Observational Astrophysics

This module provides an introduction into observational methods towards the universe and its objects. Telescopes, experiments, and their methods are discussed per messenger type, and application towards their characteristic astrophysical studies is discussed. In particular, we address:

• Which are the relevant astrophysics quests, and which cosmic messengers do we know?
• What are components of cosmic matter, and its observables?
• Which radiation processes occur in sources and objects, how does radiation transport work up to the observer?
• Which instruments, telescopes, experiments are available or can be made? From radio to gamma rays, neutrinos, cosmic rays, meteorites, gravitational waves.
• How do stars form, evolve, and explode, which are the compact remnants?
• Which compact objects do we know; how do processes/phenomena such as accretion, magnetars, bursts, mergers relate to these?
• Which components characterise the interstellar medium? What are the roles of cold gas and dust, hot and relativistic plasma, cosmic rays?
• Which galaxies of different types do we distingiush, what are their characteristic objects and sources?
• What are the key literature and databases on the astronomical window/discipline and projects?

After successful completion of the module, students are able to

• associate physical processes in cosmic objects to their specific observational method(s).
• understand the design and the critical components of telescopes, from radio through IR and optical to x- and gamma radiation, as well as the instruments for cosmic dust, cosmic rays, gravitational waves, and neutrinos.
• describe the evolution of normal and exotic stars, from formation through different phases until their remnants.
• explain the physics of different, sometimes violent, energy release processes in cosmic objects.
• assess the observability gaps in view of standard theories describing the universe.

No preconditions in addition to the requirements for the Master’s program in Physics.

In classroom lectures the teaching and learning content is presented and explained in a didactical, structured, and comprehensive form. This includes basic knowledge on the various astronomical messengers as well as selected current topics in astrophysics as discussed from these astronomical data, i.e. from a very broad research field. Universal methodic and physics concepts are highlighted by cross referencing between different topics. Crucial facts are conveyed by involving the students in scientific discussions to develop their intellectual power and to stimulate their analytic thinking on astrophysics problems. Regular attendance of the lectures is therefore expected and highly recommended.

The interpretational astrophysics examples as well as regular self-study of personal notes from the lectures and of textbooks and recent review articles referenced in the course are an important part of the learning process by the students. Such post-processing and practicing of the teaching content is indispensable to achieve the intended learning results that the students develop the ability of explaining and applying the learned knowledge independently.

Presentation (slides from Powerpoint/Keynote), with post-lecture PDFs provided online, supplemented by selected board teaching, and short contributions from students

• P. Lená, D. Rouan, F. Lebrun, F. Mignard & D. Pelat: Observational Astrophysics, Springer, (2012)
• D. Maoz: Astrophysics in a Nutshell, Princeton University Press, (2016)
• M.S. Longair: High-Energy Astrophysics, 3rd ed., Cambridge University Press, (2011)
• S. Rosswog & M. Brüggen: Introduction to High-energy Astrophysics, Cambridge University Press, (2007)

The achievement of the competencies given in section learning outcome is tested exemplarily at least to the given cognition level using presentations independently prepared by the students. The exam of 25 minutes consists of the presentation and a subsequent discussion.

For example an assignment in the exam might be:

• How does a supernova work?
• What characterises a gamma-ray burst, and which physical processes can one infer?
• What are the critical components of a radio telescope?