Collider Signatures of the N=3 Lee-Wick Standard Model

Inspired by the Lee-Wick higher-derivative approach to quantum field theory, Grinstein, O'Connell, and Wise have illustrated the utility of introducing into the Standard Model negative-norm states that cancel quadratic divergences in loop diagrams, thus posing a potential resolution of the hierarchy problem. Subsequent work has shown that consistency with electroweak precision parameters requires many of the partner states to be too massive to be detected at the LHC. We consider the phenomenology of a yet-higher derivative theory that exhibits three poles in its bare propagators (hence N=3), whose states alternate in norm. We examine the interference effects of W boson partners on LHC scattering cross sections, and find that the N=3 LWSM already makes verifiable predictions at 10 fb^(-1) of integrated luminosity.Comment: 15 pages, 4 PDF figures. Version accepted for publication by JHE

Cardiorespiratory Fitness Modulates The Acute Flow-Mediated Dilation Response Following High-Intensity But Not Moderate-Intensity Exercise In Elderly Men.

Impaired endothelial function is observed with ageing and with low cardiorespiratory fitness (VO2peak) whilst improvements in both are suggested to be reliant on higher-intensity exercise in the elderly. This may be due to the flow-mediated dilation (FMD) response to acute exercise of varying intensity. We examined the hypothesis that exercise-intensity alters the FMD response in healthy elderly adults, and would be modulated by VO2peak Forty-seven elderly men were stratified into lower- (VO2peak = 24.3±2.9 ml.kg(-1)min(-1), n=27) and higher-fit groups (VO2peak = 35.4±5.5 ml.kg(-1)min(-1), n=20) after a test of cycling peak power output (PPO). In randomised order, participants undertook 27 min moderate-intensity continuous (MICE; 40% PPO) or high-intensity interval cycling exercise (HIIE; 70% PPO), or no-exercise control. Brachial FMD was assessed at rest, 10 and 60 min after exercise. In control, FMD reduced in both groups (P=0.05). FMD increased after MICE in both groups [increase of 0.86 % (95% CI, 0.17 to 1.56), P=0.01], and normalised after 60 min. In the lower-fit, FMD reduced after HIIE [reduction of 0.85 % (95% CI, 0.12 to 1.58), P=0.02), and remained decreased at 60 min (P=0.05). In the higher-fit FMD was unchanged immediately after HIIE and increased after 60 min [increase of 1.52 % (95% CI, 0.41 to 2.62), P<0.01], which was correlated with VO2peak (r =0.41; P<0.01). Exercise-intensity alters the FMD response in elderly adults, and VO2peak modulates the FMD response following HIIE, but not MICE. The sustained decrease in FMD in the lower-fit may represent a signal for vascular adaptation or endothelial fatigue

Measuring Accuracy of Automated Parsing and Categorization Tools and Processes in Digital Investigations

This work presents a method for the measurement of the accuracy of evidential artifact extraction and categorization tasks in digital forensic investigations. Instead of focusing on the measurement of accuracy and errors in the functions of digital forensic tools, this work proposes the application of information retrieval measurement techniques that allow the incorporation of errors introduced by tools and analysis processes. This method uses a `gold standard' that is the collection of evidential objects determined by a digital investigator from suspect data with an unknown ground truth. This work proposes that the accuracy of tools and investigation processes can be evaluated compared to the derived gold standard using common precision and recall values. Two example case studies are presented showing the measurement of the accuracy of automated analysis tools as compared to an in-depth analysis by an expert. It is shown that such measurement can allow investigators to determine changes in accuracy of their processes over time, and determine if such a change is caused by their tools or knowledge.Comment: 17 pages, 2 appendices, 1 figure, 5th International Conference on Digital Forensics and Cyber Crime; Digital Forensics and Cyber Crime, pp. 147-169, 201

Effective field theory in the top sector: Do multijets help?

Many studies of possible new physics employ effective field theory (EFT), whereby corrections to the Standard Model take the form of higher-dimensional operators, suppressed by a large energy scale. Fits of such a theory to data typically use parton-level observables, which limits the data sets one can use. In order to theoretically model search channels involving many additional jets, it is important to include tree-level matrix elements matched to a parton shower algorithm, and a suitable matching procedure to remove the double counting of additional radiation. There are then two potential problems: (i) EFT corrections are absent in the shower, leading to an extra source of discontinuities in the matching procedure; (ii) the uncertainty in the matching procedure may be such that no additional constraints are obtained from observables sensitive to radiation. In this paper, we review why the first of these is not a problem in practice and perform a detailed study of the second. In particular, we quantify the additional constraints on EFT expected from top pair plus multijet events, relative to inclusive top pair production alone

Accurate Parameter Extraction From Liquids Measured Using On-chip Terahertz Spectroscopy

We introduce a method for estimating the permittivity of liquid samples measured using integrated microfluidic/planar Goubau line terahertz waveguides, in which simulation results are incorporated with measurement data to enable accurate frequency-dependent analysis

The Real Combination Problem : Panpsychism, Micro-Subjects, and Emergence

Panpsychism harbors an unresolved tension, the seriousness of which has yet to be fully appreciated. I capture this tension as a dilemma, and offer panpsychists advice on how to resolve it. The dilemma, briefly, is as follows. Panpsychists are committed to the perspicuous explanation of macro-mentality in terms of micro-mentality. But panpsychists take the micro-material realm to feature not just mental properties, but also micro-subjects to whom these properties belong. Yet it is impossible to explain the constitution of a macro-subject (like one of us) in terms of the assembly of micro-subjects, for, I show, subjects cannot combine. Therefore the panpsychist explanatory project is derailed by the insistence that the world’s ultimate material constituents (ultimates) are subjects of experience. The panpsychist faces a choice of abandoning her explanatory project, or recanting the claim that the ultimates are subjects. This is the dilemma. I argue that the latter option is to be preferred. This needn’t constitute a wholesale abandonment of panpsychism, however, since panpsychists can maintain that the ultimates possess phenomenal qualities, despite not being subjects of those qualities. This proposal requires us to make sense of phenomenal qualities existing independently of experiencing subjects, a challenge I tackle in the penultimate section. The position eventually reached is a form of neutral monism, so another way to express the overall argument is to say that, keeping true to their philosophical motivations, panpsychists should really be neutral monists.Peer reviewedFinal Accepted Versio

On-chip Terahertz Spectroscopy of Liquid Mixtures

We demonstrate 'through-substrate' sensing of fluids for application in the terahertz spectroscopy of biological materials. This technique employs planar Goubau lines with integrated photoconductive material, formed on a flexible, thin polyimide substrate, and bonded to a microfluidic channel. Few-picosecond pulses are used to probe liquid samples confined within the channel, over a total interaction length of 4 mm, overcoming water-absorption limitations of free-space terahertz transmission measurements

Spatially Resolved On-Chip Picosecond Pulse Detection Using Graphene

We present an on-chip time domain terahertz (TD-THz) system in which picosecond pulses are generated in low-temperature-grown gallium arsenide (LT-GaAs) and detected in graphene. The detected pulses were found to vary in amplitude, full width at half maximum (FWHM), and DC offset when sampled optically at different locations along a 50-μm-long graphene photoconductive (PC) detector. The results demonstrate the importance of detection location and switch design in graphene-based on-chip PC detectors