Search results for "event"

Energy dependence of the differences between the quark and gluon jet fragmentation

1996

Three jet events arising from decays of the Z beson, collected by the DELPHI detector, were used to measure differences in quark and gluon fragmentation. Gluon jets were anti-tagged by identifying b quark jets. Unbiased quark jets came from events with two jets plus one photon. Quark and gluon jet properties in different energy ranges were compared for the first time within the same detector. Quark and gluon jets of nearly the same energy in symmetric three jet event topologies were also compared. Using three independent methods, the average value of the ratio of the mean charged multiplicities of gluon and quark jets is [ r ] = 1.241 +/- 0.015 (stat.) +/- 0.025 (syst.). Gluon jets are broa…

The Scale Dependence of the Hadron Multiplicity in Quark and Gluon Jets and a Precise Determination of $C_{A}/C_{F}$

1999

\frac{C_A}{C_F} = 2.246 \pm 0.062~(stat.) \pm 0.080~(syst.) \pm 0.095~(theo.) Data collected at the Z resonance using the DELPHI detector at LEP are used to determine the charged hadron multiplicity in gluon and quark jets as a function of a transverse momentum-like scale. The colour factor ratio, \cacf, is directly observed in the increase of multiplicities with that scale. The smaller than expected multiplicity ratio in gluon to quark jets is understood by differences in the hadronization of the leading quark or gluon. From the dependence of the charged hadron multiplicity on the opening angle in symmetric three-jet events the colour factor ratio is measured to be: C_A/C_F = 2.246 \pm 0.0…

A measurement of Rb using mutually exclusive tags

1997

A measurement of R-b using five mutually exclusive hemisphere tags has been performed by ALEPH using the full LEP1 statistics. Three tags are designed to select the decay of the Z(0) to b quarks, while the remaining two select Z(0) decays to c and light quarks, and are used to measure the tagging efficiencies. The result, R-b = 0.2159 +/- 0.0009(stat) +/-0.0011(syst), is in agreement with the electroweak theory prediction of 0.2158 +/- 0.0003. (C) 1997 Published by Elsevier Science B.V. RI ANTONELLI, ANTONELLA/C-6238-2011; Passalacqua, Luca/F-5127-2011; Murtas, Fabrizio/B-5729-2012; St.Denis, Richard/C-8997-2012; Forti, Francesco/H-3035-2011; Ferrante, Isidoro/F-1017-2012

Subjet multiplicity of gluon and quark jets reconstructed with thek⊥algorithm inpp¯collisions

2002

The D empty set Collaboration has studied for the first time the properties of hadron-collider jets reconstructed with a successive-combination algorithm based on relative transverse momenta (k(perpendicular to)) of energy clusters. Using the standard value D = 1.0 of the jet-separation parameter in the k(perpendicular to) algorithm, we find that the p(T) of such jets is higher than the E-T of matched jets reconstructed with cones of radius R = 0.7, by about 5 (8) GeV at p(T) approximate to90 (240) GeV. To examine internal jet structure, the k(perpendicular to) algorithm is applied within D = 0.5 jets to resolve any subjets. The multiplicity of subjets in jet samples at roots = 1800 GeV and…

Vertebrate biological events and Pleistocene biogeographic history of Sicily

2009

Extractingqˆin event-by-event hydrodynamics and the centrality/energy puzzle

2017

Abstract In our analysis, we combine event-by-event hydrodynamics, within the EKRT formulation, with jet quenching -ASW Quenching Weights- to obtain high- p T R AA for charged particles at RHIC and LHC energies for different centralities. By defining a K -factor that quantifies the departure of q ˆ from an ideal estimate, K = q ˆ / ( 2 ϵ 3 / 4 ) , we fit the single-inclusive experimental data for charged particles. This K -factor is larger at RHIC than at the LHC but, surprisingly, it is almost independent of the centrality of the collision.

Low physical activity and its association with diabetes and other cardiovascular risk factors: a nationwide, population-based study

2016

Spanish Biomedical Research Centre in Diabetes and Associated Metabolic Disorders (CIBERDEM; ISCIII Ministerio de Ciencia e Innovacion); Ministerio de Sanidad y Consumo; Spanish Diabetes Society (SED)

Exercise, Sports & Cardiovascular Health: Relevant Questions and Answers

2019

Introduction Currently, it is quite common for a clinical cardiologist to be questioned about exercise and sports, topics that are rarely discussed during formal medical education. In this regard, there is a clear need to access high-quality data and evidence-based information to give patients and family members the best advice. Aiming to present the state-of-the art scientific information on the topic, we have invited several experts from different countries, all of them “knowledge-producers” in exercise and sports cardiology, to contribute [...]

Root Cause Analysis relativa ad un evento sentinella da errore della somministrazione di terapia farmacologica in un'U.O: dell'A.O.U.P:

2012

Cancer prevention with aspirin in hereditary colorectal cancer (Lynch syndrome), 10-year follow-up and registry-based 20-year data in the CAPP2 study…

2020

BACKGROUND: Lynch syndrome is associated with an increased risk of colorectal cancer and with a broader spectrum of cancers, especially endometrial cancer. In 2011, our group reported long-term cancer outcomes (mean follow-up 55·7 months [SD 31·4]) for participants with Lynch syndrome enrolled into a randomised trial of daily aspirin versus placebo. This report completes the planned 10-year follow-up to allow a longer-term assessment of the effect of taking regular aspirin in this high-risk population.METHODS: In the double-blind, randomised CAPP2 trial, 861 patients from 43 international centres worldwide (707 [82%] from Europe, 112 [13%] from Australasia, 38 [4%] from Africa, and four [&l…