3 research outputs found
The new ALEPH Silicon Vertex Detector
The ALEPH collaboration, in view of the importance of effective vertex detection for the Higgs boson search at LEP 2, decided to upgrade the previous vertex detector. Main changes were an increased length (±20 cm), a higher granularity for rφ view (50 µm), a new preamplifier (MX7 rad hard chip), a polymide (upilex) fan-out on z side to carry the signals from the strips to the front-end electronics outside the fiducial region reducing consequently the passive material in the central region by a factor of two. The detector, the running experience and its performance will be described
The new ALEPH Silicon Vertex Detector
The ALEPH collaboration, in view of the importance of effective vertex detection for the Higgs boson search at LEP 2, decided to upgrade the previous vertex detector. Main changes were an increased length (±20 cm), a higher granularity for rφ view (50 µm), a new preamplifier (MX7 rad hard chip), a polymide (upilex) fan-out on z side to carry the signals from the strips to the front-end electronics outside the fiducial region reducing consequently the passive material in the central region by a factor of two. The detector, the running experience and its performance will be described
Monitoring the stability of the ALEPH vertex detector
The ALEPH Silicon Vertex Detector features an optical fibre laser system to
monitor its mechanical stability. The operating principle and the general
performance of the laser system are described. The experience obtained during
1997 and 1998 operations confirms the important role that such a system can
have with respect to the detector alignment requirements. In particular, the
laser system has been used to monitor short-term temperature-related effects
and long-term movements. These results and a description of the laser-based
alignment correction applied to the 1998 data are presented.Comment: 6 pages, 9 figures, to be published in proceedings of "6th
International Conference on Advanced Technology and Particle Physics" Como
(Italy), October 199