Design, characterization and installation of the NEXT-100 cathode and electroluminescence regions

NEXT-100 is currently being constructed at the Laboratorio Subterr\'aneo de Canfranc in the Spanish Pyrenees and will search for neutrinoless double beta decay using a high-pressure gaseous time projection chamber (TPC) with 100 kg of xenon. Charge amplification is carried out via electroluminescence (EL) which is the process of accelerating electrons in a high electric field region causing secondary scintillation of the medium proportional to the initial charge. The NEXT-100 EL and cathode regions are made from tensioned hexagonal meshes of 1 m diameter. This paper describes the design, characterization, and installation of these parts for NEXT-100. Simulations of the electric field are performed to model the drift and amplification of ionization electrons produced in the detector under various EL region alignments and rotations. Measurements of the electrostatic breakdown voltage in air characterize performance under high voltage conditions and identify breakdown points. The electrostatic deflection of the mesh is quantified and fit to a first-principles mechanical model. Measurements were performed with both a standalone test EL region and with the NEXT-100 EL region before its installation in the detector. Finally, we describe the parts as installed in NEXT-100, following their deployment in Summer 2023.Comment: 35 pages, 25 Figures, update includes accepted version in JINS

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 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

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

Performance of a modular ton-scale pixel-readout liquid argon time projection chamber

The Module-0 Demonstrator is a single-phase 600 kg liquid argon time projection chamber operated as a prototype for the DUNE liquid argon near detector. Based on the ArgonCube design concept, Module-0 features a novel 80k-channel pixelated charge readout and advanced high-coverage photon detection system. In this paper, we present an analysis of an eight-day data set consisting of 25 million cosmic ray events collected in the spring of 2021. We use this sample to demonstrate the imaging performance of the charge and light readout systems as well as the signal correlations between the two. We also report argon purity and detector uniformity measurements and provide comparisons to detector simulations

Revista Brasileira de Zoologia

P. 77-83.Uma sinopse da taxonomia dos Chryxinae com chaves para os gêneros e espécies da subfamília são apresentados. Chryxus bahianus sp. nov. e o macho de Wygodzinskyella travassosi (Lent & Wygodzinsky, 1944) são descritos.Curitib

Neotropical Entomology

Relata-se pela primeira vez a ocorrência de Neosilba zadolicha McAlpine & Steyskal em frutos de umbu-cajazeira (Spondias sp.) no município de Cruz das Almas, BA. O total de 51 exemplares foi obtido de 4100 frutos entre março e julho de 2002. Este é o primeiro registro de N. zadolicha em uma espécie de Anacardiaceae.Londrin

Description of Brontostoma doughertyae n. sp. and a comparative morphological study with B. rubrum (Amyot & Serville, 1843) (Hemiptera: Heteroptera: Reduviidae: Ectrichodiinae)

Submitted by Sandra Infurna ([email protected]) on 2019-02-26T12:12:19Z No. of bitstreams: 1 helciogilsanta_josejuberg_etal_IOC_2005.pdf: 379495 bytes, checksum: af73c2e1b276cdedb42899c0404af33d (MD5)Approved for entry into archive by Sandra Infurna ([email protected]) on 2019-02-26T12:20:23Z (GMT) No. of bitstreams: 1 helciogilsanta_josejuberg_etal_IOC_2005.pdf: 379495 bytes, checksum: af73c2e1b276cdedb42899c0404af33d (MD5)Made available in DSpace on 2019-02-26T12:20:23Z (GMT). No. of bitstreams: 1 helciogilsanta_josejuberg_etal_IOC_2005.pdf: 379495 bytes, checksum: af73c2e1b276cdedb42899c0404af33d (MD5) Previous issue date: 2005Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório Nacional e Internacional de Referência em Taxonomia de Triatomíneos. Rio de Janeiro, RJ. Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Departamento de Entomologia. Laboratório Transmissores de Leishmaniose. Rio de Janeiro, RJ. Brasil.Universidade Federal da Bahia. Escola de Agronomia. Departamento de Fitotecnia. Cruz das Almas, BA, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório Nacional e Internacional de Referência em Taxonomia de Triatomíneos. Rio de Janeiro, RJ. Brasil.Brontostoma doughertyae sp. nov. (Hemiptera-Heteroptera: Reduviidae: Ectrichodiinae), proveniente dos Estados do Espírito Santo e Bahia, Brasil, é descrita com base em exemplares machos. Apresenta-se uma análise comparativa entre as estruturas fálicas de Brontostoma rubrum (Amyot & Serville, 1843) e B. doughertyae sp. nov.. Observou-se que três estruturas se destacam como diagnósticos: o processo do gonoporo (PrG); o suporte do falosoma (SPh) e o falosoma (Ph). Uma chave para as espécies brasileiras de Brontostoma é apresentada.Description of Brontostoma doughertyae n. sp. and a comparative morphological study with B. rubrum (Amyot & Serville, 1843) (Hemiptera: Heteroptera: Reduviidae: Ectrichodiinae) - Brontostoma doughertyae n. sp. (Hemiptera-Heteroptera: Reduviidae: Ectrichodiinae), from Espírito Santo and Bahia States, Brazil is described based on male specimens. A comparative analysis between the phallic structures of Brontostoma rubrum (Amyot & Serville, 1843) and B. doughertyae sp. nov. is presented. Three structures are important to distinguish them: the gonoporal process (PrG); support of the phallosoma (SPh) and the phallosoma (Ph). A key for the brazilian species of Brontostoma is presented

Diversidade de vespas sociais (Hymenoptera: Vespidae) em áreas de cerrado na Bahia

A diversidade de espécies de vespas sociais associadas à vegetação de cerrado no Oeste da Bahia foi analisada neste estudo. Dentre as dezenove espécies de vespas sociais encontradas, Chartergus globiventris de Saussure, Chartergellus communis Richards e Metapolybia cingulata (Fabricius) são registradas pela primeira vez para o estado. O cerrado arbóreo, apesar de apresentar maior riqueza (S = 19) e maior diversidade de espécies (H' = 2,33), apresentou níveis de abundância (N = 87 ninhos) inferiores aos sistemas agrícolas (N = 107 ninhos; S = 8 espécies; H' = 1,84). A fisionomia de cerrado campo sujo apresentou a menor abundância de colônias de vespas sociais (N = 61) e valores intermediários de riqueza (S = 13) e diversidade (H' = 2,20).This study aimed to analyze the social wasps species diversity in a cerrado vegetation at the west region of the State of Bahia. Nineteen species of social wasps were found, with Chartergus globiventris de Saussure, Chartergellus communis Richards and Metapolybia cingulata (Fabricius) being recorded for the first time for the State of Bahia. The arboreous cerrado showed a higher species richness (S = 19) and diversity (H' = 2,33) than the agroecossistems (farms) (S = 8; H' = 1,84). However, nest abundance was higher at the agroecossystems (N = 107 nests) than at the arboreous cerrado (N = 87 nests). The physiognomy of cerrado campo sujo showed the lowest abundance of social wasps colonies (N = 61 nests) and intermediate values of species richness (S = 13) and diversity (H' = 2,20)