The Treiman-Yang Criterion: validating the Trojan Horse Method by experimentally probing the reaction mechanism

Proper selection of the quasi-free (QF) break-up channel in a three-body reaction is a key aspect for the applicability of the Trojan Horse Method (THM). The Treiman-Yang (TY) Criterion is a model-independent experimental test for the dominance of the QF mechanism, and hence constitutes one of the strongest validity tests of the THM. An experiment was performed at LNS to apply the test to the d(10B, 7Be α)n reaction. Here, the criterion is described and some preliminary data from the experiment are shown

Challenges in QCD matter physics - The Compressed Baryonic Matter experiment at FAIR

Substantial experimental and theoretical efforts worldwide are devoted to explore the phase diagram of strongly interacting matter. At LHC and top RHIC energies, QCD matter is studied at very high temperatures and nearly vanishing net-baryon densities. There is evidence that a Quark-Gluon-Plasma (QGP) was created at experiments at RHIC and LHC. The transition from the QGP back to the hadron gas is found to be a smooth cross over. For larger net-baryon densities and lower temperatures, it is expected that the QCD phase diagram exhibits a rich structure, such as a first-order phase transition between hadronic and partonic matter which terminates in a critical point, or exotic phases like quarkyonic matter. The discovery of these landmarks would be a breakthrough in our understanding of the strong interaction and is therefore in the focus of various high-energy heavy-ion research programs. The Compressed Baryonic Matter (CBM) experiment at FAIR will play a unique role in the exploration of the QCD phase diagram in the region of high net-baryon densities, because it is designed to run at unprecedented interaction rates. High-rate operation is the key prerequisite for high-precision measurements of multi-differential observables and of rare diagnostic probes which are sensitive to the dense phase of the nuclear fireball. The goal of the CBM experiment at SIS100 (sqrt(s_NN) = 2.7 - 4.9 GeV) is to discover fundamental properties of QCD matter: the phase structure at large baryon-chemical potentials (mu_B > 500 MeV), effects of chiral symmetry, and the equation-of-state at high density as it is expected to occur in the core of neutron stars. In this article, we review the motivation for and the physics programme of CBM, including activities before the start of data taking in 2022, in the context of the worldwide efforts to explore high-density QCD matter.Comment: 15 pages, 11 figures. Published in European Physical Journal

Measurement of global polarization of {\Lambda} hyperons in few-GeV heavy-ion collisions

The global polarization of {\Lambda} hyperons along the total orbital angular momentum of a relativistic heavy-ion collision is presented based on the high statistics data samples collected in Au+Au collisions at \sqrt{s_{NN}} = 2.4 GeV and Ag+Ag at 2.55 GeV with the High-Acceptance Di-Electron Spectrometer (HADES) at GSI, Darmstadt. This is the first measurement below the strangeness production threshold in nucleon-nucleon collisions. Results are reported as a function of the collision centrality as well as a function of the hyperon transverse momentum (p_T) and rapidity (y_{CM}) for the range of centrality 0--40%. We observe a strong centrality dependence of the polarization with an increasing signal towards peripheral collisions. For mid-central (20--40%) collisions the polarization magnitudes are (%) = 6.0 \pm 1.3 (stat.) \pm 2.0 (syst.) for Au+Au and (%) = 4.6 \pm 0.4 (stat.) \pm 0.5 (syst.) for Ag+Ag, which are the largest values observed so far. This observation thus provides a continuation of the increasing trend previously observed by STAR and contrasts expectations from recent theoretical calculations predicting a maximum in the region of collision energies about 3 GeV. The observed polarization is of a similar magnitude as predicted by 3D fluid dynamics and the UrQMD plus thermal vorticity model and significantly above results from the AMPT model.Comment: 8 pages, 4 figure

Wilsbekwaamheid bij mensen met een verstandelijke beperking

BACKGROUND: Mental competence is a complex concept within the contexts of ethics, law, psychology and medicine. Competency is a prerequisite for giving informed consent for a medical intervention. It has long been wrongly thought that people with intellectual disabilities as a group are incapacitated, but competence is not a categorical trait of a certain group of persons. Capacities can fuctuate over time and can vary per decision or action domain. The more severe the intellectual disability, the less likely that someone is competent in health care decision-making. AIM: To describe specifically the meaning of the concept of competence in people with intellectual disabilities and the legal frameworks in the Netherlands and Belgium. Furthermore, to provide practices for assessing competence and to focus on supporting competence in this target group. METHOD: Overview of the most recent theory and practical methods. RESULTS: The assessment of decision-making competence can be difficult and has far-reaching consequences, and must therefore be applied carefully and well-founded. CONCLUSION: It is advisable to support people with an intellectual disability in order to be able to make decisions themselves as much as possible

Wilsbekwaamheid bij mensen met een verstandelijke beperking

BACKGROUND: Mental competence is a complex concept within the contexts of ethics, law, psychology and medicine. Competency is a prerequisite for giving informed consent for a medical intervention. It has long been wrongly thought that people with intellectual disabilities as a group are incapacitated, but competence is not a categorical trait of a certain group of persons. Capacities can fuctuate over time and can vary per decision or action domain. The more severe the intellectual disability, the less likely that someone is competent in health care decision-making. AIM: To describe specifically the meaning of the concept of competence in people with intellectual disabilities and the legal frameworks in the Netherlands and Belgium. Furthermore, to provide practices for assessing competence and to focus on supporting competence in this target group. METHOD: Overview of the most recent theory and practical methods. RESULTS: The assessment of decision-making competence can be difficult and has far-reaching consequences, and must therefore be applied carefully and well-founded. CONCLUSION: It is advisable to support people with an intellectual disability in order to be able to make decisions themselves as much as possible

The Treiman-Yang Criterion: Validating the Trojan Horse Method by experimentally probing the reaction mechanism

Proper selection of the quasi-free (QF) break-up channel in a three-body reaction is a key aspect for the applicability of the Trojan Horse Method (THM). The Treiman-Yang (TY) Criterion is a model-independent experimental test for the dominance of the QF mechanism, and hence constitutes one of the strongest validity tests of the THM. An experiment was performed at LNS to apply the test to the d(10B, 7Be α)n reaction. Here, the criterion is described and some preliminary data from the experiment are shown

The Treiman-Yang Criterion: validating the Trojan Horse Method by experimentally probing the reaction mechanism

Proper selection of the quasi-free (QF) break-up channel in a three-body reaction is a key aspect for the applicability of the Trojan Horse Method (THM). The Treiman-Yang (TY) Criterion is a model-independent experimental test for the dominance of the QF mechanism, and hence constitutes one of the strongest validity tests of the THM. An experiment was performed at LNS to apply the test to the d(10B, 7Be α)n reaction. Here, the criterion is described and some preliminary data from the experiment are shown