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Author Brzezinski, K.; Oliver, J.F.; Gillam, J.; Rafecas, M. doi  openurl
  Title Study of a high-resolution PET system using a Silicon detector probe Type Journal Article
  Year 2014 Publication Physics in Medicine and Biology Abbreviated Journal Phys. Med. Biol.  
  Volume 59 Issue 20 Pages 6117-6140  
  Keywords PET; high-resolution imaging; Si detectors; PET insert  
  Abstract A high-resolution silicon detector probe, in coincidence with a conventional PET scanner, is expected to provide images of higher quality than those achievable using the scanner alone. Spatial resolution should improve due to the finer pixelization of the probe detector, while increased sensitivity in the probe vicinity is expected to decrease noise. A PET-probe prototype is being developed utilizing this principle. The system includes a probe consisting of ten layers of silicon detectors, each a 80 x 52 array of 1 x 1 x 1 mm(3) pixels, to be operated in coincidence with a modern clinical PET scanner. Detailed simulation studies of this system have been performed to assess the effect of the additional probe information on the quality of the reconstructed images. A grid of point sources was simulated to study the contribution of the probe to the system resolution at different locations over the field of view (FOV). A resolution phantom was used to demonstrate the effect on image resolution for two probe positions. A homogeneous source distribution with hot and cold regions was used to demonstrate that the localized improvement in resolution does not come at the expense of the overall quality of the image. Since the improvement is constrained to an area close to the probe, breast imaging is proposed as a potential application for the novel geometry. In this sense, a simplified breast phantom, adjacent to heart and torso compartments, was simulated and the effect of the probe on lesion detectability, through measurements of the local contrast recovery coefficient-to-noise ratio (CNR), was observed. The list-mode ML-EM algorithm was used for image reconstruction in all cases. As expected, the point spread function of the PET-probe system was found to be non-isotropic and vary with position, offering improvement in specific regions. Increase in resolution, of factors of up to 2, was observed in the region close to the probe. Images of the resolution phantom showed visible improvement in resolution when including the probe in the simulations. The image quality study demonstrated that contrast and spill-over ratio in other areas of the FOV were not sacrificed for this enhancement. The CNR study performed on the breast phantom indicates increased lesion detectability provided by the probe.  
  Address [Brzezinski, K.; Oliver, J. F.; Gillam, J.; Rafecas, M.] Univ Valencia, CSIC, Inst Fis Corpuscular, E-46980 Valencia, Spain, Email: brzezinski@ific.uv.es  
  Corporate Author Thesis  
  Publisher Iop Publishing Ltd Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0031-9155 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000343092300011 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 1963  
Permanent link to this record
 

 
Author AGATA Collaboration; Doncel, M.; Recchia, F.; Quintana, B.; Gadea, A.; Farnea, E. doi  openurl
  Title Experimental test of the background rejection, through imaging capability, of a highly segmented AGATA germanium detector Type Journal Article
  Year 2010 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A  
  Volume 622 Issue 3 Pages 614-618  
  Keywords Gamma spectroscopy; Gamma tracking; Imaging; Position-sensitive germanium detectors  
  Abstract The development of highly segmented germanium detectors as well as the algorithms to identify the position of the interaction within the crystal opens the possibility to locate the gamma-ray source using Compton imaging algorithms. While the Compton-suppression shield, coupled to the germanium detector in conventional arrays, works also as an active filter against the gamma rays originated outside the target, the new generation of position sensitive gamma-ray detector arrays has to fully rely on tracking capabilities for this purpose. In specific experimental conditions, as the ones foreseen at radioactive beam facilities, the ability to discriminate background radiation improves the sensitivity of the gamma spectrometer. In this work we present the results of a measurement performed at the Laboratori Nazionali di Legnaro (LNL) aiming the evaluation of the AGATA detector capabilities to discriminate the origin of the gamma rays on an event-by-event basis. It will be shown that, exploiting the Compton scattering formula, it is possible to track back gamma rays coming from different positions, assigning them to specific emitting locations. These imaging capabilities are quantified for a single crystal AGATA detector.  
  Address [Doncel, M.; Quintana, B.] Univ Salamanca, Lab Radiac Ionizantes, E-37008 Salamanca, Spain, Email: doncel@usal.es  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0168-9002 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000282562700017 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 257  
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Author AGATA Collaboration (Soderstrom, P.A. et al); Gadea, A. doi  openurl
  Title Interaction position resolution simulations and in-beam measurements of the AGATA HPGe detectors Type Journal Article
  Year 2011 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A  
  Volume 638 Issue 1 Pages 96-109  
  Keywords gamma-ray tracking; AGATA; Monte Carlo simulations; HPGe detectors; Fusion-evaporation reactions  
  Abstract The interaction position resolution of the segmented HPGe detectors of an AGATA triple cluster detector has been studied through Monte Carlo simulations and in an in-beam experiment. A new method based on measuring the energy resolution of Doppler-corrected gamma-ray spectra at two different target to detector distances is described. This gives the two-dimensional position resolution in the plane perpendicular to the direction of the emitted gamma-ray. The gamma-ray tracking was used to determine the full energy of the gamma-rays and the first interaction point, which is needed for the Doppler correction. Five different heavy-ion induced fusion-evaporation reactions and a reference reaction were selected for the simulations. The results of the simulations show that the method works very well and gives a systematic deviation of <1 mm in the FVVHM of the interaction position resolution for the gamma-ray energy range from 60 keV to 5 MeV. The method was tested with real data from an in-beam measurement using a (30)5i beam at 64 MeV on a thin C-12 target. Pulse-shape analysis of the digitized detector waveforms and gamma-ray tracking was performed to determine the position of the first interaction point, which was used for the Doppler corrections. Results of the dependency of the interaction position resolution on the gamma-ray energy and on the energy, axial location and type of the first interaction point, are presented. The FVVHM of the interaction position resolution varies roughly linearly as a function of gamma-ray energy from 8.5 mm at 250 key to 4 mm at 1.5 MeV, and has an approximately constant value of about 4 mm in the gamma-ray energy range from 1.5 to 4 MeV.  
  Address [Soderstrom, P. -A.; Nyberg, J.; Al-Adili, A.; Atac, A.; Veyssiere, C.] Uppsala Univ, Dept Phys & Astron, SE-75121 Uppsala, Sweden, Email: P-A.Soderstrom@physics.uu.se  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0168-9002 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000290082600015 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 619  
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Author Labiche, M. et al; Caballero, L.; Rubio, B. url  doi
openurl 
  Title TIARA: A large solid angle silicon array for direct reaction studies with radioactive beams Type Journal Article
  Year 2010 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A  
  Volume 614 Issue 3 Pages 439-448  
  Keywords Position sensitive silicon detectors; Nucleon transfer reactions; Radioactive beams; Inverse kinematics  
  Abstract A compact, quasi-4 pi position sensitive silicon array. TIARA, designed to study direct reactions induced by radioactive beams in inverse kinematics is described here. The Transfer and Inelastic All-angle Reaction Array (TIARA) consists of 8 resistive charge division detectors forming an octagonal barrel around the target and a set of double-sided silicon-strip annular detectors positioned at each end of the barrel. The detector was coupled to the gamma-ray array EXOGAM and the spectrometer VAMOS at the GANIL Laboratory to demonstrate the potential of such an apparatus with radioactive beams. The N-14(d,p)N-15 reaction, well known in direct kinematics, has been carried out in inverse kinematics for that purpose. The observation of the N-15 ground state and excited states at 7.16 and 7.86 MeV is presented here as well as the comparison of the measured proton angular distributions with DWBA calculations. Transferred l-values are in very good agreement with both theoretical calculations and previous experimental results obtained in direct kinematics.  
  Address [Labiche, M.; Lemmon, R. C.; Appleton, S.; Faiz, K.; Pucknell, V. F. E.; Warner, D. D.] STFC Daresbury Lab, Nucl Phys Grp, Warrington WA4 4AD, Cheshire, England, Email: marc.labiche@stfc.ac.uk  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0168-9002 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000276001800008 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ elepoucu @ Serial 477  
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Author Langer, C.; Algora, A.; Couture, A.; Csatlos, M.; Gulyas, J.; Heil, M.; Krasznahorkay, A.; O'Donnell, J.M.; Plag, R.; Reifarth, R.; Stuhl, L.; Sonnabend, K.; Tornyi, T.; Tovesson, F. doi  openurl
  Title Simulations and developments of the Low Energy Neutron detector Array LENA Type Journal Article
  Year 2011 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A  
  Volume 659 Issue 1 Pages 411-418  
  Keywords Monte Carlo simulations; Charge-exchange reactions; Scintillation detectors; Neutron detector  
  Abstract Prototypes of the Low Energy Neutron detector Array (LENA) have been tested and compared with detailed GEANT simulations. LENA will consist of plastic scintillation bars with the dimensions 1000 x 45 x 10 mm(3). The tests have been performed with gamma-ray sources and neutrons originating from the neutron-induced fission of (235)U. The simulations agreed very well with the measured response and were therefore used to simulate the response to mono-energetic neutrons with different detection thresholds. LENA will be used to detect low-energy neutrons from (p,n)-type reactions with low momentum transfer foreseen at the R(3)B and EXL setups at FAIR, Darmstadt.  
  Address [Langer, C.; Heil, M.; Plag, R.; Reifarth, R.] GSI Helmholtzzentrum Schwerionenforsch GmbH, D-64291 Darmstadt, Germany, Email: c.langer@gsi.de  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0168-9002 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000297826100057 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 833  
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Author Affolder, A. et al; Garcia, C.; Lacasta, C.; Marco, R.; Marti-Garcia, S.; Miñano, M.; Soldevila, U. doi  openurl
  Title Silicon detectors for the sLHC Type Journal Article
  Year 2011 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A  
  Volume 658 Issue 1 Pages 11-16  
  Keywords Silicon particle detectors; Radiation damage; Irradiation; Charge collection efficiency  
  Abstract In current particle physics experiments, silicon strip detectors are widely used as part of the inner tracking layers. A foreseeable large-scale application for such detectors consists of the luminosity upgrade of the Large Hadron Collider (LHC), the super-LHC or sLHC, where silicon detectors with extreme radiation hardness are required. The mission statement of the CERN RD50 Collaboration is the development of radiation-hard semiconductor devices for very high luminosity colliders. As a consequence, the aim of the R&D programme presented in this article is to develop silicon particle detectors able to operate at sLHC conditions. Research has progressed in different areas, such as defect characterisation, defect engineering and full detector systems. Recent results from these areas will be presented. This includes in particular an improved understanding of the macroscopic changes of the effective doping concentration based on identification of the individual microscopic defects, results from irradiation with a mix of different particle types as expected for the sLHC, and the observation of charge multiplication effects in heavily irradiated detectors at very high bias voltages.  
  Address [Barber, T.; Breindl, M.; Driewer, A.; Koehler, M.; Kuehn, S.; Parzefall, U.; Preiss, J.; Walz, M.; Wiik, L.] Univ Freiburg, Inst Phys, D-79104 Freiburg, Germany, Email: Ulrich.Parzefall@physik.uni-freiburg.de  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0168-9002 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000297783300004 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 836  
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Author AGATA Collaboration (Akkoyun, S. et al); Algora, A.; Barrientos, D.; Domingo-Pardo, C.; Egea, F.J.; Gadea, A.; Huyuk, T.; Kaci, M.; Mendez, V.; Rubio, B.; Salt, J.; Tain, J.L. url  doi
openurl 
  Title AGATA-Advanced GAmma Tracking Array Type Journal Article
  Year 2012 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A  
  Volume 668 Issue Pages 26-58  
  Keywords AGATA; gamma-Ray spectroscopy; gamma-Ray tracking; HPGe detectors; Digital signal processing; Pulse-shape and gamma-ray tracking algorithms; Semiconductor detector performance and simulations  
  Abstract The Advanced GAmma Tracking Array (AGATA) is a European project to develop and operate the next generation gamma-ray spectrometer. AGATA is based on the technique of gamma-ray energy tracking in electrically segmented high-purity germanium crystals. This technique requires the accurate determination of the energy, time and position of every interaction as a gamma ray deposits its energy within the detector volume. Reconstruction of the full interaction path results in a detector with very high efficiency and excellent spectral response. The realisation of gamma-ray tracking and AGATA is a result of many technical advances. These include the development of encapsulated highly segmented germanium detectors assembled in a triple cluster detector cryostat, an electronics system with fast digital sampling and a data acquisition system to process the data at a high rate. The full characterisation of the crystals was measured and compared with detector-response simulations. This enabled pulse-shape analysis algorithms, to extract energy, time and position, to be employed. In addition, tracking algorithms for event reconstruction were developed. The first phase of AGATA is now complete and operational in its first physics campaign. In the future AGATA will be moved between laboratories in Europe and operated in a series of campaigns to take advantage of the different beams and facilities available to maximise its science output. The paper reviews all the achievements made in the AGATA project including all the necessary infrastructure to operate and support the spectrometer.  
  Address [Boston, A. J.; Boston, H. C.; Colosimo, S.; Cooper, R. J.; Cresswell, J. R.; Dimmock, M. R.; Filmer, F.; Grint, A. N.; Harkness, L. J.; Judson, D. S.; Mather, A. R.; Moon, S.; Nelson, L.; Nolan, P. J.; Norman, M.; Oxley, D. C.; Rigby, S.; Sampson, J.; Scraggs, D. P.; Seddon, D.; Slee, M.; Stanios, T.; Thornhill, J.; Unsworth, C.; Wells, D.] Univ Liverpool, Oliver Lodge Lab, Liverpool L69 7ZE, Merseyside, England, Email: a.j.boston@liverpool.ac.uk  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0168-9002 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000300864200005 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 923  
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Author Studen, A.; Chesi, E.; Cindro, V.; Clinthorne, N.H.; Cochran, E.; Grosicar, B.; Honscheid, K.; Kagan, H.; Lacasta, C.; Llosa, G.; Linhart, V.; Mikuz, M.; Stankova, V.; Weilhammer, P.; Zontar, D. doi  openurl
  Title A silicon PET probe Type Journal Article
  Year 2011 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A  
  Volume 648 Issue Pages S255-S258  
  Keywords PET; Silicon detectors  
  Abstract PET scanners with high spatial resolution offer a great potential in improving diagnosis, therapy monitoring and treatment validation for several severe diseases. One way to improve resolution of a PET scanner is to extend a conventional PET ring with a small probe with excellent spatial resolution. The probe is intended to be placed close to the area of interest. The coincidences of interactions within the probe and the external ring provide a subset of data which combined with data from external ring, greatly improve resolution in the area viewed by the probe. Our collaboration is developing a prototype of a PET probe, composed of high-resolution silicon pad detectors. The detectors are 1 mm thick, measuring 40 by 26 mm(2), and several such sensors are envisaged to either compensate for low stopping power of silicon or increase the area covered by the probe. The sensors are segmented into 1 mm(3) cubic voxels, giving 1040 readout pads per sensor. A module is composed of two sensors placed in a back-to-back configuration, allowing for stacking fraction of up to 70% within a module. The pads are coupled to a set of 16 ASICs (VaTaGP7.1 by IDEAS) per module and read out through a custom designed data acquisition board, allowing for trigger and data interfacing with the external ring. This paper presents an overview of probe requirements and expected performance parameters. It will focus on the characteristics of the silicon modules and their impact on overall probe performance, including spatial resolution, energy resolution and timing resolution. We will show that 1 mm(3) voxels will significantly extend the spatial resolution of conventional PET rings, and that broadening of timing resolution related to varying depth of photon interactions can be compensated to match the timing resolution of the external ring. The initial test results of the probe will also be presented.  
  Address [Studen, A.; Cindro, V.; Grosicar, B.; Mikuz, M.; Zontar, D.] Jozef Stefan Inst, Ljubljana, Slovenia, Email: andrej.studen@ijs.si  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0168-9002 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000305376900063 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 1070  
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Author AGATA Collaboration; Doncel, M.; Quintana, B.; Gadea, A.; Recchia, F.; Farnea, E. doi  openurl
  Title Background rejection capabilities of a Compton imaging telescope setup with a DSSD Ge planar detector and AGATA Type Journal Article
  Year 2011 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A  
  Volume 648 Issue Pages S131-S134  
  Keywords gamma-Spectroscopy; Gamma tracking; Imaging; Position-sensitive germanium detectors  
  Abstract In this work, we show the first Monte Carlo results about the performance of the Ge array which we propose for the DESPEC experiment at FAIR, when the background algorithm developed for AGATA is applied. The main objective of our study is to characterize the capabilities of the gamma-spectroscopy system, made up of AGATA detectors in a semi-spherical distribution covering a 1 pi solid angle and a set of planar Ge detectors in a daisy configuration, to discriminate between gamma sources placed at different locations.  
  Address [Doncel, M.; Quintana, B.] Univ Salamanca, Lab Radiac Ionizantes, E-37008 Salamanca, Spain, Email: doncel@usal.es  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0168-9002 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000305376900035 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 1071  
Permanent link to this record
 

 
Author Blanco, A.; Belver, D.; Cabanelas, P.; Diaz, J.; Fonte, P.; Garzon, J.A.; Gil, A.; Gonzalez-Diaz, D.; Koenig, W.; Kolb, B.; Lopes, L.; Palka, M.; Pereira, A.; Traxler, M.; Zumbruch, P. doi  openurl
  Title RPC HADES-TOF wall cosmic ray test performance Type Journal Article
  Year 2012 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A  
  Volume 661 Issue Pages S114-S117  
  Keywords Gaseous detectors; Timing; TOF; RPC; HADES  
  Abstract In this work we present results concerning the cosmic ray test, prior to the final installation and commissioning of the new Resistive Plate Chamber (RPC) Time of Flight (TOF) wall for the High-Acceptance DiElectron Spectrometer (HADES) at GSI. The TOF wall is composed of six equal sectors, each one constituted by 186 individual 4-gaps glass-aluminium shielded RPC cells distributed in six columns and 31 rows in two partially overlapping layers, covering an area of 1.26 m(2). All sectors were tested with the final Front End Electronic (FEE) and Data AcQuisition system (DAQ) together with Low Voltage (LV) and High Voltage (HV) systems. Results confirm a very uniform average system time resolution of 77 ps sigma together with an average multi-hit time resolution of 83 ps. Crosstalk levels below 1% (in average), moderate timing tails along with an average longitudinal position resolution of 8.4 mm sigma are also confirmed.  
  Address [Blanco, A.; Fonte, P.; Lopes, L.; Pereira, A.] LIP, Lab Instrumentacao & Fis Expt Particulas, Coimbra, Portugal, Email: alberto@coimbra.lip.pt  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0168-9002 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000311568900029 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 1285  
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