Early-stage researcher position opening
The Experimental particle physics department (F9)
at the Jožef Stefan Institute
, Ljubljana, Slovenia is looking for a young experimental physicist, ready to participate in our research activities as an early-stage researcher (3.5-year research position). The research work will lead to the award of a PhD.
The early stage researcher work will be focused on novel photon detectors for positron emission (PET) tomography. The research is closely linked to the other main activity of the lab, studies of an aerogel RICH
, an upgrade of the particle identification system in the forward direction of the BELLE
The early stage researcher is expected to work on all main topics of the project, from the detector R+D to simulation of the detector response and optimisation of the counter parameters. He/she is expected to have some hardware experience.
The candidate should have a undergraduate degree in physics or electrical engineering. He/she should mail the curriculum vitae and the names and email addresses of two referees (or arrange for two letters of reference).
The position is open until filled.
A brief description of the research topic
Positron emission tomography (PET) is a non-invasive method for in-depth and in-vivo imaging of live tissue, which allows to track the interesting physiological metabolism of bio-molecules, which have been marked with a radioactive, positron emitting isotope. The substance distribution in tissue is determined by detecting pairs of the annihilation gamma rays, detected with position sensitive detectors. The points of detection determine a straight line passing close to the nucleus, which emitted the positron. By detecting a large number of such gamma ray pairs and determining the corresponding straight lines, it is possible to reconstruct the three dimensional distribution of sources in the tissue.
The majority of PET devices use photo-multipliers as detectors of scintillation photons. Due to their size and relatively poor ratio of active to total surface, an alternative detector without these deficiencies would provide significantly better image contrast. The need to unify different image modalities in one measurement is increasing, e.g. one would like to incorporate a PET apparatus inside a MRI magnet for simultaneous imaging of tissue function and density.In this case, the photo sensors should be insensitive to high magnetic fields.
An additional improvement of the method is the measurement of time-of-flight, which in the larger clinical devices reduces significantly the field of view used in the reconstruction and thereby improves the image contrast.
In the last years a great progress in the PET development has been made by a semi conductor detector, silicon photomultiplier (SiPM), working in the Geiger mode. We have already showed that the single SiPMs in combination with the LYSO scintillator have sufficient energy resolution and proved their insensitivity to magnetic fields. However, for usable PET method it is on one side necessary to know the operation of the larger system and on the other side to measure the interaction time accurately.
The early stage resesarcher will be involved in the development of a prototype system to explore possible advances in PET by using silicon photomultipliers.
For further details please contact:
|| Ljubljana, Slovenia
| Salary (gross)
|| about 1200€/month
|| 42 months, start in October 2010
|| Slovene or English
J. Stefan Institute, Jamova 39, SI-1000 Ljubljana, Slovenia