Research

 

 

 1. Our research is in the field of Cosmochemistry.

 
  2. Our primary method is mass spectrometry. Using this technique we determine abundances and isotopic
    compositions, primarily of the noble gases (helium, neon, argon, krypton and xenon).		  

 

3. A main line of research deals with presolar grains ("stardust"). Small amounts of these grains occur in the matrix of
   the most primitive meteorites. We extract them by combinations of chemical and physical separation methods.

 
  4. Another focus of our research is the study of noble gases in meteorites from planet Mars.  

 

5. The study of the noble gases provides also information about the cosmic ray exposure age of the meteorites, which
    is the time span between ejection from their parent body (an asteroid in most cases) and their arrival on Earth.

 
     

 

Information:

 

 

- Some recent results

 

 

- List of publications

 

 

- popular article in Max-Planck-Research

 
  - popular article in Sterne und Weltraum (in German)  
     

 

Some recent and ongoing projects and collaborations:

 

 

- improving extraction methods for the acid-resistant presolar grains

 

 

- mass spectrometric investigations of trace elements in presolar nano-diamonds with the aims of a) deciphering the
  origin of these grains; and b) contributing to the understanding of processes of nucleosynthesis in supernovae;
  partly in collaboration with University of Vienna and ETH Zürich (Eurogenesis project)

 

 

- simulating trapping of trace elements by pre-solar nano-diamonds by studying ion implantation of rare gases into
   terrestrial explosively synthesized nano-diamonds;
   collaboration with Karpov Institute of Physical Chemistry (Moscow) and University of Hawaii

 

 

- search for isotope abundance anomalies (in Se, e.g.) during stepwise dissolution of primitive meteorites as a tool in
    the search for acid-resistant pre-solar grains

 
  - r-process nucleosynthesis; model calculations in the HEW scenario for explaining solar system abundances as well as
   isotope abundance anomalies		  

 

- abundance and isotopic composition of noble gases in bulk and mineral separates from Martian meteorites

 
  - noble gases in howardites (meteorites probably from asteroid Vesta); an aim - also with respect to NASA's mission
   DAWN to Vesta - is the evaluation of other indicators for the presence of truly regolithic material (at the surface,
   exposed to the solar wind); project in collaboration with NASA Johnson Space Center		  
  - age of presolar (stardust) silicon carbide grains;
   collaboration with ETH Zürich and Washington University, St. Louis		  
  - investigation of possible pre-irradiation of chondrules (~mm-sized melt globules that gave the chondrite meteorites
   their name) in the early solar system; collaboration with University of Heidelberg
   supported by DFG in the framework of priority program SPP 1385 "The first 10 million years..." 		 
  - noble gases in Antarctic micrometeorites;
   supported by DFG in the framework of priority program SPP 1385 "The first 10 million years..." 		 

 

- determination of landscape evolution (surface exposure, erosion rate) in Antarctica, by means of the abundance
   of cosmogenic neon;
   collaboration with Bundesanstalt für Geowissenschaften und Rohstoffe (BGR; Hannover) and FZ Dresden-Rossendorf

 

 

 

 

 

Information:

 

 

- Some recent results

 

 

- List of publications