Speaker
Giovanni F. Tassielli
(INFN Lecce)
Description
To optimize resolutions, both spatial and dE/dx, in a large gas drift chamber
or in a system of stacked drift tubes, the gas mixture used is such that the
ionization clusters are densely created along the charged track, thus
resulting in a signal well defined in time and dominated in amplitude by
Landau fluctuations only. Spatial resolution is limited by the primary
ionization statistics at small impact parameters and by electron diffusion at
large drift distances. Here, instead, it will be shown that, by collecting on the
sense wire all primary ionization and recording the drift times and
amplitudes of all individual ionization electrons, spatial resolution and particle
identification can be pushed to their theoretical limits of accuracy. Devices
built in such a way will prove to be ideal for colliders like SuperB, where
accuracies of the order of a few percent in dE/dx are required for particle
identification, or like the International Linear Collider, where the momentum
resolution is needed at the level of a tenth of a percent for 100 GeV/c
momenta particles. The status of the VLSI chip, designed to readout and
store the cluster counting waveforms will also be reported.
Authors
Francesco Grancagnolo
(INFN Lecce)
Giovanni F. Tassielli
(INFN Lecce)
