Bose-Einstein correlations in WW events at LEP

The current status of the LEP results on Bose-Einstein correlations is discussed. Emphasis is given to the measurement of Bose-Einstein correlations between decay products from different W's, in an energy range between 172 and 209 GeV, dependent on the experiment. For the first time all four LEP experiments conclude that no evidence for correlations between pions from different W's is seen at the current level of precision.Comment: 6 pages, 4 figures, Talk given at XXXVI Rencontres de Moriond, Les Arcs, France, March 17-24 200

Bose-Einstein correlations in WW pair production at LEP

This paper presents an overview of the latest results from the L3 and DELPHI collaborations concerning the measurement of Bose-Einstein correlations between identical bosons coming from different W's in fully hadronic WW decays. Using the same method, L3 sees no indication of any inter-W BEC effect, while DELPHI reports an indication of inter-W BEC between like-charged particles of the order of three standard deviations.Comment: 5 pages, 4 figures, Talk given at the XXXVIIIth Rencontres de Moriond (QCD), Les Arcs, France, March 22-29 200

Investigation of Bose-Einstein Correlations in 3 jet events with the DELPHI detector

A preliminary investigation of Bose-Einstein correlations in 3 jet events has been made by analysing the collected data at the $Z^0$ peak from '94 and '95 and the calibration runs during the LEP2 period from '97 to 2000. Three methods were used to extract two-particle correlation functions. No significant difference was found between quark and gluon jets for all three methods.Comment: 6 pages, 2 figures in ps and 1 in eps, talk given at XXXI International Symposium on Multiparticle Dynamics, Sept 1-7, 2001, Datong China. see http://ismd31.ccnu.edu.cn

Minimum bias and underlying event studies at CMS

The Underlying Event (UE) at CMS is studied by examining charged particle and momentum densities in the transverse region in charged particle jet production. The predictions of various QCD models with different multiple parton interaction schemes correctly reproduce Tevatron data, however they fail to agree with each other when extrapolated to the LHC energy. The possibility of discriminating among these models is presented. Exploring QCD dynamics in proton-proton collisions at center-of-mass energy of 14 TeV, and the importance of improving and tuning the QCD Monte Carlo models at start-up are also analyzed

Particle production in pp collisions at the LHC as studied by CMS

This is a report on the study of hadron production in non-singlediffractive events by using minimum bias and jet triggered data collected with the CMS experiment in the first year of LHC running. The importance of these measurements lies in the understanding of the dynamics of multi-hadron production which is described by non-perturbative QCD. The modeling via Monte Carlo generators, and their respective re-tuning, is necessary to describe the underlying event and pileup, having impact on many measurements that rely on an accurate measurement of hadron jets or missing transverse energy. I present an overview of the inclusive single particle spectra, the yields of strange hadrons and the charged hadron multiplicity distributions measured at several center-of-mass energies that show a fast growth of particle densities at the highest energies, especially for low transverse momenta, and a strong violation of KNO scaling in large pseudorapidity intervals

Stochastic gravitational wave background: methods and Implications

Beyond individually resolvable gravitational wave events such as binary black hole and binary neutron star mergers, the superposition of many more weak signals coming from a multitude of sources is expected to contribute to an overall background, the so-called stochastic gravitational wave background. In this review, we give an overview of possible detection methods in the search for this background and provide a detailed review of the data-analysis techniques, focusing primarily on current Earth-based interferometric gravitational-wave detectors. In addition, various validation techniques aimed at reinforcing the claim of a detection of such a background are discussed as well. We conclude this review by listing some of the astrophysical and cosmological implications resulting from current upper limits on the stochastic background of gravitational waves.Comment: 71 pages, 17 figures, review articl

The metallicity dependence and evolutionary times of merging binary black holes: Combined constraints from individual gravitational-wave detections and the stochastic background

The advent of gravitational-wave astronomy is now allowing for the study of compact binary merger demographics throughout the Universe. This information can be leveraged as tools for understanding massive stars, their environments, and their evolution. One active question is the nature of compact binary formation: the environmental and chemical conditions required for black hole birth and the time delays experienced by binaries before they merge. Gravitational-wave events detected today, however, primarily occur at low or moderate redshifts due to current interferometer sensitivity, therefore limiting our ability to probe the high redshift behavior of these quantities. In this work, we circumvent this limitation by using an additional source of information: observational limits on the gravitational-wave background from unresolved binaries in the distant Universe. Using current gravitational-wave data from the first three observing runs of LIGO-Virgo-KAGRA, we combine catalogs of directly detected binaries and limits on the stochastic background to constrain the time-delay distribution and metallicity dependence of binary black hole evolution. Looking to the future, we also explore how these constraints will be improved at the Advanced LIGO A+ sensitivity. We conclude that, although binary black hole formation cannot be strongly constrained with today's data, the future detection (or a non-detection) of the gravitational-wave background with Advanced LIGO A+ will carry strong implications for the evolution of binary black holes

Predicting soil erosion after land use changes for irrigating agriculture in a large reservoir of southern Portugal

The construction of the Alqueva reservoir in a semi-arid Mediterranean landscape brought new opportunities for irrigated farming. Land use changes and climate change may alter the risk of soil erosion that was not predicted in the initial development plans and decrease the lifetime of the investment. A comprehensive methodology that integrates the Revised Universal Soil Loss Equation (RUSLE) and geographic information system was adopted to study the effect on soil erosion of different land-uses of the Alqueva reservoir region. Analysing the soil erosion of each land-use it was obtained the following land use erosion vulnerability: Olive orchard>Vineyard>Montado>Alfalfa. The strong erosion variances that were observed in the study area show the importance of locating the 'hot spots' of soil erosion. Simulated scenarios for the entire area can be used as a basis for site-specific soil conservation plans, to promote sustainable land management practices and to facilitate localized erosion control practices and environmentally friendly farming. (C) 2015 The Authors. Published by Elsevier B.V