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Author Zamiralov, V.S.; Ozpineci, A.; Erkol, G.
Title QCD sum rules for the coupling constants of vector mesons to octet baryons Type Journal Article
Year 2013 Publication Moscow University Physics Bulletin Abbreviated Journal Mosc. Univ. Phys. Bull.
Volume 68 Issue 3 Pages 205-209
Keywords quantum chromodynamics; sum rules; baryons; vector mesons; Borel interval
Abstract The QCD sum rules on the light cone proposed by Wang for the coupling constants of the rho meson are generalized to the vector mesons omega and phi and all octet baryons, the I >-hyperon included. A comparison with other results is given.
Address [Zamiralov, V. S.] Moscow MV Lomonosov State Univ, Skobeltsyn Inst Nucl Phys, Moscow 119991, Russia, Email: zamir@depni.sinp.msu.ru
Corporate Author Thesis
Publisher Allerton Press Inc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0027-1349 ISBN Medium
Area Expedition Conference
Notes WOS:000322139000004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1517
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Author n_TOF Collaboration (Gawlik, A. et al); Domingo-Pardo, C.; Tain, J.L.; Tarifeño-Saldivia, A.
Title Radiative Neutron Capture Cross-Section Measurement of Ge Isotopes at n_TOF CERN Facility and Its Importance for Stellar Nucleosynthesis Type Journal Article
Year 2021 Publication Acta Physica Polonica A Abbreviated Journal Acta Phys. Pol. A
Volume 139 Issue 4 Pages 383-388
Keywords n_TOF; neutron time-of-flight; neutron capture cross-section; MACS
Abstract This manuscript summarizes the results of radiative neutron capture cross-section measurements on two stable germanium isotopes, Ge-70 and Ge-73. Experiments were performed at the n_TOF facility at CERN via the time-of-flight technique, over a wide neutron energy range, for all stable germanium isotopes (70,72,73,74, and 76). Results for Ge-70 [Phys. Rev. C 100, 045804 (2019)] and Ge-73 [Phys. Lett. B 790, 458 (2019)] are already published. In the field of nuclear structure, such measurements allow to study excited levels close to the neutron binding energy and to obtain information on nuclear properties. In stellar nucleosynthesis research, neutron induced reactions on germanium are of importance for nucleosynthesis in the weak component of the slow neutron capture processes.
Address [Gawlik, A.; Andrzejewski, J.; Perkowski, J.] Univ Lodz, Lodz, Poland, Email: aleksandra.gawlik@uni.lodz.pl
Corporate Author Thesis
Publisher Polish Acad Sciences Inst Physics Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0587-4246 ISBN Medium
Area Expedition Conference
Notes WOS:000653413700004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4840
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Author Bernabeu, J.; Martinez-Vidal, F.
Title Time-Reversal Violation Type
Year 2015 Publication Annual Review of Nuclear and Particle Science Abbreviated Journal Annu. Rev. Nucl. Part. Sci.
Volume 65 Issue Pages 403-427
Keywords time reversal; CP violation; T-odd products; electric dipole moments; B mesons; K mesons; EPR entanglement
Abstract The violation of CP symmetry between matter and antimatter in the neutral K and B meson systems is well established, with a high degree of consistency between all available experimental measurements and with the Standard Model of particle physics. On the basis of the up-to-now-unbroken CPT symmetry, the violation of CP symmetry strongly suggests that the behavior of these particles under weak interactions must also be asymmetric under time reversal T. Many searches for T violation have been performed and proposed using different observables and experimental approaches. These include T-odd observables, such as triple products in weak decays, and genuine observables, such as permanent electric dipole moments of nondegenerate stationary states and the breaking of the reciprocity relation. We discuss the conceptual basis of the required exchange of initial and final states with unstable particles, using quantum entanglement and the decay as a filtering measurement, for the case of neutral B and K mesons. Using this method, the BaBar experiment at SLAC has clearly observed T violation in B mesons.
Address [Bernabeu, Jose; Martinez-Vidal, Fernando] Univ Valencia, CSIC, IFIC, E-46071 Valencia, Spain
Corporate Author Thesis
Publisher Annual Reviews Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0163-8998 ISBN Medium
Area Expedition Conference
Notes WOS:000363473100017 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 2430
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Author Sepehri, A.; Pincak, R.; Olmo, G.J.
Title M-theory, graphene-branes and superconducting wormholes Type Journal Article
Year 2017 Publication International Journal of Geometric Methods in Modern Physics Abbreviated Journal Int. J. Geom. Methods Mod. Phys.
Volume 14 Issue 11 Pages 1750167 - 32pp
Keywords M-theory; wormholes; graphene; superconductors
Abstract Exploiting an M-brane system whose structure and symmetries are inspired by those of graphene (what we call a graphene-brane), we propose here a similitude between two layers of graphene joined by a nanotube and wormholes scenarios in the brane world. By using the symmetries and mathematical properties of the M-brane system, we show here how to possibly increase its conductivity, to the point of making it as a superconductor. The questions of whether and under which condition this might point to the corresponding real graphene structures becoming superconducting are briefly outlined.
Address [Sepehri, Alireza] Shahid Bahonar Univ, Fac Phys, POB 76175, Kerman, Iran, Email: alireza.sepehri@uk.ac.ir;
Corporate Author Thesis
Publisher World Scientific Publ Co Pte Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0219-8878 ISBN Medium
Area Expedition Conference
Notes WOS:000413442500018 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3334
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Author n_TOF Collaboration (Patronis, N. et al); Babiano-Suarez, V.; Balibrea Correa, J.; Domingo-Pardo, C.; Ladarescu, I.; Lerendegui-Marco, J.
Title Status report of the n_TOF facility after the 2nd CERN long shutdown period Type Journal Article
Year 2023 Publication EPJ Techniques and Instrumentation Abbreviated Journal EPJ Tech. Instrum.
Volume 10 Issue 1 Pages 13 - 10pp
Keywords Neutron time of flight; Spallation target; Nuclear astrophysics; Neutron physics; Neutron induced fission; Neutron reactions
Abstract During the second long shutdown period of the CERN accelerator complex (LS2, 2019-2021), several upgrade activities took place at the nTOF facility. The most important have been the replacement of the spallation target with a next generation nitrogen-cooled lead target. Additionally, a new experimental area, at a very short distance from the target assembly (the NEAR Station) was established. In this paper, the core commissioning actions of the new installations are described. The improvement in the nTOF infrastructure was accompanied by several detector development projects. All these upgrade actions are discussed, focusing mostly on the future perspectives of the n_TOF facility. Furthermore, some indicative current and future measurements are briefly reported.
Address [Patronis, N.; Goula, S.; Eleme, Z.; Stamati, M. E.; Vagena, E.] Univ Ioannina, Ioannina, Greece, Email: nikolaos.patronis@cern.ch
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2195-7045 ISBN Medium
Area Expedition Conference
Notes WOS:001008786600001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5591
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Author Cases, R.; Ros, E.; Zuñiga, J.
Title Measuring radon concentration in air using a diffusion cloud chamber Type Journal Article
Year 2011 Publication American Journal of Physics Abbreviated Journal Am. J. Phys.
Volume 79 Issue 9 Pages 903-908
Keywords cloud chambers; diffusion; radiation effects; radon; student experiments
Abstract Radon concentration in air is a major concern in lung cancer studies. A traditional technique used to measure radon abundance is the charcoal canister method. We propose a novel technique using a diffusion cloud chamber. This technique is simpler and can easily be used for physics demonstrations for high school and university students.
Address [Cases, R; Ros, E; Zuniga, J] Univ Valencia, CSIC, IFIC, Valencia 22085, Spain, Email: ramon.cases@uv.es
Corporate Author Thesis
Publisher Amer Assoc Physics Teachers Amer Inst Physics Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0002-9505 ISBN Medium
Area Expedition Conference
Notes WOS:000294064300003 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ elepoucu @ Serial 724
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Author Candela-Juan, C.; Vijande, J.; Garcia-Martinez, T.; Niatsetski, Y.; Nauta, G.; Schuurman, J.; Ouhib, Z.; Ballester, F.; Perez-Calatayud, J.
Title Comparison and uncertainty evaluation of different calibration protocols and ionization chambers for low-energy surface brachytherapy dosimetry Type Journal Article
Year 2015 Publication Medical Physics Abbreviated Journal Med. Phys.
Volume 42 Issue 8 Pages 4954-4964
Keywords x-ray beams; electronic brachytherapy; surface applicators; dosimetry; uncertainty
Abstract Purpose: A surface electronic brachytherapy (EBT) device is in fact an x-ray source collimated with specific applicators. Low-energy (<100 kVp) x-ray beam dosimetry faces several challenges that need to be addressed. A number of calibration protocols have been published for x-ray beam dosimetry. The media in which measurements are performed are the fundamental difference between them. The aim of this study was to evaluate the surface dose rate of a low-energy x-ray source with small field applicators using different calibration standards and different small-volume ionization chambers, comparing the values and uncertainties of each methodology. Methods: The surface dose rate of the EBT unit Esteya (Elekta Brachytherapy, The Netherlands), a 69.5 kVp x-ray source with applicators of 10, 15, 20, 25, and 30 mm diameter, was evaluated using the AAPM TG-61 (based on air kerma) and International Atomic Energy Agency (IAEA) TRS-398 (based on absorbed dose to water) dosimetry protocols for low-energy photon beams. A plane parallel T34013 ionization chamber (PTW Freiburg, Germany) calibrated in terms of both absorbed dose to water and air kerma was used to compare the two dosimetry protocols. Another PTW chamber of the same model was used to evaluate the reproducibility between these chambers. Measurements were also performed with two different Exradin A20 (Standard Imaging, Inc., Middleton, WI) chambers calibrated in terms of air kerma. Results: Differences between surface dose rates measured in air and in water using the T34013 chamber range from 1.6% to 3.3%. No field size dependence has been observed. Differences are below 3.7% when measurements with the A20 and the T34013 chambers calibrated in air are compared. Estimated uncertainty (with coverage factor k = 1) for the T34013 chamber calibrated in water is 2.2%-2.4%, whereas it increases to 2.5% and 2.7% for the A20 and T34013 chambers calibrated in air, respectively. The output factors, measured with the PTW chambers, differ by less than 1.1% for any applicator size when compared to the output factors that were measured with the A20 chamber. Conclusions: Measurements using both dosimetric protocols are consistent, once the overall uncertainties are considered. There is also consistency between measurements performed with both chambers calibrated in air. Both the T34013 and A20 chambers have negligible stem effect. Any x-ray surface brachytherapy system, including Esteya, can be characterized using either one of these calibration protocols and ionization chambers. Having less correction factors, lower uncertainty, and based on measurements, performed in closer to clinical conditions, the TRS-398 protocol seems to be the preferred option.
Address [Candela-Juan, C.; Perez-Calatayud, J.] La Fe Univ, Dept Radiat Oncol, Valencia 46026, Spain, Email: ccanjuan@gmail.com
Corporate Author Thesis
Publisher Amer Assoc Physicists Medicine Amer Inst Physics Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0094-2405 ISBN Medium
Area Expedition Conference
Notes WOS:000358933000051 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2323
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Author Aguiar, P.; Rafecas, M.; Ortuño, J.E.; Kontaxakis, G.; Santos, A.; Pavia, J.; Rosetti, M.
Title Geometrical and Monte Carlo projectors in 3D PET reconstruction Type Journal Article
Year 2010 Publication Medical Physics Abbreviated Journal Med. Phys.
Volume 37 Issue 11 Pages 5691-5702
Keywords 3D PET; iterative reconstruction; list-mode reconstruction; ray-tracing techniques; Monte Carlo simulation; system response matrix
Abstract Purpose: In the present work, the authors compare geometrical and Monte Carlo projectors in detail. The geometrical projectors considered were the conventional geometrical Siddon ray-tracer (S-RT) and the orthogonal distance-based ray-tracer (OD-RT), based on computing the orthogonal distance from the center of image voxel to the line-of-response. A comparison of these geometrical projectors was performed using different point spread function (PSF) models. The Monte Carlo-based method under consideration involves an extensive model of the system response matrix based on Monte Carlo simulations and is computed off-line and stored on disk. Methods: Comparisons were performed using simulated and experimental data of the commercial small animal PET scanner rPET. Results: The results demonstrate that the orthogonal distance-based ray-tracer and Siddon ray-tracer using PSF image-space convolutions yield better images in terms of contrast and spatial resolution than those obtained after using the conventional method and the multiray-based S-RT. Furthermore, the Monte Carlo-based method yields slight improvements in terms of contrast and spatial resolution with respect to these geometrical projectors. Conclusions: The orthogonal distance-based ray-tracer and Siddon ray-tracer using PSF image-space convolutions represent satisfactory alternatives to factorizing the system matrix or to the conventional on-the-fly ray-tracing methods for list-mode reconstruction, where an extensive modeling based on Monte Carlo simulations is unfeasible.
Address [Aguiar, Pablo] Univ Santiago de Compostela, Dept Fis Particulas, Complexo Hosp Univ Santiago de Compostela, Fdn IDICHUS IDIS, Santiago De Compostela, Spain, Email: pablo.aguiar.fernandez@sergas.es
Corporate Author Thesis
Publisher Amer Assoc Physicists Medicine Amer Inst Physics Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0094-2405 ISBN Medium
Area Expedition Conference
Notes ISI:000283747600015 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ elepoucu @ Serial 338
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Author Real, D.; Calvo, D.; Diaz, A.; Alves Garre, S.; Carretero, V.; Sanchez Losa, A.; Salesa Greus, F.
Title An Ultra-Narrow Time Optical Pulse Emitter Based on a Laser: UNTOPEL Type Journal Article
Year 2023 Publication IEEE Transactions on Nuclear Science Abbreviated Journal IEEE Trans. Nucl. Sci.
Volume 70 Issue 10 Pages 2364-2372
Keywords Instrumentation electronics; neutrino telescope instrumentation; subnanosecond light source; time calibration instrument
Abstract Light sources that emit repetitive subnanosecond pulses are used in neutrino telescopes for time calibration. Optical pulses with an ultra-narrow (subnanosecond) width can replicate the light produced by neutrino interactions, and are an important calibration and test element. By measuring the time-of-flight of the light, it is possible to provide a relative time calibration for all the detector photomultipliers. This work presents the ultra-narrow time optical pulse emitter based on a laser (UNTOPEL), an instrument emitting ultra-short laser optical pulses with a duration of 500 ps, energies per pulse of four microjoules at a wavelength of 532 nm, and a timing precision of 400 ps. The UNTOPEL pulse intensity can be fine-tuned, which is a novelty and a significant advantage in those applications that need to illuminate light detectors located at different distances with the same light intensity. The UNTOPEL pulse intensity can be controlled remotely, allowing for its use in operating conditions where physical access is impossible or difficult. Moreover, it is easy to operate and can be easily controlled through an inter-integrated circuit bus. The UNTOPEL is a sound instrument used when subnanosecond pulses and variable energy emissions are needed.
Address [Real, Diego; Calvo, David; Garre, Sergio Alves; Carretero, Victor; Losa, Agustin Sanchez; Greus, FranciscoSalesa] Univ Valencia, IFIC Inst Fis Corpuscular, CSIC, Paterna 46980, Spain, Email: real@ific.uv.es
Corporate Author Thesis
Publisher Ieee-Inst Electrical Electronics Engineers Inc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0018-9499 ISBN Medium
Area Expedition Conference
Notes WOS:001098078200010 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 5795
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Author Millar, W.L. et al; Bañon Caballero, D.
Title High-Power Test of Two Prototype X-Band Accelerating Structures Based on SwissFEL Fabrication Technology Type Journal Article
Year 2023 Publication IEEE Transactions on Nuclear Science Abbreviated Journal IEEE Trans. Nucl. Sci.
Volume 70 Issue 1 Pages 1-19
Keywords Radio frequency; Life estimation; Temperature measurement; Wires; Electric breakdown; Brazing; Rendering (computer graphics); Acceleration; breakdown; high gradient; linear accelerator cavity (LINAC); radio frequency (RF); test facilities; vacuum arc; X-band
Abstract This article presents the design, construction, and high-power test of two $X$ -band radio frequency (RF) accelerating structures built as part of a collaboration between CERN and the Paul Scherrer Institute (PSI) for the compact linear collider (CLIC) study. The structures are a modified “tuning-free ” variant of an existing CERN design and were assembled using Swiss free electron laser (SwissFEL) production methods. The purpose of the study is two-fold. The first objective is to validate the RF properties and high-power performance of the tuning-free, vacuum brazed PSI technology. The second objective is to study the structures' high-gradient behavior to provide insight into the breakdown and conditioning phenomena as they apply to high-field devices in general. Low-power RF measurements showed that the structure field profiles were close to the design values, and both structures were conditioned to accelerating gradients in excess of 100 MV/m in CERN's high-gradient test facility. Measurements performed during the second structure test suggest that the breakdown rate (BDR) scales strongly with the accelerating gradient, with the best fit being a power law relation with an exponent of 31.14. In both cases, the test results indicate that stable, high-gradient operation is possible with tuning-free, vacuum brazed structures of this kind.
Address [Millar, William L. L.; Grudiev, Alexej; Wuensch, Walter; Lasheras, Nuria Catalan; McMonagle, Gerard; Volpi, Matteo; Paszkiewicz, Jan; Edwards, Amelia; Wegner, Rolf; Bursali, Hikmet; Woolley, Benjamin; Magazinik, Anastasiya; Syratchev, Igor; Vnuchenko, Anna; Pitman, Samantha; del Pozo Romano, Veronica; Caballero, David Banon] CERN, CH-1211 Geneva, Switzerland, Email: lee.millar@cern.ch
Corporate Author Thesis
Publisher Ieee-Inst Electrical Electronics Engineers Inc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0018-9499 ISBN Medium
Area Expedition Conference
Notes WOS:000920658600001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5471
Permanent link to this record