210 research outputs found
Challenges and concepts for design of an interaction region with push-pull arrangement of detectors - an interface document
Search for time-dependent B0s - B0s-bar oscillations using a vertex charge dipole technique
We report a search for B0s - B0s-bar oscillations using a sample of 400,000
hadronic Z0 decays collected by the SLD experiment. The analysis takes
advantage of the electron beam polarization as well as information from the
hemisphere opposite that of the reconstructed B decay to tag the B production
flavor. The excellent resolution provided by the pixel CCD vertex detector is
exploited to cleanly reconstruct both B and cascade D decay vertices, and tag
the B decay flavor from the charge difference between them. We exclude the
following values of the B0s - B0s-bar oscillation frequency: Delta m_s < 4.9
ps-1 and 7.9 < Delta m_s < 10.3 ps-1 at the 95% confidence level.Comment: 18 pages, 3 figures, replaced by version accepted for publication in
Phys.Rev.D; results differ slightly from first versio
Synhthesis, x-ray crystal structure, and magnetic studies of a bis-copper(II) complex of a C-spiro binucleating linear octadentate ligand
A study of Channeling, Volume Reflection and Volume Capture of 3.35-14.0 GeV Electrons in a bent Silicon Crystal
We present the experimental data and analysis of experiments conducted at SLAC National Accelerator
Laboratory investigating the processes of channeling, volume-reflection and volume-capture along the (111)
plane in a strongly bent quasi-mosaic silicon crystal. These phenomena were investigated at 5 energies: 3.35,
4.2, 6.3, 10.5 and 14.0 GeV with a crystal with bending radius of 0.15m, corresponding to curvatures of
0.070, 0.088, 0.13, 0.22 and 0.29 times the critical curvature respectively. Based on the parameters of fitting
functions we have extracted important parameters describing the channeling process such as the dechanneling
length, the angle of volume reflection, the surface transmission and the widths of the distribution of channeled
particles parallel and orthogonal to the plane
Buccal mucosa graft for simultaneous correction of severe chordee and urethroplasty as a one-stage repair of scrotal hypospadias (watch technique)
Direct measurement of geometric and resistive wakefields in tapered collimators for the International Linear Collider
Precise collimation of the beam halo is required in the International Linear Collider (ILC) to prevent beam losses near the interaction region that could cause unacceptable backgrounds for the physics detector. The necessarily small apertures of the collimators lead to transverse wakefields that may result in beam deflections and increased emittance. A set of collimator wakefield measurements has previously been performed in the ASSET region of the SLAC Linac. We report on the next phase of this programme, which is carried out at the recently commissioned End Station A (ESA) test facility at SLAC. Measurements of resistive and geometric wakefields using tapered collimators are compared with model predictions from MAFIA and GdfidL and with analytic calculations
Direct Measurement of Geometric and Resistive Wakefields in Tapered Collimators for the International Linear Collider
Proper land use for heavy metal-polluted soil based on enzyme activity analysis around a Pb-Zn mine in Feng County, China
Enzymes in the soil are useful for assessing heavy metal soil pollution. We analyzed the activity of a number of enzymes, including urease, protease, catalase, and alkaline phosphatase, in three types of land (farmland, woodland, and grassland) to evaluate soil pollution by heavy metals (Pb, Zn, and Cd). Our results showed that the tested soil was polluted by a combination of Pb, Zn, and Cd, but the primary pollutant was Cd. An ecological dose analysis demonstrated that urease was the most sensitive enzyme to Pb and Cd in the farmland, and catalase and phosphatase were the most sensitive enzymes to Pb, Zn, and Cd in the woodland and grassland. The ecological risk of Cd (E (Cd) ) was the smallest in all three types of land, suggesting that Cd was the major metal inhibiting enzyme activity. Electrical conductivity (EC) was shown to be a negative regulator, while nitrogen, phosphorus, and clay contents were positive regulators of soil enzyme activity. The total enzyme index (TEI) inhibition rates in the woodland were 22.2 and 38.6% under moderate and heavy pollution, respectively, which were lower than those of the other two types of land. Therefore, woodlands might be the optimum land use choice in relieving heavy metal pollution. Taken together, this study identified the key metal pollutant inhibiting soil enzyme activity and suitable land use patterns around typical metal mine. These results provide possible improvement strategies to the phytomanagement of metal-contaminated land around world
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