96396 - Resolved Stellar Populations

Learning outcomes

The course presents a general overview of the main properties of resolved stellar populations. At the end of the course, the student has deep insight in both observational and theoretical topics concerning resolved stellar populations. The student is able to critically discuss the main indicators of metallicity, age and distance, has knowledge of the current scenarios for the formation and evolution of exotic populations, as blue stragglers and millisecond pulsars, and masters general concepts about the internal dynamical evolution of multi-body stellar systems.

Course contents

• Main properties of resolved stellar populations: globular clusters, open clusters, local galaxies.
• Connection between theory and observations: evolutionary sequences in the HR diagram and in the color-magnitude diagram, isochrones, reddening, distance modulus, bolometric corrections.
• Metallicity estimate from the photometric properties of resolved stellar populations. Simple and complex stellar populations.
• Age and distance indicators in resolved stellar populations.
• The complex morphology of the Horizontal Branch.
• Spectral Energy Distribution (SED), Fuel Consumption theorem and Phase transitions in simple stellar populations and their use for the interpretation of unresolved systems.
• Multiple stellar populations in globular clusters.
• Globular cluster internal dynamics and dynamical evolution.
• "Exotic" stellar populations: blue straggler stars, optical companions to millisecond pulsars, intermediate-mass black holes

Readings/Bibliography

The final exam can be prepared using the notes taken during the lessons and the Lecture Notes made available by the teacher at the web site "Virtuale UniBO" of the Bologna University. Hence, attending in person is strongly recommended for a successful acquisition and understanding of the discussed topics. In addition, the attending student will have opportunity to ask questions during the lessons, for a full comprehension of the course content.

Additional scientific papers are suggested during the classes and can be used to improve knowledge. These can be downloaded at the dedicated web sites. For instance: http://cdsads.u-strasbg.fr/abstract_service.html

Additional textbooks useful for further deepening the knowledge of specific topics are the following:

Evolution of stars and stellar populations - Salaris & Cassisi

An Introduction to modern Astrophysics - Carroll & Ostlie

Astrophysics I. stars - Bowers& Deeming

Teaching methods

Class lectures are made with the support of power-point presentations. The lessons provide explanation of astrophysical concepts specific to resolved stellar populations and observational astronomy, helped with images and graphs aimed at improving the comprehension.

Assessment methods

The final exam aims at verifying the student’s knowledge and understanding of the topics explained during the lessons, and their skills of organizing the answers (distinguishing the main, fundamental points from second-order details) and expressing them-selves using appropriate (scientific) language.

It is an oral exam, typically lasting 40-45 minutes. During the first 10 minutes, the students will be asked to discuss a topic on their own choice. The main purpose is to verify the student's ability to explain in a clear, synthetic and well-organized manner a known topic within the available time slot (10 min). Then, they will be asked to answer to 3-4 more questions on the entire program discussed during the lessons.

The final grade will be set based on the following scheme:

• grade=18-21: the knowledge is limited to just a small sub-sample of topics and the student answers to the questions only with a substantial help from the teacher

• grade=22-25: the knowledge concerns a larger number of topics, and the student answers the questions with some teacher help

• grade=26-28: the student is able to discuss most of the topics and answer the questions with good autonomy and critical sense, showing some uncertainties only on second-order points

• grade=29-30L: the student shows solid and deep knowledge and excellent understanding of all the topics, answering to all questions readily and with very good mastery of the scientific terminology

During the exam, students are not allowed to use notes and books.

The students have the opportunity to refuse the assigned grade at most 2 times. Then, the last obtained grade (not the best one) will be registered.

Students with learning disabilities or temporary or permanent disabilities: please contact the relevant University office promptly (https://site.unibo.it/studenti-con-disabilita-e-dsa/en). The office will advise students of possible adjustments, that will be submitted to the professor for approval 15 days in advance. The professor will evaluate their suitability also in relation to the academic objectives of the course.

Teaching tools

Lectures are performed with power-point presentations. The slides are updated and made available to the students every year on the dedicates web site "Virtuale UniBO" of the Bologna University

Office hours

See the website of Barbara Lanzoni