| |
Records |
Links |
|
Author |
Roser, J.; Barrientos, L.; Bernabeu, J.; Borja-Lloret, M.; Muñoz, E.; Ros, A.; Viegas, R.; Llosa, G. |
|
| |
Title |
Joint image reconstruction algorithm in Compton cameras |
Type |
Journal Article |
| |
Year |
2022 |
Publication  |
Physics in Medicine and Biology |
Abbreviated Journal |
Phys. Med. Biol. |
|
| |
Volume |
67 |
Issue |
15 |
Pages |
155009 - 15pp |
|
| |
Keywords |
Compton camera; compton imaging; hadron therapy; image reconstruction; LM-MLEM; Monte Carlo simulations; multi-layer compton telescope |
|
| |
Abstract |
Objective. To demonstrate the benefits of using an joint image reconstruction algorithm based on the List Mode Maximum Likelihood Expectation Maximization that combines events measured in different channels of information of a Compton camera. Approach. Both simulations and experimental data are employed to show the algorithm performance. Main results. The obtained joint images present improved image quality and yield better estimates of displacements of high-energy gamma-ray emitting sources. The algorithm also provides images that are more stable than any individual channel against the noisy convergence that characterizes Maximum Likelihood based algorithms. Significance. The joint reconstruction algorithm can improve the quality and robustness of Compton camera images. It also has high versatility, as it can be easily adapted to any Compton camera geometry. It is thus expected to represent an important step in the optimization of Compton camera imaging. |
|
| |
Address |
[Roser, J.; Barrientos, L.; Bernabeu, J.; Borja-Lloret, M.; Munoz, E.; Ros, A.; Viegas, R.; Llosa, G.] CSIC UV, Inst Fis Corpuscular IFIC, Valencia, Spain, Email: Jorge.Roser@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 |
0031-9155 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
WOS:000827830200001 |
Approved |
no |
|
| |
Is ISI |
yes |
International Collaboration |
no |
|
| |
Call Number |
IFIC @ pastor @ |
Serial |
5298 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Borja-Lloret, M.; Barrientos, L.; Bernabeu, J.; Lacasta, C.; Muñoz, E.; Ros, A.; Roser, J.; Viegas, R.; Llosa, G. |
|
| |
Title |
Influence of the background in Compton camera images for proton therapy treatment monitoring |
Type |
Journal Article |
| |
Year |
2023 |
Publication |
Physics in Medicine and Biology |
Abbreviated Journal |
Phys. Med. Biol. |
|
| |
Volume |
68 |
Issue |
14 |
Pages |
144001 - 16pp |
|
| |
Keywords |
Compton imaging; Compton camera; proton therapy; treatment monitoring; Monte Carlo simulation; image reconstruction; background |
|
| |
Abstract |
Objective. Background events are one of the most relevant contributions to image degradation in Compton camera imaging for hadron therapy treatment monitoring. A study of the background and its contribution to image degradation is important to define future strategies to reduce the background in the system. Approach. In this simulation study, the percentage of different kinds of events and their contribution to the reconstructed image in a two-layer Compton camera have been evaluated. To this end, GATE v8.2 simulations of a proton beam impinging on a PMMA phantom have been carried out, for different proton beam energies and at different beam intensities. Main results. For a simulated Compton camera made of Lanthanum (III) Bromide monolithic crystals, coincidences caused by neutrons arriving from the phantom are the most common type of background produced by secondary radiations in the Compton camera, causing between 13% and 33% of the detected coincidences, depending on the beam energy. Results also show that random coincidences are a significant cause of image degradation at high beam intensities, and their influence in the reconstructed images is studied for values of the time coincidence windows from 500 ps to 100 ns. Significance. Results indicate the timing capabilities required to retrieve the fall-off position with good precision. Still, the noise observed in the image when no randoms are considered make us consider further background rejection methods. |
|
| |
Address |
[Borja-Lloret, M.; Barrientos, L.; Bernabeu, J.; Lacasta, C.; Munoz, E.; Ros, A.; Roser, J.; Viegas, R.; Llosa, G.] Inst Fis Corpuscular IFIC, CSIC UV, Valencia, Spain, Email: Marina.Borja@csic.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 |
0031-9155 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
WOS:001022671300001 |
Approved |
no |
|
| |
Is ISI |
yes |
International Collaboration |
no |
|
| |
Call Number |
IFIC @ pastor @ |
Serial |
5571 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Krzysiek, M. et al; Gadea, A.; Huyuk, T.; Barrientos, D. |
|
| |
Title |
Study of the soft dipole modes in Ce-140 via inelastic scattering of O-17 |
Type |
Journal Article |
| |
Year |
2014 |
Publication |
Physica Scripta |
Abbreviated Journal |
Phys. Scr. |
|
| |
Volume |
89 |
Issue |
5 |
Pages |
054016 - 6pp |
|
| |
Keywords |
pygmy dipole resonances; inelastic scattering; AGATA detector; gamma spectroscopy |
|
| |
Abstract |
The main aim of this study was a deeper understanding of the nuclear structure properties of the soft dipole modes in Ce-140, excited via inelastic scattering of weakly bound O-17 projectiles. An important aim was to investigate the 'splitting' of the PDR into two parts: a low-energy isoscalar component dominated by neutron-skin oscillations and a higher-energy component lying on the tail of the giant dipole resonance of a rather isovector character. This was already observed for this nucleus, investigated in (alpha, alpha') and (gamma,gamma') experiments. The experiment was performed at Laboratori Nazionali di Legnaro, Italy. Inelastic scattering of O-17 ion beam at 20 MeV A(-1) was used to excite the resonance modes in the Ce-140 target. Gamma-rays were registered by five triple clusters of AGATA-Demonstrator and nine large volume scintillators (LaBr3). The scattered O-17 ions were identified by two Delta E – E Si telescopes of the TRACE array mounted inside the scattering chamber. The telescopes consisted of two segmented Si-pad detectors, each of 60 pixels. Very preliminary data have shown a strong domination of the E1 transitions in the 'pygmy' region with a character more similar to the one obtained in alpha scattering experiment. |
|
| |
Address |
[Krzysiek, M.; Kmiecik, M.; Maj, A.; Bednarczyk, P.; Ciemala, M.; Fornal, B.; Grebosz, J.; Mazurek, K.; Meczynski, W.; Zieblinski, M.] Polish Acad Sci, H Niewodniczanski Inst Nucl Phys, Krakow, Poland, Email: mateusz.krzysiek@ifj.edu.pl |
|
| |
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 |
0031-8949 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
WOS:000335785300016 |
Approved |
no |
|
| |
Is ISI |
yes |
International Collaboration |
yes |
|
| |
Call Number |
IFIC @ pastor @ |
Serial |
1790 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
AGATA Collaboration (Ralet, D. et al); Gadea, A.; Perez-Vidal, R.M. |
|
| |
Title |
Toward lifetime and g factor measurements of short-lived states in the vicinity of Pb-208 |
Type |
Journal Article |
| |
Year |
2017 |
Publication |
Physica Scripta |
Abbreviated Journal |
Phys. Scr. |
|
| |
Volume |
92 |
Issue |
5 |
Pages |
054004 - 4pp |
|
| |
Keywords |
multi-nucleon transfer reaction; lifetime measurement; AGATA; VAMOS plus |
|
| |
Abstract |
The multi-nucleon transfer reaction mechanism was used to produce and study nuclei in the vicinity of 208Pb. This mass region is a test case for the nuclear shell model. The mass identification of the fragments was performed with the large acceptance magnetic spectrometer VAMOS++ coupled to the AGATA gamma-tracking array. This experiment aimed to determine both lifetimes and gyromagnetic ratios of excited states with the Cologne plunger device. The analysis indicates promising results with the possibility to determine several new lifetimes in this region. |
|
| |
Address |
[Ralet, D.; Georgiev, G.; Konstantinopoulos, T.; Korichi, A.; Ljungvall, J.] Univ Paris Saclay, Univ Paris Sud, CNRS IN2P3, CSNSM, F-91405 Orsay, France, Email: damian.ralet@csnsm.in2p3.fr |
|
| |
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 |
0031-8949 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
WOS:000399888300001 |
Approved |
no |
|
| |
Is ISI |
yes |
International Collaboration |
yes |
|
| |
Call Number |
IFIC @ pastor @ |
Serial |
3092 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Pajtler, M.V. et al; Gadea, A. |
|
| |
Title |
Excited states of Y-90,Y-92,Y-94 populated in Zr-90+Pb-208 multinucleon transfer reaction |
Type |
Journal Article |
| |
Year |
2021 |
Publication |
Physica Scripta |
Abbreviated Journal |
Phys. Scr. |
|
| |
Volume |
96 |
Issue |
3 |
Pages |
035305 - 7pp |
|
| |
Keywords |
multinucleon transfer reactions; gamma spectroscopy; magnetic spectrometers; gamma-ray spectrometers |
|
| |
Abstract |
Multinucleon transfer reactions in Zr-90+Pb-208 have been studied via fragment-gamma coincidences, employing the PRISMA magnetic spectrometer coupled to the CLARA gamma-array. An analysis on Y isotopes has been carried out incorporating spectroscopic as well as reaction mechanism aspects. New gamma transitions have been observed in Y-94, confirming the findings of recent studies where nuclei were produced via fission of uranium, and a comparison with near-by Y-90,Y-92 isotopes populated in the same reaction has been discussed. Experimental cross sections have been extracted and compared with the GRAZING calculations, showing a fair agreement along the neutron pick-up side. The results confirm how multinucleon transfer reactions are a suitable mechanism for the study of neutron-rich nuclei. |
|
| |
Address |
[Pajtler, M. Varga] Univ Osijek, Dept Phys, Osijek, Croatia, Email: Suzana.Szilner@irb.hr; |
|
| |
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 |
0031-8949 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
WOS:000611517400001 |
Approved |
no |
|
| |
Is ISI |
yes |
International Collaboration |
yes |
|
| |
Call Number |
IFIC @ pastor @ |
Serial |
4694 |
|
| Permanent link to this record |
