Holographic Technidilaton and LHC searches

We analyze in detail the phenomenology of a model of dynamical electroweak symmetry breaking inspired by walking technicolor, by using the techniques of the bottom-up approach to holography. The model admits a light composite scalar state, the dilaton, in the spectrum. We focus on regions of parameter space for which the mass of such dilaton is 125 GeV, and for which the bounds on the precision electroweak parameter S are satisfied. This requires that the next-to-lightest composite state is the techni-rho meson, with a mass larger than 2.3 TeV. We compute the couplings controlling the decay rates of the dilaton to two photons and to two (real or virtual) Z and W bosons. For generic choices of the parameters, we find a suppression of the decay into heavy gauge bosons, in respect to the analog decay of the standard-model Higgs. We find a dramatic effect on the decay into photons, which can be both strongly suppressed or strongly enhanced, the latter case corresponding to the large-N regime of the dual theory. There is a correlation between this decay rate of the dilaton into photons and the mass splitting between the techni-rho meson and its axial-vector partner: if the decay is enhanced in respect to the standard-model case, then the heavy spin-1 resonances are nearly degenerate in mass, otherwise their separation in mass is comparable to the mass scale itself.Comment: Very minor typos corrected. References adde

Microwave Spectroscopy

Contains reports on three research projects

Listening to mental health crisis needs at scale: using Natural Language Processing to understand and evaluate a mental health crisis text messaging service

The current mental health crisis is a growing public health issue requiring a large-scale response that cannot be met with traditional services alone. Digital support tools are proliferating, yet most are not systematically evaluated, and we know little about their users and their needs. Shout is a free mental health text messaging service run by the charity Mental Health Innovations, which provides support for individuals in the UK experiencing mental or emotional distress and seeking help. Here we study a large data set of anonymised text message conversations and post-conversation surveys compiled through Shout. This data provides an opportunity to hear at scale from those experiencing distress; to better understand mental health needs for people not using traditional mental health services; and to evaluate the impact of a novel form of crisis support. We use natural language processing (NLP) to assess the adherence of volunteers to conversation techniques and formats, and to gain insight into demographic user groups and their behavioural expressions of distress. Our textual analyses achieve accurate classification of conversation stages (weighted accuracy = 88%), behaviours (1-hamming loss = 95%) and texter demographics (weighted accuracy = 96%), exemplifying how the application of NLP to frontline mental health data sets can aid with post-hoc analysis and evaluation of quality of service provision in digital mental health services

Volume CVI, Number 19, April 14, 1989

Institute of High Performance Computing, IHPC;University of Perugia, Italy;University of Calgary, Canada;University of Minnesota, MN, USA;Queen's University BelfastInternational Conference on Computational Science and Its Applications - ICCSA 2005 -- 9 May 2005 through 12 May 2005 -- 65625Discrete mathematics is one of the very basic mathematics courses in computer engineering (CE) and/or computer science (CS) departments. This course covers almost all of the basic concepts for many other courses in the curriculum and requires active learning of students. For this purpose, especially "propositions" concept, which cannot be understood well in prior years, should be covered with every detail. Previous studies show that learning by entertaining activities and competition has positive effect on student motivation. In this study, an Internet-based Discrete Mathematics Package (DMP) for "propositions" that can work in mobile devices and encourages competitive learning between students has been developed within related literature. © Springer-Verlag Berlin Heidelberg 2005

Portmanteau tests for linearity of Stationary Time Series

This paper considers the problem of testing for linearity of stationary time series. Portmanteau tests are discussed which are based on generalized correlations of residuals from a linear model (that is, autocorrelations and cross-correlations of different powers of the residuals). The finite-sample properties of the tests are assessed by means of Monte Carlo experiments. The tests are applied to 100 time series of stock returns

Ab initio calculations of stationary points on the benzene-Ar and p-difluorobenzene-Ar potential energy surfaces: barriers to bound orbiting states

The potential energy surfaces of the van der Waals complexes benzene–Ar and p-difluorobenzene– Ar have been investigated at the second-order Møller–Plesset (MP2) level of theory with the aug-cc-pVDZ basis set. Calculations were performed with unconstrained geometry optimization for all stationary points. This study has been performed to elucidate the nature of a conflict between experimental results from dispersed fluorescence and velocity map imaging (VMI). The inconsistency is that spectra for levels of p-difluorobenzene–Ar and –Kr below the dissociation thresholds determined by VMI show bands where free p-difluorobenzene emits, suggesting that dissociation is occurring. We proposed that the bands observed in the dispersed fluorescence spectra are due to emission from states in which the rare gas atom orbits the aromatic chromophore; these states are populated by intramolecular vibrational redistribution from the initially excited level [S. M. Bellm, R. J. Moulds, and W. D. Lawrance, J. Chem. Phys. 115, 10709 (2001)]. To test this proposition, stationary points have been located on both the benzene–Ar and p-difluorobenzene–Ar potential energy surfaces (PESs) to determine the barriers to this orbiting motion. Comparison with previous single point CCSD(T) calculations of the benzene–Ar PES has been used to determine the amount by which the barriers are overestimated at the MP2 level. As there is little difference in the comparable regions of the benzene–Ar and p-difluorobenzene–Ar PESs, the overestimation is expected to be similar for p-difluorobenzene–Ar. Allowing for this overestimation gives the barrier to movement of the Ar atom around the pDFB ring via the valley between the H atoms as [less than or equal to] 204 cm⁻¹ in So (including zero point energy). From the estimated change upon electronic excitation, the corresponding barrier in S1 is estimated to be [less than or equal to] 225 cm⁻¹. This barrier is less than the 240 cm⁻¹ energy of 30², the vibrational level for which the anomalous "free p-difluorobenzene" bands were observed in dispersed fluorescence from p-difluorobenzene–Ar, supporting our hypothesis for the origin of these bands.Rebecca J. Moulds, Mark A. Buntine and Warren D. Lawranc

Online Informative Path Planning for Active Information Gathering of a 3D Surface

This paper presents an online informative path planning approach for active information gathering on three-dimensional surfaces using aerial robots. Most existing works on surface inspection focus on planning a path offline that can provide full coverage of the surface, which inherently assumes the surface information is uniformly distributed hence ignoring potential spatial correlations of the information field. In this paper, we utilize manifold Gaussian processes (mGPs) with geodesic kernel functions for mapping surface information fields and plan informative paths online in a receding horizon manner. Our approach actively plans information-gathering paths based on recent observations that respect dynamic constraints of the vehicle and a total flight time budget. We provide planning results for simulated temperature modeling for simple and complex 3D surface geometries (a cylinder and an aircraft model). We demonstrate that our informative planning method outperforms traditional approaches such as 3D coverage planning and random exploration, both in reconstruction error and information-theoretic metrics. We also show that by taking spatial correlations of the information field into planning using mGPs, the information gathering efficiency is significantly improved.Comment: 7 pages, 7 figures, to be published in 2021 IEEE International Conference on Robotics and Automation (ICRA

A "circularisation" method to repair deformations and determine the centre of velocity map images

A problem besetting the analysis of velocity map images, particularly those of photoelectrons, is the presence of distortions that cause the features in the image to deviate from circularity, leading to a loss of resolution in the spectrum extracted. A method is presented to repair such distortions based on fitting the angular behaviour of each of the ring structures to a trigonometric expansion. The repair function allows the intensity at any value of radius and angle to be mapped to a new position that removes the distortion and returns the features to circular. While the method relies on the analysis of the structure in an image, it could also be applied to determine the “repair function” using a calibration image (or series of images) for the experiment. Once the image has been circularised it can be processed by any of the approaches that have been developed for that purpose. The analysis also enables the image centre to be determined with high accuracy. The fitting method utilises an inverse Abel transformation of the image in polar coordinates as a means to reshape the image into a series of spectral features in order to determine the radial position of features at each angle. Although the velocity distribution is not in general spherically symmetric and so this is not a mathematically correct means to extract the velocity distribution, the feature positions are accurately reproduced in the resulting spectrum while the intensity and anisotropy parameters can be remarkably close to those obtained using the proper inverse Abel transformation of the imageS.T.G. acknowledges support by the Australian Research Council Discovery Project Grant No. DP160102585