ESR position 4 - Leiden The Netherlands

Group Description

ESR #4


PAHs and the organic inventory of meteorites and comets



Host Institute: Leiden Observatory, University of Leiden

Host Country: The Netherlands

Start date: No later than summer of 2017


The candidate will be employed at the Leiden Observatory and will read for a doctorate degree under the supervision of prof. Xander Tielens.


Project description

Carbonaceous meteorites and comets show a varied organic composition which is thought to reflect, at least partly, a heritage that dates back to interstellar clouds. However, a variety of processes on the parent asteroidal body and the comet will have modified any inherited material, including thermal processing in an aqueous or icy environment as well as processing by energetic ions and photons in the presence of nanograins. PAHs are one key component in the interstellar medium. The graduate student will develop models for the chemical evolution of PAHs in an aqueous environment and apply this to asteroids in the early solar system as well as for the photochemical evolution of ices and apply this to comets in the early solar system. He/she will identify chemical markers for these processes, make predictions for ALMA and JWST observations, and assess the astronomical implications by comparison to meteoritic and cometary composition.

As part of the study, secondments are foreseen to Heriot Watt University to study the characteristics of functionalized PAHs in ices, to Aarhus University to study the stability and catalytic activity of functionalized PAHs and to Graphic Science for the outreach project and travelling exposition development.




The interstellar medium group at Leiden observatory studies the origin and evolution of the organic inventory of space and combins that with studies on the structure and evolution of the interstellar medium of galaxies. In addition, we have an active program on the coagulation of dust particles, to aggregates, pebbles, and larger bodies in the general ISM and in protoplanetary disks. Leiden Observatory is actively involved in a large number of astronomical observing facilities, both ground and space based. Observations and modeling studies are supported by in house laboratory studies. It has a very active research program concerning Polycyclic Aromatic Hydrocarbon molecules in Space, analysis and interpretation of space-based infrared data, simulations of inter- and circumstellar conditions, controlled growth of pure or mixed interstellar ice analogs and simulation of chemical processes that occur in and on top of the ice.

Ideal Candidate


The position is open to students with the equivalent of a masters degree in astronomy, physics, physical chemistry, or Earth sciences. The successful student should have experience in experimental physics or computational chemistry preferably in one or more of the following areas: Raman and IR spectroscopy, density functional theory. A sound background in molecular astrochemistry is required, as is a good working knowledge in English. Certain restrictions on nationality apply related to mobility requirements from the Marie Curie Program.

Institute Description

Leiden University is a prominent research university in Europe, situated for decades in the top 100 of best Universities world wide, with approximately 17000 students and 4000 staff members. The university consists of 6 faculties, a School of education, and a campus in The Hague and focuses on the independent practice of research-oriented work in an academic setting. Leiden Observatory is one of the largest academic observatories in the world and ranked in the top 5. It has a very active research programme with 25 scientific staff, 45 post-docs, 80 graduate students and 40 master students. Bachelor and master courses are ETCS courses.

Working condition and benefits

The appointment is for 4 years and is anticipated to end with a Ph. D. degree at the Leiden University. The initial appointment is for one year and your performance will be evaluated after 6 months. After a positive evaluation, the appointment will be extended for the full period. The monthly gross salary of the first three years will be in accordance with the EC Marie Sklodowska-Curie rates and will be paid by the host organization. The fourth year follows the Dutch CAO for PhD students.The salary will be subjected to tax according to applicable national regulations.


Leiden University

The Netherlands

Supervisor: prof. Xander Tielens

Phone: +31 (0)71 527 8465

Email: tielens (@) strw (dot) leidenuniv (dot) nl

Address: P.O. Box 9513, NL 2300 RA Leiden



EUROPAH is a Marie Skłodowska-Curie action funded by the EU under the Horizon2020 framework, grant number 722346



Aarhus University, 120 Ny Munkegade, Aarhus 8000 Denmark


T. 0045 8775 5584



Copyright @ All rights reserved