Speaker
Kazu Carvalho Akiba
(Univ. Federal do Rio de Janeiro (BR))
Description
The LHCb detector is a single-arm forward spectrometer covering the
pseudorapidity range $2<\eta <5$, designed for the study of particles
containing $b$ or $c$ quarks. The detector includes a high-precision tracking
system consisting of a silicon-strip vertex detector (VELO) surrounding the
$pp$ interaction region, a large-area silicon-strip detector located upstream
of a dipole magnet and three stations of silicon-strip detectors and straw
drift tubes placed downstream of the magnet. Calorimeters, RICH and Muon
detectors for particle identification complement the detector.
The VELO comprises 42 modules made of two n$^+$-on-n 300 $\mu$m thick
half-disc silicon sensors with R-measuring and Phi-measuring micro-strips,
featuring a double metal layer for signal routing. One upstream module is
manufactured with n$^+$-on-p technology, allowing a direct comparison of the
two technologies. The VELO is installed as two movable halves containing 21
modules each to ensure its safety during beam injection.
The extreme proximity (~8 mm) of the VELO sensors to the LHC beam renders the
VELO an ideal laboratory to study the effects of radiation damage on silicon
detectors. Therefore, and to ensure efficient operation until the end of LHC
Run 2, the radiation damage is studied closely with several methods
complementing one another: IV scans, IT scans and CCE scans. The latest
results as well as operational challenges for the VELO in LHC Run 2 will be
presented.
Author
Kazu Carvalho Akiba
(Univ. Federal do Rio de Janeiro (BR))
