Flash-freezing of molecular ions in a storage ring
Rapid rotational cooling of molecular ions by interaction with electrons has been observed for the first time in the TSR heavy ion storage ring of the Max Planck Institute for Nuclear Physics in Heidelberg.
This kind of laboratory astrophysics helps to understand in more detail the physical and chemical properties of cold interstellar matter.
The interaction of molecular ions with free electrons is of key importance to understand the physical and chemical properties of cold astrophysical environments like interstellar molecular clouds. Whereas electron-ion recombination has been studied in great detail in storage ring and ion trap experiments in the last two decades, information about the exchange of energy between slow electrons and the internal motion (rotation and vibration) of molecular ions was rather limited.
Researchers of the Max Planck Institute for Nuclear Physics (MPIK) in Heidelberg, of the Weizmann Institute of Science in Rehovot (Israel) and of three other collaborating institutions have now published first quantitative results for fast electron cooling of rotating singly charged HD molecular ions. In the TSR heavy ion storage ring of the MPIK an HD molecular ion beam was merged with cold electrons of 33 K (-240°C) temperature, i. e. 33 degrees above absolute zero.
The interaction with the electrons reduced the rotational temperature of the ions from initially about 1200°C to -150°C within only 8 seconds and stabilized it at this low value in the simultaneously acting thermal radiation field at the ambient room temperature (300 K). During the process, the ions pass the electron cooling bath about 175000 times per second. The cooling due to so-called superelastic collisions, where some amount of energy is transferred from the rotational motion of the ion to linear motion of the electron, is well described by theoretical calculations initiated through this experiment.
Prof. Dr. Andreas Wolf
Max Planck Institute for Nuclear Physics, Heidelberg
Prof. Dr. Daniel Zajfman
Weizmann Institute of Science, Rehovot, Israel
http://link.aps.org/doi/10.1103/PhysRevLett.102.223202 Orginal publication
http://www.mpi-hd.mpg.de/blaum/members/molecular-qd/index.en.html Group of Prof. Andreas Wolf
http://www.weizmann.ac.il/particle/molecule/ Group of Prof. Daniel Zajfman
Dr. Bernold Feuerstein | Max-Planck-Institut
The most recent press releases about innovation >>>
Die letzten 5 Focus-News des innovations-reports im Überblick:
An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.
Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...
Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.
Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...
Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.
As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...
Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.
With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...
Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine
Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...