| Records |
| Author |
Aggarwal, N. et al; Figueroa, D.G. |
| Title |
Challenges and opportunities of gravitational-wave searches at MHz to GHz frequencies |
Type |
Journal Article |
| Year |
2021 |
Publication |
Living Reviews in Relativity |
Abbreviated Journal |
Living Rev. Relativ. |
| Volume |
24 |
Issue |
1 |
Pages |
4 - 74pp |
| Keywords |
Ultra-high-frequency gravitational waves; Cosmological gravitational waves; Gravitational wave detectors; Fundamental physics with gavitational waves |
| Abstract |
The first direct measurement of gravitational waves by the LIGO and Virgo collaborations has opened up new avenues to explore our Universe. This white paper outlines the challenges and gains expected in gravitational-wave searches at frequencies above the LIGO/Virgo band, with a particular focus on Ultra High-Frequency Gravitational Waves (UHF-GWs), covering the MHz to GHz range. The absence of known astrophysical sources in this frequency range provides a unique opportunity to discover physics beyond the Standard Model operating both in the early and late Universe, and we highlight some of the most promising gravitational sources. We review several detector concepts that have been proposed to take up this challenge, and compare their expected sensitivity with the signal strength predicted in various models. This report is the summary of the workshop “Challenges and opportunities of high-frequency gravitational wave detection” held at ICTP Trieste, Italy in October 2019, that set up the stage for the recently launched Ultra-High-Frequency Gravitational Wave (UHF-GW) initiative. |
| Address |
[Aggarwal, Nancy] Northwestern Univ, Dept Phys & Astron, Ctr Interdisciplinary Explorat & Res Astrophys CI, Ctr Fundamental Phys, Evanston, IL 60208 USA, Email: nancy.aggarwal@northwestern.edu; |
| Corporate Author |
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Thesis |
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| Publisher |
Springer Int Publ Ag |
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 |
|
Edition |
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ISSN  |
2367-3613 |
ISBN |
|
Medium |
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| Area |
|
Expedition |
|
Conference |
|
| Notes |
WOS:000727359500002 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
5074 |
| Permanent link to this record |
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| |
| Author |
Cai, Y.; Herrero-Garcia, J.; Schmidt, M.A.; Vicente, A.; Volkas, R.R. |
| Title |
From the Trees to the Forest: A Review of Radiative Neutrino Mass Models |
Type |
Journal Article |
| Year |
2017 |
Publication |
Frontiers in Physics |
Abbreviated Journal |
Front. Physics |
| Volume |
5 |
Issue |
|
Pages |
63 - 56pp |
| Keywords |
neutrino masses; lepton flavor violation; lepton number violation; beyond the standard model; effective field theory; model building; LHC; dark matter |
| Abstract |
A plausible explanation for the lightness of neutrino masses is that neutrinos are massless at tree level, with their mass (typically Majorana) being generated radiatively at one or more loops. The new couplings, together with the suppression coming from the loop factors, imply that the new degrees of freedom cannot be too heavy (they are typically at the TeV scale). Therefore, in these models there are no large mass hierarchies and they can be tested using different searches, making their detailed phenomenological study very appealing. In particular, the new particles can be searched for at colliders and generically induce signals in lepton-flavor and lepton-number violating processes (in the case of Majorana neutrinos), which are not independent from reproducing correctly the neutrino masses and mixings. The main focus of the review is on Majorana neutrinos. We order the allowed theory space from three different perspectives: (i) using an effective operator approach to lepton number violation, (ii) by the number of loops at which the Weinberg operator is generated, (iii) within a given loop order, by the possible irreducible topologies. We also discuss in more detail some popular radiative models which involve qualitatively different features, revisiting their most important phenomenological implications. Finally, we list some promising avenues to pursue. |
| Address |
[Cai, Yi] Sun Yat Sen Univ, Sch Phys, Guangzhou, Guangdong, Peoples R China, Email: juan.herrero-garcia@coepp.org.au; |
| Corporate Author |
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Thesis |
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| Publisher |
Frontiers Research Foundation |
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 |
|
Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
|
Edition |
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| ISSN |
2296-424x |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
WOS:000416908800001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
3393 |
| Permanent link to this record |
| |
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| |
| Author |
Vicente, A. |
| Title |
Higgs Lepton Flavor Violating Decays in Two Higgs Doublet Models |
Type |
Journal Article |
| Year |
2019 |
Publication |
Frontiers in Physics |
Abbreviated Journal |
Front. Physics |
| Volume |
7 |
Issue |
|
Pages |
174 - 13pp |
| Keywords |
Higgs boson; lepton flavor violating decays; beyond the standard model; two Higgs doublet models; effective field theory |
| Abstract |
The discovery of a non-zero rate for a lepton flavor violating decay mode of the Higgs boson would definitely be an indication of New Physics. We review the prospects for such signal in Two Higgs Doublet Models, in particular for Higgs boson decays into tau μfinal states. We will show that this scenario contains all the necessary ingredients to provide large flavor violating rates and still be compatible with the stringent limits from direct searches and low-energy flavor experiments. |
| Address |
[Vicente, Avelino] Univ Valencia, CSIC, Inst Fis Corpuscular, Valencia, Spain, Email: avelino.vicente@ific.uv.es |
| Corporate Author |
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Thesis |
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| Publisher |
Frontiers Media Sa |
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 |
|
Series Title |
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Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2296-424x |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
WOS:000498568200001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
no |
| Call Number |
IFIC @ pastor @ |
Serial |
4206 |
| Permanent link to this record |
| |
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| |
| Author |
Asai, M.; Cortes-Giraldo, M.A.; Gimenez-Alventosa, V.; Gimenez, V.; Salvat, F. |
| Title |
The PENELOPE Physics Models and Transport Mechanics. Implementation into Geant4 |
Type |
Journal Article |
| Year |
2021 |
Publication |
Frontiers in Physics |
Abbreviated Journal |
Front. Physics |
| Volume |
9 |
Issue |
|
Pages |
738735 - 20pp |
| Keywords |
coupled electron-photon transport; Monte Carlo simulation; PENELOPE code system; random-hinge method; Geant4 toolkit |
| Abstract |
A translation of the penelope physics subroutines to C++, designed as an extension of the Geant4 toolkit, is presented. The Fortran code system penelope performs Monte Carlo simulation of coupled electron-photon transport in arbitrary materials for a wide energy range, nominally from 50 eV up to 1 GeV. Penelope implements the most reliable interaction models that are currently available, limited only by the required generality of the code. In addition, the transport of electrons and positrons is simulated by means of an elaborate class II scheme in which hard interactions (involving deflection angles or energy transfers larger than pre-defined cutoffs) are simulated from the associated restricted differential cross sections. After a brief description of the interaction models adopted for photons and electrons/positrons, we describe the details of the class-II algorithm used for tracking electrons and positrons. The C++ classes are adapted to the specific code structure of Geant4. They provide a complete description of the interactions and transport mechanics of electrons/positrons and photons in arbitrary materials, which can be activated from the G4ProcessManager to produce simulation results equivalent to those from the original penelope programs. The combined code, named PenG4, benefits from the multi-threading capabilities and advanced geometry and statistical tools of Geant4. |
| Address |
[Asai, Makoto] SLAC Natl Accelerator Lab, Menlo Pk, CA USA, Email: miancortes@us.es; |
| Corporate Author |
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Thesis |
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| Publisher |
Frontiers Media Sa |
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 |
|
Series Issue |
|
Edition |
|
| ISSN |
2296-424x |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
WOS:000742889400001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
5080 |
| Permanent link to this record |
| |
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| |
| Author |
Martinez-Reviriego, P.; Esperante, D.; Grudiev, A.; Gimeno, B.; Blanch, C.; Gonzalez-Iglesias, D.; Fuster-Martinez, N.; Martin-Luna, P.; Martinez, E.; Menendez, A.; Fuster, J. |
| Title |
Dielectric assist accelerating structures for compact linear accelerators of low energy particles in hadrontherapy treatments |
Type |
Journal Article |
| Year |
2024 |
Publication |
Frontiers in Physics |
Abbreviated Journal |
Front. Physics |
| Volume |
12 |
Issue |
|
Pages |
1345237 - 12pp |
| Keywords |
dielectric assist accelerating (DAA) structures; radio frequency (RF); LINAC; hadrontherapy; standing wave |
| Abstract |
Dielectric Assist Accelerating (DAA) structures based on ultralow-loss ceramic are being studied as an alternative to conventional disk-loaded copper cavities. This accelerating structure consists of dielectric disks with irises arranged periodically in metallic structures working under the TM02-pi mode. In this paper, the numerical design of an S-band DAA structure for low beta particles, such as protons or carbon ions used for Hadrontherapy treatments, is shown. Four dielectric materials with different permittivity and loss tangent are studied as well as different particle velocities. Through optimization, a design that concentrates most of the RF power in the vacuum space near the beam axis is obtained, leading to a significant reduction of power loss on the metallic walls. This allows to fabricate cavities with an extremely high quality factor, over 100,000, and shunt impedance over 300 M omega/m at room temperature. During the numerical study, the design optimization has been improved by adjusting some of the cell parameters in order to both increase the shunt impedance and reduce the peak electric field in certain locations of the cavity, which can lead to instabilities in its normal functioning. |
| Address |
[Martinez-Reviriego, Pablo; Esperante, Daniel; Gimeno, Benito; Blanch, Cesar; Gonzalez-Iglesias, Daniel; Fuster-Martinez, Nuria; Martin-Luna, Pablo; Martinez, Eduardo; Menendez, Abraham; Fuster, Juan] CSIC Univ Valencia, Inst Fis Corpuscular IFIC, Paterna, Spain, Email: pablo.martinez.reviriego@ific.uv.es |
| Corporate Author |
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Thesis |
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| Publisher |
Frontiers Media Sa |
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 |
|
Edition |
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| ISSN |
2296-424x |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
WOS:001162373700001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
5953 |
| Permanent link to this record |
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| |
| Author |
Llosa, G.; Trovato, M.; Barrio, J.; Etxebeste, A.; Muñoz, E.; Lacasta, C.; Oliver, J.F.; Rafecas, M.; Solaz, C.; Solevi, P. |
| Title |
First Images of a Three-layer compton Telescope prototype for Treatment Monitoring in hadron Therapy |
Type |
Journal Article |
| Year |
2016 |
Publication |
Frontiers in Oncology |
Abbreviated Journal |
Front. Oncol. |
| Volume |
6 |
Issue |
|
Pages |
14 - 6pp |
| Keywords |
Compton camera; Compton telescope; hadron therapy; treatment monitoring; LaBr3 |
| Abstract |
A Compton telescope for dose monitoring in hadron therapy is under development at IFIC. The system consists of three layers of LaBr3 crystals coupled to silicon photomulti-plier arrays. Na-22 sources have been successfully imaged reconstructing the data with an ML-EM code. Calibration and temperature stabilization are necessary for the prototype operation at low coincidence rates. A spatial resolution of 7.8 mm FWHM has been obtained in the first imaging tests. |
| Address |
[Llosa, Gabriela; Trovato, Marco; Barrio, John; Etxebeste, Ane; Munoz, Enrique; Lacasta, Carlos; Oliver, Josep F.; Rafecas, Magdalena; Solaz, Carles; Solevi, Paola] Inst Fis Corpuscular IFIC CSIC UVEG, Valencia, Spain, Email: gabriela.llosa@ific.uv.es |
| Corporate Author |
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Thesis |
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| Publisher |
Frontiers Media Sa |
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 |
2234-943x |
ISBN |
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Medium |
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| Area |
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Expedition |
|
Conference |
|
| Notes |
WOS:000369799800001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
no |
| Call Number |
IFIC @ elepoucu @ |
Serial |
2785 |
| Permanent link to this record |
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| |
| Author |
Simpson, F.; Jimenez, R.; Pena-Garay, C.; Verde, L. |
| Title |
Dark energy from the motions of neutrinos |
Type |
Journal Article |
| Year |
2018 |
Publication |
Physics of the Dark Universe |
Abbreviated Journal |
Phys. Dark Universe |
| Volume |
20 |
Issue |
|
Pages |
72-77 |
| Keywords |
Neutrinos; Dark energy; Interactions in the dark sector |
| Abstract |
Ordinarily, a scalar field may only play the role of dark energy if it possesses a potential that is either extraordinarily flat or extremely fine-tuned. Here we demonstrate that these restrictions are lifted when the scalar field undergoes persistent energy exchange with another fluid. In this scenario, the field is prevented from reversing its direction of motion, and instead may come to rest while displaced from the local minimum of its potential. Therefore almost any scalar potential is capable of initiating a prolonged phase of cosmic acceleration. If the rate of energy transfer is modulated via a derivative coupling, the field undergoes a rapid process of freezing, after which the field's equation of state mimicks that of a cosmological constant. We present a physically motivated realisation in the form of a neutrino-majoron coupling, which avoids the dynamical instabilities associated with mass-varying neutrino models. Finally we discuss possible means by which this model could be experimentally verified. |
| Address |
[Simpson, Fergus; Jimenez, Raul; Verde, Licia] Univ Barcelona, UB IEEC, ICC, Marti i Franques 1, E-08028 Barcelona 08028, Spain, Email: feigus2@icc.ub.edu; |
| 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 |
2212-6864 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
|
| Notes |
WOS:000433904300009 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
3599 |
| Permanent link to this record |
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| Author |
Jay, G.; Arnault, P.; Debbasch, F. |
| Title |
Dirac quantum walks with conserved angular momentum |
Type |
Journal Article |
| Year |
2021 |
Publication |
Quantum Studies-Mathematics and Foundations |
Abbreviated Journal |
Quantum Stud. Math. Found. |
| Volume |
8 |
Issue |
|
Pages |
419-430 |
| Keywords |
Quantum walks; Quantum simulation; Lattice field theory |
| Abstract |
A quantum walk (QW) simulating the flat (1+2)D Dirac equation on a spatial polar grid is constructed. Because fermions are represented by spinors, which do not constitute a representation of the rotation group SO(3), but rather of its double cover SU(2), the QW can only be defined globally on an extended spacetime where the polar angle extends from 0 to 4 pi. The coupling of the QW with arbitrary electromagnetic fields is also presented. Finally, the cylindrical relativistic Landau levels of the Dirac equation are computed explicitly and simulated by the QW. |
| Address |
[Jay, Gareth] Univ Western Australia, Phys Dept, Perth, WA 6009, Australia, Email: gareth.jay@uwa.edu.au; |
| Corporate Author |
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Thesis |
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| Publisher |
Springer |
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 |
|
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 |
2196-5609 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
|
| Notes |
WOS:000697709700001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
4975 |
| Permanent link to this record |
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| |
| Author |
Albiol, F.; Corbi, A.; Albiol, A. |
| Title |
Densitometric Radiographic Imaging With Contour Sensors |
Type |
Journal Article |
| Year |
2019 |
Publication |
IEEE Access |
Abbreviated Journal |
IEEE Access |
| Volume |
7 |
Issue |
|
Pages |
18902-18914 |
| Keywords |
Conventional X-ray imaging; contour data; densitometric images; dynamic range; depth information |
| Abstract |
We present the technical/physical foundations of a new imaging technique that combines ordinary radiographic information (generated by conventional X-ray settings) with the patient's volume to derive densitometric images. Traditionally, these images provide quantitative information about tissues densities. In our approach, they graphically enhance either soft or bony regions. After measuring the patient's volume with contour recognition devices, the physical traversed lengths within it (as the Roentgen beam intersects the patient) are calculated and pixel-wise associated with the original radiograph (X). In order to derive this map of lengths (L), the camera equations of the X-ray system and the contour sensor are determined. The patient's surface is also translated to the point-of-view of the X-ray beam and all its entrance/exit points are sought with the help of ray-casting methods. The derived L is applied to X as a physical operation (subtraction), obtaining soft tissue-(D-S) or bone-enhanced (D'(B)) figures. In the D-S type, the contained graphical information can be linearly mapped to the average electronic density (traversed by the X-ray beam). This feature represents an interesting proof-of-concept of associating density data to radiographs, but most important, their intensity histogram is objectively compressed, i.e., the dynamic range is more shrunk (compared against the corresponding X). This leads to other advantages: improvement in the visibility of border/edge areas (high gradient), extended manual window level/width manipulations during screening, and immediate correction of underexposed X instances. In the D-B' type, high-density elements are highlighted and easier to discern. All these results can be achieved with low-energy beam exposures, saving costs and dose. Future work will deepen this clinical side of our research. In contrast with other image-based modifiers, the proposed method is grounded on the measurement of a physical entity: the span of the X-ray beam within a body while undertaking a radiographic examination. |
| Address |
[Albiol, Francisco; Corbi, Alberto] CSIC, Inst Fis Corpuscular, Paterna 46980, Spain, Email: kiko@ific.uv.es |
| Corporate Author |
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Thesis |
|
| Publisher |
Ieee-Inst Electrical Electronics Engineers Inc |
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 |
2169-3536 |
ISBN |
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Medium |
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| Area |
|
Expedition |
|
Conference |
|
| Notes |
WOS:000459591800001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
no |
| Call Number |
IFIC @ pastor @ |
Serial |
3920 |
| Permanent link to this record |
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| |
| Author |
Pierre Auger Collaboration (Aab, A. et al); Pastor, S. |
| Title |
A targeted search for point sources of EeV neutrons |
Type |
Journal Article |
| Year |
2014 |
Publication |
Astrophysical Journal Letters |
Abbreviated Journal |
Astrophys. J. Lett. |
| Volume |
789 |
Issue |
2 |
Pages |
L34 - 7pp |
| Keywords |
cosmic rays; Galaxy: disk; methods: data analysis |
| Abstract |
A flux of neutrons from an astrophysical source in the Galaxy can be detected in the Pierre Auger Observatory as an excess of cosmic-ray air showers arriving from the direction of the source. To avoid the statistical penalty for making many trials, classes of objects are tested in combinations as nine “target sets,” in addition to the search for a neutron flux from the Galactic center or from the Galactic plane. Within a target set, each candidate source is weighted in proportion to its electromagnetic flux, its exposure to the Auger Observatory, and its flux attenuation factor due to neutron decay. These searches do not find evidence for a neutron flux from any class of candidate sources. Tabulated results give the combined p-value for each class, with and without the weights, and also the flux upper limit for the most significant candidate source within each class. These limits on fluxes of neutrons significantly constrain models of EeV proton emission from non-transient discrete sources in the Galaxy. |
| Address |
[Aab, A.; Buchholz, P.; Erfani, M.; Frohlich, U.; Heimann, P.; Homola, P.; Niechciol, M.; Ochilo, L.; Risse, M.; Yushkov, A.; Ziolkowski, M.] Univ Siegen, D-57068 Siegen, Germany |
| 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 |
2041-8205 |
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:000339876800009 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
1885 |
| Permanent link to this record |
