The BaBar drift chamber

A search for the decay of a B meson into a kaon and a tau lepton pair at the BaBar experiment

“…To meet the physics requirements of the experiment, the BABAR DCH provided a spatial resolution better than 140 µm, averaged over the cells. For separation between K and π mesons, with energies up to 700 MeV/c 2 , the required resolution for dE/dx measurements, combined over all hits, was ∼ 7% [66].…”

Measurement of Mixing and CP Violation in the Two-Body D0 decays to KK, pipi and Kpi with the BaBar Experiment

“…2.10. It consists of a 280 cm long cylinder located within the volume inside the DIRC and outside the PEP-II support tube [39]. The active volume provides charged particle tracking over the polar angle range 17.2 • < θ LAB < 152.6 • .…”

A Study of Double-Charm and Charm-Strange Baryons inElectron-Positron Annihilations

“…The DCH subsystem [19] surrounds the SVT to provide additional tracking of charged particles (which primarily determines transverse momentum) and to measure dE/dx. It is also essential in determining the decay vertexes of longer-lived neutral particles, such as the Λ 0 and the K s , that can decay into charged particles many centimeters away from the e + e − interaction point.…”

“…The PDF component used to describe background for Λ + c K − candidates is proportional to the function 18) where T is the kinematic threshold of 2780.14 MeV/c 2 , and κ and ρ are free parameters. The fit range, 2.91 GeV/c 2 to 3.15 GeV/c 2 , is specifically chosen to be narrow enough to allow for these simple functional forms for the background PDF components while being wide enough to encompass about 19) where M and Γ are the mass and width of the signal as measured from the fit to three-body decay data, and µ and γ are the signal mass and width parameters from the two-body fit.…”