Records |
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 |
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Thesis |
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Publisher |
IOP Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0031-9155 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
|
Notes |
WOS:000827830200001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ pastor @ |
Serial |
5298 |
Permanent link to this record |
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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 |
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Thesis |
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Publisher |
IOP Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0031-9155 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
|
Notes |
WOS:001022671300001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ pastor @ |
Serial |
5571 |
Permanent link to this record |
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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 |
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Thesis |
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Publisher |
Iop Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0031-8949 |
ISBN |
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Medium |
|
Area |
|
Expedition |
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Conference |
|
Notes |
WOS:000335785300016 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1790 |
Permanent link to this record |
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Author |
Davesne, D.; Meyer, J.; Pastore, A.; Navarro, J. |
Title |
Partial wave decomposition of the N3LO equation of state |
Type |
Journal Article |
Year |
2015 |
Publication |
Physica Scripta |
Abbreviated Journal |
Phys. Scr. |
Volume |
90 |
Issue |
11 |
Pages |
114002 - 6pp |
Keywords |
nuclear structure; equation of state; effective theory |
Abstract |
By means of a partial wave decomposition, we separate their contributions to the equation of state (EoS) of symmetric nuclear matter for the N3LO pseudo-potential. In particular, we show that although both the tensor and the spin-orbit terms do not contribute to the EoS, they give a non-vanishing contribution to the separate (JLS) channels. |
Address |
[Davesne, D.; Meyer, J.] Univ Lyon 1, CNRS, IN2P3, Inst Phys Nucl Lyon,UMR 5822, F-69622 Villeurbanne, France, Email: davesne@ipnl.in2p3.fr; |
Corporate Author |
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Thesis |
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Publisher |
Iop Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0031-8949 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
|
Notes |
WOS:000366871100003 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2508 |
Permanent link to this record |
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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 |
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Thesis |
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Publisher |
Iop Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0031-8949 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
|
Notes |
WOS:000399888300001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3092 |
Permanent link to this record |
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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 |
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Thesis |
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Publisher |
Iop Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0031-8949 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
|
Notes |
WOS:000611517400001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4694 |
Permanent link to this record |
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Author |
Ferreira, M.N.; Papavassiliou, J. |
Title |
Gauge Sector Dynamics in QCD |
Type |
Journal Article |
Year |
2023 |
Publication |
Particles |
Abbreviated Journal |
Particles |
Volume |
6 |
Issue |
1 |
Pages |
312-363 |
Keywords |
continuum Schwinger function methods; emergence of hadron mass; gluon mass generation; lattice QCD; non-perturbative quantum field theory; quantum chromodynamics; Schwinger-Dyson equations; Schwinger mechanism |
Abstract |
The dynamics of the QCD gauge sector give rise to non-perturbative phenomena that are crucial for the internal consistency of the theory; most notably, they account for the generation of a gluon mass through the action of the Schwinger mechanism, the taming of the Landau pole, the ensuing stabilization of the gauge coupling, and the infrared suppression of the three-gluon vertex. In the present work, we review some key advances in the ongoing investigation of this sector within the framework of the continuum Schwinger function methods, supplemented by results obtained from lattice simulations. |
Address |
[Ferreira, Mauricio Narciso; Papavassiliou, Joannis] Univ Valencia, Dept Theoret Phys, E-46100 Valencia, Spain, Email: ansonar@uv.es; |
Corporate Author |
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Thesis |
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Publisher |
Mdpi |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
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ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000959126400001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ pastor @ |
Serial |
5504 |
Permanent link to this record |
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Author |
Cervantes, D.; Fioresi, R.; Lledo, M.A.; Nadal, F.A. |
Title |
Quantum Twistors |
Type |
Journal Article |
Year |
2016 |
Publication |
P-Adic Numbers Ultrametric Analysis and Applications |
Abbreviated Journal |
P-Adic Num. |
Volume |
8 |
Issue |
1 |
Pages |
2-30 |
Keywords |
star products; non commutative spacetime; quantum groups |
Abstract |
We compute explicitly a star product on the Minkowski space whose Poisson bracket is quadratic. This star product corresponds to a deformation of the conformal spacetime, whose big cell is the Minkowski spacetime. The description of Minkowski space is made in the twistor formalism and the quantization follows by substituting the classical conformal group by a quantum group. |
Address |
[Cervantes, D.] IPN, CINVESTAV, Comp Sci Dept, Mexico City, DF, Mexico, Email: dalia@computacion.cs.cinvestav.mx; |
Corporate Author |
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Thesis |
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Publisher |
Maik Nauka-Interperiodica |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
2070-0466 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000410319300001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3295 |
Permanent link to this record |
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Author |
Cirigliano, V.; Jenkins, J.P.; Gonzalez-Alonso, M. |
Title |
Semileptonic decays of light quarks beyond the Standard Model |
Type |
Journal Article |
Year |
2010 |
Publication |
Nuclear Physics B |
Abbreviated Journal |
Nucl. Phys. B |
Volume |
830 |
Issue |
1-2 |
Pages |
95-115 |
Keywords |
Semileptonic decays; CKM unitarity; Effective theory; Beyond the Standard Model |
Abstract |
We describe non-standard contributions to semileptonic processes in a model independent way in terms of in SU(2)(L) x U(1)(Y) invariant effective lagrangian at the weak scale, front which we derive the low-energy effective lagrangian governing muon and beta decays. We find that the deviation from Cabibbo universality, Delta(CKM) equivalent to vertical bar V-ud vertical bar(2) + vertical bar V-us vertical bar(2) + vertical bar V-ub vertical bar(2) – 1, receives contributions from four effective operators. The phenomenological bound Delta(CKM) = (-1 +/- 6) x 10(-4) provides strong constraints on all four operators, corresponding to art effective scale Lambda > 11 TeV (90% CL). Depending on the operator, this constraint is at the same level or better then the Z pole observables. Conversely, precision electroweak constraints alone would allow universality violations as large as Delta(CKM) = -0.01 (90% CL). An observed Delta(CKM) not equal 0 at this level Could be explained in terms of a single four-fermion operator which is relatively poorly constrained by electroweak precision measurements. |
Address |
[Cirigliano, Vincenzo; Jenkins, James P.; Gonzalez-Alonso, Martin] Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA, Email: cirigliano@lanl.gov |
Corporate Author |
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Thesis |
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Publisher |
Elsevier Science Bv |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0550-3213 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
ISI:000275150000003 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ elepoucu @ |
Serial |
497 |
Permanent link to this record |
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Author |
ATLAS Collaboration (Aad, G. et al); Cabrera Urban, S.; Castillo Gimenez, V.; Costa, M.J.; Ferrer, A.; Fiorini, L.; Fuster, J.; Garcia, C.; Garcia Navarro, J.E.; Gonzalez de la Hoz, S.; Hernandez Jimenez, Y.; Higon-Rodriguez, E.; Irles Quiles, A.; Kaci, M.; Lacasta, C.; Lacuesta, V.R.; Marti-Garcia, S.; Miñano, M.; Mitsou, V.A.; Moles-Valls, R.; Moreno Llacer, M.; Oliver Garcia, E.; Perez Garcia-Estañ, M.T.; Romero Adam, E.; Ros, E.; Salt, J.; Sanchez Martinez, V.; Solans, C.A.; Soldevila, U.; Sanchez, J.; Torro Pastor, E.; Valero, A.; Valladolid Gallego, E.; Valls Ferrer, J.A.; Villaplana Perez, M.; Vos, M.; Wildauer, A. |
Title |
Measurement of the b-hadron production cross section using decays to D*(+)mu X- final states in pp collisions at root s=7 TeV with the ATLAS detector |
Type |
Journal Article |
Year |
2012 |
Publication |
Nuclear Physics B |
Abbreviated Journal |
Nucl. Phys. B |
Volume |
864 |
Issue |
3 |
Pages |
341-381 |
Keywords |
QCD; Flavour physics; B physics; Heavy quark production |
Abstract |
The b-hadron production cross section is measured with the ATLAS detector in pp collisions at root s = 7 TeV, using 3.3 pb(-1) of integrated luminosity, collected during the 2010 LHC run. The b-hadrons are selected by partially reconstructing D*(+)mu X- final states. Differential cross sections are measured as functions of the transverse momentum and pseudorapidity. The measured production cross section for a b-hadron with p(T) > 9 GeV and vertical bar eta vertical bar < 2.5 is 32.7 +/- 0.8(stat.)(-6.8)(+4.5)(syst.) μb, higher than the next-to-leading-order QCD predictions but consistent within the experimental and theoretical uncertainties. |
Address |
[Aad, G.; Ahles, F.; Barber, T.; Baroncelli, A.; Bernhard, R.; Bitenc, U.; Bruneliere, R.; Christov, A.; Consorti, V.; Fehling-Kaschek, M.; Flechl, M.; Glatzer, J.; Hartert, J.; Herten, G.; Horner, S.; Jansus, M.; Kollefrath, M.; Kononov, A. I.; Kuehn, S.; Lai, S.; Landgraf, U.; Lohwasser, K.; Ludwig, I.; Ludwig, J.; Lumb, D.; Mahboubi, K.; Mohr, W.; Nilsen, H.; Parzefall, U.; Rammensee, M.; Rave, T. C.; Rurikova, Z.; Schmidt, E.; Schumacher, M.; Siegert, F.; Stoerig, K.; Sundermann, J. E.; Temming, K. K.; Thoma, S.; Tsiskaridze, V.; Venturi, M.; Vivarelli, I.; von Radziewski, H.; Anh, T. Vu; Warsinsky, M.; Weiser, C.; Werner, M.; Wiik-Fuchs, L. A. M.; Winkelmann, S.; Xie, S.; Zimmermann, S.] Univ Freiburg, Fak Math & Phys, D-79106 Freiburg, Germany |
Corporate Author |
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Thesis |
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Publisher |
Elsevier Science Bv |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0550-3213 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000308049700001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1178 |
Permanent link to this record |