Influencia de los componentes parásitos en el análisis y diseño de inversores resonantes paralelo para aplicaciones de calentamiento por inducción

La aparición de nuevos dispositivos semiconductores de conmutación cada vez másrápidos y capaces junto con el uso de modernas técnicas de control ha permitido la mejora deparámetros básicos de los equipos industriales como son la fiabilidad, la seguridad y elrendimiento. En calentamiento por inducción, el uso de estos nuevos dispositivos ha permitidoademás el aumento de la potencia y frecuencia de funcionamiento con lo que se han evidenciadolos efectos perjudiciales que provocan las diversas magnitudes parásitas que aparecen en loscomponentes y conexiones de estos equipos. El presente trabajo se basa en el estudio de estosefectos y en el análisis y diseño de circuitos capaces de resolver los problemas que estos planteanen inversores resonantes paralelo para aplicaciones de calentamiento por inducción con el objetode aumentar su rendimiento y fiabilidad trabajando a altas frecuencias.En la actualidad la gama de frecuencias en las aplicaciones de calentamiento porinducción está cubierta mediante convertidores cuyas tecnologías han sido elegidas optimizandocriterios de coste, fiabilidad y rendimiento. A partir de algunas decenas de kilohercios elrendimiento y la fiabilidad de los convertidores con transistores IGBT baja haciendo aconsejablecubrir las aplicaciones en estas frecuencias con convertidores con transistores MOS.A continuación se muestra la situación que se puede alcanzar incorporando las técnicasque aquí se presentan. La gama de frecuencias de los convertidores con transistores IGBT seextiende hasta alcanzar los 100 kHz con lo que pueden sustituir en este segmento de frecuenciasa los transistores MOS reduciendo consecuentemente el coste del equipo. De un modo análogose incrementará la frecuencia de trabajo de los convertidores con transistor MOS que podránsustituir en la práctica totalidad de aplicaciones a los generadores con tubo electrónico.Seguidamente se hace un breve resumen de los contenidos de cada unos de los capítulosde esta memoria.El primer capítulo muestra una introducción al calentamiento por inducción dando unarelación de las necesidades de este sector industrial y las soluciones aportadas por la ElectrónicaIndustrial en el transcurso de los últimos años.Los equipos generadores utilizados en caldeo por inducción tienen como punto comúnque la carga es un circuito resonante. En el segundo capítulo se aborda el análisis y condicionesde carga de las distintas configuraciones resonantes paralelo así como la caracterización de loscomponentes básicos de los convertidores y el estudio de sus estructuras topológicas dando unaespecial atención a los circuitos inversores con carga resonante paralelo.Una vez caracterizados los circuitos de salida y definidas las topologías del convertidor,en el tercer capítulo se estudian los procesos de conmutación de los dispositivos conmutadoresen inversores con carga resonante paralelo para diferentes condiciones de funcionamiento. Estosprocesos se pueden mejorar con el uso de redes de ayuda a la conmutación cuyo funcionamientotambién será analizado. En este capítulo se introducen las técnicas del disparo de losconmutadores del inversor para conseguir conmutaciones suaves que reduzcan las pérdidas deconmutación permitiendo así la posibilidad de aumentar tanto la potencia como la frecuencia delconvertidor. El estudio de este sistema de control se hará en el cuarto capítulo y se completarámediante su modelización y estudio dinámico.En el capítulo quinto se estudiará el funcionamiento del inversor resonante paralelo encondiciones de cortocircuito exponiéndose los problemas que implica esta circunstancia y laefectividad de las soluciones propuestas.Finalmente, en los dos últimos capítulos se mostrarán los resultados experimentalesobtenidos sobre generadores con inversor resonante paralelo de alta frecuencia contransistores IGBT y MOS para calentamiento por inducción y la relación de aportaciones deeste trabajo.The appearance of new devices more and more fast and capable switchingsemiconductors together with the use of modern control techniques has allowed the improvementof basic parameters of the industrial teams as they are the reliability, the security and theefficiency. In induction heating, the use of these new devices has allowed the increase of thepower and operation frequency. With this, the harmful effects that cause the parasitic magnitudesin the components and connections appears. The present work is based on the study of theseeffects and in the analysis and design of circuits able to solve the problems in parallel resonantinverters for induction heating applications in order to increasing its efficiency and reliabilityworking at high frequencies.Subsequently a brief summary of the contents is made of each one of the chapters of thismemory. The first chapter shows an introduction to the induction heating giving a relationship ofthe necessities of this industrial sector and the solutions contributed by the Industrial Electronicsin the course of the last years. In the second chapter it is approached the analysis and conditionsof load of the different configurations of the parallel resonant circuit as well as thecharacterisation of the basic components of the converters and the study of their structures. In thethird chapter the processes of commutation of the devices switches are studied in inverters withparallel resonant load for different operation conditions. The soft commutations techniques areintroduced to reduce the commutation losses allowing this way the possibility to increase asmuch the power as the frequency of the converter. The study of this control system will be madein the fourth chapter and it will be completed by means of its modelización and dynamic study.In the chapter fifth the parallel resonant investor's operation will be studied under short circuitconditions. Finally, in the last two chapters the experimental results obtained on generatorswith parallel resonant inverters of high frequency for induction heating will be shown

¿Qué es la psicología para los estudiantes españoles de educación a distancia?

Se aplicó a los estudiantes de Psicología de la Universidad Nacional de Educación a Distancia en España (UNED) una modificación de la escala estandarizada por Thiriat (1981) y que ha sido utilizada (con más o menos cambios) en casi la totalidad de los trabajos de este tipo. En la encuesta se indaga sobre el autor, la obra y el fenómeno que considerasen como los más destacados de nuestra disciplina. También se les pedía que eligiesen entre varias definiciones de psicología y de diferentes conceptos relevantes como el pensamiento, la inteligencia o la mente. Por último, se les requería una valoración de diferentes aspectos de la psicología y de la propia psicología en su conjunto en comparación con otros campos del saber. Se concluye comparando los resultados obtenidos en este trabajo con otros similares realizados con otras poblacione

Zero Ripple Current with Coupled Inductors in Continuous Conduction Mode under PWM Signals

This article presents a generalized analysis to explain current ripple of an m windings coupled inductor with a given coupling factor k ij for each pair of windings and then studies more in detail its use in the continuous conduction mode and with pulsewidth modulated signals. To determine the current ripple, a generalized expression of the equivalent inductance of each winding is calculated, including the influence of voltage unbalance. In the ideal case, the equivalent inductance shows that the current ripple can only become m times smaller than that with uncoupled inductors. But in the unbalanced case, some divergences of the equivalent inductance appear that are responsible for zero ripple current. The proposed generalized expressions of the equivalent inductance also describe the current ripple of the new appearing intervals due to out-of-phase signals. An easy to design condition is proposed that achieves zero current ripple in all windings but one. Experimental results are provided that validate the presented theoretical expressions under the given conditions

Design of Zero-Ripple-Current Coupled Inductors with PWM signals in Continuous Conduction Mode

Coupled inductors are widely used in multiple outputs and interleaved dc-dc converters. Also filters often use coupled inductors as their inductive part. A generalized design procedure is proposed in this article focused on current ripple minimization and applicable to coupled inductors exposed to pulsewidth modulation signals and in continuous conduction mode. The design provides a very large inductance for all windings but one. Compared to other designs, it adapts to the existing magnetic properties of the magnetic device changing only the inductance ratio, simplifying the design and manufacturing process. It is based on the equivalent inductance value and its divergences. The only assumption applied is that the coupling coefficient among all windings is the same, which is an acceptable approximation in many magnetic core architectures. The theoretical results are experimentally verified. Not only almost zero ripple current is achieved, but also mass and volume is reduced compared to noncoupled inductors. This is an additional advantage of coupled inductors in mass and volume critical applications such as aerospace

The electronics of the energy plane of the NEXT-White detector

[EN] This paper describes the electronics of NEXT-White (NEW) detector PMT plane, a high pressure xenon TPC with electroluminescent amplification (HPXe-EL) currently operating at the Laboratorio Subterraneo de Canfranc (LSC) in Huesca, Spain. In NEXT-White the energy of the event is measured by a plane of photomultipliers (PMTs) located behind a transparent cathode. The PMTs are Hamamatsu R11410-10 chosen due to their low radioactivity. The electronics have been designed and implemented to fulfill strict requirements: an overall energy resolution below 1% and a radiopurity budget of 20 mBq unit(-1) in the chain of Bi-214. All the components and materials have been carefully screened to assure a low radioactivity level and at the same time meet the required front-end electronics specifications. In order to reduce low frequency noise effects and enhance detector safety a grounded cathode connection has been used for the PMTs. This implies an AC-coupled readout and baseline variations in the PMT signals. A detailed description of the electronics and a novel approach based on a digital baseline restoration to obtain a linear response and handle AC coupling effects is presented. The final PMT channel design has been characterized with linearity better than 0.4% and noise below 0.4mV.We acknowledge support from the following agencies and institutions: the European Research Council (ERC), Spain under the Advanced Grant 339787-NEXT; the Ministerio de Economia y Competitividad of Spain under grants FIS2014-53371-C04, the Severo Ochoa Program, Spain SEV-2014-0398 and the Maria de Maetzu Program, Spain MDM-2016-0692; the GVA of Spain under grants PROMETEO/2016/120 and SEJI/2017/011; the Portuguese FCT and FEDER, Spain through the program COMPETE, projects PTDC/FIS-NUC/2525/2014 and UID/FIS/04559/2013; the U.S. Department of Energy under contracts number DE-AC02-07CH11359 (Fermi National Accelerator Laboratory), DE-FG02-13ER42020 (Texas A&M) and de-sc0017721 (University of Texas at Arlington); and the University of Texas at Arlington. We acknowledge partial support from the European Union Horizon 2020 research and innovation programme, Spain under the Marie Sklodowska-Curie grant agreements No. 690575 and 674896. We also warmly acknowledge the Laboratorio Nazionale di Gran Sasso (LNGS) and the Dark Side collaboration for their help with TPB coating of various parts of the NEXT-White TPC. Finally, we are grateful to the Laboratorio Subterraneo de Canfranc for hosting and supporting the NEXT experiment.Álvarez-Puerta, V.; Herrero Bosch, V.; Esteve Bosch, R.; Laing, A.; Rodriguez-Samaniego, J.; Querol-Segura, M.; Monrabal, F.... (2019). The electronics of the energy plane of the NEXT-White detector. Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment. 917:68-76. https://doi.org/10.1016/j.nima.2018.11.126S687691

Enhanced asymmetrical modulation for half-bridge series resonant inverters in induction heating applications

This paper presents a method that improves the reliability of half-bridge (HB) series resonant inverters (SRI) for high-frequency induction heating applications. Many industrial processes, like induction heat treatments, are very repetitive. This cyclical operation represents a strong limitation of the inverter's reliability, mainly due to the accelerated stress of the power semiconductors. This method consists in an enhanced asymmetrical pulse width modulation (EAPWM) that allows distributing the losses across the components, thereby reducing the cyclic increase in junction temperature of the power devices, and thus achieves a reliability that is more than twice as high as that achieved using traditional modulation methods. The work methodology includes a theoretical study of the HB inverter and a complete analysis of losses. The presented design rules have been used to implement a 25 kW, 100 kHz inverter. The use of silicon carbide (SiC) MOSFET transistors allows reaching an efficiency greater than 99%. The analytical results obtained have been experimentally validated by testing the inverter on an induction heating test bench

Low-diffusion Xe-He gas mixtures for rare-event detection: electroluminescence yield

[EN] High pressure xenon Time Projection Chambers (TPC) based on secondary scintillation (electroluminescence) signal amplification are being proposed for rare event detection such as directional dark matter, double electron capture and double beta decay detection. The discrimination of the rare event through the topological signature of primary ionisation trails is a major asset for this type of TPC when compared to single liquid or double-phase TPCs, limited mainly by the high electron diffusion in pure xenon. Helium admixtures with xenon can be an attractive solution to reduce the electron diffu- sion significantly, improving the discrimination efficiency of these optical TPCs. We have measured the electroluminescence (EL) yield of Xe-He mixtures, in the range of 0 to 30% He and demonstrated the small impact on the EL yield of the addition of helium to pure xenon. For a typical reduced electric field of 2.5 kV/cm/bar in the EL region, the EL yield is lowered by similar to 2%, 3%, 6% and 10% for 10%, 15%, 20% and 30% of helium concentration, respectively. This decrease is less than what has been obtained from the most recent simulation framework in the literature. The impact of the addition of helium on EL statistical fluctuations is negligible, within the experimental uncertainties. The present results are an important benchmark for the simulation tools to be applied to future optical TPCs based on Xe-He mixtures.The NEXT Collaboration acknowledges support from the following agencies and institutions: the European Research Council (ERC) under the Advanced Grant 339787-NEXT; the European Union's Framework Programme for Research and Innovation Horizon 2020 (2014-2020) under the Marie Sklodowska-Curie Grant Agreements No. 674896, 690575 and 740055; the Ministerio de Economa y Competitividad of Spain under grants FIS2014-53371-C04, RTI2018-095979, the Severo Ochoa Program SEV-2014-0398 and the Mara de Maetzu Program MDM-2016-0692; the GVA of Spain under grants PROMETEO/2016/120 and SEJI/2017/011; the Portuguese FCT under project PTDC/FIS-NUC/2525/2014, under project UID/FIS/04559/2013 to fund the activities of LIBPhys, and under grants PD/BD/105921/2014, SFRH/BPD/109180/2015; the U.S. Department of Energy under contracts number DEAC02-06CH11357 (Argonne National Laboratory), DE-AC0207CH11359 (Fermi National Accelerator Laboratory), DE-FG02-13ER42020 (Texas A& M) and DE-SC0019223/DESC0019054 (University of Texas at Arlington); and the University of Texas at Arlington. DGD acknowledges Ramon y Cajal program (Spain) under contract number RYC-2015-18820. We also warmly acknowledge the Laboratori Nazionali del Gran Sasso (LNGS) and the Dark Side collaboration for their help with TPB coating of various parts of the NEXT-White TPC. Finally, we are grateful to the Laboratorio Subterraneo de Canfranc for hosting and supporting the NEXT experiment.Fernandes, A.; Henriques, C.; Mano, R.; González-Díaz, D.; Azevedo, C.; Silva, P.; Gómez-Cadenas, J.... (2020). Low-diffusion Xe-He gas mixtures for rare-event detection: electroluminescence yield. Journal of High Energy Physics (Online). (4):1-18. https://doi.org/10.1007/JHEP04(2020)034S1184D.R. Nygren, Columnar recombination: a tool for nuclear recoil directional sensitivity in a xenon-based direct detection WIMP search, J. Phys. Conf. Ser.460 (2013) 012006 [INSPIRE].G. Mohlabeng et al., Dark matter directionality revisited with a high pressure xenon gas detector, JHEP07 (2015) 092 [arXiv:1503.03937] [INSPIRE].N.S. Phan, R.J. Lauer, E.R. Lee, D. Loomba, J.A.J. Matthews and E.H. Miller, GEM-based TPC with CCD Imaging for Directional Dark Matter Detection, Astropart. Phys.84 (2016) 82 [arXiv:1510.02170] [INSPIRE].J. Martin-Albo et al., Sensitivity of NEXT-100 to neutrinoless double beta decay, JHEP05 (2016) 159 [arXiv:1511.09246] [INSPIRE].K. Nakamura et al., AXEL — a high pressure xenon gas TPC for neutrinoless double beta decay search, Nucl. Instrum. Meth.A 845 (2017) 394 [INSPIRE].D. Yu. Akimov, A.A. Burenkov, V.F. Kuzichev, V.L. Morgunov and V.N. Solovev, Low background experiments with high pressure gas scintillation proportional detector, physics/9704021 [INSPIRE].Yu. M. Gavrilyuk et al., A technique for searching for the 2K capture in124Xe with a copper proportional counter, Phys. Atom. Nucl.78 (2015) 1563 [INSPIRE].Yu. M. Gavrilyuk et al., Results of In-Depth Analysis of Data Obtained in the Experimental Search for 2K (2ν)-Capture in78Kr, Phys. Part. Nucl.49 (2018) 540 [INSPIRE].C.A.N. Conde and A.J.P.L. Policarpo, A Gas Proportional Scintillation Counter, Nucl. Instrum. Meth.53 (1967) 7.A.J.P.L. Policarpo, M.A.F. Alves and C.A.N. Conde, The Argon-Nitrogen Proportional Scintillation Counter, Nucl. Instrum. Meth.55 (1967) 105.J.M.F. dos Santos et al., Development of portable gas proportional scintillation counters for x-ray spectrometry, X-Ray Spectrom.30 (2001) 373.NEXT collaboration, Accurate γ and MeV-electron track reconstruction with an ultra-low diffusion Xenon/TMA TPC at 10 atm, Nucl. Instrum. Meth.A 804 (2015) 8 [arXiv:1504.03678] [INSPIRE].NEXT collaboration, Characterisation of NEXT-DEMO using xenon KαX-rays, 2014 JINST9 P10007 [arXiv:1407.3966] [INSPIRE].NEXT collaboration, Energy calibration of the NEXT-White detector with 1% resolution near Qββof136Xe, JHEP10 (2019) 230 [arXiv:1905.13110] [INSPIRE].R. Lüscher et al., Search for beta beta decay in Xe-136: New results from the Gotthard experiment, Phys. Lett.B 434 (1998) 407 [INSPIRE].NEXT collaboration, First proof of topological signature in the high pressure xenon gas TPC with electroluminescence amplification for the NEXT experiment, JHEP01 (2016) 104 [arXiv:1507.05902] [INSPIRE].NEXT collaboration, Background rejection in NEXT using deep neural networks, 2017 JINST12 T01004 [arXiv:1609.06202] [INSPIRE].NEXT collaboration, The Next White (NEW) Detector, 2018 JINST13 P12010 [arXiv:1804.02409] [INSPIRE].H. Qiao et al., Signal-background discrimination with convolutional neural networks in the PandaX-III experiment using MC simulation, Sci. China Phys. Mech. Astron.61 (2018) 101007 [arXiv:1802.03489] [INSPIRE].NEXT collaboration, Secondary scintillation yield of xenon with sub-percent levels of CO2additive for rare-event detection, Phys. Lett.B 773 (2017) 663 [arXiv:1704.01623] [INSPIRE].C.M.B. Monteiro et al., Secondary Scintillation Yield in Pure Xenon, 2007 JINST2 P05001 [physics/0702142] [INSPIRE].C.M.B. Monteiro, J.A.M. Lopes, J.F. C.A. Veloso and J.M.F. dos Santos, Secondary scintillation yield in pure argon, Phys. Lett.B 668 (2008) 167 [INSPIRE].C.A.B. Oliveira et al., A simulation toolkit for electroluminescence assessment in rare event experiments, Phys. Lett.B 703 (2011) 217 [arXiv:1103.6237] [INSPIRE].E.D.C. Freitas et al., Secondary scintillation yield in high-pressure xenon gas for neutrinoless double beta decay (0νββ) search, Phys. Lett.B 684 (2010) 205 [INSPIRE].C.M.B. Monteiro et al., Secondary scintillation yield from gaseous micropattern electron multipliers in direct dark matter detection, Phys. Lett.B 677 (2009) 133 [INSPIRE].C.M.B. Monteiro, L.M.P. Fernandes, J.F. C.A. Veloso, C.A.B. Oliveira and J.M.F. dos Santos, Secondary scintillation yield from GEM and THGEM gaseous electron multipliers for direct dark matter search, Phys. Lett.B 714 (2012) 18 [INSPIRE].C. Balan et al., MicrOMEGAs operation in high pressure xenon: Charge and scintillation readout, 2011 JINST6 P02006 [arXiv:1009.2960] [INSPIRE].C.M.B. Monteiro, L.M.P. Fernandes, J.F. C.A. Veloso and J.M.F. dos Santos, Secondary scintillation readout from GEM and THGEM with a large area avalanche photodiode, 2012 JINST7 P06012 [INSPIRE].C.D.R. Azevedo et al., An homeopathic cure to pure Xenon large diffusion, 2016 JINST11 C02007 [arXiv:1511.07189] [INSPIRE].C.D.R. Azevedo et al., Microscopic simulation of xenon-based optical TPCs in the presence of molecular additives, Nucl. Intrum. Meth.A 877 (2018) 157 [arXiv:1705.09481] [INSPIRE].NEXT collaboration, Electroluminescence TPCs at the Thermal Diffusion Limit, JHEP01 (2019) 027 [arXiv:1806.05891] [INSPIRE].R.C. Lanza et al., Gas scintillators for imaging of low energy isotopes, IEEE Trans. Nucl. Sci.34 (1987) 406.R. Felkai et al., Helium-Xenon mixtures to improve the topological signature in high pressure gas xenon TPCs, Nucl. Intrum. Meth.A 905 (2018) 82 [arXiv:1710.05600] [INSPIRE].NEXT collaboration, Electron Drift and Longitudinal Diffusion in High Pressure Xenon-Helium Gas Mixtures, 2019 JINST14 P08009 [arXiv:1902.05544] [INSPIRE].J.A.M. Lopes et al., A xenon gas proportional scintillation counter with a UV-sensitive large-area avalanche photodiode, IEEE Trans. Nucl. Sci.48 (2001) 312.C.M.B. Monteiro et al., An argon gas proportional scintillation counter with UV avalanche photodiode scintillation readout, IEEE Trans. Nucl. Sci.48 (2001) 1081.Advanced Photonix, Inc., 1240 Avenida Acaso, Camarillo, CA 93012, U.S.A. .L.M.P. Fernandes et al., Characterization of large area avalanche photodiodes in X-ray and VUV-light detection, 2007 JINST2 P08005 [physics/0702130] [INSPIRE].L.M.P. Fernandes, E.D.C. Freitas, M. Ball, J.J. Gomez-Cadenas, C.M.B. Monteiro, N. Yahlali et al., Primary and secondary scintillation measurements in a xenon Gas Proportional Scintillation Counter, 2010 JINST5 P09006 [Erratum ibid.5 (2010) A12001] [arXiv:1009.2719] [INSPIRE].C.A.B. Oliveira, M. Sorel, J. Martin-Albo, J.J. Gomez-Cadenas, A.L. Ferreira and J.F. C.A. Veloso, Energy Resolution studies for NEXT, 2011 JINST6 P05007 [arXiv:1105.2954] [INSPIRE].D.F. Anderson et al., A large area, gas scintillation proportional counter, Nucl. Instrum. Meth.163 (1979) 125.T.Z. Kowalski et al., Fano factor implications from gas scintillation proportional counter measurements, Nucl. Instrum. Meth.A 279 (1989) 567.T. Doke, Basic properties of high pressure xenon gas as detector medium, in Proceedings of the XeSAT, Tokyo Japan (2005), pg. 92.S.J.C. do Carmo et al., Experimental Study of the ω-Values and Fano Factors of Gaseous Xenon and Ar-Xe Mixtures for X-Rays, IEEE Trans. Nucl. Sci.55 (2008) 2637.A. Buzulutskov, E. Shemyakina, A. Bondar, A. Dolgov, E. Frolov, V. Nosov et al., Revealing neutral bremsstrahlung in two-phase argon electroluminescence, Astropart. Phys.103 (2018) 29 [arXiv:1803.05329] [INSPIRE]

Monte Carlo characterization of PETALO, a full-body liquid xenon-based PET detector

[EN] New detector approaches in Positron Emission Tomography imaging will play an important role in reducing costs, lowering administered radiation doses, and improving overall performance. PETALO employs liquid xenon as the active scintillating medium and UV-sensitive silicon photomultipliers for scintillation readout. The scintillation time in liquid xenon is fast enough to register time-of-flight information for each detected coincidence, and sufficient scintillation is produced with low enough fluctuations to obtain good energy resolution. The present simulation study examines a full-body-sized PETALO detector and evaluates its potential performance in PET image reconstruction.This work was supported by the European Research Council under grant ID 757829 and by Ministerio de Economia y Competitividad for grant FPA2016-78595-C3-1-R.Renner, J.; Romo-Luque, C.; Aliaga, RJ.; Álvarez-Puerta, V.; Ballester Merelo, FJ.; Benlloch-Rodríguez, J.; Carrión, J.... (2022). Monte Carlo characterization of PETALO, a full-body liquid xenon-based PET detector. Journal of Instrumentation. 17(5):1-14. https://doi.org/10.1088/1748-0221/17/05/P0504411417

Radiogenic backgrounds in the NEXT double beta decay experiment

[EN] Natural radioactivity represents one of the main backgrounds in the search for neutrinoless double beta decay. Within the NEXT physics program, the radioactivity- induced backgrounds are measured with the NEXT-White detector. Data from 37.9 days of low-background operations at the Laboratorio Subterraneo de Canfranc with xenon depleted in Xe-136 are analyzed to derive a total background rate of (0.84 +/- 0.02) mHz above 1000 keV. The comparison of data samples with and without the use of the radon abatement system demonstrates that the contribution of airborne-Rn is negligible. A radiogenic background model is built upon the extensive radiopurity screening campaign conducted by the NEXT collaboration. A spectral fit to this model yields the specific contributions of Co-60, K-40, Bi-214 and Tl-208 to the total background rate, as well as their location in the detector volumes. The results are used to evaluate the impact of the radiogenic backgrounds in the double beta decay analyses, after the application of topological cuts that reduce the total rate to (0.25 +/- 0.01) mHz. Based on the best-fit background model, the NEXT-White median sensitivity to the two-neutrino double beta decay is found to be 3.5 sigma after 1 year of data taking. The background measurement in a Q(beta beta)+/- 100 keV energy window validates the best-fit background model also for the neutrinoless double beta decay search with NEXT-100. Only one event is found, while the model expectation is (0.75 +/- 0.12) events.The NEXT collaboration acknowledges support from the following agencies and institutions: the European Research Council (ERC) under the Advanced Grant 339787-NEXT; the European Union's Framework Programme for Research and Innovation Horizon 2020 (2014-2020) under the Marie Sklodowska-Curie Grant Agreements No. 674896, 690575 and 740055; the Ministerio de Economia y Competitividad and the Ministerio de Ciencia, Innovacion y Universidades of Spain under grants FIS2014-53371-C04, RTI2018-095979, the Severo Ochoa Program SEV-2014-0398 and the Maria de Maetzu Program MDM-2016-0692; the GVA of Spain under grants PROMETEO/2016/120 and SEJI/2017/011; the Portuguese FCT under project PTDC/FIS-NUC/2525/2014, under project UID/FIS/04559/2013 to fund the activities of LIBPhys, and under grants PD/BD/105921/2014, SFRH/BPD/109180/2015 and SFRH/BPD/76842/2011; the U.S. Department of Energy under contracts number DE-AC02-06CH11357 (Argonne National Laboratory), DE-AC02-07CH11359 (Fermi National Accelerator Laboratory), DE-FG02-13ER42020 (Texas A&M) and DE-SC0019223/DE-SC0019054 (University of Texas at Arlington); and the University of Texas at Arlington. DGD acknowledges Ramon y Cajal program (Spain) under contract number RYC-2015-18820. We also warmly acknowledge the Laboratori Nazionali del Gran Sasso (LNGS) and the Dark Side collaboration for their help with TPB coating of various parts of the NEXT-White TPC. Finally, we are grateful to the Laboratorio Subterraneo de Canfranc for hosting and supporting the NEXT experiment.Novella, P.; Palmeiro, B.; Sorel, M.; Usón, A.; Ferrario, P.; Gómez-Cadenas, JJ.; Adams, C.... (2019). Radiogenic backgrounds in the NEXT double beta decay experiment. Journal of High Energy Physics (Online). (10):1-26. https://doi.org/10.1007/JHEP10(2019)051S12610KamLAND-Zen collaboration, Search for Majorana Neutrinos near the Inverted Mass Hierarchy Region with KamLAND-Zen, Phys. Rev. Lett.117 (2016) 082503 [arXiv:1605.02889] [INSPIRE].GERDA collaboration, Improved Limit on Neutrinoless Double-β Decay of76Ge from GERDA Phase II, Phys. Rev. Lett.120 (2018) 132503 [arXiv:1803.11100] [INSPIRE].NEXT collaboration, NEXT-100 Technical Design Report (TDR): Executive Summary, 2012JINST7 T06001 [arXiv:1202.0721] [INSPIRE].M. Redshaw, E. Wingfield, J. McDaniel and E.G. Myers, Mass and double-beta-decay Q value of Xe-136, Phys. Rev. Lett.98 (2007) 053003 [INSPIRE].EXO-200 collaboration, Improved measurement of the 2νββ half-life of136Xe with the EXO-200 detector, Phys. Rev.C 89 (2014) 015502 [arXiv:1306.6106] [INSPIRE].KamLAND-Zen collaboration, Measurement of the double-β decay half-life of136Xe with the KamLAND-Zen experiment, Phys. Rev.C 85 (2012) 045504 [arXiv:1201.4664] [INSPIRE].NEXT collaboration, Initial results on energy resolution of the NEXT-White detector, 2018JINST13 P10020 [arXiv:1808.01804] [INSPIRE].NEXT collaboration, Energy Calibration of the NEXT-White Detector with 1% Resolution Near Qββof136Xe, arXiv:1905.13110 [INSPIRE].NEXT collaboration, Near-Intrinsic Energy Resolution for 30 to 662 keV Gamma Rays in a High Pressure Xenon Electroluminescent TPC, Nucl. Instrum. Meth.A 708 (2013) 101 [arXiv:1211.4474] [INSPIRE].NEXT collaboration, Characterisation of NEXT-DEMO using xenon KαX-rays, 2014JINST9 P10007 [arXiv:1407.3966] [INSPIRE].NEXT collaboration, First proof of topological signature in the high pressure xenon gas TPC with electroluminescence amplification for the NEXT experiment, JHEP01 (2016) 104 [arXiv:1507.05902] [INSPIRE].NEXT collaboration, Demonstration of the event identification capabilities of the NEXT-White detector, arXiv:1905.13141 [INSPIRE].A.D. 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NEXT-CRAB-0: a high pressure gaseous xenon time projection chamber with a direct VUV camera based readout

The NEXT collaboration: et al.The search for neutrinoless double beta decay (0νββ) remains one of the most compelling experimental avenues for the discovery in the neutrino sector. Electroluminescent gas-phase time projection chambers are well suited to 0νββ searches due to their intrinsically precise energy resolution and topological event identification capabilities. Scalability to ton- and multi-ton masses requires readout of large-area electroluminescent regions with fine spatial resolution, low radiogenic backgrounds, and a scalable data acquisition system. This paper presents a detector prototype that records event topology in an electroluminescent xenon gas TPC via VUV image-intensified cameras. This enables an extendable readout of large tracking planes with commercial devices that reside almost entirely outside of the active medium. Following further development in intermediate scale demonstrators, this technique may represent a novel and enlargeable method for topological event imaging in 0νββ.This work was supported by the US Department of Energy under awards DE-SC0019054 and DE-SC0019223, the US National Science Foundation under award number NSF CHE 2004111 and the Robert A Welch Foundation under award number Y-2031-20200401 (University of Texas Arlington). FJS was supported by the DOE Nuclear Physics Traineeship Program award DESC0022359. The NEXT Collaboration also acknowledges support from the following agencies and institutions: the European Research Council (ERC) under Grant Agreement No. 951281-BOLD; the European Union’s Framework Programme for Research and Innovation Horizon 2020 (2014–2020) under Grant Agreement No. 957202-HIDDEN; the MCIN/AEI of Spain and ERDF A way of making Europe under grants RTI2018-095979 and PID2021-125475NB, the Severo Ochoa Program grant CEX2018-000867-S and the Ramón y Cajal program grant RYC-2015-18820; the Generalitat Valenciana of Spain under grants PROMETEO/2021/087 and CIDEGENT/2019/049; the Department of Education of the Basque Government of Spain under the predoctoral training program non-doctoral research personnel; the Portuguese FCT under project UID/FIS/04559/2020 to fund the activities of LIBPhys-UC; the Israel Science Foundation (ISF) under grant 1223/21; the Pazy Foundation (Israel) under grants 310/22, 315/19 and 465; the US Department of Energy under contracts number DE-AC02-06CH11357 (Argonne National Laboratory), DE-AC02-07CH11359 (Fermi National Accelerator Laboratory), DE-FG02-13ER42020 (Texas A&M). Finally, we are grateful to the Laboratorio Subterraneo de Canfranc for hosting and supporting the NEXT experiment.With funding from the Spanish government through the "Severo Ochoa Centre of Excellence" accreditation (CEX2018-000867-S).Peer reviewe