After six very successful years of OKC leadership, Lars Bergström was asked to become the new Dean of the Mathematics and Physics Section of the Science Faculty of Stockholm University. As a consequence, he has stepped down as OKC director and a new position at the Department of Physics at Stockholm University has been announced to find a replacement. In the mean time, I will serve as director of the centre. It is with a sense of great pride – and a fair bit of apprehension – that I take on this challenge: it is no small task to keep up the high standards set by Lars!
Since its birth in 2008, the Oskar Klein Centre has become a national and international flagship in the field. OKC scientists have featured very prominently every year in the December summary of Populär Astronomi over the most cited papers in Astronomy with a first author currently working in Sweden. 2014 was not an exception, half of the top-ten papers were lead by OKC members. This is in fact, a low estimate, since some of the highly cited OKC-lead publications are by Fermi and IceCube collaborations, which uses alphabetical author lists. Best cited among the listed papers was Katie Freese’s March arXiv submission exploring the consistency between her model of Natural Inflation and the claimed results from BICEP2 on primordial gravitational waves.
We are extremely pleased to have Katie with us since last fall, as she shares her time between a position at the Physics Department and as the new director of Nordita. Sadly for cosmology and fundamental physics, disentangling the tiny first Big Bang traces from the signatures of more mundane astrophysical foregrounds may be more challenging than originally thought by the BICEP2 team. This is one of the big issues to be addressed during 2015, the year marking the 100:th anniversary of Einstein’s conception of General Relativity.
Other highlighted OKC results include two studies [Goobar et al; Amanullah et al] of supernova SN2014J, the closest Type Ia supernova in many decades. These are the kind of stellar explosions used as standard candles to study the accelerated expansion of the Universe. Understanding the nature of this phenomenon, dubbed ”dark energy”, remains a great challenge for fundamental physics, as does the ”dark matter” responsible for the observed structures.
Dark matter particles are searched for by OKC members using the Fermi gamma-ray satellite and the IceCube neutrino detector. IceCube also recently presented new evidence for high-energy neutrinos of astrophysical origin.
The paper lead by OKC’s Stephan Rosswog at the Department of Astronomy on the outcome of merger of the most compact objects in nature also made it to the top ranked research articles of 2014. Congratulations to all the successful researchers at the centre!
We look forward to many great scientific breakthroughs by OKC members in the New Year. The exploration of the extremes of nature continues, both in the skies and at the LHC accelerator at CERN. From this new platform, I will keep you posted of our progress!
– Ariel Goobar