C. Amsler, I. Johnson, H. Pruys, C. Regenfus, J. Rochet
We have built the vertex detector for the
ATHENA experiment (production and spectroscopy of anti-hydrogen) at CERN. The silicon tracker provides trigger information of the anti-hydrogen annihilation and allows to reconstruct the vertex.32 silicon detector modules are used to construct two barrel layers. Each module consists of two double sided silicon detectors connected to
VA readout chips.Photo of the inner layer of the silicon microstrips detector
We are also involved in the R&D work of the crystal calorimeter of
ATHENA, which detects 511 keV annihilation photons. The calorimeter consists of CsI(pure) crystals read out by avalanche photodiodes.The whole detector will be housed inside a vacuum vessel at 77 K.
Picture of a 22Na spectrum measured with a CsI crystal
The mechanics holding the silicon detector modules and the CsI crystal was constructed in our workshop.
Picture of the mechanics design
