EVALUATION OF CHANGES OF STEREOLOGICAL PARAMETERS OF EUTECTIC PHASES IN AlSiMg ALLOY AFTER PRECIPITATION HARDENING

Qualitative microstructure investigations of the AlSiMg alloy’s microstructure in both its original state (with the characteristic primary structure) and after precipitation hardening revealed the significant heterogeneity of the eutectic phases concerning their shape, size, and distribution. An evaluation of the stereological parameters of the eutectic phases was carried out. The computer-image analysis was performed in order to define the fraction of the relative volume and shape of the eutectic phases and to establish their influence on the mechanical properties

Mast cell derived carboxypeptidase A3 is decreased among patients with advanced coronary artery disease

Background: Coronary artery disease (CAD) affects milions of people and can result in myocardialinfarction (MI). Previously, mast cells (MC) have been extensively investigated in the context of hypersensitivity,however as regulators of the local inflammatory response they can potentially contribute toCAD and/or its progression. The aim of the study was to assess if serum concentration of MC proteases:carboxypeptidase A3, cathepsin G and chymase 1 is associated with the extension of CAD and MI.Methods: The 44 patients with angiographically confirmed CAD (23 subjects with non-ST-segmentelevation MI [NSTEMI] and 21 with stable CAD) were analyzed. Clinical data were obtained as wellserum concentrations of carboxypeptidase A3, cathepsin G and chymase 1 were also measured.Results: Patients with single vessel CAD had higher serum concentration of carboxypeptidase thanthose with more advanced CAD (3838.6 ± 1083.1 pg/mL vs. 2715.6 ± 442.5 pg/mL; p = 0.02). Therewere no significant differences in levels of any protease between patients with stable CAD and those withNSTEMI. Patients with hypertension had ≈2-fold lower serum levels of cathepsin G than normotensiveindividuals (4.6 ± 0.9 pg/mL vs. 9.4 ± 5.8 pg/mL; p = 0.001). Cathepsin G levels were also decreasedin sera of the current smokers as compared with non-smokers (3.1 ± 1.2 ng/mL vs. 5.8 ± 1.2 ng/mL,p = 0.02).Conclusions: Decreased serum level of carboxypeptidase is a hallmark of more advanced CAD. Lowerserum levels of carboxypeptidase A3 and catepsin G are associated with risk factors of blood vessel damagesuggesting a protective role of these enzymes in CAD

AFP Performance in the Low Pile-up Runs

Since 2016 ATLAS detector is equipped with new devices - ATLAS Forward Proton (AFP) detectors. AFP aims to measure protons scattered at very small angles, which are a natural signature of so-called diffractive events. Measurement of properties of diffractive events usually require low pile-up data-taking conditions. AFP performance in such special, low pile-up runs, including evaluation of detector efficiency, will be presented

Overview of ATLAS forward proton detectors: status, performance and new physics results

A key focus of the physics program at the LHC is the study of head-on proton-proton collisions. However, an important class of physics can be studied for cases where the protons narrowly miss one another and remain intact. In such cases, the electromagnetic fields surrounding the protons can interact producing high-energy photon-photon collisions. Alternatively, interactions mediated by the strong force can also result in intact forward scattered protons, providing probes of quantum chromodynamics. We will briefly describe the layout and performance of ATLAS Forward Proton Detectors (AFP and ALFA) installed close to the LHC beam pipe far downstream of the interaction point, designed to measure positions and arrival times of protons scattered through very small angles. A novel search for axion-like particles decaying to two photons produced in photon-photon collisions using AFP detector will be highlighted. If available, diffractive measurement with forward protons using the latest ATLAS Run3 data will be also shown

Charged hadron production in central Ar+Sc collisions at the CERN SPS

Research Objectives The main goal of this work was to identify and obtain spectra of charged hadrons produced in Ar+Sc interactions at six beam momenta in the range of 13A-150A GeV/c. The project is a vital part of the NA61/SHINE programme, which main research goal is to study the collisions of intermediate systems, searching for the signatures of the onset of deconfinement and the critical point. Measured properties of hadron production in Ar+Sc collisions suggest that this particular reaction is on the boundary between "heavy" and "light" sys- tems. Ar+Sc may be the smallest of studied systems, in which colliding nu- cleons create not a number of isolated N+N events, but a collectively evolving fireball, with a possible formation of quark-gluon plasma at top SPS energies. Methodology Collisions of Ar+Sc were recorded in 2015 by the NA61/SHINE Collabora- tion. The work presented in this thesis involves the selection of events in terms of quality and physics relevance, identification of the most abundant charged hadrons and calculation of their kinematic spectra. The final results of this thesis deliver key information on the properties of π + , π − , K + , K − , p, and p̄ pro- duced in strong and electromagnetic interactions in the most central collisions of Ar+Sc. The spectra in transverse momentum and rapidity were measured for each of the listed particle species and mean multiplicities of charged kaons were calculated. Impact on studies of strongly interacting matter The project presented in this dissertation delivers important information on the influence of the sizes of colliding ions on the properties of hadron pro- duction. In particular, the measurement of strangeness production (K + /π + ) in Ar+Sc establishes a puzzling system size dependence, that none of the com- monly used theoretical models can reproduce, therefore motivating further phenomenological studies. Similarly, measured longitudinal spectra of protons and anti-protons provide interesting input for studies of the equation of state in a baryon-rich medium. Broader knowledge about system size dependence of hadron production properties will surely bring important insight into the basic properties o

ATLAS Forward Proton Detectors - Special 2017 Low Pile-up Runs

The performance of the ATLAS Forward Proton (AFP) Silicon Tracker detector is studied using the dedicated low-luminosity ATLAS LHC data collected in the 2017 running period of LHC Run~2. A brief description of the AFP spectrometer is given, followed by the discussion of unique opportunities of diffractive physics studies in low pile-up conditions. Additionally, some features of 2017 data are explored, including trigger efficiency and creation of particle showers within the detectors