Picosecond timing
A picosecond is a millionth of a millionth of a second. A micrometer is a thousandth of a millimeter. Our goal is to measure the positions of charged particles with a 30-picosecond timing resolution and a 30-micrometer position resolution. Today, this is not possible. We are attempting to reach this precision using Low-Gain-Avalanche-Diode detectors.
The challenges are :
- Current sensors have a dead area around them, leading to large inefficiencies when they are made into small pixels.
- It is a challenge to fit the timing readout electronics on small pixels.
- Radiation levels at the LHC destroy the gain layer that provides the fast signal.
- These detectors consume more power and generate more heat than traditional detectors due to their fast electronics.
Our group has made the first measurements of timing resolution of small-pixel LGADs. Together with PSI, we are developing small pixel-sized readout electronics that can utilize these small sensors.