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Author NEXT Collaboration (Jones, B.J.P. et al); Carcel, S.; Carrion, J.V.; Diaz, J.; Martin-Albo, J.; Martinez, A.; Martinez-Vara, M.; Muñoz Vidal, J.; Novella, P.; Palmeiro, B.; Querol, M.; Romo-Luque, C.; Sorel, M.; Uson, A.; Yahlali, N. url  doi
openurl 
  Title The dynamics of ions on phased radio-frequency carpets in high pressure gases and application for barium tagging in xenon gas time projection chambers Type Journal Article
  Year 2022 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A  
  Volume (down) 1039 Issue Pages 167000 - 19pp  
  Keywords RF carpets; Ion transport; Neutrinoless double beta decay; Barium tagging  
  Abstract Radio-frequency (RF) carpets with ultra-fine pitches are examined for ion transport in gases at atmospheric pressures and above. We develop new analytic and computational methods for modeling RF ion transport at densities where dynamics are strongly influenced by buffer gas collisions. An analytic description of levitating and sweeping forces from phased arrays is obtained, then thermodynamic and kinetic principles are used to calculate ion loss rates in the presence of collisions. This methodology is validated against detailed microscopic SIMION simulations. We then explore a parameter space of special interest for neutrinoless double beta decay experiments: transport of barium ions in xenon at pressures from 1 to 10 bar. Our computations account for molecular ion formation and pressure dependent mobility as well as finite temperature effects. We discuss the challenges associated with achieving suitable operating conditions, which lie beyond the capabilities of existing devices, using presently available or near-future manufacturing techniques.  
  Address [Hauptman, J.] Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA, Email: ben.jones@uta.edu  
  Corporate Author Thesis  
  Publisher Elsevier Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0168-9002 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000861747900008 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5372  
Permanent link to this record
 

 
Author Alvarez, V.; Herrero-Bosch, V.; Esteve, R.; Laing, A.; Rodriguez, J.; Querol, M.; Monrabal, F.; Toledo, J.F.; Gomez-Cadenas, J.J. url  doi
openurl 
  Title The electronics of the energy plane of the NEXT-White detector Type Journal Article
  Year 2019 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A  
  Volume (down) 917 Issue Pages 68-76  
  Keywords Calorimetry; Front-end electronics; Digital baseline restoration  
  Abstract 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 0.4 mV.  
  Address [Alvarez, V; Laing, A.; Rodriguez, J.; Querol, M.; Gomez-Cadenas, J. J.] CSIC, IFIC, Inst Fis Corpuscular, Calle Catedrat Jose Beltran 2, Valencia 46980, Spain, Email: vicente.alvarez@ific.uv.es  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0168-9002 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000455016500010 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 3868  
Permanent link to this record
 

 
Author NEXT Collaboration (Trindade, A.M.F. et al); Alvarez, V.; Benlloch-Rodriguez, J.M.; Botas, A.; Carcel, S.; Carrion, J.V.; Diaz, J.; Felkai, R.; Ferrario, P.; Gomez-Cadenas, J.J.; Laing, A.; Liubarsky, I; Lopez-March, N.; Martinez, A.; Muñoz Vidal, J.; Musti, M.; Nebot-Guinot, M.; Novella, P.; Palmeiro, B.; Perez, J.; Querol, M.; Renner, J.; Rodriguez, J.; Simon, A.; Sorel, M.; Torrent, J.; Yahlali, N. doi  openurl
  Title Study of the loss of xenon scintillation in xenon-trimethylamine mixtures Type Journal Article
  Year 2018 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A  
  Volume (down) 905 Issue Pages 22-28  
  Keywords Gaseous radiation detectors; Noble gas mixtures; Molecular additives; VUV absorption  
  Abstract This work investigates the capability of TMA ((CH3)(3)N) molecules to shift the wavelength of Xe VUV emission (160-188 nm) to a longer, more manageable, wavelength (260-350 nm). Light emitted from a Xe lamp was passed through a gas chamber filled with Xe-TMA mixtures at 800 Torr and detected with a photomultiplier tube. Using bandpass filters in the proper transmission ranges, no reemitted light was observed experimentally. Considering the detection limit of the experimental system, if reemission by TMA molecules occurs, it is below 0.3% of the scintillation absorbed in the 160-188 nm range. An absorption coefficient value for xenon VUV light by TMA of 0.43 +/- 0.03 cm(-1) Torr(-1) was also obtained. These results can be especially important for experiments considering TMA as a molecular additive to Xe in large volume optical time projection chambers.  
  Address [Trindade, A. M. F.; Escada, J.; Cortez, A. F., V; Borges, F. I. G. M.; Santos, F. P.; Conde, C. A. N.] LIP Lab Instrumentacao & Fis Expt Particulas, Coimbra, Portugal, Email: Kalexandre.trindade@coimbra.lip.pt  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0168-9002 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000444425700003 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 3730  
Permanent link to this record
 

 
Author NEXT Collaboration (Felkai, R. et al); Sorel, M.; Lopez-March, N.; Gomez-Cadenas, J.J.; Alvarez, V.; Benlloch-Rodriguez, J.M.; Botas, A.; Carcel, S.; Carrion, J.V.; Diaz, J.; Ferrario, P.; Laing, A.; Martinez, A.; Muñoz Vidal, J.; Musti, M.; Nebot-Guinot, M.; Novella, P.; Palmeiro, B.; Perez, J.; Querol, M.; Renner, J.; Romo-Luque, C.; Rodriguez, J.; Simon, A.; Torrent, J.; Yahlali, N. url  doi
openurl 
  Title Helium-Xenon mixtures to improve the topological signature in high pressure gas xenon TPCs Type Journal Article
  Year 2018 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A  
  Volume (down) 905 Issue Pages 82-90  
  Keywords Helium; Xenon; Double-beta decay; TPC; Low diffusion; Electroluminescence  
  Abstract Within the framework of xenon-based double beta decay experiments, we propose the possibility to improve the background rejection of an electroluminescent Time Projection Chamber (EL TPC) by reducing the diffusion of the drifting electrons while keeping nearly intact the energy resolution of a pure xenon EL TPC. Based on state-of-the-art microscopic simulations, a substantial addition of helium, around 10 or 15 %, may reduce drastically the transverse diffusion down to 2.5 mm/root m from the 10.5 mm/root m of pure xenon. The longitudinal diffusion remains around 4 mm/root m. Light production studies have been performed as well. They show that the relative variation in energy resolution introduced by such a change does not exceed a few percent, which leaves the energy resolution practically unchanged. The technical caveats of using photomultipliers close to an helium atmosphere are also discussed in detail.  
  Address [Adams, C.; Guenette, R.; Martin-Albo, J.] Harvard Univ, Dept Phys, Cambridge, MA 02138 USA, Email: francesc.monrabalcapilla@uta.edu  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0168-9002 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000444425700010 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 3731  
Permanent link to this record
 

 
Author NEXT Collaboration (Azevedo, C.D.R. et al); Gomez-Cadenas, J.J.; Alvarez, V.; Benlloch-Rodriguez, J.M.; Botas, A.; Carcel, S.; Carrion, J.V.; Diaz, J.; Felkai, R.; Ferrario, P.; Laing, A.; Liubarsky, I.; Lopez-March, N.; Martin-Albo, J.; Martinez, A.; Muñoz Vidal, J.; Musti, M.; Nebot-Guinot, M.; Novella, P.; Palmeiro, B.; Querol, M.; Renner, J.; Rodriguez, J.; Serra, L.; Simon, A.; Sorel, M.; Yahlali, N. url  doi
openurl 
  Title Microscopic simulation of xenon-based optical TPCs in the presence of molecular additives Type Journal Article
  Year 2018 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A  
  Volume (down) 877 Issue Pages 157-172  
  Keywords Optical TPCs; Microscopic simulation; Xenon scintillation  
  Abstract We introduce a simulation framework for the transport of high and low energy electrons in xenon-based optical time projection chambers (OTPCs). The simulation relies on elementary cross sections (electron-atom and electron-molecule) and incorporates, in order to compute the gas scintillation, the reaction/quenching rates (atom-atom and atom-molecule) of the first 41 excited states of xenon and the relevant associated excimers, together with their radiative cascade. The results compare positively with observations made in pure xenon and its mixtures with CO2 and CF4 in a range of pressures from 0.1 to 10 bar. This work sheds some light on the elementary processes responsible for the primary and secondary xenon-scintillation mechanisms in the presence of additives, that are of interest to the OTPC technology.  
  Address [Azevedo, C. D. R.] Univ Aveiro, I3N, Phys Dept, Aveiro, Portugal, Email: Diego.Gonzalez.Diaz@usc.es  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0168-9002 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000415128000022 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 3371  
Permanent link to this record
 

 
Author NEXT Collaboration (Henriques, C.A.O. et al); Gomez-Cadenas, J.J.; Alvarez, V.; Benlloch-Rodriguez, J.; Botas, A.; Carcel, S.; Carrion, J.V.; Diaz, J.; Felkai, R.; Ferrario, P.; Laing, A.; Liubarsky, I.; Lopez-March, N.; Martin-Albo, J.; Martinez, A.; Muñoz Vidal, J.; Musti, M.; Nebot-Guinot, M.; Novella, P.; Palmeiro, B.; Perez, J.; Querol, M.; Renner, J.; Rodriguez, J.; Serra, L.; Simon, A.; Sorel, M.; Torrent, J.; Yahlali, N. url  doi
openurl 
  Title Secondary scintillation yield of xenon with sub-percent levels of CO2 additive for rare-event detection Type Journal Article
  Year 2017 Publication Physics Letters B Abbreviated Journal Phys. Lett. B  
  Volume (down) 773 Issue Pages 663-671  
  Keywords Double beta decay; Neutrino; Rare event detection; Electroluminescence; Secondary scintillation; Xenon  
  Abstract Xe-CO2 mixtures are important alternatives to pure xenon in Time Projection Chambers (TPC) based on secondary scintillation (electroluminescence) signal amplification with applications in the important field of rare event detection such as directional dark matter, double electron capture and double beta decay detection. The addition of CO2 to pure xenon at the level of 0.05-0.1% can reduce significantly the scale of electron diffusion from 10 mm/root m to 2.5 mm/root m, with high impact on the discrimination of the events through pattern recognition of the topology of primary ionization trails. We have measured the electroluminescence (EL) yield of Xe-CO2 mixtures, with sub-percent CO2 concentrations. We demonstrate that the EL production is still high in these mixtures, 70% and 35% relative to that produced in pure xenon, for CO2 concentrations around 0.05% and 0.1%, respectively. The contribution of the statistical fluctuations in EL production to the energy resolution increases with increasing CO2 concentration, being smaller than the contribution of the Fano factor for concentrations below 0.1% CO2.  
  Address [Henriques, C. A. O.; Freitas, E. D. C.; Mano, R. D. P.; Jorge, M. R.; Fernandes, L. M. P.; Monteiro, C. M. B.; dos Santos, J. M. F.] Univ Coimbra, Phys Dept, LIBPhys, Rua Larga, P-3004516 Coimbra, Portugal, Email: cristina@gian.fis.uc.pt  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0370-2693 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000413294200099 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 3342  
Permanent link to this record
 

 
Author NEXT Collaboration (Novella, P. et al); Carcel, S.; Carrion, J.V.; Diaz, J.; Martin-Albo, J.; Martinez, A.; Martinez-Vara, M.; Muñoz Vidal, J.; Palmeiro, B.; Querol, M.; Romo-Luque, C.; Sorel, M.; Uson, A.; Yahlali, N. url  doi
openurl 
  Title Measurement of the Xe-136 two-neutrino double-beta-decay half-life via direct background subtraction in NEXT Type Journal Article
  Year 2022 Publication Physical Review C Abbreviated Journal Phys. Rev. C  
  Volume (down) 105 Issue 5 Pages 055501 - 8pp  
  Keywords  
  Abstract We report a measurement of the half-life of the Xe-136 two-neutrino double-beta decay performed with a novel direct-background-subtraction technique. The analysis relies on the data collected with the NEXT-White detector operated with Xe-136-enriched and Xe-136-depleted xenon, as well as on the topology of double-electron tracks. With a fiducial mass of only 3.5 kg of Xe, a half-life of 2.34(-0.46)(+0.80) (stat)(-0.17)(+0.30) (sys) x 10(21) yr is derived from the background-subtracted energy spectrum. The presented technique demonstrates the feasibility of unique background-model-independent neutrinoless double-beta-decay searches.  
  Address [Novella, P.; Sorel, M.; Uson, A.; Carcel, S.; Carrion, J., V; Diaz, J.; Martin-Albo, J.; Martinez, A.; Martinez-Vara, M.; Vidal, J. Munoz; Palmeiro, B.; Querol, M.; Romo-Luque, C.; Yahlali, N.] CSIC, Inst Fis Corpuscular IFIC, Calle Catedrat Jose Beltran 2, E-46980 Paterna, Spain, Email: auson@ific.uv.es  
  Corporate Author Thesis  
  Publisher Amer Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2469-9985 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000810927800003 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5263  
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. url  doi
openurl 
  Title 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 (down) 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; Carcel, S.; Carrion, J.V.; Felkai, R.; Kekic, M.; Lopez-March, N.; Martin-Albo, J.; Martinez, A.; Martinez-Lema, G.; Muñoz Vidal, J.; Novella, P.; Palmeiro, B.; Querol, M.; Romo-Luque, C.; Sorel, M.; Uson, A.; Yahlali, N. url  doi
openurl 
  Title Mitigation of backgrounds from cosmogenic Xe-137 in xenon gas experiments using He-3 neutron capture Type Journal Article
  Year 2020 Publication Journal of Physics G Abbreviated Journal J. Phys. G  
  Volume (down) 47 Issue 7 Pages 075001 - 17pp  
  Keywords gaseous detectors; scintillators; scintillation and light emission processes; solid; gas and liquid scintillators  
  Abstract Xe-136 is used as the target medium for many experiments searching for 0 nu beta beta. Despite underground operation, cosmic muons that reach the laboratory can produce spallation neutrons causing activation of detector materials. A potential background that is difficult to veto using muon tagging comes in the form of Xe-137 created by the capture of neutrons on Xe-136. This isotope decays via beta decay with a half-life of 3.8 min and a Q(beta) of similar to 4.16 MeV. This work proposes and explores the concept of adding a small percentage of He-3 to xenon as a means to capture thermal neutrons and reduce the number of activations in the detector volume. When using this technique we find the contamination from Xe-137 activation can be reduced to negligible levels in tonne and multi-tonne scale high pressure gas xenon neutrinoless double beta decay experiments running at any depth in an underground laboratory.  
  Address [Rogers, L.; Jones, B. J. P.; Laing, A.; Pingulkar, S.; Smithers, B.; Woodruff, K.; Byrnes, N.; Dingler, R.; McDonald, A. D.; Nygren, D. R.] Univ Texas Arlington, Dept Phys, POB 19059, Arlington, TX 76019 USA, Email: leslie.rogers@mavs.uta.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 0954-3899 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000537753800001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 4423  
Permanent link to this record
 

 
Author Esteve, R.; Toledo, J.F.; Herrero, V.; Simon, A.; Monrabal, F.; Alvarez, V.; Rodriguez, J.; Querol, M.; Ballester, F. doi  openurl
  Title The Event Detection System in the NEXT-White Detector Type Journal Article
  Year 2021 Publication Sensors Abbreviated Journal Sensors  
  Volume (down) 21 Issue 2 Pages 673 - 18pp  
  Keywords xenon TPC; trigger concepts; data acquisition circuits; FPGA  
  Abstract This article describes the event detection system of the NEXT-White detector, a 5 kg high pressure xenon TPC with electroluminescent amplification, located in the Laboratorio Subterraneo de Canfranc (LSC), Spain. The detector is based on a plane of photomultipliers (PMTs) for energy measurements and a silicon photomultiplier (SiPM) tracking plane for offline topological event filtering. The event detection system, based on the SRS-ATCA data acquisition system developed in the framework of the CERN RD51 collaboration, has been designed to detect multiple events based on online PMT signal energy measurements and a coincidence-detection algorithm. Implemented on FPGA, the system has been successfully running and evolving during NEXT-White operation. The event detection system brings some relevant and new functionalities in the field. A distributed double event processor has been implemented to detect simultaneously two different types of events thus allowing simultaneous calibration and physics runs. This special feature provides constant monitoring of the detector conditions, being especially relevant to the lifetime and geometrical map computations which are needed to correct high-energy physics events. Other features, like primary scintillation event rejection, or a double buffer associated with the type of event being searched, help reduce the unnecessary data throughput thus minimizing dead time and improving trigger efficiency.  
  Address [Esteve Bosch, Raul; Toledo Alarcon, Jose F.; Herrero Bosch, Vicente; Alvarez Puerta, Vicente; Rodriguez Samaniego, Javier; Ballester Merelo, Francisco] Univ Politecn Valencia, CSIC, Inst Instrumentac Imagen Mol I3M, Ctr Mixto, Camino Vera S-N, Valencia 46022, Spain, Email: rauesbos@eln.upv.es;  
  Corporate Author Thesis  
  Publisher Mdpi Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000611719600001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 4693  
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