Development and performance of IR detectors in the 1.5 to 2.4 micrometer region that operate at 240 K

High performance 1.5 to 2.4 micrometers (Hg,Cd)Te photodetectors for operating at 240 K or above are discussed. The detailed characterization of the detector with respect to detector temperature and background flux led to a development of an empirical model for minority carrier trapping. The concept of detective time constant is presented and successfully demonstrated by the four detectors delivered on this contract. An alternative approach is presented with the use of photovoltaic (Hg,Cd)Te detectors

Revisiting Charmless Hadronic B_{u,d} Decays in QCD Factorization

Within the framework of QCD factorization (QCDF), we consider two different types of power correction effects in order to resolve the CP puzzles and rate deficit problems with penguin-dominated two-body decays of B mesons and color-suppressed tree-dominated $\pi^0\pi^0$ and $\rho^0\pi^0$ modes: penguin annihilation and soft corrections to the color-suppressed tree amplitude. We emphasize that the electroweak penguin solution to the $B\to K\pi$ CP puzzle via New Physics is irrelevant for solving the CP and rate puzzles related to tree-dominated decays. While some channels e.g. $K^-\pi^+,K^-\rho^0,\pi^+\pi^-,\rho^\pm\pi^\mp$ need penguin annihilation to induce the correct magnitudes and signs for their CP violation, some other decays such as $B^-\to K^-\pi^0,\pi^-\eta, K^-\eta$ and $\bar B^0\to \bar K^{*0}\eta,\pi^0\pi^0$ require the presence of both power corrections to account for the measured CP asymmetries. In general, QCDF predictions for the branching fractions and direct CP asymmetries of $\bar B\to PP,VP,VV$ decays are in good agreement with experiment. The predictions of pQCD and soft-collinear effective theory are included for comparison.Comment: 51 pages, 1 figur

Fluctuations of Entropy Production in Partially Masked Electric Circuits: Theoretical Analysis

In this work we perform theoretical analysis about a coupled RC circuit with constant driven currents. Starting from stochastic differential equations, where voltages are subject to thermal noises, we derive time-correlation functions, steady-state distributions and transition probabilities of the system. The validity of the fluctuation theorem (FT) is examined for scenarios with complete and incomplete descriptions.Comment: 4 pages, 1 figur

Flavor SU(3) analysis of charmless B->PP decays

We perform a global fits to charmless $B \to PP$ decays which independently constrain the $(\bar\rho,\bar\eta)$ vertex of the unitarity triangle. The fitted amplitudes and phase are used to predict the branching ratios and CP asymmetries of all decay modes, including those of the $B_s$ system. Different schemes of SU(3) breaking in decay amplitude sizes are analyzed. The possibility of having a new physics contribution to $K \pi$ decays is also discussed.Comment: 3 pages, 2 figs. Talk given at EPS-HEP07 To appear in the proceedings, Reference adde

Additive Expression of Consolidated Memory through Drosophila Mushroom Body Subsets

Associative olfactory memory in Drosophila has two components called labile anesthesia-sensitive memory and consolidated anesthesia-resistant memory (ARM). Mushroom body (MB) is a brain region critical for the olfactory memory and comprised of 2000 neurons that can be classified into alphabeta, alpha'beta', and gamma neurons. Previously we demonstrated that two parallel pathways mediated ARM consolidation: the serotonergic dorsal paired medial (DPM)-alphabeta neurons and the octopaminergic anterior paired lateral (APL)-alpha'beta' neurons. This finding prompted us to ask how this composite ARM is retrieved. Here, we showed that blocking the output of alphabeta neurons and that of alpha'beta' neurons each impaired ARM retrieval, and blocking both simultaneously had an additive effect. Knockdown of radish and octbeta2R in alphabeta and alpha'beta' neurons, respectively, impaired ARM. A combinatorial assay of radish mutant background rsh1 and neurotransmission blockade confirmed that ARM retrieved from alpha'beta' neuron output is independent of radish. We identified MBON-beta2beta'2a and MBON-beta'2mp as the MB output neurons downstream of alphabeta and alpha'beta' neurons, respectively, whose glutamatergic transmissions also additively contribute to ARM retrieval. Finally, we showed that alpha'beta' neurons could be functionally subdivided into alpha'beta'm neurons required for ARM retrieval, and alpha'beta'ap neurons required for ARM consolidation. Our work demonstrated that two parallel neural pathways mediating ARM consolidation in Drosophila MB additively contribute to ARM expression during retrieval

Engineering a static verification tool for GPU kernels

We report on practical experiences over the last 2.5 years related to the engineering of GPUVerify, a static verification tool for OpenCL and CUDA GPU kernels, plotting the progress of GPUVerify from a prototype to a fully functional and relatively efficient analysis tool. Our hope is that this experience report will serve the verification community by helping to inform future tooling efforts. © 2014 Springer International Publishing

Perturbative QCD Fragmentation Functions for BcB_c and Bc∗B_c^* Production

The dominant production mechanism for ${\bar b} c$ bound states in high energy processes is the production of a high energy ${\bar b}$ or $c$ quark, followed by its fragmentation into the ${\bar b} c$ state. We calculate the fragmentation functions for the production of the S-wave states $B_c$ and $B_c^*$ to leading order in the QCD coupling constant. The fragmentation probabilities for ${\bar b} \rightarrow B_c$ and ${\bar b} \rightarrow B_c^*$ are approximately $2.2 \times 10^{-4}$ and $3.1 \times 10^{-4}$, while those for $c \rightarrow B_c$ and $c \rightarrow B_c^*$ are smaller by almost two orders of magnitude.Comment: Latex, 12 pages, 3 figures available upon request, NUHEP-TH-93-

Hitting Time of Quantum Walks with Perturbation

The hitting time is the required minimum time for a Markov chain-based walk (classical or quantum) to reach a target state in the state space. We investigate the effect of the perturbation on the hitting time of a quantum walk. We obtain an upper bound for the perturbed quantum walk hitting time by applying Szegedy's work and the perturbation bounds with Weyl's perturbation theorem on classical matrix. Based on the definition of quantum hitting time given in MNRS algorithm, we further compute the delayed perturbed hitting time (DPHT) and delayed perturbed quantum hitting time (DPQHT). We show that the upper bound for DPQHT is actually greater than the difference between the square root of the upper bound for a perturbed random walk and the square root of the lower bound for a random walk.Comment: 9 page