Factorization and resummation for transverse thrust

We analyze transverse thrust in the framework of Soft Collinear Effective Theory and obtain a factorized expression for the cross section that permits resummation of terms enhanced in the dijet limit to arbitrary accuracy. The factorization theorem for this hadron-collider event-shape variable involves collinear emissions at different virtualities and suffers from a collinear anomaly. We compute all its ingredients at the one-loop order, and show that the two-loop input for next-to-next-to-leading logarithmic accuracy can be extracted numerically, from existing fixed-order codes.Comment: 47 pages, 12 figures. v2: journal versio

Electroweak Sudakov effects in W, Z and gamma production at large transverse momentum

We study electroweak Sudakov effects in single W, Z and gamma production at large transverse momentum using Soft Collinear Effective Theory. We present a factorized form of the cross section near the partonic threshold with both QCD and electroweak effects included and compute the electroweak corrections arising at different scales. We analyze their size relative to the QCD corrections as well as the impact of strong-electroweak mixing terms. Numerical results for the vector-boson cross sections at the Large Hadron Collider are presented.Comment: 14 pages, 5 figures. v2: Minor changes, references added. Journal versio

Addendum: Electroweak Sudakov effects in W, Z and gamma production at large transverse momentum

In this addendum to Phys. Rev. D 88, no. 1, 013009 (2013), we give results for the electroweak Sudakov corrections in gauge-boson production at large transverse momentum p_T at proton colliders. In order for the results to be easily usable, we provide a simple and accurate parameterization of the corrections as a function of p_T and the center-of-mass energy \sqrt{s}. Additionally, we also discuss the dependence of the electroweak corrections on the rapidity of the produced boson, and comment on the complications that arise in the photon-production case due to isolation requirementsComment: 4 pages, 4 figure

Investigation of flow structures involved in sound generation by two- and three-dimensional cavity flows

Proper Orthogonal Decomposition and Stochastic Estimation are combined to shed some light on the link between organized flow structures and noise generation by turbulent flows. Proper Orthogonal Decomposition (POD) is firstly used to extract selected flow events. Based on the knowledge of these structures, the Quadratic Stochastic Estimation of the acoustic pressure field is secondly performed. Both procedures are successively applied to two- and three-dimensional numerical databases of a flow over a cavity. It is demonstrated that POD can extract selected aerodynamic events which can be associated with selected frequencies in the acoustic spectra. Reconstructed acoustic fields also indicate the aerodynamic events which are responsible of the main energy of the noise emission. Such mathematical tools offer new perspectives in analysing flow structures involved in sound generation by turbulent flows and in the experimental design of a flow control strategy

Interpolating sequences for weighted Bergman spaces of the ball

Let $B_{\alpha}^{p}$ be the space of $f$ holomorphic in the unit ball of $\Bbb C^n$ such that $(1-|z|^2)^\alpha f(z) \in L^p$, where $0<p\leq\infty$, $\alpha\geq -1/p$ (weighted Bergman space). In this paper we study the interpolating sequences for various $B_{\alpha}^{p}$. The limiting cases $\alpha=-1/p$ and $p=\infty$ are respectively the Hardy spaces $H^p$ and $A^{-\alpha}$, the holomorphic functions with polynomial growth of order $\alpha$, which have generated particular interest. In \S 1 we first collect some definitions and well-known facts about weighted Bergman spaces and then introduce the natural interpolation problem, along with some basic properties. In \S 2 we describe in terms of $\alpha$ and $p$ the inclusions between $B_{\alpha}^{p}$ spaces, and in \S 3 we show that most of these inclusions also hold for the corresponding spaces of interpolating sequences. \S 4 is devoted to sufficient conditions for a sequence to be $B_{\alpha}^{p}$-interpolating, expressed in the same terms as the conditions given in previous works of Thomas for the Hardy spaces and Massaneda for $A^{-\alpha}$. In particular we show, under some restrictions on $\alpha$ and $p$, that finite unions of $B_{\alpha}^{p}$-interpolating sequences coincide with finite unions of separated sequences. In his article in Inventiones, Seip implicitly gives a characterization of interpolating sequences for all weighted Bergman spaces in the disk. We spell out the details for the reader's convenience in an appendix (\S 5)

A New Method for Generation of Soundings from Phase-Difference Measurements

A desirable feature of bathymetric sonar systems is the production of statistically independent soundings allowing a system to achieve its full capability in resolution and object detection. Moreover gridding algorithms such as the Combined Uncertainty Bathymetric Estimator (CUBE) rely on the statistical independence of soundings to properly estimate depth and discriminate outliers. Common methods of filtering to mitigate uncertainty in the signal processing of both multibeam and phase-differencing sidescan systems (curve fitting in zero-crossing detections and differential phase filtering respectively) can produce correlated soundings. Here we propose an alternative method for the generation of soundings from differential phase measurements made by either sonar type to produce statistically independent soundings. The method extracts individual, non-overlapping and unfiltered, phase-difference measurements (from either sonar type) converting these to sonar-relative receive angle, estimates their uncertainty, fixes the desired depth uncertainty level and combines these individual measurements into an uncertainty-weighted mean to achieve the desired depth uncertainty, and no more. When the signal to noise ratio is sufficiently high such that the desired depth uncertainty is achieved with an individual measurement, bathymetric estimates are produced at the sonar’s full resolution capability. When multiple measurements are required, the filtering automatically adjusts to maintain the desired uncertainty level, degrading the resolution only as necessary. Because no two measurements contribute to a single reported sounding, the resulting estimated soundings are statistically independent and therefore better resolve adjacent objects, increase object detectability and are more suitable for statistical gridding methodologies