Central Time-of-Flight

The Jefferson Lab CLAS12 Central Time-of-Flight apparatus is a barrel scintillation detector for triggering and time-of-flight measurements in the central region of the detector. JLab's goal is for the CTOF to achieve a resolution time of 50-60 ps (picoseconds) (1 ps = 1 x 10^-12 s).

Setup
The nominal barrel geometry includes 48 scintillating counters, each 0.9 m (90 cm) long and approximately 3.5 x 3 cm in cross section, and straight 1 m-long (upstream) and bent 1.6 m-long (downstream) focusing light guides made of cast acrylic. A Hamamatsu R2083 photomultiplier will be used to view the ends of each CTOF counter.

The CTOF scintillators will be placed inside the superconducting solenoid at a 25 cm radius from the beam axis.

Links/Sources
CLAS12 Central Time of Flight System: http://www.jlab.org/Hall-B/clas12-web/subsystems/ctof-intro.html