JIMWLK and beyond : From concepts to observables

Volume: 112 Host publication title: 6th International Conference on Physics Opportunities at an Electron-Ion ColliderThe Color Glass Condensate and its associated evolution equation, the JIMWLK equation have applications to many observables far beyond totally inclusive observables. The phenomenology is so rich that little has been done to explore beyond scaling behavior of correlators. We show first examples that exemplify the considerations necessary to access additional information both experimentally and theoretically and demonstrate that the Wilson line correlators appearing throughout make it imperative to consistently take into account that one is dealing with correlators of group elements and demonstrate how this imposes physical and phenomenological constraints. Similar considerations apply also to jet observables at finite N-c.Peer reviewe

Gaze doesn’t always lead steering

In car driving, gaze typically leads the steering when negotiating curves. The aim of the current study was to investigate whether drivers also use this gaze-leads-steering strategy when time-sharing between driving and a visual secondary task. Fourteen participants drove an instrumented car along a motorway while performing a secondary task: looking at a specified visual target as long and as much as they felt it was safe to do so. They made six trips, and in each trip the target was at a different location relative to the road ahead. They were free to glance back at the road at any time. Gaze behaviour was measured with an eye tracker, and steering corrections were recorded from the vehicle’s CAN bus. Both in-car ‘Fixation’ targets and outside ‘Pursuit’ targets were used. Drivers often used a gaze-leads-steering strategy, glancing at the road ahead 200–600 ms before executing steering corrections. However, when the targets were less eccentric (requiring a smaller change in glance direction relative to the road ahead), the reverse strategy, in which glances to the road ahead followed steering corrections with 0–400 ms latency, was clearly present. The observed use of strategies can be interpreted in terms of predictive processing: The gaze-leads-steering strategy is driven by the need to update the visual information and is therefore modulated by the quality/quantity of peripheral information. Implications for steering models are discussed.Peer reviewe

Trade-off between jerk and time headway as an indicator of driving style

Variation in longitudinal control in driving has been discussed in both traffic psychology and transportation engineering. Traffic psychologists have concerned themselves with “driving style”, a habitual form of behavior marked by it’s stability, and its basis in psychological traits. Those working in traffic microsimulation have searched for quantitative ways to represent different driver-car systems in car following models. There has been unfortunately little overlap or theoretical consistency between these literatures. Here, we investigated relationships between directly observable measures (time headway, acceleration and jerk) in a simulated driving task where the driving context, vehicle and environment were controlled. We found individual differences in the way a trade-off was made between close but jerky vs. far and smooth following behavior. We call these “intensive” and “calm” driving, and suggest this trade-off can serve as an indicator of a possible latent factor underlying driving style. We posit that pursuing such latent factors for driving style may have implications for modelling driver heterogeneity across various domains in traffic simulation.Peer reviewe

HERA-data in the light of small x evolution with state of the art NLO input

Both total and diffractive cross sections from HERA are successfully confronted with JIMWLK evolution equations in the asymptotic pseudo-scaling region. We present a consistent, simultaneous description of both types of cross sections that includes NLO corrections in the form of running coupling and energy conservation corrections. The inclusion of energy conservation corrections allows to match all available data with x below .02 i.e. up to Q^2 of 1200 GeV^2. We discuss the effects of quark masses including charm, contrast asymptotic and pre-asymptotic fit strategies, and survey non-perturbative uncertainties related to impact parameter dependence.Comment: 61 pages, 27 figure

Predictions for cold nuclear matter effects in p plus Pb collisions at root SNN =8.16 TeV

Predictions for cold nuclear matter effects on charged hadrons, identified light hadrons, quarkonium and heavy flavor hadrons, Drell-Yan dileptons, jets, photons, gauge bosons and top quark pairs produced in p+Pb collisions at, root S-NN = 8.16 TeV are compiled and, where possible, compared to each other. Predictions of the normalized ratios of p+Pb to p+ p cross sections are also presented for most of the observables, providing new insights into the expected role of cold nuclear matter effects. In particular, the role of nuclear parson distribution functions on particle production can now be probed over a wider range of phase space than ever before. (C) 2018 Elsevier B.V. All rights reserved.Peer reviewe

VALTAVAn seurantatutkimus : Osa 1. Lähtökohdat ja tavoitteet

Hannu Lappi: Korporatiivinen etujen välittyminen ja konsensuksen muodostaminen: sosiaali- ja terveydenhuollon valtionosuuksien tasaaminen eli ns. VALTAVA-uudistus. Kari Gröhn: Säädösvalmisteluohjeiden noudattaminen ja soveltaminen VALTAVA-uudistuksen laadinnassa.Julkaisu saatavilla Tilastokirjastossa:https://tilastokeskus.finna.fi/Record/tilda.39286Suomen virallinen tilasto (SVT

JIMWLK and beyond: From concepts to observables

The Color Glass Condensate and its associated evolution equation, the JIMWLK equation have applications to many observables far beyond totally inclusive observables. The phenomenology is so rich that little has been done to explore beyond scaling behavior of correlators. We show first examples that exemplify the considerations necessary to access additional information both experimentally and theoretically and demonstrate that the Wilson line correlators appearing throughout make it imperative to consistently take into account that one is dealing with correlators of group elements and demonstrate how this imposes physical and phenomenological constraints. Similar considerations apply also to jet observables at finite Nc

A computational model for driver's cognitive state, visual perception and intermittent attention in a distracted car following task

We present a computational model of intermittent visual sampling and locomotor control in a simple yet representative task of a car driver following another vehicle. The model has a number of features that take it beyond the current state of the art in modelling natural tasks, and driving in particular. First, unlike most control theoretical models in vision science and engineering—where control is directly based on observable (optical) variables—actions are based on a temporally enduring internal representation. Second, unlike the more sophisticated engineering driver models based on internal representations, our model explicitly aims to be psychologically plausible, in particular in modelling perceptual processes and their limitations. Third, unlike most psychological models, it is implemented as an actual simulation model capable of full task performance (visual sampling and longitudinal control). The model is developed and validated using a dataset from a simplified car-following experiment (N = 40, in both three-dimensional virtual reality and a real instrumented vehicle). The results replicate our previously reported connection between time headway and visual attention. The model reproduces this connection and predicts that it emerges from control of action uncertainty. Implications for traffic psychological models and future developments for psychologically plausible yet computationally rigorous models of full natural task performance are discussed.Peer reviewe