Records |
Author |
Clinthorne, N.; Brzezinski, K.; Chesi, E.; Cochran, E.; Grkovski, M.; Grosicar, B.; Honscheid, K.; Huh, S.; Kagan, H.; Lacasta, C.; Linhart, V.; Mikuz, M.; Smith, D.S.; Stankova, V.; Studen, A.; Weilhammer, P.; Zontar, D. |
Title |
Silicon as an unconventional detector in positron emission tomography |
Type |
Journal Article |
Year |
2013 |
Publication |
Nuclear Instruments & Methods in Physics Research A |
Abbreviated Journal |
Nucl. Instrum. Methods Phys. Res. A |
Volume |
699 |
Issue |
|
Pages |
216-220 |
Keywords |
PET; Silicon detectors; Multiresolution imaging; Magnifying PET |
Abstract |
Positron emission tomography (PET) is a widely used technique in medical imaging and in studying small animal models of human disease. In the conventional approach, the 511 keV annihilation photons emitted from a patient or small animal are detected by a ring of scintillators such as LYSO read out by arrays of photodetectors. Although this has been successful in achieving similar to 5 mm FWHM spatial resolution in human studies and similar to 1 mm resolution in dedicated small animal instruments, there is interest in significantly improving these figures. Silicon, although its stopping power is modest for 511 keV photons, offers a number of potential advantages over more conventional approaches including the potential for high intrinsic spatial resolution in 3D. To evaluate silicon in a variety of PET “magnifying glass” configurations, an instrument was constructed that consists of an outer partial-ring of PET scintillation detectors into which various arrangements of silicon detectors are inserted to emulate dual-ring or imaging probe geometries. Measurements using the test instrument demonstrated the capability of clearly resolving point sources of Na-22 having a 1.5 mm center-to-center spacing as well as the 1.2 mm rods of a F-18-filled resolution phantom. Although many challenges remain, silicon has potential to become the PET detector of choice when spatial resolution is the primary consideration. (C) 2012 Elsevier B.V. All rights reserved. |
Address |
[Clinthorne, Neal; Huh, Sam] Univ Michigan, Dept Radiol, Ann Arbor, MI 48109 USA, Email: nclintho@umich.edu |
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 ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
0168-9002 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000312809200045 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1290 |
Permanent link to this record |
|
|
|
Author |
AGATA Collaboration (Crespi, F.C.L. et al); Gadea, A. |
Title |
Response of AGATA segmented HPGe detectors to gamma rays up to 15.1 MeV |
Type |
Journal Article |
Year |
2013 |
Publication |
Nuclear Instruments & Methods in Physics Research A |
Abbreviated Journal |
Nucl. Instrum. Methods Phys. Res. A |
Volume |
705 |
Issue |
|
Pages |
47-54 |
Keywords |
AGATA; Gamma-ray spectroscopy; Gamma-ray tracking; HPGe detectors; Pulse-shape and gamma-ray tracking algorithms; Semiconductor detector performance and simulations |
Abstract |
The response of AGATA segmented HPGe detectors to gamma rays in the energy range 2-15 MeV was measured. The 15.1 MeV gamma rays were produced using the reaction d(B-11,n gamma)C-12 at E-beam=19.1 MeV, while gamma rays between 2 and 9 MeV were produced using an Am-Be-Fe radioactive source. The energy resolution and linearity were studied and the energy-to-pulse-height conversion resulted to be linear within 0.05%.Experimental interaction multiplicity distributions are discussed and compared with the results of Geant4 simulations. It is shown that the application of gamma-ray tracking allows a suppression of background radiation caused by n-capture in Ge nuclei. Finally the Doppler correction for the 15.1 MeV gamma line, performed using the position information extracted with Pulse-shape analysis is discussed. |
Address |
[Crespi, F. C. L.; Avigo, R.; Camera, F.; Bottoni, S.; Bracco, A.; Ceruti, S.; Giaz, A.; Leoni, S.; Nicolini, R.; Pellegri, L.; Riboldi, S.; Vandone, V.] Univ Milan, Dipartimento Fis, I-20133 Milan, Italy, Email: fabio.crespi@mi.infn.it |
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 ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
0168-9002 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000314826000009 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1329 |
Permanent link to this record |
|
|
|
Author |
Studen, A.; Brzezinski, K.; Chesi, E.; Cindro, V.; Clinthorne, N.H.; Cochran, E.; Grosicar, B.; Grkovski, M.; Honscheid, K.; Kagan, H.; Lacasta, C.; Llosa, G.; Mikuz, M.; Stankova, V.; Weilhammer, P.; Zontar, D. |
Title |
Silicon detectors for combined MR-PET and MR-SPECT imaging |
Type |
Journal Article |
Year |
2013 |
Publication |
Nuclear Instruments & Methods in Physics Research A |
Abbreviated Journal |
Nucl. Instrum. Methods Phys. Res. A |
Volume |
702 |
Issue |
|
Pages |
88-90 |
Keywords |
PET; Silicon detectors; SPECT |
Abstract |
Silicon based devices can extend PET-MR and SPECT-MR imaging to applications, where their advantages in performance outweigh benefits of high statistical counts. Silicon is in many ways an excellent detector material with numerous advantages, among others: excellent energy and spatial resolution, mature processing technology, large signal to noise ratio, relatively low price, availability, versatility and malleability. The signal in silicon is also immune to effects of magnetic field at the level normally used in MR devices. Tests in fields up to 7 T were performed in a study to determine effects of magnetic field on positron range in a silicon PET device. The curvature of positron tracks in direction perpendicular to the field's orientation shortens the distance between emission and annihilation point of the positron. The effect can be fully appreciated for a rotation of the sample for a fixed field direction, compressing range in all dimensions. A popular Ga-68 source was used showing a factor of 2 improvement in image noise compared to zero field operation. There was also a little increase in noise as the reconstructed resolution varied between 2.5 and 1.5 mm. A speculative applications can be recognized in both emission modalities, SPECT and PET. Compton camera is a subspecies of SPECT, where a silicon based scatter as a MR compatible part could inserted into the MR bore and the secondary detector could operate in less constrained environment away from the magnet. Introducing a Compton camera also relaxes requirements of the radiotracers used, extending the range of conceivable photon energies beyond 140.5 keV of the Tc-99m. In PET, one could exploit the compressed sub-millimeter range of positrons in the magnetic field. To exploit the advantage, detectors with spatial resolution commensurate to the effect must be used with silicon being an excellent candidate. Measurements performed outside of the MR achieving spatial resolution below 1 mm are reported. |
Address |
[Studen, A.; Cindro, V.; Grosicar, B.; Grkovski, M.; 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 ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
0168-9002 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000314682300026 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1331 |
Permanent link to this record |
|
|
|
Author |
n_TOF Collaboration (Tarrio, D. et al); Domingo-Pardo, C.; Giubrone, G.; Tain, J.L. |
Title |
Measurement of the angular distribution of fission fragments using a PPAC assembly at CERN n_TOF |
Type |
Journal Article |
Year |
2014 |
Publication |
Nuclear Instruments & Methods in Physics Research A |
Abbreviated Journal |
Nucl. Instrum. Methods Phys. Res. A |
Volume |
743 |
Issue |
|
Pages |
79-85 |
Keywords |
Fission; Neutron; Anisotropy; Angular distribution; Th-232; Gas detectors |
Abstract |
A fission reaction chamber based on Parallel Plate Avalanche Counters (PPACs) was built for measuring angular distributions of fragments emitted in neutron-induced fission of actinides at the neutron beam available at the Neutron Time-Of-Flight (n_TOF) facility at CERN. The detectors and the samples were tilted 45 degrees with respect to the neutron beam direction to cover all the possible values of the emission angle of the fission fragments. The main features of this setup are discussed and results on the fission fragment angular distribution are provided for the Th-232(n,f) reaction around the fission threshold. The results are compared with the available data in the literature, demonstrating the good capabilities of this setup. |
Address |
[Tarrio, D.; Duran, I.; Paradela, C.; Caamano, M.] Univ Santiago de Compostela, Santiago De Compostela, Spain, Email: dtarriov@gmail.com |
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 ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
0168-9002 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000334005000011 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1746 |
Permanent link to this record |
|
|
|
Author |
Ullan, M.; Benitez, V.; Quirion, D.; Zabala, M.; Pellegrini, G.; Lozano, M.; Lacasta, C.; Soldevila, U.; Garcia, C.; Fadeyev, V.; Wortman, J.; DeFilippis, J.; Shumko, M.; Grillo, A.A.; Sadrozinski, H.F.W. |
Title |
Low-resistance strip sensors for beam-loss event protection |
Type |
Journal Article |
Year |
2014 |
Publication |
Nuclear Instruments & Methods in Physics Research A |
Abbreviated Journal |
Nucl. Instrum. Methods Phys. Res. A |
Volume |
765 |
Issue |
|
Pages |
252-257 |
Keywords |
Silicon radiation detectors; Strip sensors; Punch through protection; Beam loss; HL-LHC; ATLAS Upgrade |
Abstract |
AC coupled silicon strip sensors can be damaged in case of a beam loss due to the possibility of a large charge accumulation in the bulk, developing very high voltages across the coupling capacitors which can destroy them. Punch-through structures are currently used to avoid this problem helping to evacuate the accumulated charge as large voltages are developing. Nevertheless, previous experiments, performed with laser pulses, have shown that these structures can become ineffective in relatively long strips. The large value of the implant resistance can effectively isolate the “far” end of the strip from the punchthrough structure leading to large voltages. We present here our developments to fabricate lowresistance strip sensors to avoid this problem. The deposition of a conducting material in contact with the implants drastically reduces the strip resistance, assuring the effectiveness of the punch-through structures. First devices have been fabricated with this new technology. Initial results with laser tests show the expected reduction in peak voltages on the low resistivity implants. Other aspects of the sensor performance, including the signal formation, are not affected by the new technology. |
Address |
[Ullan, M.; Benitez, V.; Quirion, D.; Zabala, M.; Pellegrini, G.; Lozano, M.] CSIC, Ctr Nacl Microelect IMB CNM, Barcelona 08193, Spain, Email: Miguel.Ullan@imb-cnm.csic.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 ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
0168-9002 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000344621000048 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2003 |
Permanent link to this record |