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358 results on '"Shuman, D."'

1. Microscopic simulation of xenon-based optical TPCs in the presence of molecular additives

Author: Azevedo, C. D. R., Gonzalez-Diaz, D., Biagi, S. F., Oliveira, C. A. B., Henriques, C. A. O., Escada, J., Monrabal, F., Gómez-Cadenas, J. J., Álvarez, V., Borges, J. M. Benlloch-Rodríguez F. I. G. M., Botas, A., Cárcel, S., Carrión, J. V., Cebrián, S., Conde, C. A. N., Díaz, J., Diesburg, M., Esteve, R., Felkai, R., Fernandes, L. M. P., Ferrario, P., Ferreira, A. L., Freitas, E. D. C., Goldschmidt, A., Gutiérrez, R. M., Hauptman, J., Hernandez, A. I., Morata, J. A. Hernando, Herrero, V., Jones, B. J. P., Labarga, L., Laing, A., Lebrun, P., Liubarsky, I., Lopez-March, N., Losada, M., Martín-Albo, J., Martínez, A., McDonald, A. D., Monteiro, C. M. B., Mora, F. J., Moutinho, L. M., Vidal, J. Muñoz, Musti, M., Nebot-Guinot, M., Novella, P., Nygren, D., Palmeiro, B., Para, A., Pérez, J., Querol, M., Renner, J., Ripoll, L., Rodríguez, J., Rogers, L., Santos, F. P., Santos, J. M. F. dos, Serra, L., Shuman, D., Simón, A., Sofka, C., Sorel, M., Stiegler, T., Toledo, J. F., Torrent, J., Tsamalaidze, Z., Veloso, J. F. C. A., Webb, R., White, J. T., and Yahlali, N.
Subjects: Physics - Instrumentation and Detectors
Abstract: We introduce a simulation framework for the transport of high and low energy electrons in xenon-based gaseous 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 CO$_2$ and CF$_4$ 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.
Published: 2017
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2. Background rejection in NEXT using deep neural networks

Author: NEXT Collaboration, Renner, J., Farbin, A., Vidal, J. Muñoz, Benlloch-Rodríguez, J. M., Botas, A., Ferrario, P., Gómez-Cadenas, J. J., Álvarez, V., Azevedo, C. D. R., Borges, F. I. G., Cárcel, S., Carrión, J. V., Cebrián, S., Cervera, A., Conde, C. A. N., Díaz, J., Diesburg, M., Esteve, R., Fernandes, L. M. P., Ferreira, A. L., Freitas, E. D. C., Goldschmidt, A., González-Díaz, D., Gutiérrez, R. M., Hauptman, J., Henriques, C. A. O., Morata, J. A. Hernando, Herrero, V., Jones, B., Labarga, L., Laing, A., Lebrun, P., Liubarsky, I., López-March, N., Lorca, D., Losada, M., Martín-Albo, J., Martínez-Lema, G., Martínez, A., Monrabal, F., Monteiro, C. M. B., Mora, F. J., Moutinho, L. M., Nebot-Guinot, M., Novella, P., Nygren, D., Para, A., Pérez, J., Querol, M., Ripoll, L., Rodríguez, J., Santos, F. P., Santos, J. M. F. dos, Serra, L., Shuman, D., Simón, A., Sofka, C., Sorel, M., Toledo, J. F., Torrent, J., Tsamalaidze, Z., Veloso, J. F. C. A., White, J., Webb, R., Yahlali, N., and Yepes-Ramírez, H.
Subjects: Physics - Instrumentation and Detectors, High Energy Physics - Experiment
Abstract: We investigate the potential of using deep learning techniques to reject background events in searches for neutrinoless double beta decay with high pressure xenon time projection chambers capable of detailed track reconstruction. The differences in the topological signatures of background and signal events can be learned by deep neural networks via training over many thousands of events. These networks can then be used to classify further events as signal or background, providing an additional background rejection factor at an acceptable loss of efficiency. The networks trained in this study performed better than previous methods developed based on the use of the same topological signatures by a factor of 1.2 to 1.6, and there is potential for further improvement., Comment: 21 pages, 9 figures; formatting changes
Published: 2016
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3. Sensitivity of NEXT-100 to neutrinoless double beta decay

Author: NEXT Collaboration, Martín-Albo, J., Vidal, J. Muñoz, Ferrario, P., Nebot-Guinot, M., Gómez-Cadenas, J. J., Álvarez, V., Azevedo, C. D. R., Borges, F. I. G., Cárcel, S., Cebrián, S., Cervera, A., Conde, C. A. N., Díaz, J., Diesburg, M., Esteve, R., Fernandes, L. M. P., Ferreira, A. L., Freitas, E. D. C., Goldschmidt, A., González-Díaz, D., Gutiérrez, R. M., Hauptman, J., Henriques, C. A. O., Morata, J. A. Hernando, Labarga, L., Laing, A., Lebrun, P., Liubarsky, I., López-March, N., Lorca, D., Losada, M., Martínez-Lema, G., Martínez, A., Monrabal, F., Monteiro, C. M. B., Mora, F. J., Moutinho, L. M., Novella, P., Nygren, D., Palmeiro, B., Para, A., Pérez, J., Querol, M., Renner, J., Ripoll, L., Rodríguez, J., Santos, F. P., Santos, J. M. F. dos, Serra, L., Shuman, D., Simón, A., Sofka, C., Sorel, M., Stiegler, T., Toledo, J. F., Torrent, J., Tsamalaidze, Z., Veloso, J. F. C. A., Webb, R., White, J. T., Yahlali, N., and Yepes-Ramírez, H.
Subjects: Physics - Instrumentation and Detectors, High Energy Physics - Experiment, Nuclear Experiment
Abstract: NEXT-100 is an electroluminescent high-pressure xenon gas time projection chamber that will search for the neutrinoless double beta ($\beta \beta 0 \nu$) decay of Xe-136. The detector possesses two features of great value for $\beta \beta 0 \nu$ searches: energy resolution better than 1\% FWHM at the $Q$ value of Xe-136 and track reconstruction for the discrimination of signal and background events. This combination results in excellent sensitivity, as discussed in this paper. Material-screening measurements and a detailed Monte Carlo detector simulation predict a background rate for NEXT-100 of at most $4\times10^{-4}$ counts keV$^{-1}$ kg$^{-1}$ yr$^{-1}$. Accordingly, the detector will reach a sensitivity to the \bbonu-decay half-life of $2.8\times10^{25}$ years (90\% CL) for an exposure of 100 $\mathrm{kg}\cdot\mathrm{year}$, or $6.0\times10^{25}$ years after a run of 3 effective years., Comment: Accepted for publication in the Journal of High Energy Physics (JHEP)
Published: 2015
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4. First proof of topological signature in the high pressure xenon gas TPC with electroluminescence amplification for the NEXT experiment

Author: NEXT Collaboration, Ferrario, P., Laing, A., López-March, N., Gómez-Cadenas, J. J., Álvarez, V., Azevedo, C. D. R., Borges, F. I. G., Cárcel, S., Cebrián, S., Cervera, A., Conde, C. A. N., Dafni, T., Díaz, J., Diesburg, M., Esteve, R., Fernandes, L. M. P., Ferreira, A. L., Freitas, E. D. C., Gehman, V. M., Goldschmidt, A., González-Díaz, D., Gutiérrez, R. M., Hauptman, J., Henriques, C. A. O., Morata, J. A. Hernando, Irastorza, I. G., Labarga, L., Lebrun, P., Liubarsky, I., Lorca, D., Losada, M., Luzón, G., Marí, A., Martín-Albo, J., Martínez-Lema, G., Martínez, A., Miller, T., Monrabal, F., Monserrate, M., Monteiro, C. M. B., Mora, F. J., Moutinho, L. M., Vidal, J. Muñoz, Nebot-Guinot, M., Novella, P., Nygren, D., Para, A., Pérez, J., Aparicio, J. L. Pérez, Querol, M., Renner, J., Ripoll, L., Rodríguez, J., Santos, F. P., Santos, J. M. F. dos, Serra, L., Shuman, D., Simón, A., Sofka, C., Sorel, M., Toledo, J. F., Torrent, J., Tsamalaidze, Z., Veloso, J. F. C. A., Villar, J. A., Webb, R., White, J. T., Yahlali, N., and Yepes-Ramírez, H.
Subjects: Physics - Instrumentation and Detectors, High Energy Physics - Experiment
Abstract: The NEXT experiment aims to observe the neutrinoless double beta decay of xenon in a high-pressure Xe136 gas TPC using electroluminescence (EL) to amplify the signal from ionization. One of the main advantages of this technology is the possibility to reconstruct the topology of events with energies close to Qbb. This paper presents the first demonstration that the topology provides extra handles to reject background events using data obtained with the NEXT-DEMO prototype. Single electrons resulting from the interactions of Na22 1275 keV gammas and electron-positron pairs produced by conversions of gammas from the Th228 decay chain were used to represent the background and the signal in a double beta decay. These data were used to develop algorithms for the reconstruction of tracks and the identification of the energy deposited at the end-points, providing an extra background rejection factor of 24.3 +- 1.4 (stat.)%, while maintaining an efficiency of 66.7 +- 1% for signal events.
Published: 2015

5. Radon and material radiopurity assessment for the NEXT double beta decay experiment

Author: Cebrián, S., Pérez, J., Bandac, I., Labarga, L., Álvarez, V., Barrado, A. I., Bettini, A., Borges, F. I. G. M., Camargo, M., Cárcel, S., Cervera, A., Conde, C. A. N., Conde, E., Dafni, T., Díaz, J., Esteve, R., Fernandes, L. M. P., Fernández, M., Ferrario, P., Freitas, E. D. C., Gehman, V. M., Goldschmidt, A., Gómez-Cadenas, J. J., González-Díaz, D., Gutiérrez, R. M., Hauptman, J., Morata, J. A. Hernando, Herrera, D. C., Irastorza, I. G., Laing, A., Liubarsky, I., López-March, N., Lorca, D., Losada, M., Luzón, G., Marí, A., Martín-Albo, J., Martínez, A., Martínez-Lema, G., Miller, T., Monrabal, F., Monserrate, M., Monteiro, C. M. B., Mora, F. J., Moutinho, L. M., Vidal, J. Muñoz, Nebot-Guinot, M., Nygren, D., Oliveira, C. A. B., de Solórzano, A. Ortiz, Aparicio, J. L. Pérez, Querol, M., Renner, J., Ripoll, L., Rodríguez, J., Santos, F. P., Santos, J. M. F. dos, Serra, L., Shuman, D., Simón, A., Sofka, C., Sorel, M., Toledo, J. F., Torrent, J., Tsamalaidze, Z., Veloso, J. F. C. A., Villar, J. A., Webb, R. C., White, J. T., and Yahlali, N.
Subjects: Physics - Instrumentation and Detectors, High Energy Physics - Experiment, Nuclear Experiment
Abstract: The Neutrino Experiment with a Xenon TPC (NEXT), intended to investigate the neutrinoless double beta decay using a high-pressure xenon gas TPC filled with Xe enriched in 136Xe at the Canfranc Underground Laboratory in Spain, requires ultra-low background conditions demanding an exhaustive control of material radiopurity and environmental radon levels. An extensive material screening process is underway for several years based mainly on gamma-ray spectroscopy using ultra-low background germanium detectors in Canfranc but also on mass spectrometry techniques like GDMS and ICPMS. Components from shielding, pressure vessel, electroluminescence and high voltage elements and energy and tracking readout planes have been analyzed, helping in the final design of the experiment and in the construction of the background model. The latest measurements carried out will be presented and the implication on NEXT of their results will be discussed. The commissioning of the NEW detector, as a first step towards NEXT, has started in Canfranc; in-situ measurements of airborne radon levels were taken there to optimize the system for radon mitigation and will be shown too., Comment: Proceedings of the Low Radioactivity Techniques 2015 workshop (LRT2015), Seattle, March 2015
Published: 2015
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6. Accurate gamma and MeV-electron track reconstruction with an ultra-low diffusion Xenon/TMA TPC at 10 atmospheres

Author: Gonzalez-Diaz, Diego, Alvarez, V., Borges, F. I. G., Camargo, M., Carcel, S., Cebrian, S., Cervera, A., Conde, C. A. N., Dafni, T., Diaz, J., Esteve, R., Fernandes, L. M. P., Ferrario, P., Ferreira, A. L., Freitas, E. D. C., Gehman, V. M., Goldschmidt, A., Gomez-Cadenas, J. J., Gutierrez, R. M., Hauptman, J., Morata, J. A. Hernando, Herrera, D. C., Irastorza, I. G., Labarga, L., Laing, A., Liubarsky, I., Lopez-March, N., Lorca, D., Losada, M., Luzon, G., Mari, A., Martin-Albo, J., Martinez-Lema, G., Martinez, A., Miller, T., Monrabal, F., Monserrate, M., Monteiro, C. M. B., Mora, F. J., Moutinho, L. M., Vidal, J. Munoz, Nebot-Guinot, M., Nygren, D., Oliveira, C. A. B., Perez, J., Aparicio, J. L. Perez, Querol, M., Renner, J., Ripoll, L., Rodriguez, J., Santos, F. P., Santos, J. M. F. dos, Serra, L., Shuman, D., Simon, A., Sofka, C., Sorel, M., Toledo, J. F., Torrent, J., Tsamalaidze, Z., Veloso, J. F. C. A., Villar, J. A., Webb, R., White, J. T., Yahlali, N., Azevedo, C., Aznar, F., Calvet, D., Castel, J., Ferrer-Ribas, E., Garcia, J. A., Giomataris, I., Gomez, H., Iguaz, F. J., Lagraba, A., Coguie, A. Le, Mols, J. P., Sahin, O., Rodriguez, A., Ruiz-Choliz, E., Segui, L., Tomas, A., and Veenhof, R.
Subjects: Physics - Instrumentation and Detectors
Abstract: We report the performance of a 10 atm Xenon/trimethylamine time projection chamber (TPC) for the detection of X-rays (30 keV) and gamma-rays (0.511-1.275 MeV) in conjunction with the accurate tracking of the associated electrons. When operated at such a high pressure and in 1%-admixtures, trimethylamine (TMA) endows Xenon with an extremely low electron diffusion (1.3 +-0.13 mm-sigma (longitudinal), 0.8 +-0.15 mm-sigma (transverse) along 1 m drift) besides forming a convenient Penning-Fluorescent mixture. The TPC, that houses 1.1 kg of gas in its active volume, operated continuously for 100 live-days in charge amplification mode. The readout was performed through the recently introduced microbulk Micromegas technology and the AFTER chip, providing a 3D voxelization of 8mm x 8mm x 1.2mm for approximately 10 cm/MeV-long electron tracks. This work was developed as part of the R&D program of the NEXT collaboration for future detector upgrades in the search of the 0bbnu decay in 136Xe, specifically those based on novel gas mixtures. Therefore we ultimately focus on the calorimetric and topological properties of the reconstructed MeV-electron tracks.
Published: 2015
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7. Background rejection in NEXT using deep neural networks

Author: Renner, J, Farbin, A, Vidal, JM, Benlloch-Rodríguez, JM, Botas, A, Ferrario, P, Gómez-Cadenas, JJ, Álvarez, V, Azevedo, CDR, Borges, FIG, Cárcel, S, Carrión, JV, Cebrián, S, Cervera, A, Conde, CAN, Díaz, J, Diesburg, M, Esteve, R, Fernandes, LMP, Ferreira, AL, Freitas, EDC, Goldschmidt, A, González-Díaz, D, Gutiérrez, RM, Hauptman, J, Henriques, CAO, Morata, JAH, Herrero, V, Jones, B, Labarga, L, Laing, A, Lebrun, P, Liubarsky, I, López-March, N, Lorca, D, Losada, M, Martín-Albo, J, Martínez-Lema, G, Martínez, A, Monrabal, F, Monteiro, CMB, Mora, FJ, Moutinho, LM, Nebot-Guinot, M, Novella, P, Nygren, D, Palmeiro, B, Para, A, Pérez, J, Querol, M, Ripoll, L, Rodríguez, J, Santos, FP, Dos Santos, JMF, Serra, L, Shuman, D, Simón, A, Sofka, C, Sorel, M, Toledo, JF, Torrent, J, Tsamalaidze, Z, Veloso, JFCA, White, J, Webb, R, Yahlali, N, and Yepes-Ramírez, H
Subjects: Nuclear & Particles Physics, Other Physical Sciences, Physical Sciences, Engineering
Abstract: We investigate the potential of using deep learning techniques to reject background events in searches for neutrinoless double beta decay with high pressure xenon time projection chambers capable of detailed track reconstruction. The differences in the topological signatures of background and signal events can be learned by deep neural networks via training over many thousands of events. These networks can then be used to classify further events as signal or background, providing an additional background rejection factor at an acceptable loss of efficiency. The networks trained in this study performed better than previous methods developed based on the use of the same topological signatures by a factor of 1.2 to 1.6, and there is potential for further improvement.
Published: 2017

8. Sensitivity of NEXT-100 to neutrinoless double beta decay

Author: The NEXT collaboration, Martín-Albo, J, Muñoz Vidal, J, Ferrario, P, Nebot-Guinot, M, Gómez-Cadenas, JJ, Álvarez, V, Azevedo, CDR, Borges, FIG, Cárcel, S, Carrión, JV, Cebrián, S, Cervera, A, Conde, CAN, Díaz, J, Diesburg, M, Esteve, R, Fernandes, LMP, Ferreira, AL, Freitas, EDC, Goldschmidt, A, González-Díaz, D, Gutiérrez, RM, Hauptman, J, Henriques, CAO, Hernando Morata, JA, Herrero, V, Labarga, L, Laing, A, Lebrun, P, Liubarsky, I, López-March, N, Lorca, D, Losada, M, Martínez-Lema, G, Martínez, A, Monrabal, F, Monteiro, CMB, Mora, FJ, Moutinho, LM, Novella, P, Nygren, D, Palmeiro, B, Para, A, Querol, M, Renner, J, Ripoll, L, Rodríguez, J, Santos, FP, dos Santos, JMF, Serra, L, Shuman, D, Simón, A, Sofka, C, Sorel, M, Stiegler, T, Toledo, JF, Torrent, J, Tsamalaidze, Z, Veloso, JFCA, Webb, R, White, JT, Yahlali, N, and Yepes-Ramírez, H
Subjects: Nuclear and Plasma Physics, Particle and High Energy Physics, Synchrotrons and Accelerators, Physical Sciences, Mathematical Physics, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Quantum Physics, Nuclear & Particles Physics, Mathematical physics, Nuclear and plasma physics, Particle and high energy physics
Abstract: Abstract: NEXT-100 is an electroluminescent high-pressure xenon gas time projection chamber that will search for the neutrinoless double beta (0νββ) decay of 136Xe. The detector possesses two features of great value for 0νββ searches: energy resolution better than 1% FWHM at the Q value of 136Xe and track reconstruction for the discrimination of signal and background events. This combination results in excellent sensitivity, as discussed in this paper. Material-screening measurements and a detailed Monte Carlo detector simulation predict a background rate for NEXT-100 of at most 4 × 10−4 counts keV−1 kg−1 yr−1. Accordingly, the detector will reach a sensitivity to the 0νββ-decay half-life of 2.8 × 1025 years (90% CL) for an exposure of 100 kg·year, or 6.0 × 1025 years after a run of 3 effective years.[Figure not available: see fulltext.]
Published: 2016

9. Sensitivity of NEXT-100 to neutrinoless double beta decay

Author: Martín-Albo, J, Muñoz Vidal, J, Ferrario, P, Nebot-Guinot, M, Gómez-Cadenas, JJ, Álvarez, V, Azevedo, CDR, Borges, FIG, Cárcel, S, Carrión, JV, Cebrián, S, Cervera, A, Conde, CAN, Díaz, J, Diesburg, M, Esteve, R, Fernandes, LMP, Ferreira, AL, Freitas, EDC, Goldschmidt, A, González-Díaz, D, Gutiérrez, RM, Hauptman, J, Henriques, CAO, Hernando Morata, JA, Herrero, V, Labarga, L, Laing, A, Lebrun, P, Liubarsky, I, López-March, N, Lorca, D, Losada, M, Martínez-Lema, G, Martínez, A, Monrabal, F, Monteiro, CMB, Mora, FJ, Moutinho, LM, Novella, P, Nygren, D, Palmeiro, B, Para, A, Querol, M, Renner, J, Ripoll, L, Rodríguez, J, Santos, FP, dos Santos, JMF, Serra, L, Shuman, D, Simón, A, Sofka, C, Sorel, M, Stiegler, T, Toledo, JF, Torrent, J, Tsamalaidze, Z, Veloso, JFCA, Webb, R, White, JT, Yahlali, N, and Yepes-Ramírez, H
Subjects: Nuclear & Particles Physics, Mathematical Physics, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Quantum Physics
Abstract: Abstract: NEXT-100 is an electroluminescent high-pressure xenon gas time projection chamber that will search for the neutrinoless double beta (0νββ) decay of 136Xe. The detector possesses two features of great value for 0νββ searches: energy resolution better than 1% FWHM at the Q value of 136Xe and track reconstruction for the discrimination of signal and background events. This combination results in excellent sensitivity, as discussed in this paper. Material-screening measurements and a detailed Monte Carlo detector simulation predict a background rate for NEXT-100 of at most 4 × 10−4 counts keV−1 kg−1 yr−1. Accordingly, the detector will reach a sensitivity to the 0νββ-decay half-life of 2.8 × 1025 years (90% CL) for an exposure of 100 kg·year, or 6.0 × 1025 years after a run of 3 effective years.[Figure not available: see fulltext.]
Published: 2016

10. An improved measurement of electron-ion recombination in high-pressure xenon gas

Author: NEXT Collaboration, Serra, L., Sorel, M., Álvarez, V., Borges, F. I. G., Camargo, M., Cárcel, S., Cebrián, S., Cervera, A., Conde, C. A. N., Dafni, T., Díaz, J., Esteve, R., Fernandes, L. M. P., Ferrario, P., Ferreira, A. L., Freitas, E. D. C., Gehman, V. M., Goldschmidt, A., Gómez-Cadenas, J. J., González-Díaz, D., Gutiérrez, R. M., Hauptman, J., Morata, J. A. Hernando, Herrera, D. C., Irastorza, I. G., Labarga, L., Laing, A., Liubarsky, I., Lopez-March, N., Lorca, D., Losada, M., Luzón, G., Marí, A., Martín-Albo, J., Martínez-Lema, G., Martínez, A., Miller, T., Monrabal, F., Monserrate, M., Monteiro, C. M. B., Mora, F. J., Moutinho, L. M., Vidal, J. Muñoz, Nebot-Guinot, M., Nygren, D., Oliveira, C. A. B., Pérez, J., Aparicio, J. L. Pérez, Querol, M., Renner, J., Ripoll, L., Rodríguez, A., Rodríguez, J., Santos, F. P., Santos, J. M. F. dos, Shuman, D., Simón, A., Sofka, C., Toledo, J. F., Torrent, J., Tsamalaidze, Z., Veloso, J. F. C. A., Villar, J. A., Webb, R., White, J. T., and Yahlali, N.
Subjects: Physics - Instrumentation and Detectors, High Energy Physics - Experiment
Abstract: We report on results obtained with the NEXT-DEMO prototype of the NEXT-100 high-pressure xenon gas time projection chamber (TPC), exposed to an alpha decay calibration source. Compared to our previous measurements with alpha particles, an upgraded detector and improved analysis techniques have been used. We measure event-by-event correlated fluctuations between ionization and scintillation due to electron-ion recombination in the gas, with correlation coeffcients between -0.80 and -0.56 depending on the drift field conditions. By combining the two signals, we obtain a 2.8 % FWHM energy resolution for 5.49 MeV alpha particles and a measurement of the optical gain of the electroluminescent TPC. The improved energy resolution also allows us to measure the specific activity of the radon in the gas due to natural impurities. Finally, we measure the average ratio of excited to ionized atoms produced in the xenon gas by alpha particles to be $0.561\pm 0.045$, translating into an average energy to produce a primary scintillation photon of $W_{\rm ex}=(39.2\pm 3.2)$ eV., Comment: 22 pages, 11 figures, 1 table
Published: 2014
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11. Radiopurity assessment of the tracking readout for the NEXT double beta decay experiment

Author: Cebrián, S., Pérez, J., Bandac, I., Labarga, L., Álvarez, V., Barrado, A. I., Bettini, A., Borges, F. I. G. M., Camargo, M., Cárcel, S., Cervera, A., Conde, C. A. N., Conde, E., Dafni, T., Díaz, J., Esteve, R., Fernandes, L. M. P., Fernández, M., Ferrario, P., Ferreira, A. L., Freitas, E. D. C., Gehman, V. M., Goldschmidt, A., Gómez-Cadenas, J. J., González-Díaz, D., Gutiérrez, R. M., Hauptman, J., Morata, J. A. Hernando, Herrera, D. C., Irastorza, I. G., Laing, A., Liubarsky, I., López-March, N., Lorca, D., Losada, M., Luzón, G., Marí, A., Martín-Albo, J., Martínez, A., Martínez-Lema, G., Miller, T., Monrabal, F., Monserrate, M., Monteiro, C. M. B., Mora, F. J., Moutinho, L. M., Vidal, J. Muñoz, Nebot-Guinot, M., Nygren, D., Oliveira, C. A. B., de Solórzano, A. Ortiz, Aparicio, J. L. Pérez, Querol, M., Renner, J., Ripoll, L., Rodríguez, J., Santos, F. P., Santos, J. M. F. dos, Serra, L., Shuman, D., Simón, A., Sofka, C., Sorel, M., Toledo, J. F., Torrent, J., Tsamalaidze, Z., Veloso, J. F. C. A., Villar, J. A., Webb, R. C., White, J. T., and Yahlali, N.
Subjects: Physics - Instrumentation and Detectors, High Energy Physics - Experiment, Nuclear Experiment
Abstract: The Neutrino Experiment with a Xenon Time-Projection Chamber (NEXT) is intended to investigate the neutrinoless double beta decay of 136Xe, which requires a severe suppression of potential backgrounds; therefore, an extensive screening and selection process is underway to control the radiopurity levels of the materials to be used in the experimental set-up of NEXT. The detector design combines the measurement of the topological signature of the event for background discrimination with the energy resolution optimization. Separate energy and tracking readout planes are based on different sensors: photomultiplier tubes for calorimetry and silicon multi-pixel photon counters for tracking. The design of a radiopure tracking plane, in direct contact with the gas detector medium, was specially challenging since the needed components like printed circuit boards, connectors, sensors or capacitors have typically, according to available information in databases and in the literature, activities too large for experiments requiring ultra-low background conditions. Here, the radiopurity assessment of tracking readout components based on gamma-ray spectroscopy using ultra-low background germanium detectors at the Laboratorio Subterraneo de Canfranc (Spain) is described. According to the obtained results, radiopure enough printed circuit boards made of kapton and copper, silicon photomultipliers and other required components, fulfilling the requirement of an overall background level in the region of interest of at most 8 10-4 counts keV-1 kg-1 y-1, have been identified.
Published: 2014
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12. Results of the material screening program of the NEXT experiment

Author: Dafni, T., Alvarez, V., Bandac, I., Bettini, A., Borges, F. I. G. M., Camargo, M., Carcel, S., Cebrian, S., Cervera, A., Conde, C. A. N., Diaz, J., Esteve, R., Fernandes, L. M. P., Fernandez, M., Ferrario, P., Ferreira, A. L., Freitas, E. D. C., Gehman, V. M., Goldschmidt, A., Gomez, H., Gomez-Cadenas, J. J., Gonzalez-Diaz, D., Gutierrez, R. M., Hauptman, J., Morata, J. A. Hernando, Herrera, D. C., Iguaz, F. J., Irastorza, I. G., Labarga, L., Laing, A., Liubarsky, I., Lorca, D., Losada, M., Luzon, G., Mari, A., Martin-Albo, J., Martinez, A., Martinez-Lema, G., Miller, T., Monrabal, F., Monserrate, M., Monteiro, C. M. B., Mora, F. J., Moutinho, L. M., Vidal, J. Munoz, Nebot-Guinot, M., Nygren, D., Oliveira, C. A. B., Perez, J., Aparicio, J. L. Perez, Renner, J., Ripoll, L., Rodriguez, A., Rodriguez, J., Santos, F. P., Santos, J. M. F. dos, Segui, L., Serra, L., Shuman, D., Simon, A., Sofka, C., Sorel, M., Toledo, J. F., Torrent, J., Tsamalaidze, Z., Veloso, J. F. C. A., Villar, J. A., Webb, R. C., White, J. T., and Yahlali, N.
Subjects: Physics - Instrumentation and Detectors, High Energy Physics - Experiment, Nuclear Experiment
Abstract: The 'Neutrino Experiment with a Xenon TPC (NEXT)', intended to investigate neutrinoless double beta decay, requires extremely low background levels. An extensive material screening and selection process to assess the radioactivity of components is underway combining several techniques, including germanium gamma-ray spectrometry performed at the Canfranc Underground Laboratory; recent results of this material screening program are presented here., Comment: Proceedings for a poster contribution at ICHEP 2014, Valencia, Spain
Published: 2014

13. Ionization and scintillation of nuclear recoils in gaseous xenon

Author: Renner, J., Gehman, V. M., Goldschmidt, A., Matis, H. S., Miller, T., Nakajima, Y., Nygren, D., Oliveira, C. A. B., Shuman, D., Álvarez, V., Borges, F. I. G., Cárcel, S., Castel, J., Cebrián, S., Cervera, A., Conde, C. A. N., Dafni, T., Dias, T. H. V. T., Díaz, J., Esteve, R., Evtoukhovitch, P., Fernandes, L. M. P., Ferrario, P., Ferreira, A. L., Freitas, E. D. C., Gil, A., Gómez, H., Gómez-Cadenas, J. J., González-Díaz, D., Gutiérrez, R. M., Hauptman, J., Morata, J. A. Hernando, Herrera, D. C., Iguaz, F. J., Irastorza, I. G., Jinete, M. A., Labarga, L., Laing, A., Liubarsky, I., Lopes, J. A. M., Lorca, D., Losada, M., Luzón, G., Marí, A., Martín-Albo, J., Martínez, A., Moiseenko, A., Monrabal, F., Monserrate, M., Monteiro, C. M. B., Mora, F. J., Moutinho, L. M., Vidal, J. Muñoz, da Luz, H. Natal, Navarro, G., Nebot-Guinot, M., Palma, R., Pérez, J., Aparicio, J. L. Pérez, Ripoll, L., Rodríguez, A., Rodríguez, J., Santos, F. P., Santos, J. M. F. dos, Seguí, L., Serra, L., Simón, A., Sofka, C., Sorel, M., Toledo, J. F., Tomás, A., Torrent, J., Tsamalaidze, Z., Veloso, J. F. C. A., Villar, J. A., Webb, R. C., White, J., and Yahlali, N.
Subjects: Physics - Instrumentation and Detectors, High Energy Physics - Experiment, Nuclear Experiment
Abstract: Ionization and scintillation produced by nuclear recoils in gaseous xenon at approximately 14 bar have been simultaneously observed in an electroluminescent time projection chamber. Neutrons from radioisotope $\alpha$-Be neutron sources were used to induce xenon nuclear recoils, and the observed recoil spectra were compared to a detailed Monte Carlo employing estimated ionization and scintillation yields for nuclear recoils. The ability to discriminate between electronic and nuclear recoils using the ratio of ionization to primary scintillation is demonstrated. These results encourage further investigation on the use of xenon in the gas phase as a detector medium in dark matter direct detection experiments., Comment: 15 pages, 14 figures
Published: 2014
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14. Characterisation of NEXT-DEMO using xenon K$_{\alpha}$ X-rays

Author: NEXT Collaboration, Lorca, D., Martín-Albo, J., Laing, A., Ferrario, P., Gómez-Cadenas, J. J., Álvarez, V., Borges, F. I. G., Camargo, M., Cárcel, S., Cebrián, S., Cervera, A., Conde, C. A. N., Dafni, T., Díaz, J., Esteve, R., Fernandes, L. M. P., Ferreira, A. L., Freitas, E. D. C., Gehman, V. M., Goldschmidt, A., Gómez, H., González-Díaz, D., Gutiérrez, R. M., Hauptman, J., Morata, J. A. Hernando, Herrera, D. C., Irastorza, I. G., Labarga, L., Liubarsky, I., Losada, M., Luzón, G., Marí, A., Martínez-Lema, G., Martínez, A., Miller, T., Monrabal, F., Monserrate, M., Monteiro, C. M. B., Mora, F. J., Moutinho, L. M., Vidal, J. Muñoz, Nebot-Guinot, M., Nygren, D., Oliveira, C. A. B., Pérez, J., Aparicio, J. L. Pérez, Renner, J., Ripoll, L., Rodríguez, A., Rodríguez, J., Santos, F. P., Santos, J. M. F. dos, Seguí, L., Serra, L., Shuman, D., Simón, A., Sofka, C., Sorel, M., Toledo, J. F., Torrent, J., Tsamalaidze, Z., Veloso, J. F. C. A., Webb, R., White, J. T., and Yahlali, N.
Subjects: Physics - Instrumentation and Detectors, High Energy Physics - Experiment
Abstract: The NEXT experiment aims to observe the neutrinoless double beta decay of $^{136}$Xe in a high pressure gas TPC using electroluminescence (EL) to amplify the signal from ionization. Understanding the response of the detector is imperative in achieving a consistent and well understood energy measurement. The abundance of xenon k-shell x-ray emission during data taking has been identified as a multitool for the characterisation of the fundamental parameters of the gas as well as the equalisation of the response of the detector. The NEXT-DEMO prototype is a ~1.5 kg volume TPC filled with natural xenon. It employs an array of 19 PMTs as an energy plane and of 256 SiPMs as a tracking plane with the TPC light tube and SiPM surfaces being coated with tetraphenyl butadiene (TPB) which acts as a wavelength shifter for the VUV scintillation light produced by xenon. This paper presents the measurement of the properties of the drift of electrons in the TPC, the effects of the EL production region, and the extraction of position dependent correction constants using K$_{\alpha}$ X-ray deposits. These constants were used to equalise the response of the detector to deposits left by gammas from $^{22}$Na.
Published: 2014
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15. First proof of topological signature in the high pressure xenon gas TPC with electroluminescence amplification for the NEXT experiment

Author: The NEXT collaboration, Ferrario, P, Laing, A, López-March, N, Gómez-Cadenas, JJ, Álvarez, V, Azevedo, CDR, Borges, FIG, Cárcel, S, Cebrián, S, Cervera, A, Conde, CAN, Dafni, T, Díaz, J, Diesburg, M, Esteve, R, Fernandes, LMP, Ferreira, AL, Freitas, EDC, Gehman, VM, Goldschmidt, A, González-Díaz, D, Gutiérrez, RM, Hauptman, J, Henriques, CAO, Hernando Morata, JA, Irastorza, IG, Labarga, L, Lebrun, P, Liubarsky, I, Lorca, D, Losada, M, Luzón, G, Marí, A, Martín-Albo, J, Martínez-Lema, G, Martínez, A, Miller, T, Monrabal, F, Monserrate, M, Monteiro, CMB, Mora, FJ, Moutinho, LM, Muñoz Vidal, J, Nebot-Guinot, M, Novella, P, Nygren, D, Para, A, Pérez, J, Pérez Aparicio, JL, Querol, M, Renner, J, Ripoll, L, Rodríguez, J, Santos, FP, dos Santos, JMF, Serra, L, Shuman, D, Simón, A, Sofka, C, Sorel, M, Toledo, JF, Torrent, J, Tsamalaidze, Z, Veloso, JFCA, Villar, JA, Webb, R, White, JT, Yahlali, N, and Yepes-Ramírez, H
Subjects: Nuclear and Plasma Physics, Particle and High Energy Physics, Physical Sciences, Dark Matter, Double Beta Decay, Mathematical Physics, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Quantum Physics, Nuclear & Particles Physics, Mathematical physics, Nuclear and plasma physics, Particle and high energy physics
Abstract: The NEXT experiment aims to observe the neutrinoless double beta decay of 136Xe in a high-pressure xenon gas TPC using electroluminescence (EL) to amplify the signal from ionization. One of the main advantages of this technology is the possibility to reconstruct the topology of events with energies close to Qββ. This paper presents the first demonstration that the topology provides extra handles to reject background events using data obtained with the NEXT-DEMO prototype. Single electrons resulting from the interactions of 22Na 1275 keV gammas and electronpositron pairs produced by conversions of gammas from the 228Th decay chain were used to represent the background and the signal in a double beta decay. These data were used to develop algorithms for the reconstruction of tracks and the identification of the energy deposited at the end-points, providing an extra background rejection factor of 24.3 ± 1.4 (stat.)%, while maintaining an efficiency of 66.7 ± 1.% for signal events.[Figure not available: see fulltext.]
Published: 2016

16. First proof of topological signature in the high pressure xenon gas TPC with electroluminescence amplification for the NEXT experiment

Author: Ferrario, P, Laing, A, López-March, N, Gómez-Cadenas, JJ, Álvarez, V, Azevedo, CDR, Borges, FIG, Cárcel, S, Cebrián, S, Cervera, A, Conde, CAN, Dafni, T, Díaz, J, Diesburg, M, Esteve, R, Fernandes, LMP, Ferreira, AL, Freitas, EDC, Gehman, VM, Goldschmidt, A, González-Díaz, D, Gutiérrez, RM, Hauptman, J, Henriques, CAO, Hernando Morata, JA, Irastorza, IG, Labarga, L, Lebrun, P, Liubarsky, I, Lorca, D, Losada, M, Luzón, G, Marí, A, Martín-Albo, J, Martínez-Lema, G, Martínez, A, Miller, T, Monrabal, F, Monserrate, M, Monteiro, CMB, Mora, FJ, Moutinho, LM, Muñoz Vidal, J, Nebot-Guinot, M, Novella, P, Nygren, D, Para, A, Pérez, J, Pérez Aparicio, JL, Querol, M, Renner, J, Ripoll, L, Rodríguez, J, Santos, FP, dos Santos, JMF, Serra, L, Shuman, D, Simón, A, Sofka, C, Sorel, M, Toledo, JF, Torrent, J, Tsamalaidze, Z, Veloso, JFCA, Villar, JA, Webb, R, White, JT, Yahlali, N, and Yepes-Ramírez, H
Subjects: Dark Matter, Double Beta Decay, Nuclear & Particles Physics, Mathematical Sciences, Physical Sciences, Mathematical Physics, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Quantum Physics, Atomic, Molecular, Nuclear, Particle and Plasma Physics
Abstract: The NEXT experiment aims to observe the neutrinoless double beta decay of 136Xe in a high-pressure xenon gas TPC using electroluminescence (EL) to amplify the signal from ionization. One of the main advantages of this technology is the possibility to reconstruct the topology of events with energies close to Qββ. This paper presents the first demonstration that the topology provides extra handles to reject background events using data obtained with the NEXT-DEMO prototype. Single electrons resulting from the interactions of 22Na 1275 keV gammas and electronpositron pairs produced by conversions of gammas from the 228Th decay chain were used to represent the background and the signal in a double beta decay. These data were used to develop algorithms for the reconstruction of tracks and the identification of the energy deposited at the end-points, providing an extra background rejection factor of 24.3 ± 1.4 (stat.)%, while maintaining an efficiency of 66.7 ± 1.% for signal events.[Figure not available: see fulltext.]
Published: 2016

17. Characterization of a medium size Xe/TMA TPC instrumented with microbulk Micromegas, using low-energy $\gamma$-rays

Author: The NEXT collaboration, Alvarez, V., Borges, F. I. G. M., Carcel, S., Castel, J., Cebrian, S., Cervera, A., Conde, C. A. N., Dafni, T., Dias, T. H. V. T., Diaz, J., Egorov, M., Esteve, R., Evtoukhovitch, P., Fernandes, L. M. P., Ferrario, P., Ferreira, A. L., Freitas, E. D. C., Gehman, V. M., Gil, A., Goldschmidt, A., Gomez, H., Gomez-Cadenas, J. J., Gonzalez-Diaz, D., Gutierrez, R. M., Hauptman, J., Morata, J. A. Hernando, Herrera, D. C., Iguaz, F. J., Irastorza, I. G., Jinete, M. A., Labarga, L., Laing, A., Liubarsky, I., Lopes, J. A. M., Lorca, D., Losada, M., Luzon, G., Mari, A., Martin-Albo, J., Martinez, A., Martinez-Lema, G., Miller, T., Moiseenko, A., Monrabal, F., Monteiro, C. M. B., Mora, F. J., Moutinho, L. M., Vidal, J. Munoz, da Luz, H. Natal, Navarro, G., Nebot-Guinot, M., Nygren, D., Oliveira, C. A. B., Palma, R., Perez, J., Aparicio, J. L. Perez, Renner, J., Ripoll, L., Rodriguez, A., Rodriguez, J., Santos, F. P., Santos, J. M. F. dos, Segui, L., Serra, L., Shuman, D., Simon, A., Sofka, C., Sorel, M., Toledo, J. F., Tomas, A., Torrent, J., Tsamalaidze, Z., Vazquez, D., Veloso, J. F. C. A., Villar, J. A., Webb, R. C., White, J. T., Yahlali, N., Aznar, F., Calvet, D., Druillole, F., Ferrer-Ribas, E., Garcia, J. A., Giomataris, I., Gracia, J., Coguie, A. Le, Mols, J. P., Pons, P., and Ruiz, E.
Subjects: Physics - Instrumentation and Detectors
Abstract: NEXT-MM is a general-purpose high pressure (10 bar, $\sim25$ l active volume) Xenon-based TPC, read out in charge mode with an 8 cm $\times$8 cm-segmented 700 cm$^2$ plane (1152 ch) of the latest microbulk-Micromegas technology. It has been recently commissioned at University of Zaragoza as part of the R&D of the NEXT $0\nu\beta\beta$ experiment, although the experiment's first stage is currently being built based on a SiPM/PMT-readout concept relying on electroluminescence. Around 2 million events were collected during the last months, stemming from the low energy $\gamma$-rays emitted by a $^{241}$Am source when interacting with the Xenon gas ($\epsilon$ = 26, 30, 59.5 keV). The localized nature of such events above atmospheric pressure, the long drift times, as well as the possibility to determine their production time from the associated $\alpha$ particle in coincidence, allow the extraction of primordial properties of the TPC filling gas, namely the drift velocity, diffusion and attachment coefficients. In this work we focus on the little explored combination of Xe and trimethylamine (TMA) for which, in particular, such properties are largely unknown. This gas mixture offers potential advantages over pure Xenon when aimed at Rare Event Searches, mainly due to its Penning characteristics, wave-length shifting properties and reduced diffusion, and it is being actively investigated by our collaboration. The chamber is currently operated at 2.7 bar, as an intermediate step towards the envisaged 10 bar. We report here its performance as well as a first implementation of the calibration procedures that have allowed the extension of the previously reported energy resolution to the whole readout plane (10.6%FWHM@30keV)., Comment: 22 pages, 13 figures
Published: 2013
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18. Description and commissioning of NEXT-MM prototype: first results from operation in a Xenon-Trimethylamine gas mixture

Author: NEXT Collaboration, Álvarez, V., Aznar, F., Borges, F. I. G. M., Calvet, D., Cárcel, S., Castel, J., Cebrián, S., Cervera, A., Conde, C. A. N., Dafni, T., Dias, T. H. V. T., Díaz, J., Druillole, F., Egorov, M., Esteve, R., Evtoukhovitch, P., Fernandes, L. M. P., Ferrario, P., Ferreira, A. L., Ferrer-Ribas, E., Freitas, E. D. C., Gehman, V. M., Gil, A., Giomataris, I., Goldschmidt, A., Gómez, H., Gómez-Cadenas, J. J., González-Díaz, D., Gutiérrez, R. M., Hauptman, J., Morata, J. A. Hernando, Herrera, D. C., Iguaz, F. J., Irastorza, I. G., Jinete, M. A., Labarga, L., Laing, A., Coguie, A. Le, Liubarsky, I., Lopes, J. A. M., Lorca, D., Losada, M., Luzón, G., Marí, A., Martín-Albo, J., Martínez, A., Martínez-Lema, G., Miller, T., Moiseenko, A., Mols, J. P., Monrabal, F., Monteiro, C. M. B., Mora, F. J., Moutinho, L. M., Vidal, J. Muñoz, da Luz, H. Natal, Navarro, G., Nebot-Guinot, M., Nygren, D., Oliveira, C. A. B., Palma, R., Pérez, J., Aparicio, J. L. Pérez, Renner, J., Ripoll, L., Rodríguez, A., Rodríguez, J., Santos, P., Santos, J. M. F. dos, Segui, L., Serra, L., Shuman, D., Simón, A., Sofka, C., Sorel, M., Toledo, J. F., Tomás, A., Torrent, J., Tsamalaidze, Z., Veloso, J. F. C. A., Villar, J. A., Webb, R. C., White, J. T., and Yahlali, N.
Subjects: Physics - Instrumentation and Detectors
Abstract: A technical description of NEXT-MM and its commissioning and first performance is reported. Having an active volume of ~35 cm drift $\times$ 28 cm diameter, it constitutes the largest Micromegas-read TPC operated in Xenon ever constructed, made by a sectorial arrangement of the 4 largest single wafers manufactured with the Microbulk technique to date. It is equipped with a suitably pixelized readout and with a sufficiently large sensitive volume (~23 l) so as to contain long (~20 cm) electron tracks. First results obtained at 1 bar for Xenon and trimethylamine (Xe-(2 %)TMA) mixture are presented. The TPC can accurately reconstruct extended background tracks. An encouraging full-width half-maximum of 11.6 % was obtained for ~29 keV gammas without resorting to any data post-processing., Comment: 22 pages, 9 figures
Published: 2013
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19. Present status and future perspectives of the NEXT experiment

Author: The NEXT Collaboration, Gómez-Cadenas, J. J., Álvarez, V., Borges, F. I. G. M., Cárcel, S., Castel, J., Cebrián, S., Cervera, A., Conde, C. A. N., Dafni, T., Dias, T. H. V. T., Díaz, J., Egorov, M., Esteve, R., Evtoukhovitch, P., Fernandes, L. M. P., Ferrario, P., Ferreira, A. L., Freitas, E. D. C., Gehman, V. M., Gil, A., Goldschmidt, A., Gómez, H., González-Díaz, D., Gutiérrez, R. M., Hauptman, J., Morata, J. A. Hernando, Herrera, D. C., Iguaz, F. J., Irastorza, I. G., Jinete, M. A., Labarga, L., Laing, A., Liubarsky, I., Lopes, J. A. M., Lorca, D., Losada, M., Luzón, G., Marí, A., Martín-Albo, J., Martínez, A., Miller, T., Moiseenko, A., Monrabal, F., Monteiro, C. M. B., Mora, F. J., Moutinho, L. M., Vidal, J. Muñoz, da Luz, H. Natal, Navarro, G., Nebot-Guinot, M., Nygren, D., Oliveira, C. A. B., Palma, R., Pérez, J., Aparicio, J. L. Pérez, Renner, J., Ripoll, L., Rodríguez, A., Rodríguez, J., Santos, F. P., Santos, J. M. F. dos, Segui, L., Serra, L., Shuman, D., Simón, A., Sofka, C., Sorel, M., Toledo, J. F., Tomás, A., Torrent, J., Tsamalaidze, Z., Veloso, J. F. C. A., Villar, J. A., Webb, R. C., White, J., and Yahlali, N.
Subjects: Physics - Instrumentation and Detectors
Abstract: NEXT is an experiment dedicated to neutrinoless double beta decay searches in xenon. The detector is a TPC, holding 100 kg of high-pressure xenon enriched in the $^{136}$Xe isotope. It is under construction in the Laboratorio Subterr\'aneo de Canfranc in Spain, and it will begin operations in 2015. The NEXT detector concept provides an energy resolution better than 1% FWHM and a topological signal that can be used to reduce the background. Furthermore, the NEXT technology can be extrapolated to a 1-ton scale experiment., Comment: Submitted to Advances in High Energy Physics, Special Issue
Published: 2013

20. Operation and first results of the NEXT-DEMO prototype using a silicon photomultiplier tracking array

Author: The NEXT Collaboration, Álvarez, V., Borges, F. I. G., Cárcel, S., Castel, J., Cebrián, S., Cervera, A., Conde, C. A. N., Dafni, T., Dias, T. H. V. T., Díaz, J., Egorov, M., Esteve, R., Evtoukhovitch, P., Fernandes, L. M. P., Ferrario, P., Ferreira, A. L., Freitas, E. D. C., Gehman, V. M., Gil, A., Goldschmidt, A., Gómez, H., Gómez-Cadenas, J. J., González-Díaz, D., Gutiérrez, R. M., Hauptman, J., Morata, J. A. Hernando, Herrera, D. C., Iguaz, F. J., Irastorza, I. G., Jinete, M. A., Labarga, L., Laing, A., Liubarsky, I., Lopes, J. A. M., Lorca, D., Losada, M., Luzón, G., Marí, A., Martín-Albo, J., Martínez, A., Martínez, G., Miller, T., Moiseenko, A., Monrabal, F., Monteiro, C. M. B., Mora, F. J., Moutinho, L. M., Vidal, J. Muñoz, da Luz, H. Natal, Navarro, G., Nebot-Guinot, M., Nygren, D., Oliveira, C. A. B., Palma, R., Pérez, J., Aparicio, J. L. Pérez, Renner, J., Ripoll, L., Rodríguez, A., Rodríguez, J., Santos, F. P., Santos, J. M. F. dos, Seguí, L., Serra, L., Shuman, D., Simón, A., Sofka, C., Sorel, M., Toledo, J. F., Tomás, A., Torrent, J., Tsamalaidze, Z., Veloso, J. F. C. A., Villar, J. A., Webb, R., White, J. T., and Yahlali, N.
Subjects: Physics - Instrumentation and Detectors
Abstract: NEXT-DEMO is a high-pressure xenon gas TPC which acts as a technological test-bed and demonstrator for the NEXT-100 neutrinoless double beta decay experiment. In its current configuration the apparatus fully implements the NEXT-100 design concept. This is an asymmetric TPC, with an energy plane made of photomultipliers and a tracking plane made of silicon photomultipliers (SiPM) coated with TPB. The detector in this new configuration has been used to reconstruct the characteristic signature of electrons in dense gas. Demonstrating the ability to identify the MIP and "blob" regions. Moreover, the SiPM tracking plane allows for the definition of a large fiducial region in which an excellent energy resolution of 1.82% FWHM at 511 keV has been measured (a value which extrapolates to 0.83% at the xenon Qbetabeta)., Comment: 20 pages, 17 figures. This version: corrected typos, updated acknowledgements. Ready for submission to the Journal of Instrumentation (JINST)
Published: 2013
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21. Initial results of NEXT-DEMO, a large-scale prototype of the NEXT-100 experiment

Author: NEXT Collaboration, Álvarez, V., Borges, F. I. G. M., Cárcel, S., Castel, J., Cebrián, S., Cervera, A., Conde, C. A. N., Dafni, T., Dias, T. H. V. T., Díaz, J., Egorov, M., Esteve, R., Evtoukhovitch, P., Fernandes, L. M. P., Ferrario, P., Ferreira, A. L., Freitas, E. D. C., Gehman, V. M., Gil, A., Goldschmidt, A., Gómez, H., Gómez-Cadenas, J. J., González-Díaz, D., Gutiérrez, R. M., Hauptman, J., Morata, J. A. Hernando, Herrera, D. C., Iguaz, F. J., Irastorza, I. G., Jinete, M. A., Labarga, L., Laing, A., Liubarsky, I., Lopes, J. A. M., Lorca, D., Losada, M., Luzón, G., Marí, A., Martín-Albo, J., Martínez, A., Miller, T., Moiseenko, A., Monrabal, F., Monteiro, C. M. B., Mora, F. J., Moutinho, L. M., Vidal, J. Muñoz, da Luz, H. Natal, Navarro, G., Nebot-Guinot, M., Nygren, D., Oliveira, C. A. B., Palma, R., Pérez, J., Aparicio, J. L. Pérez, Renner, J., Ripoll, L., Rodríguez, A., Rodríguez, J., Santos, F. P., Santos, J. M. F. dos, Segui, L., Serra, L., Shuman, D., Simón, A., Sofka, C., Sorel, M., Toledo, J. F., Tomás, A., Torrent, J., Tsamalaidze, Z., Vázquez, D., Veloso, J. F. C. A., Villar, J. A., Webb, R., White, J. T, and Yahlali, N.
Subjects: Physics - Instrumentation and Detectors
Abstract: NEXT-DEMO is a large-scale prototype of the NEXT-100 detector, an electroluminescent time projection chamber that will search for the neutrinoless double beta decay of Xe-136 using 100 to 150 kg of enriched xenon gas. NEXT-DEMO was built to prove the expected performance of NEXT-100, namely, energy resolution better than 1% FWHM at 2.5 MeV and event topological reconstruction. In this paper we describe the prototype and its initial results. A resolution of 1.75% FWHM at 511 keV (which extrapolates to 0.8% FWHM at 2.5 MeV) was obtained at 10 bar pressure using a gamma-ray calibration source. Also, a basic study of the event topology along the longitudinal coordinate is presented, proving that it is possible to identify the distinct dE/dx of electron tracks in high-pressure xenon using an electroluminescence TPC., Comment: 23 pages, 22 figures. Version accepted for publication by the Journal of Instrumentation (JINST)
Published: 2012
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22. Near-Intrinsic Energy Resolution for 30 to 662 keV Gamma Rays in a High Pressure Xenon Electroluminescent TPC

Author: NEXT Collaboration, Álvarez, V., Borges, F. I. G. M., Cárcel, S., Castel, J., Cebrián, S., Cervera, A., Conde, C. A. N., Dafni, T., Dias, T. H. V. T., Díaz, J., Egorov, M., Esteve, R., Evtoukhovitch, P., Fernandes, L. M. P., Ferrario, P., Ferreira, A. L., Freitas, E. D. C., Gehman, V. M., Gil, A., Goldschmidt, A., Gómez, H., Gómez-Cadenas, J. J., González-Díaz, D., Gutiérrez, R. M., Hauptman, J., Morata, J. A. Hernando, Herrera, D. C., Iguaz, F. J., Irastorza, I. G., Jinete, M. A., Labarga, L., Laing, A., Liubarsky, I., Lopes, J. A. M., Lorca, D., Losada, M., Luzón, G., Marí, A., Martín-Albo, J., Martínez, A., Miller, T., Moiseenko, A., Monrabal, F., Monteiro, C. M. B., Mora, F. J., Moutinho, L. M., Vidal, J. Muñoz, da Luz, H. Natal, Navarro, G., Nebot, M., Nygren, D., Oliveira, C. A. B., Palma, R., Pérez, J., Aparicio, J. L. Pérez, Renner, J., Ripoll, L., Rodríguez, A., Rodríguez, J., Santos, F. P., Santos, J. M. F. dos, Segui, L., Serra, L., Shuman, D., Simón, A., Sofka, C., Sorel, M., Toledo, J. F., Tomás, A., Torrent, J., Tsamalaidze, Z., Vázquez, D., Veloso, J. F. C. A., Villar, J. A., Webb, R., White, J. T, and Yahlali, N.
Subjects: Physics - Instrumentation and Detectors, High Energy Physics - Experiment, Nuclear Experiment
Abstract: We present the design, data and results from the NEXT prototype for Double Beta and Dark Matter (NEXT-DBDM) detector, a high-pressure gaseous natural xenon electroluminescent time projection chamber (TPC) that was built at the Lawrence Berkeley National Laboratory. It is a prototype of the planned NEXT-100 $^{136}$Xe neutrino-less double beta decay ($0\nu\beta\beta$) experiment with the main objectives of demonstrating near-intrinsic energy resolution at energies up to 662 keV and of optimizing the NEXT-100 detector design and operating parameters. Energy resolutions of $\sim$1% FWHM for 662 keV gamma rays were obtained at 10 and 15 atm and $\sim$5% FWHM for 30 keV fluorescence xenon X-rays. These results demonstrate that 0.5% FWHM resolutions for the 2,459 keV hypothetical neutrino-less double beta decay peak are realizable. This energy resolution is a factor 7 to 20 better than that of the current leading $0\nu\beta\beta$ experiments using liquid xenon and thus represents a significant advancement. We present also first results from a track imaging system consisting of 64 silicon photo-multipliers recently installed in NEXT-DBDM that, along with the excellent energy resolution, demonstrates the key functionalities required for the NEXT-100 $0\nu\beta\beta$ search., Comment: 51 pages, 26 figures
Published: 2012

23. In-situ calibration of a PMT inside a scintillation detector by means of primary scintillation detection

Author: NEXT Collaboration, Álvarez, V., Borges, F. I. G. M., Cárcel, S., Castel, J., Cebrián, S., Cervera, A., Conde, C. A. N., Dafni, T., Dias, T. H. V. T., Díaz, J., Egorov, M., Esteve, R., Evtoukhovitch, P., Fernandes, L. M. P., Ferrario, P., Ferreira, A. L., Freitas, E. D. C., Gehman, V. M., Gil, A., Goldschmidt, A., Gómez, H., Gómez-Cadenas, J. J., González-Díaz, D., Gutiérrez, R. M., Hauptman, J., Morata, J. A. Hernando, Herrera, D. C., Iguaz, F. J., Irastorza, I. G., Jinete, M. A., Labarga, L., Laing, A., Liubarsky, I., Lopes, J. A. M., Lorca, D., Losada, M., Luzón, G., Marí, A., Martín-Albo, J., Martínez, A., Miller, T., Moiseenko, A., Monrabal, F., Monteiro, C. M. B., Mora, F. J., Moutinho, L. M., Vidal, J. Muñoz, da Luz, H. Natal, Navarro, G., Nebot, M., Nygren, D., Oliveira, C. A. B., Palma, R., Pérez, J., Aparicio, J. L. Pérez, Renner, J., Ripoll, L., Rodríguez, A., Rodríguez, J., Santos, F. P., Santos, J. M. F. dos, Segui, L., Serra, L., Shuman, D., Simón, A., Sofka, C., Sorel, M., Toledo, J. F., Tomás, A., Torrent, J., Tsamalaidze, Z., Vázquez, D., Veloso, J. F. C. A., Villar, J. A., Webb, R. C., White, J. T, and Yahlali, N.
Subjects: Physics - Instrumentation and Detectors, High Energy Physics - Experiment
Abstract: We have investigated the possibility of calibrating the PMTs of scintillation detectors, using the primary scintillation produced by X-rays to induce single photoelectron response of the PMT. The high-energy tail of this response, can be approximated to an exponential function, under some conditions. In these cases, it is possible to determine the average gain for each PMT biasing voltage from the inverse of the exponent of the exponential fit to the tail, which can be done even if the background and/or noise cover-up most of the distribution. We have compared our results with those obtained by the commonly used single electron response (SER) method, which uses a LED to induce a single photoelectron response of the PMT and determines the peak position of such response, relative to the pedestal peak (the electronic noise peak, which corresponds to 0 photoelectrons). The results of the exponential fit method agree with those obtained by the SER method when the average number of photoelectrons reaching the first dynode per light/scintillation pulse is around 1.0. The SER method has higher precision, while the exponential fit method has the advantage of being useful in situations where the PMT is already in situ, being difficult or even impossible to apply the SER method, e.g. in sealed scintillator/PMT devices., Comment: 11 pages, 8 figures
Published: 2012

24. Ionization and scintillation response of high-pressure xenon gas to alpha particles

Author: NEXT Collaboration, Álvarez, V., Borges, F. I. G. M., Cárcel, S., Cebrián, S., Cervera, A., Conde, C. A. N., Dafni, T., Díaz, J., Egorov, M., Esteve, R., Evtoukhovitch, P., Fernandes, L. M. P., Ferrario, P., Ferreira, A. L., Freitas, E. D. C., Gehman, V. M., Gil, A., Goldschmidt, A., Gómez, H., Gómez-Cadenas, J. J., González-Díaz, D., Gutiérrez, R. M., Hauptman, J., Morata, J. A. Hernando, Herrera, D. C., Irastorza, I. G., Jinete, M. A., Labarga, L., Laing, A., Liubarsky, I., Lopes, J. A. M., Lorca, D., Losada, M., Luzón, G., Marí, A., Martín-Albo, J., Miller, T., Moiseenko, A., Monrabal, F., Monteiro, C. M. B., Mora, F. J., Moutinho, L. M., Vidal, J. Muñoz, da Luz, H. Natal, Navarro, G., Nebot-Guinot, M., Nygren, D., Oliveira, C. A. B., Palma, R., Pérez, J., Aparicio, J. L. Pérez, Renner, J., Ripoll, L., Rodríguez, A., Rodríguez, J., Santos, F. P., Santos, J. M. F. dos, Segui, L., Serra, L., Shuman, D., Simón, A., Sofka, C., Sorel, M., Toledo, J. F., Tomás, A., Torrent, J., Tsamalaidze, Z., Vázquez, D., Veloso, J. F. C. A., Webb, R., White, J. T, and Yahlali, N.
Subjects: Physics - Instrumentation and Detectors, Astrophysics - Instrumentation and Methods for Astrophysics, High Energy Physics - Experiment, Nuclear Experiment
Abstract: High-pressure xenon gas is an attractive detection medium for a variety of applications in fundamental and applied physics. In this paper we study the ionization and scintillation detection properties of xenon gas at 10 bar pressure. For this purpose, we use a source of alpha particles in the NEXT-DEMO time projection chamber, the large scale prototype of the NEXT-100 neutrinoless double beta decay experiment, in three different drift electric field configurations. We measure the ionization electron drift velocity and longitudinal diffusion, and compare our results to expectations based on available electron scattering cross sections on pure xenon. In addition, two types of measurements addressing the connection between the ionization and scintillation yields are performed. On the one hand we observe, for the first time in xenon gas, large event-by-event correlated fluctuations between the ionization and scintillation signals, similar to that already observed in liquid xenon. On the other hand, we study the field dependence of the average scintillation and ionization yields. Both types of measurements may shed light on the mechanism of electron-ion recombination in xenon gas for highly-ionizing particles. Finally, by comparing the response of alpha particles and electrons in NEXT-DEMO, we find no evidence for quenching of the primary scintillation light produced by alpha particles in the xenon gas., Comment: 36 pages, 19 figures, 5 tables. Version accepted for publication in JINST
Published: 2012
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25. Radiopurity control in the NEXT-100 double beta decay experiment: procedures and initial measurements

Author: Alvarez, V., Bandac, I., Bettini, A., Borges, F. I. G. M., Carcel, S., Castel, J., Cebrian, S., Cervera, A., Conde, C. A. N., Dafni, T., Dias, T. H. V. T., Diaz, J., Egorov, M., Esteve, R., Evtoukhovitch, P., Fernandes, L. M. P., Ferrario, P., Ferreira, A. L., Freitas, E. D. C., Gehman, V. M., Gil, A., Goldschmidt, A., Gomez, H., Gomez-Cadenas, J. J., Gonzalez-Diaz, D., Gutierrez, R. M., Hauptman, J., Morata, J. A. Hernando, Herrera, D. C., Iguaz, F. J., Irastorza, I. G., Jinete, M. A., Labarga, L., Laing, A., Liubarsky, I., Lopes, J. A. M., Lorca, D., Losada, M., Luzon, G., Mari, A., Martin-Albo, J., Martinez, A., Miller, T., Moiseenko, A., Monrabal, F., Monteiro, C. M. B., Mora, F. J., Moutinho, L. M., Vidal, J. Munoz, da Luz, H. Natal, Navarro, G., Nebot, M., Nygren, D., Oliveira, C. A. B., de Solorzano, A. Ortiz, Palma, R., Perez, J., Aparicio, J. L. Perez, Renner, J., Ripoll, L., Rodriguez, A., Rodriguez, J., Santos, F. P., Santos, J. M. F. dos, Segui, L., Serra, L., Shuman, D., Simon, A., Sofka, C., Sorel, M., Toledo, J. F., Tomas, A., Torrent, J., Tsamalaidze, Z., Vazquez, D., Veloso, J. F. C. A., Villar, J. A., Webb, R. C., White, J. T., and Yahlali, N.
Subjects: Physics - Instrumentation and Detectors, Nuclear Experiment
Abstract: The Neutrino Experiment with a Xenon TPC (NEXT) is intended to investigate the neutrinoless double beta decay of 136Xe, which requires a severe suppression of potential backgrounds. An extensive screening and material selection process is underway for NEXT since the control of the radiopurity levels of the materials to be used in the experimental set-up is a must for rare event searches. First measurements based on Glow Discharge Mass Spectrometry and gamma-ray spectroscopy using ultra-low background germanium detectors at the Laboratorio Subterr\'aneo de Canfranc (Spain) are described here. Activity results for natural radioactive chains and other common radionuclides are summarized, being the values obtained for some materials like copper and stainless steel very competitive. The implications of these results for the NEXT experiment are also discussed., Comment: Final version
Published: 2012
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26. Design and characterization of the SiPM tracking system of NEXT-DEMO, a demonstrator prototype of the NEXT-100 experiment

Author: NEXT Collaboration, Álvarez, V., Ball, M., Borges, F. I. G. M., Cárcel, S., Carmona, J. M., Castel, J., Catalá, J. M., Cebrián, S., Cervera, A., Chan, D., Conde, C. A. N., Dafni, T., Dias, T. H. V. T., Díaz, J., Egorov, M., Esteve, R., Evtoukhovitch, P., Fernandes, L. M. P., Ferrario, P., Ferreira, A. L., Ferrer-Ribas, E., Freitas, E. D. C., Garcia, A. N. C., Gehman, V. M., Gil, A., Giomataris, I., Goldschmidt, A., Gómez, H., Gómez-Cadenas, J. J., González, K., González-Díaz, D., Gutiérrez, R. M., Hauptman, J., Morata, J. A. Hernando, Herrera, D. C., Herrero, V., Iguaz, F. J., Irastorza, I. G., Kalinnikov, V., Kiang, D., Labarga, L., Liubarsky, I., Lopes, J. A. M., Lorca, D., Losada, M., Luzón, G., Marí, A., Martín-Albo, J., Martínez, A., Miller, T., Moiseenko, A., Monrabal, F., Monteiro, C. M. B., Monzó, J. M., Mora, F. J., Moutinho, L. M., Vidal, J. Muñoz, da Luz, H. Natal, Navarro, G., Nebot, M., Nygren, D., Oliveira, C. A. B., Palma, R., Pérez, J., Aparicio, J. L. Pérez, Renner, J., Ripoll, L., Rodríguez, A., Rodríguez, J., Santos, F. P., Santos, J. M. F. dos, Segui, L., Serra, L., Shuman, D., Sofka, C., Sorel, M., Toledo, J. F., Tomás, A., Torrent, J., Tsamalaidze, Z., Vázquez, D., Velicheva, E., Veloso, J. F. C. A., Villar, J. A., Webb, R. C., Weber, T., White, J., and Yahlali, N.
Subjects: Physics - Instrumentation and Detectors, High Energy Physics - Experiment
Abstract: NEXT-100 experiment aims at searching the neutrinoless double-beta decay of the Xe-136 isotope using a TPC filled with a 100 kg of high-pressure gaseous xenon, with 90% isotopic enrichment. The experiment will take place at the Laboratorio Subterr\'aneo de Canfranc (LSC), Spain. NEXT-100 uses electroluminescence (EL) technology for energy measurement with a resolution better than 1% FWHM. The gaseous xenon in the TPC additionally allows the tracks of the two beta particles to be recorded, which are expected to have a length of up to 30 cm at 10 bar pressure. The ability to record the topological signature of the neutrinoless double-beta events provides a powerful background rejection factor for the double-beta experiment. In this paper, we present a novel 3D imaging concept using SiPMs coated with tetraphenyl butadiene (TPB) for the EL read out and its first implementation in NEXT-DEMO, a large-scale prototype of the NEXT-100 experiment. The design and the first characterization measurements of the NEXT-DEMO SiPM tracking system are presented. The SiPM response uniformity over the tracking plane drawn from its gain map is shown to be better than 4%. An automated active control system for the stabilization of the SiPMs gain was developed, based on the voltage supply compensation of the gain drifts. The gain is shown to be stabilized within 0.2% relative variation around its nominal value, provided by Hamamatsu, in a temperature range of 10 degree C. The noise level from the electronics and the SiPM dark noise is shown to lay typically below the level of 10 photoelectrons (pe) in the ADC. Hence, a detection threshold at 10 pe is set for the acquisition of the tracking signals. The ADC full dynamic range (4096 channels) is shown to be adequate for signal levels of up to 200 pe/microsecond, which enables recording most of the tracking signals., Comment: Submitted to JINST
Published: 2012

27. NEXT-100 Technical Design Report (TDR). Executive Summary

Author: NEXT Collaboration, Álvarez, V., Borges, F. I. G. M., Cárcel, S., Carmona, J. M., Castel, J., Catalá, J. M., Cebrián, S., Cervera, A., Chan, D., Conde, C. A. N., Dafni, T., Dias, T. H. V. T., Díaz, J., Egorov, M., Esteve, R., Evtoukhovitch, P., Fernandes, L. M. P., Ferrario, P., Ferreira, A. L., Ferrer-Ribas, E., Freitas, E. D. C., Gehman, V. M., Gil, A., Giomataris, I., Goldschmidt, A., Gómez, H., Gómez-Cadenas, J. J., González, K., González-Díaz, D., Gutiérrez, R. M., Hauptman, J., Morata, J. A. Hernando, Herrera, D. C., Herrero, V., Iguaz, F. J., Irastorza, I. G., Kalinnikov, V., Kiang, D., Labarga, L., Liubarsky, I., Lopes, J. A. M., Lorca, D., Losada, M., Luzón, G., Marí, A., Martín-Albo, J., Martínez, A., Miller, T., Moiseenko, A., Monrabal, F., Monteiro, C. M. B., Monzó, J. M., Mora, F. J., Moutinho, L. M., Vidal, J. Muñoz, da Luz, H. Natal, Navarro, G., Nebot, M., Nygren, D., Oliveira, C. A. B., Palma, R., Pérez, J., Aparicio, J. L. Pérez, Renner, J., Ripoll, L., Rodríguez, A., Rodríguez, J., Santos, F. P., Santos, J. M. F. dos, Segui, L., Serra, L., Shuman, D., Sofka, C., Sorel, M., Toledo, J. F., Tomás, A., Torrent, J., Tsamalaidze, Z., Vázquez, D., Velicheva, E., Veloso, J. F. C. A., Villar, J. A., Webb, R. C., Weber, T., White, J., and Yahlali, N.
Subjects: Physics - Instrumentation and Detectors, High Energy Physics - Experiment
Abstract: In this Technical Design Report (TDR) we describe the NEXT-100 detector that will search for neutrinoless double beta decay (bbonu) in Xe-136 at the Laboratorio Subterraneo de Canfranc (LSC), in Spain. The document formalizes the design presented in our Conceptual Design Report (CDR): an electroluminescence time projection chamber, with separate readout planes for calorimetry and tracking, located, respectively, behind cathode and anode. The detector is designed to hold a maximum of about 150 kg of xenon at 15 bar, or 100 kg at 10 bar. This option builds in the capability to increase the total isotope mass by 50% while keeping the operating pressure at a manageable level. The readout plane performing the energy measurement is composed of Hamamatsu R11410-10 photomultipliers, specially designed for operation in low-background, xenon-based detectors. Each individual PMT will be isolated from the gas by an individual, pressure resistant enclosure and will be coupled to the sensitive volume through a sapphire window. The tracking plane consists in an array of Hamamatsu S10362-11-050P MPPCs used as tracking pixels. They will be arranged in square boards holding 64 sensors (8 times8) with a 1-cm pitch. The inner walls of the TPC, the sapphire windows and the boards holding the MPPCs will be coated with tetraphenyl butadiene (TPB), a wavelength shifter, to improve the light collection., Comment: 32 pages, 22 figures, 5 tables
Published: 2012
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28. SiPMs coated with TPB : coating protocol and characterization for NEXT

Author: Álvarez, V., Agramunt, J., Ball, M., Batallé, M., Bayarri, J., Borges, F. I. G., Bolink, H., Brine, H., Cárcel, S., Carmona, J. M., Castel, J., Catalá, J. M., Cebrián, S., Cervera, A., Chan, D., Conde, C. A. N., Dafni, T., Dias, T. H. V. T., Díaz, J., Esteve, R., Evtoukhovitch, P., Ferrando, J., Fernandes, L. M. P., Ferrario, P., Ferreira, A. L., Ferrer-Ribas, E., Freitas, E. D. C., García, S. A., Gil, A., Giomataris, I., Goldschmidt, A., Gómez, E., Gómez, H., Gómez-Cadenas, J. J., González, K., Gutiérrez, R. M., Hauptman, J., Hernando-Morata, J. A., Herrera, D. C., Herrero, V., Iguaz, F. J., Irastorza, I. G., Kalinnikov, V., Labarga, L., Liubarsky, I., Lopes, J. A. M., Lorca, D., Losada, M., Luzón, G., Marí, A., Martin-Albo, J., Méndez, A. M., Miller, T., Moisenko, A., Monrabal, F., Monteiro, C. M. B., Monzó, J. M., Mora, F. J., Vidal, J. Muñoz, da Luz, H. Natal, Navarro, G., Nebot, M., Nygren, D., Oliveira, C. A. B., Palma, R., Aparicio, J. L. Pérez, Pérez, J., Radicioni, E., Quinto, M., Renner, J., Ripoll, L., Rodriguez, A., Rodriguez, J., Santos, F. P., Santos, J. M. F. dos, Seguí, L., Serra, L., Shuman, D., Sofka, C., Sorel, M., Soriano, A., Spieler, H., Toledo, J. F., Collell, J. Torrent, Tomás, A., Tsamalaidze, Z., Vázquez, D., Velicheva, E., Veloso, J. F. C. A., Villar, J. A., Webb, R., Weber, T., White, J. T., and Yahlali, N.
Subjects: Physics - Instrumentation and Detectors, High Energy Physics - Experiment
Abstract: Silicon photomultipliers (SiPM) are the photon detectors chosen for the tracking readout in NEXT, a neutrinoless {\beta}{\beta} decay experiment which uses a high pressure gaseous xenon time projection chamber (TPC). The reconstruction of event track and topology in this gaseous detector is a key handle for background rejection. Among the commercially available sensors that can be used for tracking, SiPMs offer important advantages, mainly high gain, ruggedness, cost-effectiveness and radio-purity. Their main drawback, however, is their non sensitivity in the emission spectrum of the xenon scintillation (peak at 175 nm). This is overcome by coating these sensors with the organic wavelength shifter tetraphenyl butadienne (TPB). In this paper we describe the protocol developed for coating the SiPMs with TPB and the measurements performed for characterizing the coatings as well as the performance of the coated sensors in the UV-VUV range., Comment: Submitted to the Journal of Instrumentation on december 26th 2011
Published: 2012
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29. Present Status and Future Perspectives of the NEXT Experiment

Author: Cadenas, JJ Gómez, Álvarez, V, Borges, FIG, Cárcel, S, Castel, J, Cebrián, S, Cervera, A, Conde, CAN, Dafni, T, Dias, THVT, Díaz, J, Egorov, M, Esteve, R, Evtoukhovitch, P, Fernandes, LMP, Ferrario, P, Ferreira, AL, Freitas, EDC, Gehman, VM, Gil, A, Goldschmidt, A, Gómez, H, González-Díaz, D, Gutiérrez, RM, Hauptman, J, Morata, JA Hernando, Herrera, DC, Iguaz, FJ, Irastorza, IG, Jinete, MA, Labarga, L, Laing, A, Liubarsky, I, Lopes, JAM, Lorca, D, Losada, M, Luzón, G, Marí, A, Martín-Albo, J, Martínez, A, Miller, T, Moiseenko, A, Monrabal, F, Monserrate, M, Monteiro, CMB, Mora, FJ, Moutinho, LM, Vidal, J Muñoz, da Luz, H Natal, Navarro, G, Nebot-Guinot, M, Nygren, D, Oliveira, CAB, Palma, R, Pérez, Javier, Pérez-Aparicio, JL, Renner, J, Ripoll, L, Rodríguez, A, Rodríguez, J, Santos, FP, dos Santos, JMF, Seguí, L, Serra, L, Shuman, D, Simón, A, Sofka, C, Sorel, M, Toledo, JF, Tomás, A, Torrent, J, Tsamalaidze, Z, Veloso, JFCA, Villar, JA, Webb, R, White, J, and Yahlali, N
Subjects: Nuclear and Plasma Physics, Particle and High Energy Physics, Physical Sciences, physics.ins-det, Mathematical Sciences, Mathematical sciences, Physical sciences
Abstract: NEXT is an experiment dedicated to neutrinoless double beta decay searches in xenon. The detector is a TPC, holding 100 kg of high-pressure xenon enriched in the 136Xe isotope. It is under construction in the Laboratorio Subterráneo de Canfranc in Spain, and it will begin operations in 2015. The NEXT detector concept provides an energy resolutionbetter than 1% FWHM and a topological signal that can be used to reduce the background. Furthermore, the NEXT technology can be extrapolated to a 1 ton-scale experiment. © 2014 J. J. Gómez Cadenas et al.
Published: 2014

30. Present status and future perspectives of the NEXT experiment

Author: Gómez Cadenas, JJ, Álvarez, V, Borges, FIG, Cárcel, S, Castel, J, Cebrián, S, Cervera, A, Conde, CAN, Dafni, T, Dias, THVT, Díaz, J, Egorov, M, Esteve, R, Evtoukhovitch, P, Fernandes, LMP, Ferrario, P, Ferreira, AL, Freitas, EDC, Gehman, VM, Gil, A, Goldschmidt, A, Gómez, H, González-Díaz, D, Gutiérrez, RM, Hauptman, J, Hernando Morata, JA, Herrera, DC, Iguaz, FJ, Irastorza, IG, Jinete, MA, Labarga, L, Laing, A, Liubarsky, I, Lopes, JAM, Lorca, D, Losada, M, Luzón, G, Marí, A, Martín-Albo, J, Martínez, A, Miller, T, Moiseenko, A, Monrabal, F, Monserrate, M, Monteiro, CMB, Mora, FJ, Moutinho, LM, Muñoz Vidal, J, Natal Da Luz, H, Navarro, G, Nebot-Guinot, M, Nygren, D, Oliveira, CAB, Palma, R, Pérez, J, Pérez-Aparicio, JL, Renner, J, Ripoll, L, Rodríguez, A, Rodríguez, J, Santos, FP, Santos, JMFD, Seguí, L, Serra, L, Shuman, D, Simón, A, Sofka, C, Sorel, M, Toledo, JF, Tomás, A, Torrent, J, Tsamalaidze, Z, Veloso, JFCA, Villar, JA, Webb, R, White, J, and Yahlali, N
Subjects: physics.ins-det, Mathematical Sciences, Physical Sciences
Abstract: NEXT is an experiment dedicated to neutrinoless double beta decay searches in xenon. The detector is a TPC, holding 100 kg of high-pressure xenon enriched in the 136Xe isotope. It is under construction in the Laboratorio Subterráneo de Canfranc in Spain, and it will begin operations in 2015. The NEXT detector concept provides an energy resolutionbetter than 1% FWHM and a topological signal that can be used to reduce the background. Furthermore, the NEXT technology can be extrapolated to a 1 ton-scale experiment. © 2014 J. J. Gómez Cadenas et al.
Published: 2014

31. The STAR Time Projection Chamber: A Unique Tool for Studying High Multiplicity Events at RHIC

Author: Anderson, M., Berkovitz, J., Betts, W., Bossingham, R., Bieser, F., Brown, R., Burkes, M., Sanchez, M. Calderon de la Barca, Cebra, D., Cherney, M., Chrin, J., Edwards, W. R., Ghazikhanian, V., Greiner, D., Gilkes, M., Hardtke, D., Harper, G., Hjort, E., Huang, H., Igo, G., Jacobson, S., Keane, D., Klein, S. R., Koehler, G., Kotchenda, L., Lasiuk, B., Lebedev, A., Lin, J., Lisa, M., Matis, H. S., Nystrand, J., Panitkin, S., Reichold, D., Retiere, F., Sakrejda, I., Schweda, K., Shuman, D., Snellings, R., Stone, N., Stringfellow, B., Thomas, J. H., Trainor, T., Trentalange, S., Wells, R., Whitten, C., Wieman, H., Yamamoto, E., and Zhang, W.
Subjects: Nuclear Experiment, Physics - Instrumentation and Detectors
Abstract: The STAR Time Projection Chamber (TPC) is used to record collisions at the Relativistic Heavy Ion Collider (RHIC). The TPC is the central element in a suite of detectors that surrounds the interaction vertex. The TPC provides complete coverage around the beam-line, and provides complete tracking for charged particles within +- 1.8 units of pseudo-rapidity of the center-of-mass frame. Charged particles with momenta greater than 100 MeV/c are recorded. Multiplicities in excess of 3,000 tracks per event are routinely reconstructed in the software. The TPC measures 4 m in diameter by 4.2 m long, making it the largest TPC in the world., Comment: 28 pages, 11 figures
Published: 2003
Full Text: View/download PDF

32. Status of the top-off upgrade of the ALS

Author: Steier, C, Bailey, B, Baptiste, K, Barry, W, Biocca, A, Byrne, W, Chin, M, Donahue, R, Duarte, R, Fahmie, M, Gath, B, Jacobson, S, Julian, J, Jung, JY, Kwiatkowski, S, Marks, S, Mueller, R, Nishimura, H, Oneill, J, Prestemon, S, Robin, D, Rossi, S, Sannibale, F, Scarvie, T, Schlueter, R, Shuman, D, Stover, G, Timossi, C, Warwick, T, Weber, J, and Williams, E
Abstract: The Advanced Light Source is currently being upgraded for top-off operation. This major facility upgrade will provide an improvement in brightness from soft x-ray undulators of about one order of magnitude and keep the ALS competitive with the newest intermediate energy light sources. Major components of the upgrade include making the booster synchrotron capable of full energy operation, radiation safety studies, improvements to interlocks and collimation systems, diagnostics upgrades as well as emittance improvements in the main storage ring. Most hardware necessary as part of the upgrade has been installed and commissioned. The radiation safety studies are making good progress and have passed a first outside peer review succesfully. ©2007 IEEE.
Published: 2007

33. Status of the Top-Off Upgrade of the ALS**This work was supported by the Director, Office of Science, U. S. Department of Energy under Contract No. DE-AC02–05CH11231

Author: Steier, C, Bailey, B, Baptiste, K, Barry, W, Biocca, A, Byrne, W, Chin, M, Donahue, R, Duarte, R, Fahmie, M, Gath, B, Jacobson, S, Julian, J, Jung, JY, Kwiatkowski, S, Marks, S, Mueller, R, Nishimura, H, ONeill, J, Prestemon, S, Robin, D, Rossi, S, Sannibale, F, Scarvie, T, Schlueter, R, Shuman, D, Stover, G, Timossi, C, Warwick, T, Weber, J, and Williams, E
Subjects: Affordable and Clean Energy
Abstract: The Advanced Light Source is currently being upgraded for top-off operation. This major facility upgrade will provide an improvement in brightness from soft x-ray undulators of about one order of magnitude and keep the ALS competitive with the newest intermediate energy light sources. Major components of the upgrade include making the booster synchrotron capable of full energy operation, radiation safety studies, improvements to interlocks and collimation systems, diagnostics upgrades as well as emittance improvements in the main storage ring. Most hardware necessary as part of the upgrade has been installed and commissioned. The radiation safety studies are making good progress and have passed a first outside peer review succesfully. ©2007 IEEE.
Published: 2007

34. Stray field reduction of ALS eddy current septum magnets

Author: Shuman, D, Barry, W, Prestemon, S, Schlueter, R, Steier, C, and Stover, G
Abstract: Stray field from an eddy current septum magnet adversely affects the circulating beam and can be reduced using several techniques. The stray field time history typically has a fast rise section followed by a long exponential decay section when pulsed with a half sine drive current. Changing the drive current pulse to a full sine has the effect of both reducing peak stray field magnitude by ∼ 3x and producing a quick decay from this peak to a lower field level which then has a similar long decay time constant as that from the half sine drive current pulse. A method for tuning the second half-sine (reverse) current pulse to eliminate the long exponential decay section is given. A method for halving the remaining brief peak is also given. © 2005 IEEE.
Published: 2005

35. A Compact High Gradient Pulsed Magnetic Quadpole

Author: Shuman, D., Faltens, A., Kajiyama, Y., Kireeff-Covo, M., and Seidl, P.
Subjects: Energy conservation, consumption, and utilization
Published: 2005

36. Initial Results on Neutralized Drift Compression Experiments (NDCX-IA) For High Intensity Ion Beam

Author: Roy, P.K., Yu, S.S., Henestroza, S., Eylon, S., Waldron, W.L., Bieniosek, F.M., Leitner, M., Shuman, D., Greenway, W.G., Vanecek, D.L., Coleman, J., Baca, D., Logan, B.G., Welch, D.R., Rose, D.V., Thoma, C., Davidson, R.C., Efthimion, P.C., Kaganovich, I., Gilson, E., Sefkow, A.B., and Sharp, W.M.
Subjects: ion beam plasma beam compression longitudinal compression neutralization
Abstract: Ion beam neutralization and compression experiments are designed to determine the feasibility of using compressed high intensity ion beams for high energy density physics (HEDP) experiments and for inertial fusion power. To quantitatively ascertain the various mechanisms and methods for beam compression, the Neutralized Drift Compression Experiment (NDCX) facility is being constructed at Lawrence Berkeley National Laboratory (LBNL). In the first neutralized drift compression experiment, a 280 KeV, 25 mA, K+ ion beam is longitudinally 50-fold compressed using an induction core to produce a velocity tilt. This compression ratio is measured using various diagnostics.
Published: 2005

37. Stray Field Reduction of Als Eddy Current Septum Magnets**Supported by the U.S. Department of Energy under Contract No. DEAC03 76SF00098;

Author: Shuman, D, Barry, W, Prestemon, S, Schlueter, R, Steier, C, and Stover, G
Subjects: Affordable and Clean Energy
Abstract: Stray field from an eddy current septum magnet adversely affects the circulating beam and can be reduced using several techniques. The stray field time history typically has a fast rise section followed by a long exponential decay section when pulsed with a half sine drive current. Changing the drive current pulse to a full sine has the effect of both reducing peak stray field magnitude by ∼ 3x and producing a quick decay from this peak to a lower field level which then has a similar long decay time constant as that from the half sine drive current pulse. A method for tuning the second half-sine (reverse) current pulse to eliminate the long exponential decay section is given. A method for halving the remaining brief peak is also given. © 2005 IEEE.
Published: 2005

38. Initial results on neutralized drift compression experiments (NDCX) for high intensity ion beam

Author: Roy, P.K., Yu, S.S., Henestroza, E., Eylon, S., Waldron, W.L., Bieniosek, F.M., Anders, A., Leitner, M., Shuman, D., Greenway, W.G., Vanecek, D.L., Logan, B.G., Welch, D.R., Rose, D.V., Thoma, C., Davidson, R.C., Efthimion, P.C., Kaganovich, I., Gilson, E.P., Sefkow, A.B., and Sharp, W.M.
Published: 2004

39. Non-intercepting diagostics for the HIF neutralized transport experiment

Author: Roy, P.K., Eylon, S., Hannik, R., Henestroza, E., Ludvig, J., Shuman, D., and Yu, S.S.
Subjects: Energy conservation, consumption, and utilization
Published: 2003

40. Magnetic lattice for the HIF neutralized transport experiment (NTX)

Author: Shuman, D., Eylon, S., Henestroza, E., Roy, P.K., Waldron, W., Yu, S.S., and Houck, T.
Published: 2003

41. Progress in heavy ion driven inertial fusion energy: From scaled experiments to the integrated research experiment

Author: Barnard, J.J., Ahle, L.E., Baca, D., Bangerter, R.O., Bieniosek, F.M., Celata, C.M., Chacon-Golcher, E., Davidson, R.C., Faltens, A., Friedman, A., Franks, R.M., Grote, D.P., Haber, I., Henestroza, E., deHoon, M.J.L., Kaganovich, I., Karpenko, V.P., Kishek, R.A., Kwan, J.W., Lee, E.P., Logan, B.G., Lund, S.M., Meier, W.R., Molvik, A.W., Olson, C., Prost, L.R., Qin, H., Rose, D., Sabbi, G-L., Sangster, T.C., Seidl, P.A., Sharp, W.M., Shuman, D., Vay, J.L., Waldron, W.L., Welch, D., and Yu, S.S.
Subjects: Energy conservation, consumption, and utilization
Published: 2001

42. An Automated System for Collection and Counting of Parasitized Leafminer (Diptera: Agromyzidae) Larvae

Author: Petitt, F. L., Shuman, D. S., Wietlisbach, D. O., and Coffelt, J. A.
Published: 1996
Full Text: View/download PDF

43. Results of the material screening program of the NEXT experiment

Author: Dafni, T., Álvarez, V., Bandac, I., Bettini, A., Borges, F.I.G.M., Camargo, M., Cárcel, S., Cebrián, S., Cervera, A., Conde, C.A.N., Díaz, J., Esteve, R., Fernandes, L.M.P., Fernández, M., Ferrario, P., Ferreira, A.L., Freitas, E.D.C., Gehman, V.M., Goldschmidt, A., Gómez, H., Gómez-Cadenas, J.J., González-Díaz, D., Gutiérrez, R.M., Hauptman, J., Hernando Morata, J.A., Herrera, D.C., Iguaz, F.J., Irastorza, I.G., Labarga, L., Laing, A., Liubarsky, I., Lorca, D., Losada, M., Luzón, G., Marí, A., Martín-Albo, J., Martínez, A., Martínez-Lema, G., Miller, T., Monrabal, F., Monserrate, M., Monteiro, C.M.B., Mora, F.J., Moutinho, L.M., Muñoz Vidal, J., Nebot-Guinot, M., Nygren, D., Oliveira, C.A.B., Pérez, J., Pérez Aparicio, J.L., Renner, J., Ripoll, L., Rodríguez, A., Rodríguez, J., Santos, F.P., dos Santos, J.M.F., Segui, L., Serra, L., Shuman, D., Simón, A., Sofka, C., Sorel, M., Toledo, J.F., Torrent, J., Tsamalaidze, Z., Veloso, J.F.C.A., Villar, J.A., Webb, R.C., White, J.T., and Yahlali, N.
Published: 2016
Full Text: View/download PDF

44. Experiments at The Virtual National Laboratory for Heavy Ion Fusion

Author: Seidl, P.A., Bieniosek, F.M., Celata, C.M., Faltens, A., Kwan, J.W., MacLaren, S.A., Ponce, D., Shuman, D., Yu, S., Ahle, L., Lund, S., Molvik, A., and Sangster, T.C.
Subjects: Energy conservation, consumption, and utilization
Abstract: An overview of experiments is presented, in which the physical dimensions, emittance and perveance are scaled to explore driver-relevant beam dynamics. Among these are beam merging, focusing to a small spot, and bending and recirculating beams. The Virtual National Laboratory for Heavy Ion Fusion (VNL) is also developing two driver-scale beam experiments involving heavy-ion beams with I(sub beam) ~; 1 Ampere to provide guidance for the design of an Integrated Research Experiment (IRE) for driver system studies within the next 5 years. Multiple-beam sources and injectors are being designed and a one-beam module will be built and tested. Another experimental effort will be the transport of such a beam through ~;100 magnetic quadrupoles. The experiment will determine transport limits at high aperture fill factors, beam halo formation, and the influence on beam properties of secondary electron Research into driver technology will be briefly presented, including the development of ferromagnetic core materials, induction core pulsers, multiple-beam quadrupole arrays and plasma channel formation experiments for pinched transport in reactor chambers.
Published: 2000

45. A superconducting quadrupole array for transport of multiple high current beams

Author: Faltens, A. and Shuman, D.
Subjects: Energy conservation, consumption, and utilization
Published: 1999

46. Questioni legali di previsione, protezione e competenza

Author: Shuman, D. W., Darwin-Looney, B., Simon, Robert I., and Tardiff, Kenneth
Published: 2014
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47. STAR Project Conceptual Design Report Update

Author: Berkowitz, J., Bieser, F., Bloomer, M.A., Cebra, D., Chase, S.I., Christie, W., Edwards, W.R., Green, M., Greiner, D., Harris, J.W., Huang, H., Jacobs, P., Jones, P., Kleinfelder, S., LaPierre, R., Lindstrom, P., Margetis, S., Marx, J., Matis, H.S., McParland, C., Mitchell, J., Morse, R., Naudet, C.J., Noggle, T.L., Odyniec, G.J., Olson, D., Poskanzer, A.M., Rai, G., Rasson, J., Ritter, Hans G., Sakrejda, I., Schambach, J., Schroeder, L.S., Shuman, D., Stone, R., Symons, T.J.M., Teitelbaum, L.P., Wieman, H.H., Wilson, W.K.R., Wilson, W.K., Crawford, H.J., Engelage, J.M., and Greiner, L.
Published: 1993

48. Conceptual Design Report for the Solenoidal Tracker at RHIC (STAR)

Author: Berkowitz, J., Bieser, F., Bloomer, M.A., Cebra, D., Chase, S.I., Christie, W., Edwards, W.R., Green, M., Greiner, D., Harris, J.W., Huang, H., Jacobs, P., Jones, P., Kleinfelder, S., LaPierre, R., Lindstrom, P., Margetis, S., Marx, J., Matis, H.S., McParland, C., Mitchell, J., Morse, R., Naudet, C.J., Noggle, T.L., Odyniec, G.J., Olson, D., Poskanzer, A.M., Rai, G., Rasson, J., Ritter, Hans G., Sakrejda, I., Schambach, J., Schroeder, L.S., Shuman, D., Stone, R., Symons, T.J.M., Teitelbaum, L.P., Wieman, H.H., Wilson, W.K.R., Wilson, W.K., Crawford, H.J., Engelage, J.M., and Greiner, L.
Published: 1992

49. Near-intrinsic energy resolution for 30–662 keV gamma rays in a high pressure xenon electroluminescent TPC

Author: Álvarez, V., Borges, F.I.G.M., Cárcel, S., Castel, J., Cebrián, S., Cervera, A., Conde, C.A.N., Dafni, T., Dias, T.H.V.T., Díaz, J., Egorov, M., Esteve, R., Evtoukhovitch, P., Fernandes, L.M.P., Ferrario, P., Ferreira, A.L., Freitas, E.D.C., Gehman, V.M., Gil, A., Goldschmidt, A., Gómez, H., Gómez-Cadenas, J.J., González-Díaz, D., Gutiérrez, R.M., Hauptman, J., Hernando Morata, J.A., Herrera, D.C., Iguaz, F.J., Irastorza, I.G., Jinete, M.A., Labarga, L., Liubarsky, I., Lopes, J.A.M., Lorca, D., Losada, M., Luzón, G., Marí, A., Martín-Albo, J., Martínez, A., Miller, T., Moiseenko, A., Monrabal, F., Monteiro, C.M.B., Mora, F.J., Moutinho, L.M., Muñoz Vidal, J., Natal da Luz, H., Navarro, G., Nebot-Guinot, M., Nygren, D., Oliveira, C.A.B., Palma, R., Pérez, J., Pérez Aparicio, J.L., Renner, J., Ripoll, L., Rodríguez, A., Rodríguez, J., Santos, F.P., dos Santos, J.M.F., Segui, L., Serra, L., Shuman, D., Simón, A., Sofka, C., Sorel, M., Toledo, J.F., Tomás, A., Torrent, J., Tsamalaidze, Z., Vázquez, D., Veloso, J.F.C.A., Villar, J.A., Webb, R.C., White, J.T., and Yahlali, N.
Published: 2013
Full Text: View/download PDF

50. Sampling and trapping to monitor insect populations in relation to CA and/or fumigation

Author: Shuman, D., Epsky, Nancy D., Bridgeman, B., Phillips, T.W, Doud, C. W., Toews, M. D., Subramanyam, B., Flinn, P. W., Reed, C., Hagstrum, D., Flinn, P., and Phillips, T. W.
Published: 2001
Full Text: View/download PDF

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