This thesis presents the anharmonic infrared spectra of a series of polycyclic aromatic hydrocarbons. Comparisons and characterizations are made based on high-resolution low-temperature gas-phase experimental spectra.

This thesis is about the study of hydrocarbons via infrared spectroscopy.

We have conducted a full spectral line survey of the 3-13 micron region of two massive protostars, AFGL 2591 and AFGL 2136, for the first time at high spectral resolution.

Promotor: I. A. G. Snellen, Co-promotor: M. A. Kenworthy

An Active Galactic Nucleus (AGN) is a highly luminous region at the center of a galaxy, powered by the accretion into a supermassive black hole and emitting energy from radio waves to gamma rays, often outshining the host galaxy.

The Dutch-Japanese made DESHIMA instrument has passed its first practical tests when measuring the distances and ages of distant galaxies. The core of the instrument is a chip the size of two euro coins that measures 49 shades of far infrared light. The developers of the spectrometer publish the results…

Large areas of space are filled by molecular clouds that consist of gas and dust grains that are the remnants of dead stars. When these clouds start collapsing, the decreasing temperature and increasing density cause gas particles to start accreting onto dust grain surfaces.

Bernhard Brandl, the new Leiden Professor of Infrared Astronomy, is developing instruments for the world’s largest telescopes. These telescopes can be used to observe objects in space that are more than 13 billion years old. Brandl will deliver his inaugural lecture on 26 September.

After 25 years, this December will finally see the launch of the long-awaited James Webb space telescope (JWST). Leiden astronomers are watching with great excitement: not only were they involved in the construction of important instruments on board, but the telescope will also reveal many new secrets…

Astronomers from Leiden University have discovered that the star wind from a newborn star in the Orion Nebula prevents more stars from forming in the immediate vicinity. They made the discovery with data from the SOFIA observatory. This was announced by co-author Xander Tielens during a press conference…

NASA’s telescope SOFIA has provided a new glimpse of the chemistry in the inner region surrounding massive young stars where future planets could begin to form. Leiden PhD candidate Andrew Barr writes about it in the Astrophysical Journal. The scientists found massive quantities of water and organic…

An international team of astronomers led by scientists from Leiden Observatory has for the first time characterised a dust disk surrounding a young super-Jupiter, which is either a giant planet or brown dwarf. They detected infrared emission from the disk which might indicate that moons may have formed.…