Track identification in SiW ECal

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A precise characterisation of the top quark electro-weak vertices at the ILC

Top quark production in the process $e^+e^- \to t\bar{t}$ at a future linear electron positron collider with polarised beams is a powerful tool to determine indirectly the scale of new physics. The presented study, based on a detailed simulation of the ILD detector concept, assumes a centre-of-mass energy of $\sqrt{s}=500\,$GeV and a luminosity of $\mathcal{L}=500\,{\rm fb}^{-1}$ equally shared between the incoming beam polarisations of $\mathcal{P}_{e^-}, \mathcal{P}_{e^+} =\pm0.8,\mp0.3$. Events are selected in which the top pair decays semi-leptonically and the cross sections and the forward-backward asymmetries are determined. Based on these results, the vector, axial vector and tensorial $CP$ conserving couplings are extracted separately for the photon and the $Z^0$ component. With the expected precision, a large number of models in which the top quark acts as a messenger to new physics can be distinguished with many standard deviations. This will dramatically improve expectations from e.g. the LHC for electro-weak couplings of the top quark.Comment: This work is an update of arXiv:1307.8102, minor changes w.r.t. v1 (typos, wrong grammar, incomplete sentences etc.

Forming of the functional nanostructures on dielectric surfaces by thermal evaporation in vacuum

Встановлені умови формування пошарових нанометричних покриттів SiO₂, C, TiO₂ на діелектричні поверхні з подальшим створенням на них наноструктур комбінованим методом термовакуумного випаровування. Методами растрової електронної та атомно-силової мікроскопії досліджені залишкові мікронерівності та стан поверхонь функціональних наноструктур в процесі їх експлуатації в умовах агресивних середовищ. Показано, що формування функціональних наноструктур на діелектричних поверхнях термічним випаровуванням у вакуумі дозволяє покращити мікрогеометрію цих поверхонь, зменшити залишкову поруватість покриттів та забезпечити їх гідрофобність, чим підвищити у 1,5…2 рази їх зносостійкість та на 15…22% - адгезійну міцність.Purpose. Determination of terms of forming of layer functional nanostructures is by causing on the dielectric surfaces of nanometrical coverages of SiO₂, C, TiO₂ and forming of its nanostructures by the combined method of thermal and vacuum evaporation; application of method of raster electronic and atomic-force microscopy is for research of remaining inequalities and state of surface of functional nanostructures in the process of its exploitation. Design/methodology/approach. The feature of the combined method offered in-process is realization of its in one technological loop the "thermal and vacuum besieging is cathode-ray modification of coverage" at the unchanging terms of working environment (p = 5.10⁻⁵ Pa) that eliminates formation of compounds of coverage, at co-operating with the elements of environment on the intermediate stage of forming of nanostructure. Remaining inequalities and state of surfaces of functional nanostructures are investigational the methods of raster electronic and atomic-force microscopy in the process of its exploitation in the conditions of aggressive environments. Findings. Set terms of forming of layer nanometrical coverages of SiO₂, C, TiO₂ on dielectric surfaces with further creation on its of nanostructures by the combined method of thermal and vacuum evaporation. Originality/value. It is shown that forming of functional nanostructures on dielectric surfaces in a vacuum allows thermal evaporation to improve microgeometry of its surfaces, decrease remaining porosity coverages and to provide its hydrophobic, what to promote in 1,5…2 times its wearproofness and on 15…22% - adhesion strength.Установлены условия формирования послойных нанометрических покрытий SiO₂, C, TiO₂ на диэлектрических поверхностях с дальнейшим созданием на них наноструктур комбинированным методом термовакуумного испарения. Методами растровой электронной и атомно-силовой микроскопии исследованы остаточные микронеровности и состояние поверхностей функциональных наноструктур в процессе их эксплуатации в условиях агрессивных сред. Показано, что формирование функциональных наноструктур на диэлектрических поверхностях термическим испарением в вакууме позволяет улучшить микрогеометрию этих поверхностей, уменьшить остаточную пористость покрытий и обеспечить их гидрофобность, чем повысить в 1,5…2 раза их износостойкость и на 15…22% - адгезионную прочность

1-(8-Bromo-2-methyl-4-thioxo-3,4,5,6-tetra­hydro-2H-2,6-methano-1,3-benzoxazocin-11-yl)ethanone

In the title compound, C14H14BrNO2S, there are two similar non-equivalent mol­ecules in the asymmetric unit, displaying three chiral centres each. In the crystal structure, they are linked by inter­molecular N—H⋯O hydrogen bonds to form infinite chains, which are in turn connected by weak Br⋯H and S⋯H inter­actions

Search for Axionlike Particles Produced in e+e- Collisions at Belle II

© 2020 authors. Published by the American Physical Society. Published by the American Physical Society under the terms of the https://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article\u27s title, journal citation, and DOI. Funded by SCOAP3. We present a search for the direct production of a light pseudoscalar a decaying into two photons with the Belle II detector at the SuperKEKB collider. We search for the process e+e-→γa, a→γγ in the mass range 0.

Hadron shower decomposition in the highly granular CALICE analogue hadron calorimeter

The spatial development of hadronic showers in the CALICE scintillator-steel analogue hadron calorimeter is studied using test beam data collected at CERN and FNAL for single positive pions and protons with initial momenta in the range from 10 to 80 GeV/c. Both longitudinal and radial development of hadron showers are parametrised with two-component functions. The parametrisation is fit to test beam data and simulations using the QGSP_BERT and FTFP_BERT physics lists from Geant4 version 9.6. The parameters extracted from data and simulated samples are compared for the two types of hadrons. The response to pions and the ratio of the non-electromagnetic to the electromagnetic calorimeter response, h/e, are estimated using the extrapolation and decomposition of the longitudinal profiles.Comment: 38 pages, 19 figures, 5 tables; author list changed; submitted to JINS

B-flavor tagging at Belle II

We report on new flavor tagging algorithms developed to determine the quark-flavor content of bottom ( ) mesons at Belle II. The algorithms provide essential inputs for measurements of quark-flavor mixing and charge-parity violation. We validate and evaluate the performance of the algorithms using hadronic decays with flavor-specific final states reconstructed in a data set corresponding to an integrated luminosity of 62.8 fb−1 , collected at the resonance with the Belle II detector at the SuperKEKB collider. We measure the total effective tagging efficiency to be εeff=(30.0±1.2(stat)±0.4(syst))% for a category-based algorithm and εeff=(28.8±1.2(stat)±0.4(syst))% for a deep-learning-based algorithm