1,071 research outputs found
Prospects for the Search for a Doubly-Charged Higgs in the Left-Right Symmetric Model with ATLAS
We estimate the potential for observation at the LHC of a doubly charged
Higgs boson, as predicted in Left-Right symmetric models. Single production by
vector boson fusion, and pair production by the
Drell-Yan process are
considered. Various decay channels are investigated: dileptons, including pairs
of 's, as well as $WW
Electron/Photon Reconstruction Performance with the ATLAS Detector
The calibration of electromagnetic clusters is one of the key issues of ATLAS (and the LHC) in 2007. The cluster algorithm starting from electronically calibrated calorimeter cells will be described. Local position and local energy variations are corrected for. As a last step, longitudinal weights are applied to correct for energy loss upstream of the calorimeter. Strongly influenced by testbeam studies, the new longitudinal weighting optimizes simultaneously energy resolution and linearity. Methods to derive the final calibration parameters from the physics events have been developed. The electron and photon identification methods and their performance will then be discussed
Electrons/Photons Reconstruction with the ATLAS Detector
The calibration of electromagnetic clusters is one of the key issues of ATLAS (and the LHC) in 2007. The cluster alogrithm starting from electronically calibrated calorimeter cells will be described. Local position and local energy variations are corrected for. As a last step, longitudinal weights are applied to correct for energy loss upstream of the calorimeter. Strongly influenced by testbeam studies, the new longitudinal weighting optimizes simultaneously energy resolution and linearity. Methods to derive the final calibration parameters from the physics events have been developped. The electron and photon identification methods (cuts and multivariate analyses) and their performance will then be discussed
Other BSM Searches at the LHC
The considerable center-of-mass energy and luminosity provided by the Large Hadron Collider (LHC) will ensure a discovery reach for new particles which extends well into the multi-TeV region. ATLAS and CMS have carried out many studies of the implications of this capability for Beyond the Standard Model physics. In this paper, we summarize the results of studies involving, leptons and jets with and without missing transverse energy in the final state. We will mainly focus on the potential for discovery and limits setting with an integrated luminosity of the order of 100 to 200 pb-1 per experiment
Efficiency of Hydrogen Peroxide and Fenton Reagent for Polycyclic Aromatic Hydrocarbon Degradation in Contaminated Soil: Insights from Experimental and Predictive Modeling
\ua9 2024 by the authors.This study investigates the degradation kinetics of polycyclic aromatic hydrocarbons (PAHs) in contaminated soil using hydrogen peroxide (H2O2) and the Fenton process (H2O2/Fe2+). The effect of oxidant concentration and the Fenton molar ratio on PAH decomposition efficiency is examined. Results reveal that increasing H2O2 concentration above 25 mmol/samples leads to a slight increase in the rate constants for both first- and second-order reactions. The Fenton process demonstrates higher efficiency in PAH degradation compared to H2O2 alone, achieving decomposition yields ranging from 84.7% to 99.9%. pH evolution during the oxidation process influences PAH degradation, with alkaline conditions favoring lower elimination rates. Fourier-transform infrared (FTIR) spectroscopy analysis indicates significant elimination of PAHs after treatment, with both oxidants showing comparable efficacy in complete hydrocarbon degradation. The mechanisms of PAH degradation by H2O2 and the Fenton process involve hydroxyl radical formation, with the latter exhibiting greater efficiency due to Fe2+ catalysis. Gaussian process regression (GPR) modeling accurately predicts reduced concentration, with optimized ARD-Exponential kernel function demonstrating superior performance. The Improved Grey Wolf Optimizer algorithm facilitates optimization of reaction conditions, yielding a high degree of agreement between experimental and predicted values. A MATLAB 2022b interface is developed for efficient optimization and prediction of C/C0, a critical parameter in PAH degradation studies. This integrated approach offers insights into optimizing the efficiency of oxidant-based PAH remediation techniques, with potential applications in contaminated soil remediation
Ultrasound-assisted extraction, LC–MS/MS analysis, anticholinesterase, and antioxidant activities of valuable natural netabolites from Astragalus armatus Willd.: In silico molecular docking and In Vitro enzymatic studies
The Astragalus armatus Willd. plant’s phenolic constituent extraction and identification were optimized using the ultrasound-assisted extraction (UAE) method and the LC–MS/MS analysis, respectively. Additionally, cupric reducing antioxidant capacity (CUPRAC), beta carotene, reducing power, DMSO alcalin, silver nanoparticle (SNP)-based method, phenanthroline, and hydroxyl radical tests were utilized to assess the extract’s antioxidant capacity, while the neuroprotective effect was examined in vitro against acetylcholinesterase enzyme. This study accurately estimated the chemical bonding between the identified phenolic molecules derived from LC–MS/MS and the AChE. The extract was found to contain sixteen phenolic substances, and rosmarinic, protocatechuic, and chlorogenic acids, as well as 4-hydroxybenzoic, hyperoside, and hesperidin, were the most abundant substances in the extract. In all antioxidant experiments, the plant extract demonstrated strong antioxidant activity and a significant inhibitory impact against AChE (40.25 ± 1.41 μg/mL). According to molecular docking affinity to the enzyme AChE, the top-five molecules were found to be luteolin, quercetin, naringenin, rosmarinic acid, and kaempferol. Furthermore, these tested polyphenols satisfy the essential requirements for drug-like characteristics and Lipinski’s rule of five. These results highlight the significance of the A. armatus plant in cosmetics, as food additives, and in the pharmaceutical industry due to its rosmarinic and chlorogenic acid content
New Lower Bound on Fermion Binding Energies
We derive a new lower bound for the ground state energy of N
fermions with total spin S in terms of binding energies of (N-1) fermions. Numerical examples are provided for some simple
short-range or confining potentials.Comment: 4 pages, 1 eps figur
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