0000000000623777
AUTHOR
D. Ungaro
Results of proton irradiations of large area strip detectors made on high-resistivity Czochralski silicon
Abstract We have processed full-size strip detectors on Czochralski grown silicon wafers with resistivity of about 1.2 kΩ cm. Wafers grown with Czochralski method intrinsically contain high concentrations of oxygen, and thus have potential for high radiation tolerance. Detectors and test diodes were irradiated with 10 MeV protons. The 1-MeV neutron equivalent irradiation doses were 1.6×1014 and 8.5×1013 cm−2 for detectors, and up to 5.0×1014 cm−3 for test diodes. After irradiations, depletion voltages and leakage currents were measured. Czochralski silicon devices proved to be significantly more radiation hard than the reference devices made on traditional detector materials.
Search forBs0→μ+μ−andB0→μ+μ−Decays with CDF II
A search has been performed for B{sub s}{sup 0} {yields} {mu}{sup +}{mu}{sup -} and B{sup 0} {yields} {mu}{sup +}{mu}{sup -} decays using 7 fb{sup -1} of integrated luminosity collected by the CDF II detector at the Fermilab Tevatron collider. The observed number of B{sup 0} candidates is consistent with background-only expectations and yields an upper limit on the branching fraction of {Beta}(B{sup 0} {yields} {mu}{sup +}{mu}{sup -}) < 6.0 x 10{sup -9} at 95% confidence level. We observe an excess of B{sub s}{sup 0} candidates. The probability that the background processes alone could produce such an excess or larger is 0.27%. The probability that the combination of background and the expe…
Measurement of thett¯production cross section inpp¯collisions ats=1.96 TeVusing soft electronb-tagging
The authors present a measurement of the t{bar t} production cross section using events with one charged lepton and jets from p{bar p} collisions at a center-of-mass energy of 1.96 TeV. A b-tagging algorithm based on the probability of displaced tracks coming from the event interaction vertex is applied to identify b quarks from top decay. Using 318 pb{sup -1} of data collected with the CDF II detector, they measure the t{bar t} production cross section in events with at least one restrictive (tight) b-tagged jet and obtain 8.9{sub -1.0}{sup +1.0}(stat.){sub -1.0}{sup +1.1}(syst.) pb. The cross section value assumes a top quark mass of m{sub t} is presented in the paper. This result is cons…