Kinematics of local and high-z galaxies through 3D modeling of emission-line datacubes

The kinematics is a fundamental tool to infer the dynamical structure of galaxies and to understand their formation and evolution. Spectroscopic observations of gas emission lines are often used to derive rotation curves and velocity dispersions. It is however difficult to disentangle these two quantities in low spatial-resolution data because of beam smearing. In this thesis, we present 3D-Barolo, a new software to derive the gas kinematics of disk galaxies from emission-line data-cubes. The code builds tilted-ring models in the 3D observational space and compares them with the actual data-cubes. 3D-Barolo works with data at a wide range of spatial resolutions without being affected by instrumental biases. We use 3D-Barolo to derive rotation curves and velocity dispersions of several galaxies in both the local and the high-redshift Universe. We run our code on HI observations of nearby galaxies and we compare our results with 2D traditional approaches. We show that a 3D approach to the derivation of the gas kinematics has to be preferred to a 2D approach whenever a galaxy is resolved with less than about 20 elements across the disk. We moreover analyze a sample of galaxies at z~1, observed in the H-alpha line with the KMOS/VLT spectrograph. Our 3D modeling reveals that the kinematics of these high-z systems is comparable to that of local disk galaxies, with steeply-rising rotation curves followed by a flat part and H-alpha velocity dispersions of 15-40 km/s over the whole disks. This evidence suggests that disk galaxies were already fully settled about 7-8 billion years ago. In summary, 3D-Barolo is a powerful and robust tool to separate physical and instrumental effects and to derive a reliable kinematics. The analysis of large samples of galaxies at different redshifts with 3D-Barolo will provide new insights on how galaxies assemble and evolve throughout cosmic time.

Diversity and local democracy. The case of Republic of Macedonia - implications of ethnic diversity on municipal decision making and organizational performance

This research seeks to review the level of knowledge achieved in interpreting the relationship between the ethnic diversity at the workplace in the public sector and the organizational performance; as well as seeks to contribute in understanding the implications of this relationship. The study commenced with investigating the academic research in the relevant area addressing the following research questions: (a) How are diversity management and organizational performance conceptualized? (b) What are the existing findings of research concerning diversity at the workplace in the public organizations and organizational performance? (c) What factors intervene the relationship between the diversity and organizational performance? Based on the findings from the review of the academic research, this study seeks to contribute in understanding the ethnic diversity – performance relationship and its mplications at the local level in the Macedonian context. The reform process in Macedonia as a multicultural society, where for many years, inter-ethnic relations have been one of the most sensitive political issues, affecting both the stability of the country and the progress, focused mainly on the implementation of the decentralization and inclusion of ethnic minorities in the decision making process. With the implementation of the Ohrid Framework Agreement workforce at the units of local self-government in Republic of Macedonia is becoming more balanced with respect to ethnic minorities, with more workforce participation than ever by Albanians, Turks, Roma and other minorities. As public organizations at local level become more diverse along ethnic lines, it makes sense to pay more attention to how different ethnic groups interact with one another at work. Thus it gives additional importance on the research question addressed in the study and gives significance of the research in a broader scope.