IEEE prize awarded to CERN PhD student

Rafael Ballabriga Suñe is the recipient of the 2006 Institute of Electrical and Electronics Engineers, Inc. (IEEE) Nuclear and Plasma Sciences Society (NPSS)'s Student Paper Award. Ballabriga's winning paper reported on a prototype chip, which belongs to a new generation of single photon counting hybrid pixel detector readout chips - Medipix3. The NPSS established this award in 2005 to encourage outstanding student contributions and greater student participation as principle or sole authors of papers. The prizes were presented at the IEEE Nuclear Science Symposium held in San Diego on 29 October to 4 November.

The prototype chip was designed by Ballabriga based on ideas generated within the CERN Medipix team - part of the PH Microelectronics group. It could be used in various fields in the future, including medical imaging, neutron imaging, electron microscopy, radiation monitoring and other applications in high-energy physics. The novel aspect of the pixel readout architecture is that when a photon strikes a region of the silicon sensor creating a charge that is shared between two or more pixels, the neighbouring pixels 'talk' to each other adding up their charges to reconstruct the amplitude of the original charge cloud and allocate the hit to only one pixel. This allows improved spectroscopy while maintaining the high spatial resolution of the image. An additional feature of the Medipix3 is the ability to take images continuously.