Diboson Production at the Tevatron

We present the latest results on the production of WW, WZ, Wgamma, Zgamma and ZZ events at the Fermilab Tevatron Collider. The results are based on the analyses of 0.2 -- 2 /fb of data collected in p pbar collisions at sqrt(s) = 1.96 TeV by CDF and DO experiments during the Tevatron Run II. Analyses of the diboson production processes provide crucial test of the Standard Model, directly probing its predictions on the Trilinear Gauge Couplings.Comment: Invited talk at the Hadron Collider Physics Symposium (HCP2008), Galena, Illinois, USA, May 27-31, 2008; 9 pages, LaTex, 11 eps figure

MSSM SUSY Searches at LEP2

The status of SUSY searches at LEP2 up to centre-of-mass energy of 202 GeV is presented. Search strategies for sleptons, squarks, charginos and neutralinos are discussed in the framework of Minimal Supersymmetric Standard Model with R-parity conservation. With no indication for the production of these particles new limits are set on their masses.Comment: Talk presented at 35th Rencontres de Moriond: ElectroWeak Interactions and Unified Theories, Les Arcs, Savoie, France, March 11-18, 2000. LaTex, 8 pages, uses moriond.st

The analysis of immigration trends of skilled migrants: case of Georgia

In this paper we investigate several aspects of the contemporary immigration in post-Soviet Georgia by analyzing some recent trends related to the migration phenomena in the country. Our results are based on an extensive field work with two main groups - one, with skilled foreign immigrants in Georgia, and the other, with return Georgian emigrants, both covering all of the country’s territory. Finally, we discuss the return migration and the existing programs of voluntary return between Georgia and other countries, as well as the opportunities for professional realization in the country of the Georgian returnees and the foreign immigrants

THE ANALYSIS OF IMMIGRATION TRENDS OF SKILLED MIGRANTS: CASE OF GEORGIA

In this paper, we investigate several aspects of the contemporary immigration in post-Soviet Georgia by analyzing some recent trends related to the migration phenomena in the country. Our results are based on extensive fieldwork with two main groups – one, with skilled foreign immigrants in Georgia, and the other, with return Georgian emigrants, both covering all of the country’s territory. Finally, we discuss the return migration and the existing programs of voluntary return between Georgia and other countries, as well as the opportunities for professional realization in the country of the Georgian returnees and the foreign immigrants. &nbsp

Explainable AI for ML jet taggers using expert variables and layerwise relevance propagation

A framework is presented to extract and understand decision-making information from a deep neural network (DNN) classifier of jet substructure tagging techniques. The general method studied is to provide expert variables that augment inputs ("eXpert AUGmented" variables, or XAUG variables), then apply layerwise relevance propagation (LRP) to networks both with and without XAUG variables. The XAUG variables are concatenated with the intermediate layers after network-specific operations (such as convolution or recurrence), and used in the final layers of the network. The results of comparing networks with and without the addition of XAUG variables show that XAUG variables can be used to interpret classifier behavior, increase discrimination ability when combined with low-level features, and in some cases capture the behavior of the classifier completely. The LRP technique can be used to find relevant information the network is using, and when combined with the XAUG variables, can be used to rank features, allowing one to find a reduced set of features that capture part of the network performance. In the studies presented, adding XAUG variables to low-level DNNs increased the efficiency of classifiers by as much as 30-40\%. In addition to performance improvements, an approach to quantify numerical uncertainties in the training of these DNNs is presented.Comment: 38 pages, 30 figure

Measurement of the top quark mass using the matrix element technique in dilepton final states

We present a measurement of the top quark mass in pp¯ collisions at a center-of-mass energy of 1.96 TeV at the Fermilab Tevatron collider. The data were collected by the D0 experiment corresponding to an integrated luminosity of 9.7  fb−1. The matrix element technique is applied to tt¯ events in the final state containing leptons (electrons or muons) with high transverse momenta and at least two jets. The calibration of the jet energy scale determined in the lepton+jets final state of tt¯ decays is applied to jet energies. This correction provides a substantial reduction in systematic uncertainties. We obtain a top quark mass of mt=173.93±1.84  GeV