Two 4 yrs PhD positions in the field of astrochemistry
VACANCY 1: Ice Spectroscopy, in the laboratory and with JWST
We have a 4 yrs (1+3 yrs) PhD vacancy to work with IRASIS, one of the ice setups in the laboratory for astrophysics at Leiden Observatory and data interpretation of upcoming JWST ice
data. Laboratory and observational work are roughly 70-30.
The project comprises the systematic vibrational characterization of astrophysically relevant molecules embedded in chemically related ice matrices. This work is in support of JWST data that will become available through more than 150 hours of guaranteed observing time within MIRI-GTO, Early Release Science (ICE AGE), and GO programs.
We are looking for an enthusiastic person, with a good background in experimental physics/chemistry and a strong interest in astronomical data interpretation. The successful candidate has recently obtained her/his master degree or will do very soon. Very good English skills are a prerequisite.
The work is performed in the Laboratory for Astrophysics at Leiden Observatory at Leiden Observatory under supervision of Profs. Harold Linnartz, Ewine van Dishoeck and Dr. Melissa McClure. The candidate will be will be part of a larger international team studying the physical and chemical structure and evolution of protostars and planet-forming disks with JWST and ALMA.
We take applications up to July 6 and aim for a start in early 2022.
Please send your application (motivation letter, cv, grades), together with the names of two persons who can provide a letter of recommendation
to email@example.com, firstname.lastname@example.org and email@example.com.
Leiden Observatory is a lively institute carrying out observational, interpretative and theoretical research in the fields of the star and planet formation, astrochemistry, laboratory astrophysics, exoplanets, the formation, dynamics and evolution of (high-redshift) galaxies and their nuclei, and cosmology.
The links below provide additional information. More detailed info can be provided upon request.
- Laboratory for astrophysics: http://www.laboratory-astrophysics.eu
- ERS ICE AGE: http://jwst-iceage.org/
- MIRI GTO programme: https://www.stsci.edu/jwst/science-execution/program-information?id=1290
- Leiden Observatory: http://wwww.local.strw.leidenuniv.nl
VACANCY 2: Computationally unraveling energy dissipation on CO ices
We have a 4 yrs (1+3 yrs) PhD vacancy to work on energy dissipation of CO ices within an astrochemical framework at the Theoretical Chemistry department of Leiden University. A strong link with ongoing work at the Laboratory for Astrophysics (LfA) at Leiden Observatory is foreseen and there will be the possibility of applying for beam time at the FELIX facility at Radboud University Nijmegen for complementary experimental work.
The project comprises the implementation of a force field for initially pure CO ices in python (Atomic Simulation Environment) to allow the systematic characterization of the energy flow of particular vibrational modes into the ice cluster. This project is envisioned to expand by studying the influence of including isotope effects and implementing periodic boundary conditions such that also bulk crystaline ices can be studied.
We are looking for an enthusiastic person, with a good background in programming with python (or other languages), a physics or chemistry degree and a strong interest in astrochemistry. Experience or affinity with experimental work is preferred, but not strictly required. The successful candidate has recently obtained a master degree or will do very soon. Very good English skills are a prerequisite.
The work will be performed at the Leiden Institute of Chemistry (LIC) under supervision of Dr. Thanja Lamberts in collaboration with Dr. Jörg Meyer (LIC) and Prof. Harold Linnartz (LfA). Within the Theoretical Chemistry group ample knowledge transfer is expected in the field of solid-state computational chemistry. Through linking with Leiden Observatory the candidate will be in close connection with state-of-the-art research on various aspects of astrochemistry, ranging from the Laboratory perspective to observations with JWST and ALMA.
We take applications up to July 6 and aim for a start in early 2022.
Please send your application (motivation letter, cv, grades), together with the names of two persons who can provide a letter of recommendation to Dr. Lamberts (firstname.lastname@example.org) with Prof. Linnartz in CC (email@example.com).
The chemistry and life science research in the Leiden Institute of Chemistry (LIC) is organized around two major research areas: 'Chemical Biology' and 'Energy & Sustainability'. The institute's research themes illustrate the central position of chemistry between biology, medicine and physics. The various research topics carried out within these themes are ideal for executing interdisciplinary research. For more information, see www.universiteitleiden.nl/en/science and http://workingat.leiden.edu/
More detailed info can be provided upon request.
Splinter session: Impact of Cosmic Rays on the Physics and Chemistry of Dense Molecular Gas
The splinter session "Impact of Cosmic Rays on the Physics and Chemistry of Dense Molecular Gas" will be held as part of the Astronomische Gesellschaft 2021 conference. This conference will be virtual this year. This splinter session is meant to bring together experts in astrochemistry, star formation, and cosmic-ray transport.
Splinter session date: Monday September 13, 09:00-13:00 CEST (UTC+2)
Abstract submission deadline: August 15, 2021
Cosmic rays (CRs) are energetic charged particles that are accelerated in extreme environments. In dense molecular gas that is shielded from external UV radiation, the ionization of atoms and molecules by CRs plays a crucial role in driving chemical and physical processes as well as in affecting the emission of ionic, atomic and molecular lines. At high column densities, CRs ionize H2 initiating a diverse chemistry through fast ion-neutral reactions. The interaction of CRs with the dense gas induces UV photons via H2 electronic excitation. These influence the chemistry in icy grain mantles, as does the deposition of energy by direct CR bombardment. In chemical models, the above processes are controlled by the so-called “cosmic-ray ionization rate”, ζ, making it one of the most important parameters for the underlying physics and chemistry of dense gas. In molecular clouds, ζ is most sensitive to the flux of low-energy CRs (1–100 MeV). However, the transport of low-energy CRs through dense gas is poorly constrained, and estimates of ζ in such regions are highly uncertain. Furthermore, recent observations in dense cores suggest a conflict with current cosmic-ray transport models. Therefore, understanding both the transport of CRs and the chemistry they drive is vital. During this splinter session, we will bring together researchers across a range of communities, including astrochemists and cosmic-ray transport modellers. These communities do not often meet together, despite how intertwined the research can be. We will focus on talks by junior researchers and develop an interdisciplinary session. We anticipate a fruitful discussion which will help the astrochemical, star formation and high-energy astrophysics communities.
Important questions that will be discussed during this session will be:
- What is the impact of cosmic-rays on gas- and ice-phase chemistry, particularly in regions with high cosmic-ray ionization rates?
- What are the best observations and calibrations to constrain the cosmic-ray ionization rate?
- How do low-energy cosmic rays transport through dense molecular gas? What observations need to be done to constrain this?
- Is there an observable correlation between the star-formation rate and the cosmic-ray ionization rate?
- Looking forward: what kinds of observational facilities and instruments and theoretical models are needed to constrain the transport of low-energy cosmic rays and the cosmic-ray ionization rate in dense gas?