The OKC Day

This spring’s Oskar Klein Centre day took place in beautiful surroundings yesterday (Monday, May 30th), at Villa Källhagen – a nice conference centre in Djurgården near the water. As is now customary in these general OKC meetings, first a summary of the activities of the working groups was done, with slide presentations by Jonas Enander (Dark Energy), Christoph Clement (Dark Energy), Elena Moretti and Josefin Larsson (Extreme Objects) and Rachel Rosen (Fundamental Theory). Although the working group for Structure formation was left without slides due to a late cancellation, Lucia Gaita and Kanan Datta made a very good, unprepared presentation of their activities.

New instruments for Dark Matter

Things have been happening lately with experiments which could eventually shed some light on dark matter.

The IceCube Neutrino Observatory, which was completed last December, defiantly started data taking in its final configuration on Friday the 13:th of this month. Data from 5397 optical modules are recorded at a rate of 2370 events per second, and about 50 million events per day are sent North for analysis via satellite (unfortunately,
almost all are due to atmospheric muons, not neutrinos).

Interview with Constanze Jahn: a PhD student visiting OKC

Costanze is a PhD student visiting the Oskar Klein Centre for a couple of months. I asked her to tell us a bit more about this experience.
where are you from? What brings you to Stockholm?
In Germany I am working at the ECAP, the Erlangen Centre for Astroparticle Physics, which is part of the university of Erlangen. There I started my PhD in the H.E.S.S. Collaboration in 2009.

The Fermi symposium 2011: AGNs, pulsars and gamma ray bursts

The results presented at the III Fermi symposium in Rome reflected, in particular, what a magnificent instrument the Fermi LAT is for observing active galactic nuclei and pulsars. The 2 source catalogue 2FGL was presented and will soon be released with 1888 sources. Much attention was given to the blazar 3C454.3 which has been monitored since the launch and has undergone a series of very bright outbursts.

Observing supernovae with the Gran Telescopio Canarias

We are just about to finish our second night at the world’s largest optical telescope, the 10.4m Gran Telescopio Canarias (GTC) on the summit of the island of La Palma. For me personally, observing surely confirms that the only difference between children and scientists are the prices of their toys. The pricetag of the GTC is roughly 650000 times more than the telescope I got in the 8th grade, but on the other hand it also has about 10000 times light collecting capability.

Dissipative photospheres in gamma-ray bursts

One of the many research topics at OKC is the study of gamma-ray bursts (GRBs). Several aspects of them are studied, such as the gamma-ray and X-ray emission, the afterglow emission, and the interaction between the bursts and the circumburst medium.

In a recent paper based on observations with the Fermi Gamma-ray Space Telescope it is argued that the main emission during the first few minutes of GRBs is dominated by the jet photosphere and that there is significant amount of energy dissipation close to the photosphere. This result is significant for our understanding of physics of GRB jets.


Brainstorming is one of the most known and diffused creativity boosting techniques used for getting fresh ideas. While brainstorming can also be done by individuals, it is most effective when done in a group of 10-12 people.
The technique is in principle very simple. A topic of discussion should be clarified and well defined at the beginning of a brainstorming session, possibly in terms of a question to answer. The definition of the task is important and one of the key of a successful brainstorming session.

Cosmology, astrophysics, astroparticle physics