לוח שנה משולב

The study of molecular collisions with the highest possible detail has been an important research theme in physical chemistry for decades. Over the last years we have developed methods to get improved control over molecules in a molecular beam [1]. With the Stark decelerator, a part of a molecular beam can be selected to produce bunches of molecules with a computer-controlled velocity and with longitudinal temperatures as low as a few mK. The molecular packets that emerge from the decelerator have small spatial and angular spreads, and have almost perfect quantum state purity. These tamed molecular beams allow for crossed beam scattering experiments with unprecedented levels of precision and sensitivity [2,3].

I will discuss our most recent results on the combination of Stark deceleration and velocity map imaging. The narrow velocity spread of Stark-decelerated beams results in scattering images with an unprecedented sharpness and angular resolution. This has facilitated the observation of diffraction oscillations in the state-to-state differential cross sections for collisions of NO with rare gas atoms [4]. Observed features in the diffraction pattern result from subtle quantum interference effects, and appear extremely sensitive to the potential energy surfaces governing the scattering process [5].

[1] S.Y.T. van de Meerakker, H.L. Bethlem, G. Meijer, Nature Physics 4, 595 (2008).
[2] J.J. Gilijamse, S. Hoekstra, S.Y.T. van de Meerakker, G.C. Groenenboom, G. Meijer,
Science 313, 1617 (2006).
[3] M. Kirste, X. Wang, H.C. Schewe, G. Meijer, K. Liu, A. van der Avoird, L.M.C.
Janssen, K.B. Gubbels, G.C. Groenenboom, S.Y.T. van de Meerakker,
Science 338, 1060 (2012).
[4] A. von Zastrow, J. Onvlee, S.N. Vogels, G.C. Groenenboom, A. van der Avoird,
S.Y.T. van de Meerakker, Nature Chemistry 6, 216 (2014).
[5] S.N. Vogels, J. Onvlee, A. von Zastrow, G.C. Groenenboom, A. van der Avoird,
S.Y.T. van de Meerakker, Phys. Rev. Lett. 113, 263202 (2014).

In the last decade advances in Next Generation Sequencing and bioinformatics enabled the unraveling of global RNA modifications and editing. The evolving field of epitranscriptomics proved to be important in cell fate decisions, normal development and disease.
The lecture will deal with A to I editing-based mechanisms relevant to cancer and with the emerging role
of m6A methylation in the precise regulation of early embryonic development.

Several ways to search for time-reversal-violation in beta decay of trapped nuclei will be reviewed. The newly upgraded TRINAT trap system will be described showing the high sensitivity required for such a search. The experimental plans for such experiments will be described.

Photoionization models calculate the energy transfer from the
ionizing radiation to the gas. The associated momentum transfer
is not always included. This radiation pressure will set the density
structure within the photoionized gas, in particular if the gas is
not radially accelerating. I will present the results of such
calculations for photoionized gas in Active Galactic Nuclei, which
provide a simple explanation for a range of properties observed.