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The department of physics and astronomy offers information to and cooperation with the society in various ways, such as organizing exhibitions and demonstrations to schools and the general public, taking part in various working groups within our respective fields of research and by performing commissioned research and education (see links to the left).

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Current seminars

Superstring effective actions and brane-anti brane systems

Speaker: 
Ehsan Hatefi
Department: 
ICTP (Trieste, Italy)
Time: 
2014-09-04 13:15 - 14:15
Location: 
Oseenska rummet 73121
Type : 
Theoretical Physics

In this talk , we consider all kinds of effective actions involving DBI, Chern-Simons and new Wess Zumino actions. Our aim is to provide a comprehensive explanation even for D- brane-anti D-brane systems.We then introduce various new techniques to derive allorder alpha' corrections to type II effective actions. The new actions effective actions /couplings are neither inside Myers‘ terms nor within pull-back/Taylor expansions.

What are Little Worlds Made Of? Stellar Abundances and Planet Composition

Speaker: 
Eric Gaidos
Department: 
Department of Geology and Geophysics, University of Hawai'i, USA
Time: 
2014-09-04 15:15 - 16:15
Location: 
Hjorter's room (Å73101)
Type : 
Astronomy and Space Physics

The NASA Kepler survey has identified numerous Earth-size planets transiting other stars, and limited Doppler radial velocity measurements hint that many of these are primarily made of heavy, refractory elements, i.e. are "rocky". However, we have no direct measurements of the composition of these planets. The photospheres of Sun-like stars offer indirect information because the stars and protoplanetary disks have a common origin, and material accreted from a disk can change the abundances in the relatively thin convection zones of these stars. A strong correlation between giant planet occurrence and stellar metallicity has proved robust to scrutiny, but the underlying mechanism is unclear.

Presentation on the Neutron Resonance Analysis School 2011

Speaker: 
Erwin Alhassan
Department: 
Department of Physics and Astronomy
Time: 
2014-09-05 13:15
Location: 
73121 (Oseenska rummet)
Type : 
Applied Nuclear Physics

The presentation is given as part of the Neutron Resonance Analysis School I attended in 2011. I will present the general evaluation process; describe the resonance parameters and how they are represented in the ENDF format. Also, a brief description of the general theoretical models used in the analysis of neutron resonance data - R-matrix theory (the single-level Breit-Wigner, the multi-level Breit Wigner and Reich Moore approximation) for the resolve region and the Hauser-Feshbach theory for the unresolved resonance region will be covered. Finally, the Doppler broadening of the single level Breit-Wigner formalism for resonance absorption will be presented.