T-odd correlations in charged Kl4 decays

We analyse the sensitivity to physics beyond the SM of T-odd correlations in $K_{\ell 4}$ decays, which do not involve the lepton polarization. We show that a combined analysis of $K^+_{\mu 4}$ and $K^-_{\mu 4}$ decays can lead to new constraints about CP violation in $\Delta S=1$ charged-current interactions, complementary to those obtained from the transverse muon polarization in $K_{\mu 3}$ and of comparable accuracy.Comment: 6 pages (LaTeX

Constrained Cluster Parameters from Sunyaev-Zel'dovich Observations

Near-future SZ surveys such as ACT, SPT, APEX, and Planck will find thousands of galaxy clusters. Multi-frequency arcminute-resolution SZ observations can, in principle, determine each cluster's gas temperature (T_e), bulk velocity (v_pec), and optical depth (tau). However, the frequency bands and detector sensitivity employed by upcoming surveys will generally not be sufficient to disentangle the degeneracy between these three cluster parameters, even in the absence of SZ signal contamination from point sources and imperfect primary microwave background subtraction. Assuming contaminants can be removed, we find that near-future SZ surveys will be able to constrain well two cluster gas parameters that are linear combinations of tau*T_e, tau*v_z, and tau*T_e^2. Because the SZ intensity shift is nearly a linear function of tau*T_e, tau*v_z, and tau*T_e^2, a correspondence exists between the two effective gas parameters that SZ surveys can constrain and simple line-of-sight integrals through the three dimensional cluster. We illustrate the parameter constraints and correspondence to line-of-sight integrals using 3D Nbody + hydro cluster simulations and a Markov chain Monte Carlo method. We show that adding an independent T_e measurement to upcoming SZ data breaks the parameter degeneracy. The cluster effective velocity thus constrained is approximately the optical-depth-weighted velocity integrated along the cluster line of sight. A temperature prior with an error as large as 2 keV still gives bulk velocity errors < 100 km/sec, even for a more typical cluster with an electron temperature of 3 keV, for ACT-like SZ observations in the absence of signal contamination. The Markov chain constraints on v_pec and tau are more encouraging and likely more accurate than those obtained from Fisher matrices.Comment: 31 pages, 15 figures. Typo corrected; accepted by Ap

Minimally invasive endoscopic therapies for gastro-oesophageal reflux disease

The prevalence of the gastro-oesophageal reflux disease (GORD) in the western world is increasing. Uncontrolled GORD can lead to harmful long-term sequela such as oesophagitis, stricture formation, Barrett's oesophagus and oesophageal adenocarcinoma. Moreover, GORD has been shown to negatively impact quality of life. The current treatment paradigm for GORD consists of lifestyle modification, pharmacological control of gastric acid secretion or antireflux surgery. In recent years, several minimally invasive antireflux endoscopic therapies (ARET) have been developed which may play a role in bridging the unmet therapeutic gap between the medical and surgical treatment options. To ensure optimal patient outcomes following ARET, considered patient selection is crucial, which requires a mechanistic understanding of individual ARET options. Here, we will discuss the differences between ARETs along with an overview of the current evidence base. We also outline future research priorities that will help refine the future role of ARET

Shock Breakout in Core-Collapse Supernovae and its Neutrino Signature

(Abridged) We present results from dynamical models of core-collapse supernovae in one spatial dimension, employing a newly-developed Boltzmann neutrino radiation transport algorithm, coupled to Lagrangean hydrodynamics and a consistent high-density nuclear equation of state. We focus on shock breakout and its neutrino signature and follow the dynamical evolution of the cores of 11 M_sun, 15 M_sun, and 20 M_sun progenitors through collapse and the first 250 milliseconds after bounce. We examine the effects on the emergent neutrino spectra, light curves, and mix of species of artificial opacity changes, the number of energy groups, the weak magnetism/recoil corrections, nucleon-nucleon bremsstrahlung, neutrino-electron scattering, and the compressibility of nuclear matter. Furthermore, we present the first high-resolution look at the angular distribution of the neutrino radiation field both in the semi-transparent regime and at large radii and explore the accuracy with which our tangent-ray method tracks the free propagation of a pulse of radiation in a near vacuum. Finally, we fold the emergent neutrino spectra with the efficiencies and detection processes for a selection of modern underground neutrino observatories and argue that the prompt electron-neutrino breakout burst from the next galactic supernova is in principle observable and usefully diagnostic of fundamental collapse/supernova behavior. Though we are not in this study focusing on the supernova mechanism per se, our simulations support the theoretical conclusion (already reached by others) that spherical (1D) supernovae do not explode when good physics and transport methods are employed.Comment: 16 emulateapj pages, plus 24 postscript figures, accepted to The Astrophysical Journal; text revised; neutrino oscillation section expanded; Fig. 22 correcte

Azimuthal Correlation in Lepton-Hadron Scattering via Charged Weak-Current Processes

We consider the azimuthal correlation of the final-state particles in charged weak-current processes. This correlation provides a test of perturbative quantum chromodynamics. The azimuthal asymmetry is large in the semi-inclusive processes in which we identify a final-state hadron, say, a charged pion compared to that in the inclusive processes in which we do not identify final-state particles and use only the calorimetric information. In semi-inclusive processes the azimuthal asymmetry is more conspicuous when the incident lepton is an antineutrino or a positron than when the incident lepton is a neutrino or an electron. We analyze all the possible charged weak-current processes and study the quantitative aspects of each process. We also compare this result to the ep scattering with a photon exchange.Comment: 25 pages, 2 Postscript figures, uses RevTeX, fixes.st

Effects of Chromate and Chromate Conversion Coatings on Corrosion of Aluminum Alloy 2024-T3

Various effects of chromate conversion coatings (CCCs) and chromate in solution on the corrosion of AA2024-T3 and pure Al are studied in this work. Raman spectroscopy was used to investigate the nature of chromate in CCCs through a comparison with the spectra of known standards and artificial Cr(III)/Cr(VI) mixed oxides. Chromate was shown to be released from CCCs and to migrate to and protect a nearby, uncoated area in the artificial scratch cell. However, experiments investigating the effect of chromate in solution on anodic dissolution kinetics under potentiostatic control indicated that large chromate concentrations were needed to have an effect.This work was supported by Major H. DeLong at the United States Air Force Office of Scientific Research under contracts F49620-96-1-0479 and F49620-96-0042

Z decays into light gluinos: a calculation based on unitarity

The Z boson can decay to a pair of light gluinos through loop-mediated processes. Based on unitarity of the S-matrix, the imaginary part of the decay amplitude is computed in the presence of a light bottom squark. This imaginary part can provide useful information on the full amplitude. Implications are discussed for a recently proposed light gluino and light bottom squark scenario.Comment: 19 pages, LaTeX, 3 figures, submitted to Phys. Rev.

Developments in Rare Kaon Decay Physics

We review the current status of the field of rare kaon decays. The study of rare kaon decays has played a key role in the development of the standard model, and the field continues to have significant impact. The two areas of greatest import are the search for physics beyond the standard model and the determination of fundamental standard-model parameters. Due to the exquisite sensitivity of rare kaon decay experiments, searches for new physics can probe very high mass scales. Studies of the k->pnn modes in particular, where the first event has recently been seen, will permit tests of the standard-model picture of quark mixing and CP violation.Comment: One major revision to the text is the branching ratio of KL->ppg, based on a new result from KTeV. Several references were updated, with minor modifications to the text. A total of 48 pages, with 28 figures, in LaTeX; to be published in the Annual Review of Nuclear and Particle Science, Vol. 50, December 200