamentales de l'Univers

The Micromegas Vertex Tracker was designed to improve upon the tracking capabilities of the baseline design of the CLAS12 spectrometer in Hall B at Jefferson Laboratory. A Barrel Micromegas Tracker made with six concentric cylinders, each made of three 120 ∘ -sector tiles, surrounds the Silicon Vertex Tracker, and a Forward Micromegas Tracker composed of 6 disks is placed 30 cm downstream of the liquid-hydrogen target. Both trackers sit in a 5 T solenoid magnetic field. All Micromegas elements are based on resistive technology to withstand luminosities up to 1035  cm −2  s −1 , as well as on bulk technology to enforce gain uniformity and mechanical robustness. Due to the high magnetic field, dedicated electronics have been designed and displaced ∼ 2 m away from the detectors. The electronics readout is based on the DREAM ASICs that allow sustained operation up to 20 kHz trigger rate at the maximum luminosity.

Mots clés: CLAS12; Micromegas; Curved detectors; Particle tracking; DREAM ASIC; magnetic field: high; electronics: readout; tracking detector; vertex detector; integrated circuit; spectrometer; cylinder; solenoid; silicon; trigger

Domaines: Instrumentations et Détecteurs [physics.ins-det]

A. Acker, D. Attié, S. Aune, J. Ball, P. Baron, et al.. The CLAS12 Micromegas Vertex Tracker. Nucl.Instrum.Meth.A, 2020, 957, pp.163423. ⟨10.1016/j.nima.2020.163423⟩. ⟨hal-02483901⟩