@article{ZiemonsBerghoffLanskeetal.1988, author = {Ziemons, Karl and Berghoff, G. and Lanske, D. and Schultze, K.}, title = {Strangeness production in deep inelastic muon-nucleon scattering}, series = {Verhandlungen der Deutschen Physikalischen Gesellschaft}, volume = {23}, journal = {Verhandlungen der Deutschen Physikalischen Gesellschaft}, number = {5}, isbn = {0420-0195}, pages = {T309 -- T309}, year = {1988}, language = {en} } @article{StreunBrandenburgBroekeletal.2004, author = {Streun, M. and Brandenburg, G. and Br{\"o}kel, M. and Fuss, L. and Larue, H. and Parl, C. and Zimmermann, E. and Ziemons, Karl and Halling, H.}, title = {The ClearPET data acquisition}, series = {2003 IEEE Nuclear Science Symposium Conference Record, Vol. 5}, journal = {2003 IEEE Nuclear Science Symposium Conference Record, Vol. 5}, issn = {1082-3654}, pages = {3097 -- 3100}, year = {2004}, abstract = {Within the Crystal Clear Collaboration a modular system for a small animal PET scanner (ClearPET™) has been developed. The modularity allows the assembly of scanners of different sizes and characteristics in order to fit the specific needs of the individual member institutions. Now a first demonstrator is being completed in Julich. The system performs depth of interaction detection by using a phoswich arrangement combining LSO and LuYAP scintillators which are coupled to multi-channel photomultipliers (PMTs). A free-running ADC digitizes the signal from the PMT and the complete scintillation pulses are sampled by an FPGA and sent with 20 MB/S to a PC for preprocessing. The pulse provides information about the gamma energy and the scintillator material which identifies the interaction layer. Furthermore, the exact pulse starting time is obtained from the sampled data. This is important as no hardware coincidence detection is implemented. All single events are recorded and coincidences are identified by software. An advantage of that is that the coincidence window and the dimensions of the field of view can be adjusted easily. The ClearPET™ demonstrator is equipped with 10240 crystals on 80 PMTs. This paper presents an overview of the data acquisition system.}, language = {en} } @article{AuffrayBruyndonckxDevroedeetal.2004, author = {Auffray, E. and Bruyndonckx, P. and Devroede, O. and Fedorov, A. and Ziemons, Karl}, title = {The ClearPET project}, series = {Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment}, volume = {527}, journal = {Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment}, number = {1-2}, isbn = {0168-9002}, pages = {171 -- 174}, year = {2004}, abstract = {The Crystal Clear Collaboration has designed and is building a high-resolution small animal PET scanner. The design is based on the use of the Hamamatsu R7600-M64 multi-anode photomultiplier tube and a LSO/LuYAP phoswich matrix with one to one coupling between the crystals and the photo-detector. The complete system will have 80 PM tubes in four rings with an inner diameter of 137 mm and an axial field of view of 110 mm. The PM pulses are digitized by free-running ADCs and digital data processing determines the gamma energy, the phoswich layer and even the pulse arrival time. Single gamma interactions are recorded and coincidences are found by software. The gantry allows rotation of the detector modules around the field of view. Simulations, and measurements a 2×4 module test set-up predict a spatial resolution of 1.5 mm in the centre of the field of view and a sensitivity of 5.9\% for a point source in the centre of the field of view.}, language = {en} } @article{ZiemonsAuffrayBarbieretal.2004, author = {Ziemons, Karl and Auffray, E. and Barbier, R. and Brandenburg, G.}, title = {The ClearPET TM LSO/LuYAP phoswich scanner: a high performance small animal PET system}, series = {2003 IEEE Nuclear Science Symposium Conference Record, Vol. 3}, journal = {2003 IEEE Nuclear Science Symposium Conference Record, Vol. 3}, issn = {1082-3654}, pages = {1728 -- 1732}, year = {2004}, abstract = {A 2nd generation high performance small animal PET scanner, called ClearPET™, has been designed and a first prototype is built by working groups of the Crystal Clear Collaboration (CCC). In order to achieve high sensitivity and maintain good uniform spatial resolution over the field of view in high resolution PET systems, it is necessary to extract the depth of interaction (DOI) information and correct for spatial degradation. The design of the first ClearPET™ Demonstrator based on the use of the multi-anode photomultiplier tube (Hamamatsu R7600-M64) and a LSO/LuYAP phoswich matrix. The two crystal layers of 8*8 crystals (2*2*10 mm3) are stacked on each other and mounted without light guide as one to one on the PMT. A unit of four PMTs arranged in-line represents one of 20 sectors of the ring design. The opening diameter of the crystal ring is 137 mm, the axial detector length is 110 mm. The PMT pulses are digitized by free-running ADCs and digital data processing determines the gamma energy, the phoswich layer and even the pulse arrival time. Single gamma interactions are recorded and coincidences are found by software. The gantry allows rotation of the detector modules around the field of view. The measurements have been done using the first LSO/LuYAP detector cassettes.}, language = {en} } @article{ZiemonsAchtenAuffrayetal.2004, author = {Ziemons, Karl and Achten, R. and Auffray, E. and M{\"u}ller-Veggian, Mattea}, title = {The ClearPET™ neuro scanner: a dedicated LSO/LuYAP phoswich small animal PET scanner}, series = {2004 IEEE Nuclear Science Symposium conference record : Nuclear Science Symposium, Medical Imaging Conference ; 16 - 22 October 2004, Rome, Italy ; [including the Symposium on Nuclear Power System (SNPS), 14th Room Temperature Semiconductor X- and Gamma-Ray Detectors Workshop and special focus workshops] / NPSS, Nuclear \& Plasma Sciences Society. Guest ed.: J. Anthony Seibert}, journal = {2004 IEEE Nuclear Science Symposium conference record : Nuclear Science Symposium, Medical Imaging Conference ; 16 - 22 October 2004, Rome, Italy ; [including the Symposium on Nuclear Power System (SNPS), 14th Room Temperature Semiconductor X- and Gamma-Ray Detectors Workshop and special focus workshops] / NPSS, Nuclear \& Plasma Sciences Society. Guest ed.: J. Anthony Seibert}, publisher = {IEEE Operations Center}, address = {Piscataway, NJ}, issn = {1082-3654}, pages = {2430 -- 2433}, year = {2004}, language = {en} } @article{ZiemonsAuffrayBarbieretal.2005, author = {Ziemons, Karl and Auffray, E. and Barbier, R. and Brandenburg, G. and Bruyndonckx, P.}, title = {The ClearPET™ project: Development of a 2nd generation high-performance small animal PET scanner}, series = {Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment}, volume = {537}, journal = {Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment}, number = {1-2}, issn = {0168-9002}, pages = {307 -- 311}, year = {2005}, abstract = {Second generation high-performance PET scanners, called ClearPET™1, have been developed by working groups of the Crystal Clear Collaboration (CCC). High sensitivity and high spatial resolution for the ClearPET camera is achieved by using a phoswich arrangement combining two different types of lutetium-based scintillator materials: LSO from CTI and LuYAP:Ce from the CCC (ISTC project). In a first ClearPET prototype, phoswich arrangements of 8×8 crystals of 2×2×10 mm3 are coupled to multi-channel photomultiplier tubes (Hamamatsu R7600). A unit of four PMTs arranged in-line represents one of 20 sectors of the ring design. The opening diameter of the ring is 120 mm, the axial detector length is 110 mm.The PMT pulses are digitized by free-running ADCs and digital data processing determines the gamma energy, the phoswich layer and even the exact pulse starting time, which is subsequently used for coincidence detection. The gantry allows rotation of the detector modules around the field of view. Preliminary data shows a correct identification of the crystal layer about (98±1)\%. Typically the energy resolution is (23.3±0.5)\% for the luyap layer and (15.4±0.4)\% for the lso layer. early studies showed the timing resolution of 2 ns FWHM and 4.8 ns FWTM. the intrinsic spatial resolution ranges from 1.37 mm to 1.61 mm full-width of half-maximum (FWHM) with a mean of 1.48 mm FWHM. further improvements in image and energy resolution are expected when the system geometry is fully modeled.}, language = {en} } @article{HerzogPietrzykShahetal.2010, author = {Herzog, Hans and Pietrzyk, Uwe and Shah, N. Jon and Ziemons, Karl}, title = {The current state, challenges and perspectives of MR-PET}, series = {Neuroimage}, volume = {49}, journal = {Neuroimage}, number = {3}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1053-8119}, doi = {10.1016/j.neuroimage.2009.10.036}, pages = {2072 -- 2082}, year = {2010}, abstract = {Following the success of PET/CT during the last decade and the recent increasing proliferation of SPECT/CT, another hybrid imaging instrument has been gaining more and more interest: MR-PET. First combined, simultaneous PET and MR studies carried out in small animals demonstrated the feasibility of the new approach. Concurrently, some prototypes of an MR-PET scanner for simultaneous human brain studies have been built, their performance is being tested and preliminary applications have already been shown. Through this pioneering work, it has become clear that advances in the detector design are necessary for further optimization. Recently, the different issues related to the present state and future prospects of MR-PET were presented and discussed during an international 2-day workshop at the Forschungszentrum J{\"u}lich, Germany, held after, and in conjunction with, the 2008 IEEE Nuclear Science Symposium and Medical Imaging Conference in Dresden, Germany on October 27-28, 2008. The topics ranged from small animal MR-PET imaging to human MR-BrainPET imaging, new detector developments, challenges/opportunities for ultra-high field MR-PET imaging and considerations of possible future research and clinical applications. This report presents a critical summary of the contributions made to the workshop.}, language = {en} } @article{StreunBrandenburgLarueetal.2006, author = {Streun, M. and Brandenburg, G. and Larue, H. and Parl, C. and Ziemons, Karl}, title = {The data acquisition system of ClearPET neuro - a small animal PET scanner}, series = {IEEE Transactions on Nuclear Science}, volume = {53}, journal = {IEEE Transactions on Nuclear Science}, number = {3}, isbn = {0018-9499}, pages = {700 -- 703}, year = {2006}, abstract = {The Crystal Clear Collaboration has developed a modular system for a small animal PET scanner (ClearPET). The modularity allows the assembly of scanners of different sizes and characteristics in order to satisfy the specific needs of the individual member institutions. The system performs depth of interaction detection by using a phoswich arrangement combining LSO and LuYAP scintillators which are coupled to Multichannel Photomultipliers (PMTs). For each PMT a free running 40 MHz ADC digitizes the signal and the complete scintillation pulse is sampled by an FPGA and sent with 20 MB/s to a PC for preprocessing. The pulse provides information about the gamma energy and the scintillator material which identifies the interaction layer. Furthermore, the exact pulse starting time is obtained from the sampled data. This is important as no hardware coincidence detection is implemented. All single events are recorded and coincidences are identified by software. The system in J{\"u}lich (ClearPET Neuro) is equipped with 10240 crystals on 80 PMTs. The paper will present an overview of the data acquisition system.}, language = {en} } @article{HautzelTaylorKrauseetal.2001, author = {Hautzel, H. and Taylor, J. G. and Krause, B. J. and Schmitz, N. and Tellmann, L. and Ziemons, Karl and Shah, N. J. and Herzog, H. and M{\"u}ller-G{\"a}rtner, H.-W.}, title = {The motion aftereffect: more than area V5/MT? Evidence from 15O-butanol PET studies}, series = {Brain Research}, volume = {892}, journal = {Brain Research}, number = {2}, isbn = {0006-8993}, pages = {281 -- 292}, year = {2001}, abstract = {The motion aftereffect is a perceptual phenomenon which has been extensively investigated both psychologically and physiologically. Neuroimaging techniques have recently demonstrated that area V5/MT is activated during the perception of this illusion. The aim of this study was to test the hypothesis if a more broadly distributed network of brain regions subserves the motion aftereffect. To identify the neuronal structures involved in the perception of the motion aftereffect, regional cerebral blood flow (rCBF) measurements with positron emission tomography were performed in six normal volunteers. Data were analysed using SPM96. The motion-sensitive visual areas including area V5/MT were activated in both hemispheres. Additionally, the lateral parietal cortex bilaterally, the right dorsolateral prefrontal cortex, the anterior cingulate cortex and the left cerebellum showed significant increases in rCBF values during the experience of the waterfall illusion. In a further reference condition with identical attentional demand but no perception of a motion aftereffect elevated rCBF were found in these regions as well. In conclusion, our findings support the notion that the perceptual illusion of motion arises exclusively in the motion-sensitive visual area V5/MT. In addition, a more widespread network of brain regions including the prefrontal and parietal cortex is activated during the waterfall illusion which represents a non-motion aftereffect-specific subset of brain areas but is involved in more basic attentional processing and cognition.}, language = {de} } @article{TaylorSchmitzZiemonsetal.2000, author = {Taylor, J. G. and Schmitz, N. and Ziemons, Karl and Grosse-Ruyken, M.-L. and Gruber, O. and M{\"u}ller-G{\"a}rtner, H.-W. and Shah, N. J.}, title = {The network of brain areas involved in the motion aftereffect}, series = {Neuroimage}, volume = {11}, journal = {Neuroimage}, number = {4}, isbn = {1053-8119}, pages = {257 -- 270}, year = {2000}, abstract = {A network of brain areas is expected to be involved in supporting the motion aftereffect. The most active components of this network were determined by means of an fMRI study of nine subjects exposed to a visual stimulus of moving bars producing the effect. Across the subjects, common areas were identified during various stages of the effect, as well as networks of areas specific to a single stage. In addition to the well-known motion-sensitive area MT the prefrontal brain areas BA44 and 47 and the cingulate gyrus, as well as posterior sites such as BA37 and BA40, were important components during the period of the motion aftereffect experience. They appear to be involved in control circuitry for selecting which of a number of processing styles is appropriate. The experimental fMRI results of the activation levels and their time courses for the various areas are explored. Correlation analysis shows that there are effectively two separate and weakly coupled networks involved in the total process. Implications of the results for awareness of the effect itself are briefly considered in the final discussion.}, language = {en} }