5 October 2010

Christopher Pethick receives the prestigious Hans Bethe Prize

Professor at the Niels Bohr Institute, Christopher Pethick, has been awarded the prestigious American Hans A. Bethe Prize, awarded by the American Physical Society in recognition of outstanding research in the field of physics. Chris Pethick is receiving the prize "for his fundamental contributions to the understanding of nuclear matter at very high density, the structure of neutron stars, their cooling and the related neutrino processes and astrophysical phenomena".

Christopher Pethick received the news of the award at a reception at the Niels Bohr Institute with a typically warm remark: "I have the good fortune to be allowed to work at an institute where you get peace and quiet to research". Christopher Pethick is English and began his career at the University of Oxford, where he received his D. Phil degree in physics in 1966. He then went to Illinois in the United States and in 1973 he became a professor at Nordita in Copenhagen and is now affiliated with the Niels Bohr International Academy at the Niels Bohr Institute.

Chris Pethick’s research spans from the inner universe of atoms to neutron stars out in the Universe.  He works with ultra-cold gasses, which are cooled down to a millionth of a degree above absolute zero at minus 272 degrees Celsius and studies how particles in the atomic nucleus behave on a microscopic level. The description of nuclear matter contributes to the understanding of neutron stars in the universe. 

"A neutron star is like an enormous atomic nucleus and many of its properties can be explained by what we learn in the lab", explains Chris Pethick. A neutron star is a massive star that has collapsed into a very compact core. The particles are compressed together so much that the electrons cancel out the protons’ charge so that they become neutrons.  The gap between the atomic nucleus and the electrons disappears and only the compact core remains.

"The calculations show that just before the nuclei are pressed together they are not in the shaped like spheres, but rather strings or sheets, and the mass becomes a dense liquid", explains Chris Pethick and says, that what he finds interesting is the complex phase that the star undergoes when it collapses and becomes a dense mass. 

He will be awarded the Hans A. Bethe Prize at a ceremony at the American Physical Society in April 2011.

Hans A. Bethe Prize >>