Speaker
Dr
Thomas Bergauer
(HEPHY Vienna)
Description
The Belle experiment at the KEK-B electron/positron collider in Tsukuba (Japan) has been successfully operating for more than ten years. A major update of the machine to SuperKEKB is now foreseen until 2014, aiming a 40-fold peak luminosity compared to the previous system. This also requires a redesign of the Belle detector (leading to Belle II) and especially its Silicon Vertex Detector (SVD).
The future Belle II SVD will consist of four layers of double-sided silicon strip sensors (DSSD) entirely made from 6" wafers. Moreover, an inner double-layer pixel detector based on DEPFET technology will complement the SVD as innermost detector and the SVD itself will now contain a slanted forward part. The DSSDs are arranged in the so-called "Origami" chip-on-sensor concept to minimize material budget. This is complemented by a very lightweight mechanical support structure made from carbon fiber reinforced Airex foam and a CO$_2$ cooling system with extremely thin pipes.
Since the detector has to operate in an environment with high occupancy and continuous collisions, a hit-time-finding algorithm has been developed to narrow down the effective shaping time of the readout chips to a few nanoseconds.
In this talk, an overview of the Belle II SVD design will be given, covering the silicon sensors, the readout system and the lightweight support structures. A strong emphasis will be given to the status of prototype modules and its performance in recent beam tests.
Primary author
Dr
Thomas Bergauer
(HEPHY Vienna)
Co-authors
Annekathrin Frankenberger
(HEPHY Vienna)
Christian Irmler
(HEPHY Vienna)
Immanuel Gfall
(HEPHY Vienna)
Manfred Valentan
(HEPHY Vienna)
Markus Friedl
(HEPHY Vienna)
Toru Tsuboyama
(KEK)
Yoshiyuki Onuki
(Univ. of Tokyo, IPMU)
