Daniel J. Sperka

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While computer-aided planning of human neurosurgeries is becoming more and more common, animal researchers still largely rely on paper atlases for planning their approach before implanting recording chambers to perform invasive recordings of neural activity, which makes this planning process tedious and error-prone. Here we present SPLASh (Stereotactic(More)
We have used the CLEO-II detector at the Cornell Electron Storage Ring to study the inclusive production of charmonium mesons in a sample of 2.15 million BB events. We nd inclusive branching fractions of ( for B!J==X, (0.340.040.03)% for B! 0 X, and (0.400.060.04)% for B! c1 X. We also nd some evidence for the inclusive production of c2. An(More)
A search has been performed for B(s)(0) → μ+ μ- and B(0) → μ+ μ- decays using 7 fb(-1) of integrated luminosity collected by the CDF II detector at the Fermilab Tevatron collider. The observed number of B(0) candidates is consistent with background-only expectations and yields an upper limit on the branching fraction of B(B(0) → μ+ μ-) < 6.0 × 10(-9) at 95%(More)
We have studied the leptonic decay of the Υ(1S) resonance into tau pairs using the CLEO II detector. A clean sample of tau pair events is identified via events containing two charged particles where exactly one of the particles is an identified electron. We find B(Υ(1S) → ττ) = ( 2.61 ± 0.12 +0.09 −0.13 )
Using a high-statistics sample of data on the (4S) resonance and the nearby continuum collected by the CLEO-II detector 1], we have made preliminary studies of: a) correlations of baryons with leptons produced in (4S) ! B B events, and b) direct production of c baryons in B-decay. We nd evidence that the decay b ! cW ? ; W ? ! cs contributes to B-decays to(More)
We measure the lepton lifetime with + pairs in which one or both of the 's decays to three charged particles. The data were collected with the CLEO II detector operating at the electron-positron collider CESR at energies on and near the (4S). We use displacements of the three-track vertices to determine the lifetime. The result is = 289:0 2:8 4:0 fs.(More)
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