Dominant QCD Backgrounds in Higgs Boson Analyses at the LHC: A Study of pp -> t anti-t + 2 jets at Next-To-Leading Order

We report the results of a next-to-leading order simulation of top quark pair production in association with two jets. With our inclusive cuts, we show that the corrections with respect to leading order are negative and small, reaching 11%. The error obtained by scale variation is of the same order. Additionally, we reproduce the result of a previous study of top quark pair production in association with a single jet.Comment: 4 pages, 5 figures, 1 tabl

Non-Gaussian Geostatistical Modeling using (skew) t Processes

We propose a new model for regression and dependence analysis when addressing spatial data with possibly heavy tails and an asymmetric marginal distribution. We first propose a stationary process with $t$ marginals obtained through scale mixing of a Gaussian process with an inverse square root process with Gamma marginals. We then generalize this construction by considering a skew-Gaussian process, thus obtaining a process with skew-t marginal distributions. For the proposed (skew) $t$ process we study the second-order and geometrical properties and in the $t$ case, we provide analytic expressions for the bivariate distribution. In an extensive simulation study, we investigate the use of the weighted pairwise likelihood as a method of estimation for the $t$ process. Moreover we compare the performance of the optimal linear predictor of the $t$ process versus the optimal Gaussian predictor. Finally, the effectiveness of our methodology is illustrated by analyzing a georeferenced dataset on maximum temperatures in Australi

Assault on the NLO Wishlist: pp -> tt bb

We present the results of a next-to-leading order calculation of QCD corrections to the production of an on-shell top-anti-top quark pair in association with two flavored b-jets. Besides studying the total cross section and its scale dependence, we give several differential distributions. Where comparable, our results agree with a previous analysis. While the process under scrutiny is of major relevance for Higgs boson searches at the LHC, we use it to demonstrate the ability of our system built around Helac-Phegas to tackle complete calculations at the frontier of current studies for the LHC. On the technical side, we show how the virtual corrections are efficiently computed with Helac-1Loop, based on the OPP method and the reduction code CutTools, using reweighting and Monte Carlo over color configurations and polarizations. As far as the real corrections are concerned, we use the recently published Helac-Dipoles package. In connection with improvements of the latter, we give the last missing integrated dipole formulae necessary for a complete implementation of phase space restriction dependence in the massive dipole subtraction formalism.Comment: 19 pages, 11 figures, 2 tables. References added, version to appear in JHE

Multi-stage Strategic Approach in Spatial Innovation: How Innovation District Matter?

In the 21st century globalised economy, innovation is a crucial factor within strategies targeted at growing and sustaining competitiveness of regions and cities. Accordingly, the creation of knowledge process, along with sharing and commercialisation, became an effective response to the pressures generated by globalisation in order to increase the competitive advantage. The emerging trend of innovation-led urban planning initiatives provides strong evidence of how cities are implementing strategies to promote innovation mainstreaming. Hence, these innovation-oriented policies, which are targeted at reshaping cities, are currently translated in the creation of innovation districts. This paper aims at identifying the actors who foster the innovation process at urban level, and analysing their influence throughout the innovation district life cycle. Firstly, the authors assess the role played by public and private sector in the different stages of innovation district development, by adapting the Urban Land Institute conceptual framework in the Innovation Life Cycle District Assessment. Secondly, empirical research works are defined in order to test the ILCDA. The Boston Innovation District and the IDEA District are the two case studies under investigation, by pointing out the policies and planning initiatives undertaken in the Seaport area of Boston and in Downtown San Diego, respectively. Findings from this research highlight the level of public private partnership effectiveness in supporting the development of innovation districts. Useful lessons can be drawn in encouraging planners and policy-makers towards undertaking combined actions at the different stages of the development process

Use of Fluorescence Spectroscopy to Elucidate RNA Folding Pathways

This overview unit discusses fluorescence spectroscopy as a tool for studying RNA folding. Ribozymes and oligonucleotides can be labeled with a fluorescent probe and analyzed to give information about both slow and fast kinetic processes with real‐time data acquisition. The unit discusses the advantages and disadvantages of various pendant probes and nucleotide analogs, the analytical methods that can be used, instrument setup, control experiments, and a variety of kinetic experiments that can be performed, such as determination of rate constants.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/143791/1/cpnc1108.pd

Unifying compactly supported and Matern covariance functions in spatial statistics

The Matern family of covariance functions has played a central role in spatial statistics for decades, being a flexible parametric class with one parameter determining the smoothness of the paths of the underlying spatial field. This paper proposes a family of spatial covariance functions, which stems from a reparameterization of the generalized Wendland family. As for the Matern case, the proposed family allows for a continuous parameterization of the smoothness of the underlying Gaussian random field, being additionally compactly supported.More importantly, we show that the proposed covariance family generalizes the Matern model which is attained as a special limit case. This implies that the (reparametrized) Generalized Wendland model is more flexible than the Matern model with an extra-parameter that allows for switching from compactly to globally supported covariance functions.Our numerical experiments elucidate the speed of convergence of the proposed model to the Matern model. We also inspect the asymptotic distribution of the maximum likelihood method when estimating the parameters of the proposed covariance models under both increasing and fixed domain asymptotics. The effectiveness of our proposal is illustrated by analyzing a georeferenced dataset of mean temperatures over a region of French, and performing a re-analysis of a large spatial point referenced dataset of yearly total precipitation anomalies. (C) 2022 Published by Elsevier Inc

Helac-nlo

Based on the OPP technique and the HELAC framework, HELAC-1LOOP is a program that is capable of numerically evaluating QCD virtual corrections to scattering amplitudes. A detailed presentation of the algorithm is given, along with instructions to run the code and benchmark results. The program is part of the HELAC-NLO framework that allows for a complete evaluation of QCD NLO corrections.Comment: minor text revisions, version to appear in Comput.Phys.Commu

Mapping Connections between Neighborhoods in Response to Community-Based Social Needs

Geographic proximity might not be the only factor influencing the connections between neighborhoods within the same city. Most likely, the community's needs and behaviors play a role in facilitating or hindering any connections between these urban areas. Accordingly, relationships between communities may differ or be similar based on their respective characteristics. This paper aims to demonstrate that communities are close based on the needs they share, regardless of their ethnicity or geographic location. In this study, a time series analysis of neighborhoods' needs is explored to gain a deeper understanding of the communities' network. The study takes into account the co-occurrence of complaints/reports from residents regarding the same issue. The dataset was retrieved from the Boston Area Research Initiative (BARI) and the 311 system that describe the features of neighborhoods regarding non-emergency issues. Subsequently, the connection between neighborhoods in the City of Boston was analyzed using a mixture of PCA, K-means, association rule mining, and a network creation tool. Moreover, clustering coefficients and degrees of centrality were used as significant factors in identifying the members of groups and marking crucial nodes in the network. A series of graphs were generated to show how the neighborhoods are linked based on their socioeconomic concerns. The results prove that even geographically disconnected neighborhoods within Boston have similar social needs, despite their distance from one another. Furthermore, it revealed that some neighborhoods can act as linking bridges for other neighborhoods, while others may be isolated within the network graph. This study has increased awareness of urban aspects. The authorities may consider other dimensions than the traditional ones regarding neighborhood development and addressing problems. Finally, it helps to identify common characteristics between neighborhoods, which facilitates the policy making process