New measurement of pion directed flow relative to the spectator plane by the NA49 experiment at CERN

We report a new measurement of negatively charged pion directed flow $v_1$ relative to the spectator plane for Pb+Pb collisions at the beam energy 40A GeV recorded by the NA49 experiment at CERN. $v_1$ is reported as a function of rapidity and transverse momentum in different classes of collision centrality. The projectile spectator plane is estimated using transverse segmentation of the NA49 forward hadron calorimeter. The new results extend the NA49 data for $v_1$, which was previously measured only relative to the participant plane, and complement recent preliminary data by the NA61/SHINE collaboration and published results from the STAR at RHIC beam energy scan program.Comment: Proceedings of the XIII Workshop on Particle Correlations and Femtoscopy (WPCF 2018), 6 pages, 3 figure

Estimating non-flow effects in measurements of directed flow of protons with the HADES experiment at GSI

Centrality dependence of the directed flow of protons in Au+Au collisions at the beam energy of 1.23A GeV collected by the HADES experiment at GSI is presented. Measurements are performed with respect to the spectators plane estimated using the Forward Wall hodoscope. Biases due to non-flow correlations and correlated detector effects are evaluated. The corresponding systematic uncertainties are quantified using estimates of the spectators plane from various forward rapidity regions constructed from groups of Forward Wall channels and protons reconstructed with the HADES tracking system.Comment: Proceedong for the LXX International conference "NUCLEUS - 2020. Nuclear physics and elementary particle physics. Nuclear physics technologies

THERMODYNAMIC ASPECTS OF CORROSION BEHAVIOR OF STEELS IN LEAD MELTS CONTAINING OXYGEN

Термодинамическими расчетами проведена оценка устойчивости оксидов основных легирующих элементов стали в расплавах Pb, содержащих кислород, в диапазоне температур от 400 до 800 оС. Определены границы областей по температуре и содержанию кислорода в Pb, соответствующие существованию однослойных оксидных пленок, состоящих из железо-хромистой шпинели Cr2FeO4 и двухслойных оксидных пленок из магнетита Fe3O4 и шпинели Cr2FeO4. Получены выражения для определения содержания кислорода в Pb, соответствующие линиям равновесия оксидных фаз основных легирующих элементов сталей в зависимости от температуры. Построена диаграмма, позволяющая проводить градацию и группировку экспериментальных данных по механизмам протекания коррозионных процессов.Thermodynamic calculations were used to assess the stability of oxides of the main alloying elements of steel in Pb melts containing oxygen in the temperature range from 400 to 800 °C. The boundaries of the regions by temperature and oxygen content in lead corresponding to the existence of singlelayer oxide films consisting of iron-chromium spinel Cr2FeO4 and two-layer oxide films of magnetite Fe3O4 and spinel Cr2FeO4 are determined. Expressions for determining the oxygen content in Pb corresponding to the equilibrium lines of the oxide phases of the main alloying elements of steels as a function of temperature are obtained. A diagram is constructed that allows gradation and grouping of experimental data on the mechanisms of corrosion processes

Data-Driven Methods for Spectator Symmetry Plane Estimation in CBM Experiment at FAIR

The Compressed Baryonic Matter experiment (CBM) at FAIR aims to study the area of the QCD phase diagram at high net baryon densities and moderate temperatures with collisions of heavy ions at sNN=2.8–4.9 GeV. The anisotropic transverse flow is one of the most important observable phenomena in a study of the properties of matter created in such collisions. Flow measurements require the knowledge of the collision symmetry plane, which can be determined from the deflection of the collision spectators in the plane transverse to the direction of the moving ions. The CBM performance for projectile spectator symmetry plane estimation is studied with GEANT4 Monte Carlo simulations using collisions of gold ions with beam momentum of 12A GeV/c generated with the DCM-QGSM-SMM model. Different data-driven methods to extract the correction factor in flow analysis for the resolution of the spectator symmetry plane estimated with the CBM Projectile Spectator Detector are investigated

Estimating non-flow effects in measurements of directed flow of protons with the HADES experiment at GSI

Centrality dependence of the directed flow of protons in Au+Au collisions at the beam energy of 1.23A GeV collected by the HADES experiment at GSI is presented. Measurements are performed with respect to the spectators plane estimated using the Forward Wall hodoscope. Biases due to non-flow correlations and correlated detector effects are evaluated. The corresponding systematic uncertainties are quantified using estimates of the spectators plane from various forward rapidity regions constructed from groups of Forward Wall channels and protons reconstructed with the HADES tracking system

Analysis of anisotropic transverse flow in Pb-Pb collisions at 40A GeV in the NA49 experiment

Anisotropic transverse flow is one of the most important observables in the study of ultra-relativistic nucleus-nucleus collisions. Detector acceptance non-uniformity in the transverse plane introduces substantial bias in the flow analysis dictating the need for specific corrections. The results of flow analysis in Pb-Pb collisions at the beam energy of 40$A$~GeV recorded with the fixed target experiment NA49 at the CERN SPS are presented. The three-subevent technique is used for the differential measurements of the directed and elliptic flow. Corrections for the detector acceptance anisotropy in the transverse plane are applied using an extension of the Qn-Corrections Framework developed originally for the ALICE experiment at the LHC. The results are compared with those previously published by the STAR at RHIC and the NA49 at CERN SPS collaborations. In the future, the developed procedure will be used for the analysis of the new Pb-Pb data collected by the NA61/SHINE experiment at the CERN SPS.Anisotropic transverse flow is one of the most important observables in the study of ultra-relativistic nucleus-nucleus collisions. Detector acceptance non-uniformity in the transverse plane introduces substantial bias in the flow analysis dictating the need for specific corrections. The results of flow analysis in Pb-Pb collisions at the beam energy of 40 A GeV recorded with the fixed target experiment NA49 at the CERN SPS are presented. The three-subevent technique is used for the differential measurements of the directed and elliptic flow. Corrections for the detector acceptance anisotropy in the transverse plane are applied using an extension of the Qn-Corrections Framework developed originally for the ALICE experiment at the LHC. The results are compared with those previously obtained by the STAR at RHIC and the NA49 at CERN SPS collaborations. In the future, the developed procedure will be used for the analysis of the new Pb-Pb data collected by the NA61/SHINE experiment at the CERN SPS

Data-Driven Methods for Spectator Symmetry Plane Estimation in CBM Experiment at FAIR

The Compressed Baryonic Matter experiment (CBM) at FAIR aims to study the area of the QCD phase diagram at high net baryon densities and moderate temperatures with collisions of heavy ions at sNN=2.8–4.9 GeV. The anisotropic transverse flow is one of the most important observable phenomena in a study of the properties of matter created in such collisions. Flow measurements require the knowledge of the collision symmetry plane, which can be determined from the deflection of the collision spectators in the plane transverse to the direction of the moving ions. The CBM performance for projectile spectator symmetry plane estimation is studied with GEANT4 Monte Carlo simulations using collisions of gold ions with beam momentum of 12A GeV/c generated with the DCM-QGSM-SMM model. Different data-driven methods to extract the correction factor in flow analysis for the resolution of the spectator symmetry plane estimated with the CBM Projectile Spectator Detector are investigated

Anisotropic flow measured in Pb-Pb collisions with the NA49 and NA61/SHINE experiments at CERN SPS

Results are presented for directed flow v 1 of negatively charged pions measured relative to the spectator plane in Pb+Pb collisions at the beam energy 40A GeV recorded by the NA49 experiment at CERN. The measurements were performed as a function of rapidity and transverse momentum in two classes of collision centrality. The projectile spectator symmetry plane is estimated using the transverse segmentation of the forward hadron calorimeters. Analysis details related to event selection and particle identification are provided along with a description of the procedure used to apply corrections for the limited detection efficiency. Additionally a systematic study of effects due to detector non-uniformity on pion directed flow measurement is presented

New measurement of pion directed flow relative to the spectator plane by the NA49 experiment at CERN

We report a new measurement of negatively charged pion directed flow $v_1$ relative to the spectator plane for Pb+Pb collisions at the beam energy 40A GeV recorded by the NA49 experiment at CERN. $v_1$ is reported as a function of rapidity and transverse momentum in different classes of collision centrality. The projectile spectator plane is estimated using transverse segmentation of the NA49 forward hadron calorimeter. The new results extend the NA49 data for $v_1$, which was previously measured only relative to the participant plane, and complement recent preliminary data by the NA61/SHINE collaboration and published results from the STAR at RHIC beam energy scan program

Effects of the detector non-uniformity in pion directed flow measurement relative to the spectator plane by the NA49 experiment at the CERN SPS

Results are presented for directed flow υ1 of negatively charged pions measured relative to the spectator plane in Pb+Pb collisions at the beam energy 40A GeV recorded by the NA49 experiment at CERN. The measurements were performed as a function of rapidity and transverse momentum in two classes of collision centrality. The projectile spectator symmetry plane is estimated using the transverse segmentation of the forward hadron calorimeters. Analysis details related to event selection and particle identification are provided along with a description of the procedure used to apply corrections for the limited detection efficiency. Additionally a systematic study of effects due to detector non-uniformity on pion directed flow measurement is presented