Multiphoton ionization combining radiation from synchrotrons and free electron and optical lasers
The principal scientific goal of the mission was to allow the applicant (Patrick O’Keeffe, National Research Council of Italy, Rome) and the host (Michael Meyer, European XFEL Hamburg, Germany) to collaborate with Alexei Grum–Grzhimailo and Elena Gryzlova of the Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University in order to prepare a manuscript based on experimental results obtained during a beam time at the French synchrotron source, SOLEIL, on the two-photon resonant ionization of Xe combining synchrotron and optical laser light.
The novelty of the results lies in the fact that the angular distributions of the emitted electrons were measured in coincidence with the isotope resolved Xe ion formed in the same event. This allowed the photoelectron angular distributions of the nuclear spin (I) zero atoms to be separated from the non-zero I atoms. This has the important consequence that the effects of nuclear spin depolarization of the intermediate state due to precession of the electronic angular momentum about the total angular momentum vector can be eliminated. This allows the pure electronic dynamics of the photoionization to be isolated.
The manuscript prepared during the STSM was recently published in Physical Review Letters:
Isotopically Resolved Photoelectron Imaging Unravels Complex Atomic Autoionization Dynamics by Two-Color Resonant Ionization, P. O’Keeffe, E.V. Gryzlova, D. Cubaynes, G.A. Garcia, L. Nahon, A.N. Grum-Grzhimailo, and M. Meyer, Physical Review Letters, 111, 243002 (2013).
Figure: The raw photoelectron images for parallel linear polarizations of both SR and optical laser light of the photoelectrons taken in coincidence with the non-zero and zero nuclear spin isotopes of Xe. The images are shown as 3D representations in order to visualize clearly the effect of the nuclear spin on the photoelectron angular distribution. Copyright: American Physical Society.
Radiation damage in nano-hydrated biomolecular systems:
direct and indirect processes and radiosensitizer efficiency
A one-year postdoctoral position is available in the field of atomic and molecular physics in the group AMA (Atoms, Molecules and Clusters) of the Centre de Recherche sur les Ions, les Matériaux et la Photonique (CIMAP), in Caen (France). The position is funded by the “Plan Physique Cancer” (INCa/INSERM) in the framework of a collaboration between the CIAMP and the Institut de Physique Nucléaire de Lyon (IPNL).
Research project: Nowadays, ion beam cancer therapy is a powerful emergent technique used in cancer treatment, especially for deep-seated tumors. The advantages of ion beams with respect to conventional radiotherapy techniques based on photons and electrons are well known. They are due to the characteristic Bragg peak, the small lateral spreading and the increased relative radiobiological efficiency. However, a number of important scientific questions, especially related to DNA damage assessment at the molecular level, have not been resolved. We propose to study the fundamental processes occurring at the molecular level during the interaction of ions with small biological systems in the gas phase. We will measure the destruction rates of biomolecules governed by energy and charge transfer. Mass spectrometric analysis will be applied to obtain detailed insights into the fragmentation pathways of ion-induced radiation damage and the secondary electron production. The studies will be performed with isolated as well as nano-hydrated biomolecules to clarify the role of water molecules in the radiation damage process (direct and indirect effects). In addition, noble metal nanoparticles will be included in the target in order to elucidate their enhancing effect on the radio-biological efficiency of ion irradiation. To improve our understanding of the first steps of radiation damage induced by ionizing radiation, the experimental work will be supported by simulations of radical production by water radiolysis with and without nanoparticle included.
The candidate will further develop the experimental set-up and implement first experiments on ion collisions with biological complex systems in the gas phase. The candidate should have a PhD in Physics or Physical-Chemistry. Preference will be given to candidates with experience in instrument development, gas phase techniques and mass spectrometry. The successful candidate is expected to start in January 2014. The monthly gross salary is 2900 euros. Applicants should send a letter of motivation, CV, publication list and two letters of recommendation from academic referees to:
Boulevard Henri Becquerel, BP 5133
F-14070 Caen cedex 5
+33(0)2 31 45 49 91
Project title: Ultrafast dynamics and spectroscopy of DNA/RNA nucleobases and analogues
A postdoctoral position is available in the area of ab initio molecular dynamics in the group of Prof. Leticia González at the Institute of Theoretical Chemistry, Faculty of Chemistry of the University of Vienna. The position is funded by the FWF for up to two years.
Research topic: The aim of the project will be to develop a method to calculate time-dependent ionization yields in a surface-hopping method, so that the results of on-the-fly non-adiabatic ab initio molecular dynamics can be directly compared with time-resolved photoelectron experiments. Simulations will be performed on DNA/RNA nucleobases and analogues prompted to display high triplet yields. The calculations will be done using a recently developed molecular dynamics code that allows treating non-adiabatic and spin-orbit couplings simultaneously. More about our research can be found in www.theochem.univie.ac.at
Qualifications: Qualified candidates hold (or are in the process of obtaining) a PhD in Chemistry or Physics, have strong programming skills and experience with ab initio molecular dynamics techniques. Knowledge of multiconfigurational quantum chemistry is desirable. Successful candidates are highly motivated, have excellent communications skills and are able to work independently as well as a part of a team. Excellent English command, written and spoken.
Interested individuals should submit a PDF containing motivation letter, CV, publication record and the contact information of three potential referees to:
Prof. Dr. Leticia González
University of Vienna
Institute of Theoretical Chemistry, Währinger Str. 17, A-1090 Vienna, Austria
The first general meeting of the XLIC Cost Action will be held in Madrid (Spain) from 11 until 13 November.
On these dates we will also have the Management Committee Meeting and the Kick Off Meeting of the Working Groups.
Click here to register (DEADLINE 15th October, 2013)
Application for Short Term Scientific Missions -STSM- is already open.
STSM is one of the main mechanism we want to promote in the Action to the exchange of expertise among groups. Application to do STSM during the summer 2013 are most welcome. STSM can last between 1 week and 3 months and you can apply for them at any time. The time to approve a STSM should be ideally shorter than 2 weeks.
Please go to the section STSM to get the information on how to apply.