Joint Nuclear Astrophysics Seminar

Europe/Berlin
Almudena Arcones (TU Darmstadt / GSI) , Camilla Juul Hansen (University of Heidelberg, ZAH) , Iris Dillmann (Justus Liebig Universität/ GSI Darmstadt)
Description
Nuclear astrophysics is an interdisciplinary field and this makes it so fascinating, but also renders the communications between different fields. We would like to introduce a seminar series with the goal of sharing knowledge and vocabulary among nuclear physicists, astrophysicists, and observers in an open atmosphere full of discussions and questions.
A dedicated interdisciplinary seminar on these topics does not exist in the Darmstadt-Frankfurt-Mainz-Giessen-Heidelberg region. However, we are aware about the large number of seminars and colloquia around, therefore this nuclear astrophysics seminar will take place only once per month and be advertised broadly.
Since some of the people would have to travel we will have two talks  (starting at 16:30) with the possibility of going for dinner together and continue the discussions.
The seminar takes place at the TU Darmstadt in the Theory Center of the Institut für Kernphysik:
Schlossgartenstr. 2, S2|11, Room 11 (ground floor).
A map can be found here.

Previous JoNAS: Heidelberg, May 6, 2013 Giessen, January 24,2013 Heidelberg, December 13, 2012 Darmstadt, November 22, 2012
    • 16:30 17:30
      Proton capture reactions in thermonuclear supernovae and the p process: <br />Kerstin Sonnabend (Institut für Angewandte Physik, Goethe-Universität Frankfurt) S2|11 Room 11 (TU Darmstadt (IKP, Theory Center))

      S2|11 Room 11

      TU Darmstadt (IKP, Theory Center)

      There are about 35 proton-rich nuclei whose production cannot be explained by neutron capture processes. The synthesis of these so-called p nuclei is thought to be realized in different astrophysical scenarios which are usually referred to as sites of p-process nucleosynthesis. These scenarios will be briefly introduced including the different approaches to determine the nuclear physics needed for their modelling. As a highlight, the production of the lightest p nuclei via proton capture reactions in thermonuclear supernovae will be presented. Two recent publications [1,2] found a significant contribution to the production of the most abundant p nucleus 92-Mo by this mechanism. Experimental approaches for the determination of the required reaction rates will be explained and first results will be shown.
      [1] C. Travaglio et al., The Astrophysical Journal 739 (2011) 93
      [2] M. Kusakabe et al., The Astrophysical Journal 726 (2011) 25

    • 17:30 18:30
      Linking stellar observations to nuclear physics: <br />Camilla Juul Hansen (Landessternwarte, Heidelberg University) S2|11 Room 11 (TU Darmstadt (IKP, Theory Center))

      S2|11 Room 11

      TU Darmstadt (IKP, Theory Center)

      Stellar spectra carry a wealth of information, and depending on their resolution we can extract e.g. the stellar ages, chemical composition, radial velocities, as well as the stellar parameters. By observing a large sample of different stars with high-resolution spectrographs, we can investigate the chemical evolution, of all elements detectable, from lithium to uranium. Furthermore, knowing the complete abundance pattern of the star enables a comparison with model predictions, which in turn will provide information on the formation site and process of the detected elements.
      In this way stellar abundances are chemical tracers. Hence, they can guide our understanding of nuclear processes, and thereby link nuclear physics (e.g. reaction rates), through astrophysics theory (such as yield predictions) to astronomy (chemical evolution and stellar abundances).

      In this talk I will outline how stellar abundances are derived and used in a chemical evolution scheme. The main focus is on the heavy elements (Sr, Y, Zr, Mo, Pd, Ag, Ba, Nd, and Eu), and how these can be used as tracers of their formation processes.

    • 19:00 21:30
      Dinner