D. R. Johnson
University of Colorado Boulder
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Publication
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Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment | 1996
Y. Arai; J.G. Arnold; J.W. Barkell; B. Bevensee; B. Broomer; J. Chapman; M. Chiba; T. Collins; M. Corden; D. Craig; D.M. Davis; N. Dressnandt; A. Dunn; William L. Dunn; T. Ekenberg; M.S. Emery; T. Emura; E. Erdos; W. T. Ford; T. A. Gabriel; A. T. Goshaw; S. V. Greene; M. van Haaren; D.T. Hackworth; R. Hamatsu; G. Hanson; T. Hirose; M. Ikeno; Q.P. Jia; D. R. Johnson
Abstract We have developed the baseline design for a straw drift tube tracking system for the Solenoidal Detector Collaboration (SDC) detector. The system was designed to operate in the high-rate environment of a high luminosity hadron collider. We present an overview of the tracking system and the requirements it was expected to fulfill. We describe the construction and properties of the straw drift tubes. We discuss the design of the carbon-fiber foam-laminate shell, which supported the wire tension and held the straws in alignment. We also present descriptions of the designs of the front-end and digitization electronics as well as the electronics associated with the level 1 track trigger.
Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment | 1998
A. Boucham; I. De Bonis; A. Jeremie; Y. Karyotakis; R. Lafaye; C. Goodenough; C. Hearty; J. Heise; M. Kelsey; J. A. McKenna; D.E. Dorfan; J. Fernandez; H. F.-W. Sadrozinski; B. A. Schumm; N. Spencer; J. L. Harton; R. Malchow; M.B. Smy; D. Warner; B. Broomer; E. Erdos; W. T. Ford; A. Gritsan; D. R. Johnson; H. Krieg; J. Roy; Harold S. Park; P. Rankin; J. G. Smith; A. Gaddi
The BaBar Drift Chamber is now under construction. We review its design, the progress in the construction of the components, the plan for assembly and stringing and we present test results obtained with a prototype exposed at SLAC to cosmic rays. We also report on projected dE/dx performance from beam tests done with a chamber with a different cell design.
Prepared for | 1998
A. Boucham; D. Pitman; D. G. Fong; R. K. Yamamoto; G. Sciolla; D. Britton; E. Erdos; M. Momayezi; D. Warner; R. Malchow; A. Gaddi; B. Broomer; A. V. Gritsan; P. Taras; H. Park; M. Morandin; S. Santi; E. Lamanna; H. Krieg; I. De Bonis; Abolhassan Jawahery; C. Voci; R. Bard; W. Miller; S. Morganti; F. Raffaelli; F. Ferroni; A. J. S. Smith; M.B. Smy; M. Houde
The BaBar Drift Chamber is now under construction. We review its design, the progress in the construction of the components, the plan for assembly and stringing and we present test results obtained with a prototype exposed at SLAC to cosmic rays. We also report on projected dE/dx performance from beam tests done with a chamber with a different cell design.
Physical Review D | 1992
M. Daoudi; W. T. Ford; D. R. Johnson; K. Lingel; M. Lohner; P. Rankin; J. G. Smith; J. P. Alexander; C. Bebek; K. Berkelman; D. Besson; T. E. Browder; D. G. Cassel; E. Cheu; D. M. Coffman; P. S. Drell; R. Ehrlich; R. S. Galik; M. Garcia-Sciveres; B. Geiser; B. Gittelman; S. W. Gray; D. L. Hartill; B. K. Heltsley; K. Honscheid; J. Kandaswamy; N. Katayama; P. C. Kim; D. L. Kreinick; J. D. Lewis
We have made measurements of several {ital D}{sub {ital s}} branching ratios, relative to the {phi}{pi}{sup +} mode. We have observed two previously unseen two-body hadronic decays of the {ital D}{sub {ital s}}{sup +}, namely {eta}{rho}{sup +} and {eta}{prime}{rho}{sup +}, and measured relative branching ratios of 2.86{plus minus}0.38{sub {minus}0.38}{sup +0.36} and 3.44{plus minus}0.62{sub {minus}0.46}{sup +0.44}, respectively. We have determined the relative branching ratio for the decay into {phi}{rho}{sup +} to be 1.86{plus minus}0.26{sub {minus}0.40}{sup +0.29}. In addition, we have measured relative branching ratios for the {eta}{pi}{sup +} and {eta}{prime}{pi}{sup +} states, for which there had previously been conflicting measurements; our results are 0.54{plus minus}0.09{plus minus}0.06 and 1.20{plus minus}0.15{plus minus}0.11, respectively. Combining these new measurements with previous results and using (3.7{plus minus}1.2)% for the value of {ital scrB}({ital D}{sub {ital s}}{r arrow}{phi}{pi}{sup +}), we can account for {approx}(79{plus minus}26)% of all {ital D}{sub {ital s}}{sup +} decays. In addition we have also measured relative branching ratios or set upper limits on {ital D}{sup +} decays to all of the above-mentioned final states.
Physical Review D | 1992
R. Ammar; P. Baringer; D. Coppage; R. Davis; M. Kelly; N. Kwak; H. Lam; S. Ro; Y. Kubota; M. Lattery; J. K. Nelson; D. Perticone; R. Poling; S. Schrenk; R. Wang; M. S. Alam; I. J. Kim; B. Nemati; V. Romero; C. R. Sun; P. N. Wang; M. M. Zoeller; G. Crawford; R. Fulton; K. K. Gan; H. Kagan; R. Kass; J. Lee; R. Malchow; F. Morrow
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