27220 - Atoms and Molecules in the Cosmos

Learning outcomes

The students learn: 1) to predict, on the basis of the photophysical and thermodynamical conditions of the different astronomical scenarios, the expected processes of molecular formation and disctruction and their kinetics; 2)  to predict, on the basis of the energy diagrams of atoms, ions, and simple molecules, the spectral activity in the cosmic laboratory.

Course contents

The Interstellar Medium (ISM)

• Constituents, structure, evolution.
• Survey of detected molecules.

Molecular spectroscopy

• Interaction of radiation with matter. Transitions probabilities and selection rules.
• Rotational spectroscopy: spectra of linear, symmetric-top, and asymmetric molecules; hyperfine structure.
• Vibrational spectroscopy: harmonic and anaharmonic oscillators, the vibro-rotation spectrum; spectra of polyatomic molecules.
• Electronic spectroscopy: description of electronic states and their vibrational and rotational structure; forbidden and allowed transitions; dissociation and predissociation.

Interstellar chemistry

• Molecular Hydrogen: formation and destruction in the ISM.
• Chemical routes to interstellar molecules.
• Molecules in the Milky Way Galaxy: in diffuse and dark clouds, in star-forming regions, in near-stellar environments.
• The path to planets: ionization, chemistry during the collapse and in protoplanetary disks, comets, meteroids, exoplanets.
• Primordial chemistry.
• Astrochemical modeling.

Readings/Bibliography

• Lecture notes.
• J. M. Brown, Molecular Spectroscopy, Oxford University Press, 1998.
• T.W. Hartquist & D.A. Williams, The Chemically Controlled Cosmos, Cambridge University Press, 1995.
• D.A. Williams & T.W. Hartquist, The Cosmic-Chemical Bond, RSCPublishing, 2013
• S. Kwok, Physiscs and Chemistry of the Interstellar Medium, University Science Books, 2007

Teaching methods

Classes are organized as lectures in the classroom, and laboratory exercises.

Assessment methods

Learning assessment is evaluated only by means of the final examination. This aims at verifying the student's knowledge and skills by means of an oral exam, where the student presents a short thesis and replies to questions concerning the course contents.

Teaching tools

Video projector, notebook, blackboard.

Office hours

See the website of Luca Dore