Particle timing detector with unprecedented resolution by JLO

The timing detector AFP/ToF that has been from a large part designed, manufactured and operated by a team of physicists form the JLO, has been found to measure arrival times of high energy particles with resolution of about 25 ps. This corresponds to a spatial resolution of just 8 mm for the place of interaction of protons moving at almost the speed of light, measured by ToF detectors located at a distance of 200 m around the heart of the ATLAS experiment. The ToF detector has been operated in extreme conditions close to the particle beams at the LHC. The measured time resolution represents the best value obtained in applications of a similar sort so far. The precise measurement of the time of flight helps the ATLAS physicists to achieve better separation of the so called diffractive signal from background. The detailed study by K. Černý, one of the first physics results of the AFT/ToF detector, was published as a public performance note of the ATLAS experiment, with key contributions by scientists of the JLO laboratory