Fig. 1
From: Block segmentation in feature space for realtime object detection in high granularity images
Schematic of a generic pixel detector at a colliding-beam experiment. Five cylindrical layers of silicon pixel sensors (shown in red), each 1 m long and radially spaced 5 cm apart, are concentric with the longitudinal (beam) axis. Not shown is the large concentric solenoid that produces an axial magnetic field which bends the charged particles in the azimuthal direction. (Left) Three particles, of transverse momenta of 10 GeV/c (solid curve), 1 GeV/c (dashed curve) and 0.1 GeV/c (dotted curve) respectively, produced in a pp collision are shown traversing the sensor layers in the transverse (azimuthal) view. The azimuth is divided into 128 wedges as described in the text; the overlaps between adjacent wedges (shown in blue) are due to their arc-shaped boundaries designed for containment of \(p_T> 10\) GeV/c particles. (Right) In the longitudinal (z) view, four particles, each of transverse momenta of 20 GeV/c, are shown. The horizontal dotted line indicates the beam axis. Example collision points are at \(z_0 = \pm 15\) cm, the ends of the luminous region, and the particles pass through the edge of the acceptance of the outermost sensor layer.
