FIAS Scientific Report 2011 - Frankfurt Institute for Advanced Studies ...

at risk of developing autism or other diseases.
The research group of Danko Nikolić has discovered that spike timing of neurons in visual cortex can change
with high precision. A small change in stimulus properties can determine whether neuron A fires a few
milliseconds before neuron B, or the other way around, B firing before A. Nikolić and collaborators propose
that these relationships in spike timing have strong influence on the flow of information throughout the
cortex.
Life Science and Chemistry
The Meso-Bio-Nano group at FIAS (A. Solov’yov) studies the structure and properties of a variety of objects
on the nanoscale, e.g., atomic and molecular clusters, nanoparticles, nanowires, micro-droplets, and
biomolecules.
Recently significant progress has been achieved in the quantitative molecular level understanding of the cascade
of processes and mechanisms responsible for damaging of biological targets by heavy-ion irradiation.
These studies extend significantly our knowledge about the physical mechanisms and molecular processes
involved in ion-beam cancer therapy, and radiation damage in general. The MBN Science team at FIAS
coordinates the EU funded COST Action Nano-IBCT (Nanoscale insights into ion beam cancer therapy) in
which teams from 20 EU countries, Australia, Canada, USA, and Japan are involved.
A new patent for the invention of a scheme for the construction of a novel source of coherent monochromatic
radiation operating in the range of high-frequency gamma rays (i.e. a gamma laser) has been granted (W.
Greiner, A.V. Korol, A. Kostyuk, A.V. Solov’yov). The key element of the suggested gamma laser device is
a periodically bent crystal through which energetic, ultrarelativistic and modulated charged particles (electrons
or positrons) propagate in the channelling regime. The suggested scheme has similarities with the
scheme of the so-called Free Electron Laser (FEL). Such lasers have been recently constructed in several
countries including Germany and operate in X-ray frequency range. In the suggested gamma laser scheme
the heavy and large magnets used in FEL are substituted with compact periodically bent crystals. This allows
to reduce drastically the wavelength of electron/positron periodic motion and thus increase significantly the
energy of the emitted photons.
Computer Science
The ALICE high level trigger was operated at CERN the entire year. It was used to analyze the entire event
data stream of more than 20 GB/s in real time. In this process the on-line data was compressed by more
than a factor 4. The ALICE HLT is the only system at CERN, which operates graphic cards as hardware
accelerators. The entire tracking of the experiment is performed on less than 50 computers with 50 GPUs.
A new algorithm was developed, allowing the highly efficient computation over Galois fields, which is
required for redundant data coding. With the increasing data sizes in particular at CERN and at GSI such
redundant coding is essential as no hardware can be reliable enough.
A new software package was developed, allowing highly efficient vectorized programming. Without such
programming modern processors are used by less than 25% of their capabilities. This package is already in
use at various sites and is planned to be incorporated into the ROOT package, which is used by physicists
around the world.
A matrix multiplication and Linpack software package was developed, which outperforms all other existing
solutions, in particular on ATI GPGPUS, which are used at the LOEWE-CSC. This software enabled the
LOEWE-CSC to reach its high performance rating.
In cooperation with the physics groups a first version of a Lattice QCD program was developed to run on
GPUs, which is highly efficient. In addition a new version of the Frankfurt UrQMD model was developed,
which is also running on GPUs. The realized speed-up is a factor of 160.
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