NLO corrections to differential cross sections for pseudo-scalar Higgs boson production

We have computed the full next-to-leading (NLO) QCD corrections to the differential distributions $d^2\sigma/(dp_T~dy)$ for pseudo-scalar Higgs (A) production at large hadron colliders. This calculation has been carried out using the effective Lagrangian approach which is valid as long as the mass of the pseudo-scalar Higgs boson $m_{\rm A}$ and its transverse momentum $p_T$ do not exceed the top-quark mass $m_t$. The shape of the distributions hardly differ from those obtained for scalar Higgs (H) production because, apart from the overall coupling constant and mass, there are only small differences between the partonic differential distributions for scalar and pseudo-scalar production. Therefore there are only differences in the magnitudes of the hadronic differential distributions which can be mainly attributed to the unknown mixing angle $\beta$ describing the pseudo-scalar Higgs coupling to the top quarks.Comment: 9 pages, LaTeX, 3 Postscript figures In the previous version we have forgotten to include contributions which arrise from interferences between graphs containing vertices corresponding to the operator $O_2(x)$ in Eq. (3) with graphs originating from the operator $O_1(x)$. These interferences occur because of the prescription for the Levi-Civita tensor given in our paper. These extra contributions are added to Eqs. (19) and (20). Numerically they are completely negligible so that the figures are not altere

Recent results of H-mode studies on asdex

In a comparative study of various confinement regimes the H-mode demonstrated the best performance. Confinement enhancement factors (above ITER 89-P L-mode scaling) in the range of 1.6 fH 2.8 have been achieved with values depending on the divertor configuration, the wall condition, ELM behaviour and the plasma ion spicies. Long-pulse H-phases, withELMs, of up to 3.5s with constant confinement time, recycling and impurity characteristics are archived. H* -mode operation is possible without a loss of current scaling at qa values as low as 2.2. The B-limit is the same with and without ELMs. Murakami parameters are similar in H-and L-modes

Internal avalanches in a pile of superconducting vortices

Using an array of miniature Hall probes, we monitored the spatiotemporal variation of the internal magnetic induction in a superconducting niobium sample during a slow sweep of external magnetic field. We found that a sizable fraction of the increase in the local vortex population occurs in abrupt jumps. The size distribution of these avalanches presents a power-law collapse on a limited range. In contrast, at low temperatures and low fields, huge avalanches with a typical size occur and the system does not display a well-defined macroscopic critical current.Comment: 5 pages including 5 figure

On the variation of the gauge couplings during inflation

It is shown that the evolution of the (Abelian) gauge coupling during an inflationary phase of de Sitter type drives the growth of the two-point function of the magnetic inhomogeneities. After examining the constraints on the variation of the gauge coupling arising in a standard model of inflationary and post-inflationary evolution, magnetohydrodynamical equations are generalized to the case of time evolving gauge coupling. It is argued that large scale magnetic fields can be copiously generated. Other possible implications of the model are outlined.Comment: 5 pages in RevTex style, one figur

Adjustment to colostomy: stoma acceptance, stoma care self-efficacy and interpersonal relationships

‘The definitive version is available at www.blackwell-synergy.com.’ Copyright Blackwell Publishing. DOI: 10.1111/j.1365-2648.2007.04446.xThis paper is a report of a study to examine adjustment and its relationship with stoma acceptance and social interaction, and the link between stoma care self-efficacy and adjustment in the presence of acceptance and social interactions.Peer reviewe

Hard Scattering Factorization from Effective Field Theory

In this paper we show how gauge symmetries in an effective theory can be used to simplify proofs of factorization formulae in highly energetic hadronic processes. We use the soft-collinear effective theory, generalized to deal with back-to-back jets of collinear particles. Our proofs do not depend on the choice of a particular gauge, and the formalism is applicable to both exclusive and inclusive factorization. As examples we treat the pi-gamma form factor (gamma gamma* -> pi^0), light meson form factors (gamma* M -> M), as well as deep inelastic scattering (e- p -> e- X), Drell-Yan (p pbar -> X l+ l-), and deeply virtual Compton scattering (gamma* p -> gamma(*) p).Comment: 35 pages, 4 figures, typos corrected, journal versio

Soft, collinear and non-relativistic modes in radiative decays of very heavy quarkonium

We analyze the end-point region of the photon spectrum in semi-inclusive radiative decays of very heavy quarkonium (m alpha_s^2 >> Lambda_QCD). We discuss the interplay of the scales arising in the Soft-Collinear Effective Theory, m, m(1-z)^{1/2} and m(1-z) for z close to 1, with the scales of heavy quarkonium systems in the weak coupling regime, m, m alpha_s and m alpha_s^2. For 1-z \sim alpha_s^2 only collinear and (ultra)soft modes are seen to be relevant, but the recently discovered soft-collinear modes show up for 1-z << alpha_s^2. The S- and P-wave octet shape functions are calculated. When they are included in the analysis of the photon spectrum of the Upsilon (1S) system, the agreement with data in the end-point region becomes excellent. The NRQCD matrix elements and are also obtained.Comment: Revtex, 11 pages, 6 figures. Minor improvements and references added. Journal versio

Sedimentation processes in a coral reef embayment : Hanalei Bay, Kauai

This paper is not subject to U.S. copyright. The definitive version was published in Marine Geology 264 (2009): 140-151, doi:10.1016/j.margeo.2009.05.002.Oceanographic measurements and sediment samples were collected during the summer of 2006 as part of a multi-year study of coastal circulation and the fate of terrigenous sediment on coral reefs in Hanalei Bay, Kauai. The goal of this study was to better understand sediment dynamics in a coral reef-lined embayment where winds, ocean surface waves, and river floods are important processes. During a summer period that was marked by two wave events and one river flood, we documented significant differences in sediment trap collection rates and the composition, grain size, and magnitude of sediment transported in the bay. Sediment trap collection rates were well correlated with combined wave-current near-bed shear stresses during the non-flood periods but were not correlated during the flood. The flood's delivery of fine-grained sediment to the bay initially caused high turbidity and sediment collection rates off the river mouth but the plume dispersed relatively quickly. Over the next month, the flood deposit was reworked by mild waves and currents and the fine-grained terrestrial sediment was advected around the bay and collected in sediment traps away from the river mouth, long after the turbid surface plume was gone. The reworked flood deposits, due to their longer duration of influence and proximity to the seabed, appear to pose a greater long-term impact to benthic coral reef communities than the flood plumes themselves. The results presented here display how spatial and temporal differences in hydrodynamic processes, which result from variations in reef morphology and orientation, cause substantial variations in the deposition, residence time, resuspension, and advection of both reef-derived and fluvial sediment over relatively short spatial scales in a coral reef embayment

HI Clouds Beyond the Galactic Disk

Recent observations in the 21cm line with the Green Bank Telescope have changed our view of the neutral interstellar medium (ISM) in several ways. The new data show that in the inner parts of the Milky Way the disk-halo interface is composed of many discrete HI clouds. The clouds lie in a layer more than one kpc thick and follow Galactic rotation. Their origin and evolution is unknown. In the outer Galaxy, the new data show that the high-velocity cloud Complex H is likely a satellite on a retrograde orbit interacting with some extended component of the Milky Way's ISM. These observations place new constraints on models of the ISM and are directly related to the work of Don Cox and Ron Reynolds.Comment: 8 pages includes 2 figures. To appear in "How Does the Galaxy Work?", eds. E.J. Alfaro, E. Perez, & J. Franco, Kluwer, Proceedings of a Conference held 23-27 June 2003 in Granada, Spai

Machine Learning in Automated Text Categorization

The automated categorization (or classification) of texts into predefined categories has witnessed a booming interest in the last ten years, due to the increased availability of documents in digital form and the ensuing need to organize them. In the research community the dominant approach to this problem is based on machine learning techniques: a general inductive process automatically builds a classifier by learning, from a set of preclassified documents, the characteristics of the categories. The advantages of this approach over the knowledge engineering approach (consisting in the manual definition of a classifier by domain experts) are a very good effectiveness, considerable savings in terms of expert manpower, and straightforward portability to different domains. This survey discusses the main approaches to text categorization that fall within the machine learning paradigm. We will discuss in detail issues pertaining to three different problems, namely document representation, classifier construction, and classifier evaluation.Comment: Accepted for publication on ACM Computing Survey