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Author Bordes, J.; Chan, H.M.; Tsou, S.T.
Title (up) delta(CP) for leptons and a new take on CP physics with the FSM Type Journal Article
Year 2021 Publication International Journal of Modern Physics A Abbreviated Journal Int. J. Mod. Phys. A
Volume 36 Issue Pages 2150236 - 22pp
Keywords Phenomenology beyond the Standard Model; framed Standard Model; leptonic CP violation; CP physics
Abstract A bonus of the framed Standard Model (FSM), constructed initially to explain the mass and mixing patterns of quarks and leptons, is a solution (without axions) of the strong CP problem by cancelling the theta-angle term theta(I) Tr(H-mu v H-mu v*) in coloura by a chiral transformation on a quark zero mode which is inherent in FSM, and produces thereby a CP-violating phase in the CKM matrix similar in size to what is observed.' Extending here to flavour, one finds that there are two terms proportional to Tr(G(mu v) G(mu v)*): (a) in the action from flavour instantons with unknown coefficient, say theta(I)', (b) induced by the above FSM solution to the strong CP-problem with therefore known coefficient theta(C)'. Both terms can be cancelled in the FSM by a chiral transformation on the lepton zero mode to give a Jarlskog invariant J' in the PMNS matrix for leptons of order 10(-2), as is hinted by the experiment. But if, as suggested in Ref. 2, the term theta(I)' is to be cancelled by a chiral transformation in the predicted hidden sector to solve the strong CP problem therein, leaving only the term theta(C)' to be cancelled by the chiral transformation on leptons, then the following prediction results: J' similar to -0.012 (delta(CP)'similar to (1.11)pi) which is (i) of the right order, (ii) of the right sign and (iii) in the range favoured by the present experiment. Together with the earlier result for quarks, this offers an attractive unified treatment of all known CP physics.
Address [Bordes, Jose] Univ Valencia, Ctr Mixto CSIC, Dept Fis Teor, Calle Dr Moliner 50, E-46100 Burjassot, Valencia, Spain, Email: jose.m.bordes@uv.es;
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 0217-751x ISBN Medium
Area Expedition Conference
Notes WOS:000732963000007 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5058
Permanent link to this record
 
 
Author NEXT Collaboration (Kekic, M. et al); Benlloch-Rodriguez, J.M.; Carcel, S.; Carrion, J.V.; Diaz, J.; Felkai, R.; Lopez-March, N.; Martin-Albo, J.; Martinez, A.; Martinez-Lema, G.; Martinez-Vara, M.; Muñoz Vidal, J.; Novella, P.; Palmeiro, B.; Querol, M.; Renner, J.; Romo-Luque, C.; Sorel, M.; Uson, A.; Yahlali, N.
Title (up) Demonstration of background rejection using deep convolutional neural networks in the NEXT experiment Type Journal Article
Year 2021 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 01 Issue 1 Pages 189 - 22pp
Keywords Dark Matter and Double Beta Decay (experiments)
Abstract Convolutional neural networks (CNNs) are widely used state-of-the-art computer vision tools that are becoming increasingly popular in high-energy physics. In this paper, we attempt to understand the potential of CNNs for event classification in the NEXT experiment, which will search for neutrinoless double-beta decay in Xe-136. To do so, we demonstrate the usage of CNNs for the identification of electron-positron pair production events, which exhibit a topology similar to that of a neutrinoless double-beta decay event. These events were produced in the NEXT-White high-pressure xenon TPC using 2.6 MeV gamma rays from a Th-228 calibration source. We train a network on Monte Carlo-simulated events and show that, by applying on-the-fly data augmentation, the network can be made robust against differences between simulation and data. The use of CNNs offers significant improvement in signal efficiency and background rejection when compared to previous non-CNN-based analyses.
Address [Hauptman, J.; Nygren, D. R.] Iowa State Univ, Dept Phys & Astron, 12 Phys Hall, Ames, IA 50011 USA, Email: marija.kekic@usc.es
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 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000616730800001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4729
Permanent link to this record
 
 
Author NEXT Collaboration (Haefner, J. et al); Carcel, S.; Carrion, J.V.; Lopez-March, N.; Martin-Albo, J.; Muñoz Vidal, J.; Novella, P.; Querol, M.; Romo-Luque, C.; Sorel, M.; Soto-Oton, J.; Uson, A.
Title (up) Demonstration of event position reconstruction based on diffusion in the NEXT-white detector Type Journal Article
Year 2024 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 84 Issue 5 Pages 518 - 13pp
Keywords
Abstract Noble element time projection chambers are a leading technology for rare event detection in physics, such as for dark matter and neutrinoless double beta decay searches. Time projection chambers typically assign event position in the drift direction using the relative timing of prompt scintillation and delayed charge collection signals, allowing for reconstruction of an absolute position in the drift direction. In this paper, alternate methods for assigning event drift distance via quantification of electron diffusion in a pure high pressure xenon gas time projection chamber are explored. Data from the NEXT-White detector demonstrate the ability to achieve good position assignment accuracy for both high- and low-energy events. Using point-like energy deposits from Kr-83m calibration electron captures (E similar to 45 keV), the position of origin of low-energy events is determined to 2 cm precision with bias <1 mm. A convolutional neural network approach is then used to quantify diffusion for longer tracks (E >= 1.5 MeV), from radiogenic electrons, yielding a precision of 3 cm on the event barycenter. The precision achieved with these methods indicates the feasibility energy calibrations of better than 1% FWHM at Q(beta beta) in pure xenon, as well as the potential for event fiducialization in large future detectors using an alternate method that does not rely on primary scintillation.
Address [Haefner, J.; Contreras, T.] Harvard Univ, Dept Phys, Cambridge, MA 02138 USA, Email: karen.navarro@uta.edu
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 1434-6044 ISBN Medium
Area Expedition Conference
Notes WOS:001228898800001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6138
Permanent link to this record
 
 
Author NEXT Collaboration (Novella, P. et al); Carcel, S.; Carrion, J.V.; Lopez, F.; Lopez-March, N.; Martin-Albo, J.; Muñoz Vidal, J.; Querol, M.; Romo-Luque, C.; Sorel, M.; Uson, A.
Title (up) Demonstration of neutrinoless double beta decay searches in gaseous xenon with NEXT Type Journal Article
Year 2023 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 09 Issue 9 Pages 190 - 35pp
Keywords Dark Matter and Double Beta Decay (experiments); Rare Decay
Abstract The NEXT experiment aims at the sensitive search of the neutrinoless double beta decay in Xe-136, using high-pressure gas electroluminescent time projection chambers. The NEXT-White detector is the first radiopure demonstrator of this technology, operated in the Laboratorio Subterr & aacute;neo de Canfranc. Achieving an energy resolution of 1% FWHM at 2.6 MeV and further background rejection by means of the topology of the reconstructed tracks, NEXT-White has been exploited beyond its original goals in order to perform a neu-trinoless double beta decay search. The analysis considers the combination of 271.6 days of Xe-136-enriched data and 208.9 days of 136Xe-depleted data. A detailed background mod-eling and measurement has been developed, ensuring the time stability of the radiogenic and cosmogenic contributions across both data samples. Limits to the neutrinoless mode are obtained in two alternative analyses: a background-model-dependent approach and a novel direct background-subtraction technique, offering results with small dependence on the background model assumptions. With a fiducial mass of only 3.50 +/- 0.01 kg of Xe-136-enriched xenon, 90% C.L. lower limits to the neutrinoless double beta decay are found in the T-1/2(0 nu) > 5.5x10(23) -1.3x10(24) yr range, depending on the method. The presented techniques stand as a pro of-of-concept for the searches to be implemented with larger NEXT detectors.
Address [Hauptman, J.] Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA, Email: pau.novella@ific.uv.es
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 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:001085073500001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5798
Permanent link to this record
 
 
Author NEXT Collaboration (Ferrario, P. et al); Benlloch-Rodriguez, J.M.; Kekic, M.; Renner, J.; Uson, A.; Alvarez, V.; Carcel, S.; Carrion, J.V.; Diaz, J.; Felkai, R.; Herrero, P.; Lopez-March, N.; Martinez-Lema, G.; Muñoz Vidal, J.; Novella, P.; Palmeiro, B.; Querol, M.; Romo-Luque, C.; Sorel, M.; Yahlali, N.
Title (up) Demonstration of the event identification capabilities of the NEXT-White detector Type Journal Article
Year 2019 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 10 Issue 10 Pages 052 - 20pp
Keywords Dark Matter and Double Beta Decay (experiments)
Abstract In experiments searching for neutrinoless double-beta decay, the possibility of identifying the two emitted electrons is a powerful tool in rejecting background events and therefore improving the overall sensitivity of the experiment. In this paper we present the first measurement of the efficiency of a cut based on the different event signatures of double and single electron tracks, using the data of the NEXT-White detector, the first detector of the NEXT experiment operating underground. Using a Th-228 calibration source to produce signal-like and background-like events with energies near 1.6 MeV, a signal efficiency of 71.6 +/- 1.5(stat) +/- 0.3(sys) % for a background acceptance of 20.6 +/- 0.4(stat) +/- 0.3(sys)% is found, in good agreement with Monte Carlo simulations. An extrapolation to the energy region of the neutrinoless double beta decay by means of Monte Carlo simulations is also carried out, and the results obtained show an improvement in background rejection over those obtained at lower energies.
Address [Hauptman, J.] Iowa State Univ, Dept Phys & Astron, 12 Phys Hall, Ames, IA 50011 USA, Email: paola.ferrario@dipc.org
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 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000509259700001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4260
Permanent link to this record
 
 
Author Albiol, F.; Corbi, A.; Albiol, A.
Title (up) 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 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 2169-3536 ISBN Medium
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
 
 
Author KM3NeT Collaboration (Ageron, M. et al); Calvo, D.; Coleiro, A.; Colomer, M.; Gozzini, S.R.; Hernandez-Rey, J.J.; Illuminati, G.; Khan Chowdhury, N.R.; Manczak, J.; Real, D.; Thakore, T.; Zornoza, J.D.; Zuñiga, J.
Title (up) Dependence of atmospheric muon flux on seawater depth measured with the first KM3NeT detection units Type Journal Article
Year 2020 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 80 Issue 2 Pages 99 - 11pp
Keywords
Abstract KM3NeT is a research infrastructure located in the Mediterranean Sea, that will consist of two deep-sea Cherenkov neutrino detectors. With one detector (ARCA), the KM3NeT Collaboration aims at identifying and studying TeV-PeV astrophysical neutrino sources. With the other detector (ORCA), the neutrino mass ordering will be determined by studying GeV-scale atmospheric neutrino oscillations. The first KM3NeT detection units were deployed at the Italian and French sites between 2015 and 2017. In this paper, a description of the detector is presented, together with a summary of the procedures used to calibrate the detector in-situ. Finally, the measurement of the atmospheric muon flux between 2232-3386 m seawater depth is obtained.
Address [Ageron, M.; Bertin, V.; Billault, M.; Brunner, J.; Busto, J.; Caillat, L.; Cosquer, A.; Coyle, P.; Domi, A.; Dornic, D.; Enzenhofer, A.; Henry, S.; Keller, P.; Lamare, P.; Laurence, J.; Lincetto, M.; Maggi, G.; Perrin-Terrin, M.; Quinn, L.; Royon, J.; Salvadori, I.; Tezier, D.; Theraube, S.; Zaborov, D.] Aix Marseille Univ, CPPM, CNRS, IN2P3, Marseille, France, Email: simone.biagi@infn.it;
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 1434-6044 ISBN Medium
Area Expedition Conference
Notes WOS:000514581600002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4302
Permanent link to this record
 
 
Author NEXT Collaboration (Ghosh, S. et al); Martin-Albo, J.; Carcel, S.; Carrion, J.V.; Diaz, J.; Felkai, R.; Lopez-March, N.; Martinez-Vara, M.; Martinez-Lema, G.; Muñoz Vidal, J.; Novella, P.; Palmeiro, B.; Querol, M.; Romo-Luque, C.; Sorel, M.; Uson, A.; Yahlali, N.
Title (up) Dependence of polytetrafluoroethylene reflectance on thickness at visible and ultraviolet wavelengths in air Type Journal Article
Year 2020 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.
Volume 15 Issue 11 Pages P11031 - 16pp
Keywords Detector design and construction technologies and materials; Double-beta decay detectors; Time projection Chambers (TPC)
Abstract Polytetrafluoroethylene (PTFE) is an excellent diffuse reflector widely used in light collection systems for particle physics experiments. However, the reflectance of PTFE is a function of its thickness. In this work, we investigate this dependence in air for light of wavelengths 260 nm and 450 nm using two complementary methods. We find that PTFE reflectance for thicknesses from 5 mm to 10 mm ranges from 92.5% to 94.5% at 450 nm, and from 90.0% to 92.0% at 260 nm We also see that the reflectance of PIFE of a given thickness can vary by as much as 2.7% within the same piece of material. Finally, we show that placing a specular reflector behind the PTFE can recover the loss of reflectance in the visible without introducing a specular component in the reflectance.
Address [Hauptman, J.] Iowa State Univ, Dept Phys & Astron, 12 Phys Hall, Ames, IA 50011 USA, Email: jhaefner@g.harvard.edu
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 1748-0221 ISBN Medium
Area Expedition Conference
Notes WOS:000595650800024 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4633
Permanent link to this record
 
 
Author Valdes-Cortez, C.; Ballester, F.; Vijande, J.; Gimenez, V.; Gimenez-Alventosa, V.; Perez-Calatayud, J.; Niatsetski, Y.; Andreo, P.
Title (up) Depth-dose measurement corrections for the surface electronic brachytherapy beams of an Esteya(R) unit: a Monte Carlo study Type Journal Article
Year 2020 Publication Physics in Medicine and Biology Abbreviated Journal Phys. Med. Biol.
Volume 65 Issue 24 Pages 245026 - 12pp
Keywords electronic brachytherapy; eBT; dosimetry; ionization chamber; Monte Carlo
Abstract Three different correction factors for measurements with the parallel-plate ionization chamber PTW T34013 on the Esteya electronic brachytherapy unit have been investigated. This chamber type is recommended by AAPM TG-253 for depth-dose measurements in the 69.5 kV x-ray beam generated by the Esteya unit. Monte Carlo simulations using the PENELOPE-2018 system were performed to determine the absorbed dose deposited in water and in the chamber sensitive volume at different depths with a Type A uncertainty smaller than 0.1%. Chamber-to-chamber differences have been explored performing measurements using three different chambers. The range of conical applicators available, from 10 to 30 mm in diameter, has been explored. Using a depth-independent global chamber perturbation correction factor without a shift of the effective point of measurement yielded differences between the absorbed dose to water and the corrected absorbed dose in the sensitive volume of the chamber of up to 1% and 0.6% for the 10 mm and 30 mm applicators, respectively. Calculations using a depth-dependent perturbation factor, including or excluding a shift of the effective point of measurement, resulted in depth-dose differences of about +/- 0.5% or less for both applicators. The smallest depth-dose differences were obtained when a shift of the effective point of measurement was implemented, being displaced 0.4 mm towards the center of the sensitive volume of the chamber. The correction factors were obtained with combined uncertainties of 0.4% (k = 2). Uncertainties due to chamber-to-chamber differences are found to be lower than 2%. The results emphasize the relevance of carrying out detailed Monte Carlo studies for each electronic brachytherapy device and ionization chamber used for its dosimetry.
Address [Valdes-Cortez, Christian; Ballester, Facundo; Vijande, Javier] Univ Valencia UV, Dept Fis Atom Mol & Nucl, Burjassot, Spain, Email: cvalcort@gmail.com
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:000618031500001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4708
Permanent link to this record
 
 
Author Yu, Q.X.; Pavao, R.; Debastiani, V.R.; Oset, E.
Title (up) Description of the Xic and Xib states as molecular states Type Journal Article
Year 2019 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 79 Issue 2 Pages 167 - 14pp
Keywords
Abstract In this work we study several c and b states dynamically generated from the meson-baryon interaction in coupled channels, using an extension of the local hidden gauge approach in the Bethe-Salpeter equation. These molecular states appear as poles of the scattering amplitudes, and several of them can be identified with the experimentally observed c states, including the c(2790), c(2930), c(2970), c(3055) and c(3080). Also, for the recently reported b(6227) state, we find two poles with masses and widths remarkably close to the experimental data, for both the JP=1/2- and JP=3/2- sectors.
Address [Yu, Q. X.] Beijing Normal Univ, Coll Nucl Sci & Technol, Beijing 100875, Peoples R China, Email: qixinyu@ific.uv.es;
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 1434-6044 ISBN Medium
Area Expedition Conference
Notes WOS:000459831800008 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3929
Permanent link to this record