Constrained Molecular Dynamics II: a N-body approach to nuclear systems

In this work we illustrate the basic development of the constrained molecular dynamics applied to the N-body problem in nuclear physics. The heavy computational taskes related to quantum effects, to the presence of the "hard core" repulsive interaction have been worked out by defining a set of transformations based on the concept of impulsive forces. In particular in the implemented version II of the Constrained Molecular Dynamics model the problem related to the non conservation of the total angular momentum has been solved. This problem can affect others semiclassical microscopic approaches as due to the "hard core" repulsive interaction or to the use of stochastic forces. The effect of the restored conservation law on the fusion cross section for 40Ca+40Ca system is also briefly discussed.Comment: Tex version 3.1459 (Web2C 7.3.1);main text+fig.cap in .tex 13 page; +4 figures .ps;the order and the numerical label of the figure files reflect the figure numbers in the main tex and captions, Submited to Journal of computational physic

Real-time extraction of growth rates from rotating substrates during molecular-beam epitaxy

We present a method for measuring molecular‐beam epitaxy growth rates in near real‐time on rotating substrates. This is done by digitizing a video image of the reflection high‐energy electron diffraction screen, automatically tracking and measuring the specular spot width, and using numerical techniques to filter the resulting signal. The digitization and image and signal processing take approximately 0.4 s to accomplish, so this technique offers the molecular‐beam epitaxy grower the ability to actively adjust growth times in order to deposit a desired layer thickness. The measurement has a demonstrated precision of approximately 2%, which is sufficient to allow active control of epilayer thickness by counting monolayers as they are deposited. When postgrowth techniques, such as frequency domain analysis, are also used, the reflection high‐energy electron diffraction measurement of layer thickness on rotating substrates improves to a precision of better than 1%. Since all of the components in the system described are commercially available, duplication is straightforward

Dihadron Production at LHC: BFKL Predictions for Cross Sections and Azimuthal Correlations

A study of the inclusive production of a pair of hadrons (a "dihadron" system), having high transverse momenta and separated by a large interval of rapidity, is presented. This process has much in common with the widely discussed Mueller--Navelet jet production and can be also used to access the BFKL dynamics at proton colliders. Large contributions enhanced by logarithms of energy can be resummed in perturbation theory within the BFKL formalism in the next-to-leading logarithmic accuracy. The experimental study of dihadron production would provide with an additional clear channel to test the BFKL dynamics. The first theoretical predictions for cross sections and azimuthal angle correlations of the two hadrons produced with LHC kinematics are presented.Comment: 4 pages, 2 figures; presented by F.G. Celiberto at "Diffraction 2016", International Workshop on Diffraction in High-Energy Physics, Acireale (Catania, Sicily), Sept. 2-8, 2016; to be published in the conference proceedings by AI

Lessons from Flanders: drivers & pitfalls of cooperation on a business park

For almost ten years several companies located in De Zaubeek Business Park in Flanders have been collaborating with the goal of creating a more sustainable industrial zone. Many initiatives have been developed in this business park, many successful, but some clearly pointed to constraints that require action beyond the reach of the companies or the business association. The former chairman of the association has been involved in several of these initiatives and we asked him to tell his story