We use 429 fb$^{-1}$ of $e^+e^-$ collision data collected at the $\Upsilon(4S)$ resonance with the BABAR detector to measure the radiative transition rate of $b\rightarrow s\gamma$ with a sum of 38 ...exclusive final states. The inclusive branching fraction with a minimum photon energy of 1.9 GeV is found to be $\mathcal{B}(\bar B \rightarrow X_{s}\gamma)=(3.29\pm 0.19\pm 0.48)\times 10^{-4}$ where the first uncertainty is statistical and the second is systematic. We also measure the first and second moments of the photon energy spectrum and extract the best fit values for the heavy-quark parameters, $m_{b}$ and $\mu_{\pi}^{2}$, in the kinetic and shape function models.
Background radiation measurements at high power research reactors Ashenfelter, J.; Balantekin, B.; Baldenegro, C.X. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
01/2016, Letnik:
806
Journal Article
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Research reactors host a wide range of activities that make use of the intense neutron fluxes generated at these facilities. Recent interest in performing measurements with relatively low event ...rates, e.g. reactor antineutrino detection, at these facilities necessitates a detailed understanding of background radiation fields. Both reactor-correlated and naturally occurring background sources are potentially important, even at levels well below those of importance for typical activities. Here we describe a comprehensive series of background assessments at three high-power research reactors, including γ-ray, neutron, and muon measurements. For each facility we describe the characteristics and identify the sources of the background fields encountered. The general understanding gained of background production mechanisms and their relationship to facility features will prove valuable for the planning of any sensitive measurement conducted therein.
Background Computer-based cognitive rehabilitation is used to improve cognitive functioning after stroke. However, knowledge on adherence rates of stroke patients is limited.
Objective To describe ...stroke patients' adherence with a brain training program using two frequencies of health professionals' supervision.
Methods This study is part of a randomized controlled trial comparing the effect of the brain training program (600 min playtime with weekly supervision) with a passive intervention in patients with self-perceived cognitive impairments after stroke. Patients randomized to the control condition were offered the brain training after the trial and received supervision twice (vs weekly in intervention group). Adherence was determined using data from the study website. Logistic regression analyses were used to examine the impact of supervision on adherence.
Results 53 patients allocated to the intervention group (group S8; 64% male, mean age 59) and 52 patients who were offered the intervention after the trial (group S2; 59% male, mean age 59) started the brain training. The median playtime was 562 min (range 63-1264) in group S8 vs. 193 min (range 27-2162) in group S2 (p < 0.001, Mann Whitney U).
Conclusions The overall adherence of stroke patients with a brain training was low and there are some implications that systematic, regular interaction with a supervisor can increase training adherence of stroke patients with a restitution-focused intervention performed at home.
The PROSPECT and STEREO collaborations present a combined measurement of the pure 235U antineutrino spectrum, without site specific corrections or detector-dependent effects. The spectral ...measurements of the two highest precision experiments at research reactors are found to be compatible with χ2/ndf = 24.1/21, allowing a joint unfolding of the prompt energy measurements into antineutrino energy. This $\bar{ν}_e$ energy spectrum is provided to the community, and an excess of events relative to the Huber model is found in the 5-6 MeV region. When a Gaussian bump is fitted to the excess, the data-model χ2 value is improved, corresponding to a 2.4σ significance.