Vertex Detector Options

There are two vertex detector descriptions included; a CCD pixel device which can be built by calling

 VXDBLD_CCD

or an `active pixel' design which can be build by calling

 VXDBLD_PIXEL

. The vertex detector option can be selected via the FFREAD cards as discussed above. As usual, either routine should be called within UGEOM. The geometry of the `active pixel' design is described in the CDR in some detail. The geometry of the CCD design can be found in the Lund workshop summary transparencies [5]. In version Brahms_305 the geometry of the detector has been slightly changed to correspond to the detector presented by Chris Damerell at Hamburg in November 1998, and updated in spring of 2001. Essentially the ladders have been extended in z to cover a larger solid angle. Some first estimates of materials for support structures etc are included. At the end of the active detector layers, additional pieces od silicon have been included to simulate the readout electronics. A first estimate of material for cables etc in the foward region is included This geometry should be treated as preliminary and with caution.

The VXD hits are obtained by simple spatial smearing of the energy deposits performed in the routine GUSTEP. They are contained in the array VXDHITS in the routine GUTREV.
IMPORTANT NOTE: Please treat this code with caution - it needs to be checked by the relevant detector experts.

The output hits from the VXD are contained in the array VXDHITS in the routine GUTREV.