Cross section measurement of the muon neutrino charged current single positive pion interaction on hydrocarbon using the T2K near detector with 4∏ solid angle acceptance

T2K és un experiment de neutrinos de base llarga situat a Japó que té com a objectiu medir les oscil·lacions de neutrinos. La línia de llum de neutrins està dissenyada perquè l’espectre d’energia dels neutrins es pugui ajustar, fet que converteix T2K en el primer experiment a utilitzar fora de l’eix. Un accelerador produeix neutrins, que se detecten en un complex de detectors propers i un detector llejano (Super-Kamiokande). Las interaccions de corriente cargada de neutrino muónico en el detector cercano (ND280) s’utilitzen per determinar la tasa d’esdeveniments en el detector lejano i restringir millor els paràmetres de la secció eficaç, que és dominant en l’anàlisi de l’oscil·lació, junt amb la incertesa. en el flux. Presentem l’estudi de les interaccions de corrent carregada al carboni amb un sol pió carregat positivament a l’estat final en el detector proper fora del T2K. Esta senyal, definit com un muó amb càrrega negativa (amb acceptació d’angle sòlid de 4$\pi$), un pió amb càrrega positiva (que es pot observar en el TPC, com una pista aislada en el FGD oa través de l’etiquetatge de electrones de Michel), no mesones i qualsevol nombre de nucleons com a partícules d’estat final. Aquesta senyal constituye l’antecedent principal per a la medició de la desaparició de neutrins muònics quan no es veu el pió carregat, i el seu coneixement preciso és rellevant per a tots els experiments d’oscil·lació de neutrins actuals i planificats. La producció d’un sol pió és sensible principalment als processos ressonants, amb algunes contribucions a la producció de pions no ressonants i coherents. A més, s’han de considerar les interaccions d’estat final en l’objectiu nuclear. La medició de la senyal CC$1\pi^+$ es basa en un resultat anterior, amb canvis significatius en els rangs de partícules cinemàtiques considerades, acceptació d’angles sòlids, un augment en les estadístiques i un nou tractament per a l’avaluació i propagació de incertidumbres sistemàtics. Aquesta tesis ha produït un conjunt de seccions transversals CC$1\pi^+$ de neutrinos muònics de flux integrat en hidrocarburs utilitzant les dades del detector proper fora del T2K. Aquestes mesures de secció transversal s’utilitzen per reduir la sistemàtica relacionada amb el model, que serà especialment important per als experiments d’oscil·lació de la propera generació. Los ángulos de Adler son observables y transportan información sobre la polarización de la resonancia Delta y la interferencia con la producción de un solo pión no resonante. Es van mesurar estadístiques limitades en experiments de càmera de burbuixes, però és possible medir els angles d’Adler per a la producció de pions carregats individuals en interaccions de neutrins amb nuclis pesats blancs.T2K es un experimento de neutrinos de base larga ubicado en Japón que tiene como objetivo medir las oscilaciones de neutrinos. La línea de luz de neutrinos está diseñada para que el espectro de energía de los neutrinos se pueda ajustar, lo que convierte a T2K en el primer experimento en usar fuera del eje. Un acelerador produce neutrinos, que se detectan en un complejo de detectores cercanos y un detector lejano (Super-Kamiokande). Las interacciones de corriente cargada de neutrino muónico en el detector cercano (ND280) se utilizan para predecir la tasa de eventos en el detector lejano y restringir mejor los parámetros de la sección eficaz, que es dominante en el análisis de oscilación, junto con la incertidumbre en el flujo. Presentamos el estudio de las interacciones de corriente cargada en el carbono con un solo pión cargado positivamente en el estado final en el detector cercano fuera del eje T2K. Esta señal, definida como un muón con carga negativa (con aceptación de ángulo sólido de 4$\pi$), un pión con carga positiva (que se puede observar en el TPC, como una pista aislada en el FGD o a través del etiquetado de electrones de Michel), no mesones y cualquier número de nucleones como partículas de estado final. Esta señal constituye el antecedente principal para la medición de la desaparición de neutrinos muónicos cuando no se observa el pión cargado, y su conocimiento preciso es relevante para todos los experimentos de oscilación de neutrinos actuales y planificados. La producción de un solo pión es sensible principalmente a los procesos resonantes, con algunas contribuciones a la producción de piones no resonantes y coherentes. Además, se deben considerar las interacciones de estado final en el objetivo nuclear. La medición de la señal CC$1\pi^+$ se basa en un resultado anterior, con cambios significativos en los rangos de partículas cinemáticas considerados, aceptación de ángulos sólidos, un aumento en las estadísticas y un nuevo tratamiento para la evaluación y propagación de incertidumbres sistemáticas. Esta tesis ha producido un conjunto de secciones transversales CC$1\pi^+$ de neutrinos muónicos de flujo integrado en hidrocarburos utilizando los datos del detector cercano fuera del eje T2K. Estas medidas de sección transversal se utilizan para reducir la sistemática relacionada con el modelo, que será especialmente importante para los experimentos de oscilación de próxima generación. Los ángulos de Adler son observables y transportan información sobre la polarización de la resonancia Delta y la interferencia con la producción de un solo pión no resonante. Se midieron con estadísticas limitadas en experimentos de cámara de burbujas, pero es posible medir los ángulos de Adler para la producción de piones cargados individuales en interacciones de neutrinos con núcleos pesados blanco.T2K is a long-baseline neutrino experiment located in Japan that aims to measure neutrino oscillations. The neutrino beamline is designed so that the neutrino energy spectrum can be tuned making T2K the first experiment to use off-axis. An accelerator produces neutrinos, which are detected in a near detector complex and a far detector (Super-Kamiokande). The muon neutrino charged current interactions in the near detector (ND280) are used to predict the event rate at the far detector and better constrain the cross section parameters, which is dominant in the oscillation analysis, together with the flux uncertainty. We present the study of charged current interactions on carbon with a single positively charged pion in the final state at the T2K off-axis near detector. This signal, defined as a single negatively charged muon and a single positively charged pion exiting from the target nucleus with 4$\pi$ solid angle acceptance, constitutes the main background for the muon neutrino disappearance measurement when the charged pion is not observed, and its precise knowledge is relevant for all current and planned neutrino oscillation experiments. Single pion production is sensitive mainly to resonant processes, with some non-resonant and coherent pion production contributions. Additionally, final-state interactions in the nuclear target have to be considered. The CC$1\pi^+$ signal measurement builds on a previous result, with significant changes to the kinematic particle ranges considered, solid angle acceptance, an increase in statistics, and a new treatment for the evaluation and propagation of systematic uncertainties. This thesis has produced a set of flux integrated muon neutrino CC1pi+ cross sections on hydrocarbon using the T2K off-axis near detector data. These cross section measurements are used to reduce model-related systematics, which will be particularly important for next generation oscillation experiments. Adler Angles are observable carrying information about the polarization of the Delta resonance and the interference with the non-resonant single pion production. They were measured with limited statistics in bubble chamber experiments, but it is possible to measure the Adler angles for single charged pion production in neutrino interactions with heavy nuclei as the target.Universitat Autònoma de Barcelona. Programa de Doctorat en Físic

Neutrino Interaction Vertex Reconstruction in DUNE with Pandora Deep Learning

International audienceThe Pandora Software Development Kit and algorithm libraries perform reconstruction of neutrino interactions in liquid argon time projection chamber detectors. Pandora is the primary event reconstruction software used at the Deep Underground Neutrino Experiment, which will operate four large-scale liquid argon time projection chambers at the far detector site in South Dakota, producing high-resolution images of charged particles emerging from neutrino interactions. While these high-resolution images provide excellent opportunities for physics, the complex topologies require sophisticated pattern recognition capabilities to interpret signals from the detectors as physically meaningful objects that form the inputs to physics analyses. A critical component is the identification of the neutrino interaction vertex. Subsequent reconstruction algorithms use this location to identify the individual primary particles and ensure they each result in a separate reconstructed particle. A new vertex-finding procedure described in this article integrates a U-ResNet neural network performing hit-level classification into the multi-algorithm approach used by Pandora to identify the neutrino interaction vertex. The machine learning solution is seamlessly integrated into a chain of pattern-recognition algorithms. The technique substantially outperforms the previous BDT-based solution, with a more than 20% increase in the efficiency of sub-1 cm vertex reconstruction across all neutrino flavours

Neutrino Interaction Vertex Reconstruction in DUNE with Pandora Deep Learning

International audienceThe Pandora Software Development Kit and algorithm libraries perform reconstruction of neutrino interactions in liquid argon time projection chamber detectors. Pandora is the primary event reconstruction software used at the Deep Underground Neutrino Experiment, which will operate four large-scale liquid argon time projection chambers at the far detector site in South Dakota, producing high-resolution images of charged particles emerging from neutrino interactions. While these high-resolution images provide excellent opportunities for physics, the complex topologies require sophisticated pattern recognition capabilities to interpret signals from the detectors as physically meaningful objects that form the inputs to physics analyses. A critical component is the identification of the neutrino interaction vertex. Subsequent reconstruction algorithms use this location to identify the individual primary particles and ensure they each result in a separate reconstructed particle. A new vertex-finding procedure described in this article integrates a U-ResNet neural network performing hit-level classification into the multi-algorithm approach used by Pandora to identify the neutrino interaction vertex. The machine learning solution is seamlessly integrated into a chain of pattern-recognition algorithms. The technique substantially outperforms the previous BDT-based solution, with a more than 20% increase in the efficiency of sub-1 cm vertex reconstruction across all neutrino flavours

Neutrino Interaction Vertex Reconstruction in DUNE with Pandora Deep Learning

International audienceThe Pandora Software Development Kit and algorithm libraries perform reconstruction of neutrino interactions in liquid argon time projection chamber detectors. Pandora is the primary event reconstruction software used at the Deep Underground Neutrino Experiment, which will operate four large-scale liquid argon time projection chambers at the far detector site in South Dakota, producing high-resolution images of charged particles emerging from neutrino interactions. While these high-resolution images provide excellent opportunities for physics, the complex topologies require sophisticated pattern recognition capabilities to interpret signals from the detectors as physically meaningful objects that form the inputs to physics analyses. A critical component is the identification of the neutrino interaction vertex. Subsequent reconstruction algorithms use this location to identify the individual primary particles and ensure they each result in a separate reconstructed particle. A new vertex-finding procedure described in this article integrates a U-ResNet neural network performing hit-level classification into the multi-algorithm approach used by Pandora to identify the neutrino interaction vertex. The machine learning solution is seamlessly integrated into a chain of pattern-recognition algorithms. The technique substantially outperforms the previous BDT-based solution, with a more than 20% increase in the efficiency of sub-1 cm vertex reconstruction across all neutrino flavours

The DUNE Far Detector Vertical Drift Technology, Technical Design Report

International audienceDUNE is an international experiment dedicated to addressing some of the questions at the forefront of particle physics and astrophysics, including the mystifying preponderance of matter over antimatter in the early universe. The dual-site experiment will employ an intense neutrino beam focused on a near and a far detector as it aims to determine the neutrino mass hierarchy and to make high-precision measurements of the PMNS matrix parameters, including the CP-violating phase. It will also stand ready to observe supernova neutrino bursts, and seeks to observe nucleon decay as a signature of a grand unified theory underlying the standard model. The DUNE far detector implements liquid argon time-projection chamber (LArTPC) technology, and combines the many tens-of-kiloton fiducial mass necessary for rare event searches with the sub-centimeter spatial resolution required to image those events with high precision. The addition of a photon detection system enhances physics capabilities for all DUNE physics drivers and opens prospects for further physics explorations. Given its size, the far detector will be implemented as a set of modules, with LArTPC designs that differ from one another as newer technologies arise. In the vertical drift LArTPC design, a horizontal cathode bisects the detector, creating two stacked drift volumes in which ionization charges drift towards anodes at either the top or bottom. The anodes are composed of perforated PCB layers with conductive strips, enabling reconstruction in 3D. Light-trap-style photon detection modules are placed both on the cryostat's side walls and on the central cathode where they are optically powered. This Technical Design Report describes in detail the technical implementations of each subsystem of this LArTPC that, together with the other far detector modules and the near detector, will enable DUNE to achieve its physics goals

The DUNE Far Detector Vertical Drift Technology, Technical Design Report

DUNE is an international experiment dedicated to addressing some of the questions at the forefront of particle physics and astrophysics, including the mystifying preponderance of matter over antimatter in the early universe. The dual-site experiment will employ an intense neutrino beam focused on a near and a far detector as it aims to determine the neutrino mass hierarchy and to make high-precision measurements of the PMNS matrix parameters, including the CP-violating phase. It will also stand ready to observe supernova neutrino bursts, and seeks to observe nucleon decay as a signature of a grand unified theory underlying the standard model. The DUNE far detector implements liquid argon time-projection chamber (LArTPC) technology, and combines the many tens-of-kiloton fiducial mass necessary for rare event searches with the sub-centimeter spatial resolution required to image those events with high precision. The addition of a photon detection system enhances physics capabilities for all DUNE physics drivers and opens prospects for further physics explorations. Given its size, the far detector will be implemented as a set of modules, with LArTPC designs that differ from one another as newer technologies arise. In the vertical drift LArTPC design, a horizontal cathode bisects the detector, creating two stacked drift volumes in which ionization charges drift towards anodes at either the top or bottom. The anodes are composed of perforated PCB layers with conductive strips, enabling reconstruction in 3D. Light-trap-style photon detection modules are placed both on the cryostat's side walls and on the central cathode where they are optically powered. This Technical Design Report describes in detail the technical implementations of each subsystem of this LArTPC that, together with the other far detector modules and the near detector, will enable DUNE to achieve its physics goals

Doping liquid argon with xenon in ProtoDUNE Single-Phase: effects on scintillation light

Doping of liquid argon TPCs (LArTPCs) with a small concentration of xenon is a technique for light-shifting and facilitates the detection of the liquid argon scintillation light. In this paper, we present the results of the first doping test ever performed in a kiloton-scale LArTPC. From February to May 2020, we carried out this special run in the single-phase DUNE Far Detector prototype (ProtoDUNE-SP) at CERN, featuring 770 t of total liquid argon mass with 410 t of fiducial mass. The goal of the run was to measure the light and charge response of the detector to the addition of xenon, up to a concentration of 18.8 ppm. The main purpose was to test the possibility for reduction of non-uniformities in light collection, caused by deployment of photon detectors only within the anode planes. Light collection was analysed as a function of the xenon concentration, by using the pre-existing photon detection system (PDS) of ProtoDUNE-SP and an additional smaller set-up installed specifically for this run. In this paper we first summarize our current understanding of the argon-xenon energy transfer process and the impact of the presence of nitrogen in argon with and without xenon dopant. We then describe the key elements of ProtoDUNE-SP and the injection method deployed. Two dedicated photon detectors were able to collect the light produced by xenon and the total light. The ratio of these components was measured to be about 0.65 as 18.8 ppm of xenon were injected. We performed studies of the collection efficiency as a function of the distance between tracks and light detectors, demonstrating enhanced uniformity of response for the anode-mounted PDS. We also show that xenon doping can substantially recover light losses due to contamination of the liquid argon by nitrogen.Doping of liquid argon TPCs (LArTPCs) with a smallconcentration of xenon is a technique for light-shifting andfacilitates the detection of the liquid argon scintillationlight. In this paper, we present the results of the first dopingtest ever performed in a kiloton-scale LArTPC. From February to May2020, we carried out this special run in the single-phase DUNE FarDetector prototype (ProtoDUNE-SP) at CERN, featuring 720 t of totalliquid argon mass with 410 t of fiducial mass. A 5.4 ppm nitrogencontamination was present during the xenon doping campaign. The goalof the run was to measure the light and charge response of thedetector to the addition of xenon, up to a concentration of18.8 ppm. The main purpose was to test the possibility forreduction of non-uniformities in light collection, caused bydeployment of photon detectors only within the anode planes. Lightcollection was analysed as a function of the xenon concentration, byusing the pre-existing photon detection system (PDS) of ProtoDUNE-SPand an additional smaller set-up installed specifically for thisrun. In this paper we first summarize our current understanding ofthe argon-xenon energy transfer process and the impact of thepresence of nitrogen in argon with and without xenon dopant. We thendescribe the key elements of ProtoDUNE-SP and the injection methoddeployed. Two dedicated photon detectors were able to collect thelight produced by xenon and the total light. The ratio of thesecomponents was measured to be about 0.65 as 18.8 ppm of xenon wereinjected. We performed studies of the collection efficiency as afunction of the distance between tracks and light detectors,demonstrating enhanced uniformity of response for the anode-mountedPDS. We also show that xenon doping can substantially recover lightlosses due to contamination of the liquid argon by nitrogen.Doping of liquid argon TPCs (LArTPCs) with a small concentration of xenon is a technique for light-shifting and facilitates the detection of the liquid argon scintillation light. In this paper, we present the results of the first doping test ever performed in a kiloton-scale LArTPC. From February to May 2020, we carried out this special run in the single-phase DUNE Far Detector prototype (ProtoDUNE-SP) at CERN, featuring 720 t of total liquid argon mass with 410 t of fiducial mass. A 5.4 ppm nitrogen contamination was present during the xenon doping campaign. The goal of the run was to measure the light and charge response of the detector to the addition of xenon, up to a concentration of 18.8 ppm. The main purpose was to test the possibility for reduction of non-uniformities in light collection, caused by deployment of photon detectors only within the anode planes. Light collection was analysed as a function of the xenon concentration, by using the pre-existing photon detection system (PDS) of ProtoDUNE-SP and an additional smaller set-up installed specifically for this run. In this paper we first summarize our current understanding of the argon-xenon energy transfer process and the impact of the presence of nitrogen in argon with and without xenon dopant. We then describe the key elements of ProtoDUNE-SP and the injection method deployed. Two dedicated photon detectors were able to collect the light produced by xenon and the total light. The ratio of these components was measured to be about 0.65 as 18.8 ppm of xenon were injected. We performed studies of the collection efficiency as a function of the distance between tracks and light detectors, demonstrating enhanced uniformity of response for the anode-mounted PDS. We also show that xenon doping can substantially recover light losses due to contamination of the liquid argon by nitrogen

DUNE Offline Computing Conceptual Design Report

This document describes Offline Software and Computing for the Deep Underground Neutrino Experiment (DUNE) experiment, in particular, the conceptual design of the offline computing needed to accomplish its physics goals. Our emphasis in this document is the development of the computing infrastructure needed to acquire, catalog, reconstruct, simulate and analyze the data from the DUNE experiment and its prototypes. In this effort, we concentrate on developing the tools and systems thatfacilitate the development and deployment of advanced algorithms. Rather than prescribing particular algorithms, our goal is to provide resources that are flexible and accessible enough to support creative software solutions as HEP computing evolves and to provide computing that achieves the physics goals of the DUNE experiment

Reconstruction of interactions in the ProtoDUNE-SP detector with Pandora

International audienceThe Pandora Software Development Kit and algorithm libraries provide pattern-recognition logic essential to the reconstruction of particle interactions in liquid argon time projection chamber detectors. Pandora is the primary event reconstruction software used at ProtoDUNE-SP, a prototype for the Deep Underground Neutrino Experiment far detector. ProtoDUNE-SP, located at CERN, is exposed to a charged-particle test beam. This paper gives an overview of the Pandora reconstruction algorithms and how they have been tailored for use at ProtoDUNE-SP. In complex events with numerous cosmic-ray and beam background particles, the simulated reconstruction and identification efficiency for triggered test-beam particles is above 80% for the majority of particle type and beam momentum combinations. Specifically, simulated 1 GeV/$c$ charged pions and protons are correctly reconstructed and identified with efficiencies of 86.1$\pm0.6$% and 84.1$\pm0.6$%, respectively. The efficiencies measured for test-beam data are shown to be within 5% of those predicted by the simulation

DUNE Offline Computing Conceptual Design Report

This document describes Offline Software and Computing for the Deep Underground Neutrino Experiment (DUNE) experiment, in particular, the conceptual design of the offline computing needed to accomplish its physics goals. Our emphasis in this document is the development of the computing infrastructure needed to acquire, catalog, reconstruct, simulate and analyze the data from the DUNE experiment and its prototypes. In this effort, we concentrate on developing the tools and systems thatfacilitate the development and deployment of advanced algorithms. Rather than prescribing particular algorithms, our goal is to provide resources that are flexible and accessible enough to support creative software solutions as HEP computing evolves and to provide computing that achieves the physics goals of the DUNE experiment