Search results for "Branching"

Three-prong τ decays with charged kaons

1998

Final states with charged kaons in three-prong τ decays are studied by exploiting the particle identification from the dE/dx measurement. The results are based on a sample of about 1.6 × 105 detected τ pairs collected with the ALEPH detector between 1991 and 1995 around the Z peak. The following branching ratios have been measured: B(τ- → K−K+π−ντ) = (1.63 ± 0.21 ± 0.17) × 10−3, B(τ− → K−π+π−ντ) = (2.14 ± 0.37 ± 0.29) × 10−3, B(τ− → K−K+π−π0ντ) = (0.75 ± 0.29 ± 0.15) × 10−3, and B(τ− → K−π+π−π0ντ) = (0.61 ± 0.39 ± 0.18) × 10−3. The first two measurements are more precise than the current world averages, while the last two channels are investigated for the first time. The 95% C.L. upper limi…

New features in systematics of low-spin states in even106?120Cd

1990

Low- spin states in even106–112Cd and116Cd were investigated by in-beam and off-beam γ-ray and conversion electron spectroscopy. New spin assignments and decay branching ratios for the levels in106Cd,108Cd and110Cd were obtained. From the new systematical data for the even106–120Cd, it is inferred that two sets of low-lying 0+ states cross between114Cd and116Cd. One of these sets appears to have features of both intruder and two-quadrupole-phonon states.

Search for Higgs Boson Decays into a Z Boson and a Light Hadronically Decaying Resonance Using 13 TeV pp Collision Data from the ATLAS Detector

2020

A search for Higgs boson decays into a Z boson and a light resonance in two-lepton plus jet events is performed, using a pp collision dataset with an integrated luminosity of 139  fb^{-1} collected at sqrt[s]=13  TeV by the ATLAS experiment at the CERN LHC. The resonance considered is a light boson with a mass below 4 GeV from a possible extended scalar sector or a charmonium state. Multivariate discriminants are used for the event selection and for evaluating the mass of the light resonance. No excess of events above the expected background is found. Observed (expected) 95% confidence-level upper limits are set on the Higgs boson production cross section times branching fraction to a Z bos…

Strong γ-ray emission from neutron unbound states populated in β-decay: Impact on (n,γ) cross-section estimates

2017

J. L. Taín et al. -- 6 pags., 7 figs., 1 tab. -- Open Access funded by Creative Commons Atribution Licence 4.0

Search for third generation scalar leptoquarks in pp collisions at √s = 7 TeV with the ATLAS detector

2013

A search for pair-produced third generation scalar leptoquarks is presented, using proton-proton collisions at √s = 7 TeV at the LHC. The data were recorded with the ATLAS detector and correspond to an integrated luminosity of 4.7 fb[superscript −1]. Each leptoquark is assumed to decay to a tau lepton and a b-quark with a branching fraction equal to 100%. No statistically significant excess above the Standard Model expectation is observed. Third generation leptoquarks are therefore excluded at 95% confidence level for masses less than 534 GeV.

Systematic Variation of the Degree of Branching (DB) of Polyglycerol via Oxyanionic Copolymerization of Glycidol with a Protected Glycidyl Ether and …

2017

Inimer-Promoted Synthesis of Branched and Hyperbranched Polylactide Copolymers

2009

A series of (hyper)branched poly(l-lactide)(PLLA) copolymers has been prepared by ring-opening multibranching copolymerization of l-lactide with a hydroxyl-functional (ABB′) lactone inimer, 5HDON (5-hydroxymethyl-1,4-dioxane-2-on). Polymerization was conducted in bulk and solution and catalyzed either by stanneous-2-ethyl hexanoate (Sn(Oct)2) or an organic base, 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD). Precise structural characterization of the resulting branched copolyester structures was accomplished by a combination of 2D NMR techniques, relying on the comparison with model compounds. The 5HDON inimer was employed in 1% to 20% fractions and is incorporated either as a dendritic unit or…

Branched versus linear oligo(dimethylsiloxane): Differences in their thermodynamic interaction with solvents

2010

The thermodynamic behavior of linear and of branched oligo(dimethylsiloxane) (O-DMS) solutions was studied by means of vapor pressure measurements and vapor pressure osmometry at different temperatures for the thermodynamically favorable solvent THF. The branched material required for that purpose was synthesized and afterwards fractionated by means of the single solvent acetone to eliminate components of low degrees of branching. The Flory-Huggins interaction parameters, χ, for the systems THF/O-DMS as a function of composition pass a minimum at all temperatures (25, 40, and 60 °C) in the case of the branched material. For the unbranched oligomer such a minimum is only observed at 60 °C. A…

Inverse response of polypropylene to gamma radiation under vacuum

1997

Abstract The effect of gamma radiation under vacuum on polypropylene is analysed on the basis of a simple kinetic model. The influence of the irradiation parameters, total absorbed dose and dose rate, on the rates of the main reactions occurring during irradiation, i.e. β-scission, addition to double bonds and termination, is studied. Using kinetic equations, and free radical and double bond balance relationships, we show that it is possible to rationalize the response of polypropylene to gamma radiation. In particular, on the basis of the mathematical solutions of these equations, we obtain the equation of an ‘inversion curve’, implicit function of the irradiation parameters, which gives t…

Measurement of upsilon production in 7 TeV pp collisions at ATLAS

2013

Artículo escrito por un elevado número de autores, solo se referencian el que aparece en primer lugar, el nombre del grupo de colaboración, si le hubiere, y los autores pertenecientes a la UAM