Silicon Photomultipliers in Particle and Nuclear Physics

Following first large-scale applications in highly granular calorimeters and in neutrino detectors, Silicon Photomultipliers have seen a wide adoption in accelerator-based particle and nuclear physics experiments. Today, they are used for a wide range of different particle detector types, ranging from calorimeters and trackers to particle identification and veto detectors, large volume detectors for neutrino physics and timing systems. This article reviews the current state and expected evolution of these applications, highlighting strengths and limitation of SiPMs and the corresponding design choices in the respective contexts. General trends and adopted technical solutions in the applications are discussed.Comment: 17 pages, 18 figures, review paper published in Nuclear Instruments and Methods A; v2 correcting a missing figure link in tex

Design of optical fiber sensors and interrogation schemes

[ES] Las fibras ópticas son dispositivos muy utilizados en el campo de las telecomunicaciones desde su descubrimiento. En las últimas décadas, las fibras ópticas comenzaron a utilizarse como sensores fotónicos. Los primeros trabajos se centraron en la medición de unas dimensiones físicas en un punto específico. Posteriormente, surgió la posibilidad de medir las propiedades de la fibra óptica en diferentes puntos a lo largo de la fibra. Este tipo de sensores se definen como sensores distribuidos. Los componentes optoelectrónicos fueron desarrollados e investigados para telecomunicaciones. Los avances en las telecomunicaciones hicieron posible el desarrollo de sistemas de interrogación para sensores de fibra óptica, creciendo en paralelo con los avances de las telecomunicaciones. Se desarrollaron sistemas de interrogación de fibra óptica que permiten el uso de una única fibra óptica monomodo estándar como sensor que puede monitorear decenas de miles de puntos de detección al mismo tiempo. Los métodos que extraen la información de detección de la señal reflejada en la fibra óptica son los más empleados debido a la facilidad de acceso al sensor y la flexibilidad de estos sistemas. Los más estudiados son la reflectometría en dominios de tiempo y frecuencia. La reflectometría óptica en el dominio del tiempo (OTDR) fue la primera técnica utilizada para detectar la posición de los fallos en las redes de comunica-ción de fibra óptica. El OTDR sensible a la fase hizo posible detectar la elongación y la temperatura en una posición específica. Paralelamente, los gratings de Bragg (FBG) se convirtieron en los dispositivos más utilizados para implementar sensores en fibra óptica discretos. Se desarrollaron técnicas de multiplexación para realizar la detección en múltiples puntos utilizando FGBs. La reflectometría realizada interrogando arrays de FBG débiles demuestra que mejora el rendimiento del sistema en comparación al uso de una fibra monomodo. Los sistemas de interrogatorio actuales tienen algunos inconvenientes. Algunos de ellos son velocidad de interrogatorio limitada, grandes dimensiones y alto costo. En esta tesis doctoral se desarrollaron nuevos sistemas de interrogación y sensores de fibra óptica para superar algunos de estos inconvenientes. Los sensores de fibra óptica de plástico demuestran ser una plataforma innovadora para desarrollar nuevos sensores y sistemas de interrogación de bajo costo y fáciles de implementar para fibras de plástico comerciales. Se investigó la reflectometría en el dominio del tiempo y las técnicas fotónicas de microondas para la interrogación de una matriz de rejillas débiles que permitieron simplificar el sistema de interrogación para la detección de temperatura y vibración.[CA] Les fibres òptiques són dispositius molt utilitzats en el camp de les telecomunica-cions des del seu descobriment. En les últimes dècades, les fibres òptiques van començar a utilitzar-se com a sensors fotònics. Els primers treballs es van centrar en el mesurament d'unes dimensions físiques en un punt específic. Posteriorment, va sorgir la possibilitat de mesurar les propietats de la fibra òptica en diferents punts al llarg de la fibra. Aquest tipus de sensors es defineixen com a sensors distribüits. Els components optoelectrònics van ser desenvolupats i investigats per a telecomunicacions. Els avanços en les telecomunicacions van fer possi-ble el desenvolupament de sistemes d'interrogació per a sensors de fibra òptica, creixent en paral·lel amb els avanços de les telecomunicacions. Es van desenvolupar sistemes d'interrogació de fibra òptica que permeten l'ús d'una única fibra òptica monomodo estàndard com a sensor que pot monitorar desenes de milers de punts de detecció al mateix temps. Els mètodes que extreuen la informació de detecció del senyal reflectit en la fibra òptica són els més utilitzats a causa de la facilitat d'accés al sensor i la flexibilitat d'aquests sistemes. Els més estudiats són la reflectometría en dominis de temps i freqüència. La reflectometría òptica en el domini del temps (OTDR) va ser la primera tècnica utilitzada per a detectar la posició de les fallades en les xarxes de comunicació de fibra òptica. El OTDR sensible a la fase va fer possible detectar l'elongació i la temperatura en una posició específica. Paral·lelament, els gratings de Bragg (FBG) es van convertir en els dispositius més utilitzats per a implementar sensors en fibra òptica discrets. Es van desenvolupar tècniques de multiplexació per a realitzar la detecció en múltiples punts utilitzant FGBs. La reflectometría realitzada interrogant arrays de FBG febles demostra que millora el rendiment del sistema en comparació a l'ús d'una fibra monomodo. Els sistemes d'interrogatori actuals tenen alguns inconvenients. Alguns d'ells són velocitat d'interrogatori limitada, voluminositat i alt cost. En aquesta tesi doctoral es van desenvolupar nous sistemes d'interrogació i sensors de fibra òptica per a superar alguns d'aquests inconvenients. Els sensors de fibra òptica de plàstic demostren ser una plataforma innovadora per a desenvolupar nous sensors i siste-mes d'interrogació de baix cost i fàcils d'implementar per a fibres de plàstic comercials. Es va investigar la reflectometría en el domini del temps i les tècniques fotòniques de microones per a la interrogació d'una matriu de reixetes febles que van permetre simplificar el sistema d'interrogació per a la detecció de temperatura i vibració.[EN] Optical fibers are devices largely used in telecommunication field since their discovery. In the last decades, optical fibers started to be used as photonic sensors. The first works were focused on the measurement of physical dimensions to a specific point. Afterward, emerged the possibility to measure the optical fiber properties at different locations along the fiber. These kinds of sensors are defined as distributed sensors. The optoelectronic components were developed and investigated for telecommunications. The progress in telecommunication made possible the development of optical fiber sensors interrogation systems, growing in parallel with the advances of telecommunications. Optical fiber interrogation systems were developed to use a single standard monomode optical fiber as a sensor that can monitor tens of thousands of sensing points at the same time. The methods that extract the sensing information from the backscattered signal in the optical fiber are widely employed because of the easiness of access to the sensor element and the flexibility of these systems. The most studied are the reflectometry in time and frequency domains. The optical time domain reflectometry (OTDR) was the first technique used to detect the position of the failures in the optical fiber communication networks. Using phase sensitive OTDR it is possible to sense strain and temperature at a specific position. In parallel, fiber Bragg gratings (FBGs) became the most widely used devices to implement discrete optical fiber sensors. Multiplexing techniques were developed to perform multi points sensing using these gratings. The reflectometry performed interrogating weak FBGs arrays demonstrate to improve the performance of the system employing a single mode fiber. The interrogation systems nowadays have some drawbacks. Some of them are limited speed of interrogation, bulkiness, and high cost. New interrogation systems and optical fiber sensors were developed in this doctoral thesis to overcome some of these drawbacks. Plastic optical fiber sensors demonstrate to be an innovative platform to develop both new sensors and low cost, easy to implement interrogation systems for commercial plastic fibers. Reflectometry in time domain and microwave photonic techniques were investigated for the interrogation of weak gratings array allowed to simplify the interrogation system for the sensing of temperature and vibration.I would like to greatly thank the European Union’s Horizon 2020 Research and Innovation Program that funded the research described in this thesis under the Marie Sklodowska-Curie Action Grant Agreement 722509.Sartiano, D. (2021). Design of optical fiber sensors and interrogation schemes [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/161357TESI

Review: optical fiber sensors for civil engineering applications

Optical fiber sensor (OFS) technologies have developed rapidly over the last few decades, and various types of OFS have found practical applications in the field of civil engineering. In this paper, which is resulting from the work of the RILEM technical committee “Optical fiber sensors for civil engineering applications”, different kinds of sensing techniques, including change of light intensity, interferometry, fiber Bragg grating, adsorption measurement and distributed sensing, are briefly reviewed to introduce the basic sensing principles. Then, the applications of OFS in highway structures, building structures, geotechnical structures, pipelines as well as cables monitoring are described, with focus on sensor design, installation technique and sensor performance. It is believed that the State-of-the-Art review is helpful to engineers considering the use of OFS in their projects, and can facilitate the wider application of OFS technologies in construction industry

Fiber Optic Sensors in Chemical and Biological Applications

The Special Issue "Fiber Optic Sensors in Chemical and Biological Applications” gathers recent original papers. The subjects of the papers cover a broad range of optical fiber chemical sensors and biosensors applied for regulation in bioreactors, to novel concepts of intrinsic optical fiber sensors

Index to NASA Tech Briefs, January - June 1966

Index to NASA technological innovations for January-June 196

The T2K ND280 Off-Axis Pi-Zero Detector

The Pi-Zero detector (P{\O}D) is one of the subdetectors that makes up the off-axis near detector for the Tokai-to-Kamioka (T2K) long baseline neutrino experiment. The primary goal for the P{\O}D is to measure the relevant cross sections for neutrino interactions that generate pi-zero's, especially the cross section for neutral current pi-zero interactions, which are one of the dominant sources of background to the electron neutrino appearance signal in T2K. The P{\O}D is composed of layers of plastic scintillator alternating with water bags and brass sheets or lead sheets and is one of the first detectors to use Multi-Pixel Photon Counters (MPPCs) on a large scale.Comment: 17 pages, submitted to NIM

Desenvolvimento de sensores óticos de pH para aplicação em aquacultura e integração em plataforma híbrida multi-parâmetro

Optical fiber sensors have shown a lot of potential for application in marine environments e regarding monitoring multiple parameters crucial to the growth and well-being of fish, of which pH is one of the most important. Regarding this work, two types of optical fiber sensors were produced: tapers made from a silica single mode fiber with a fiber Bragg grating, and D-shape plastic optical fibers. There were used two different types of D-shape plastic optical fibers: home-made, using a polishing machine, and reused, from old cortisol sensors. Polyaniline (PANI) was synthesized by oxidative polymerization of aniline that was carried out onto the fibers and the selected synthesis time, for which better results were obtained, was 20 minutes. The sensitivity and the sensors’ behavior are determined by the geometry modifications applied onto the fibers, which allow the access of the evanescent wave to the surrounding medium which, in combination with polyaniline, results in a transmission decrease of the spectra as pH increases. The sensors present a certain degree of reproducibility and repeatability with the tapers, the D-shapes home-made and reused having a sensitivity of –0.25 dB/pH, –500 counts/pH and –2500 counts/pH, respectively. However, this is only valid for the increasing order. Regarding the stabilization time, for extreme pH values, whether very acidic, totally protonated, or very basic, totally unprotonated, the stabilization time is shorter. On the other hand, for the transition values of pH, this time is longer, since the PANI is in a transition phase. There were also made cross-sensitivity tests related to ionic strength and temperature, where the sensors did not show a spectra variation in the range of interest. Additionally, the pH sensor was integrated in a hybrid platform with a sensor of nitrites and the optical response to the increment of nitrites in a PBS solution was observed, having only slight variations. The tapers are very useful due to their remote sensing and multiplexing, which is the reason they were spliced with a sensor of nitrites. However, these lack mechanical robustness and ease of fabrication. On the other hand, the opposite happens in the D-shapes. These are more robust and easier to manufacture, but the possibility of multiplexing or remote sensing is challenging or unknown. As a future work, it is intended that the pH sensors produced are applied directly on the aquaculture tanks in order to identify possible water interferences in the measurements and perform tests to optimize the hybrid structure.Os sensores em fibra ótica têm-se mostrado muito promissores para a aplicação em ambientes marinhos na monitorização de vários parâmetros cruciais ao bom crescimento e reprodução dos peixes, dos quais o pH é dos mais importantes no setor da aquacultura. No caso deste trabalho, dois tipos de sensores em fibra ótica foram produzidos: tapers feitos a partir de uma fibra de sílica monomodo com uma rede de Bragg e fibras óticas de plástico com uma D-shape. Em relação às fibras óticas de plástico D-shape, foram usados dois tipo diferentes: umas produzidas no laboratório, usando uma máquina de polir, e outras foram reutilizadas a partir de sensores antigos de cortisol. A polianilina (PANI) foi sintetizada por polimerização oxidativa da anilina na presença das fibras e o tempo de síntese escolhido, para o qual se obteve melhores resultados, foi 20 minutos. A sensibilidade e comportamento do sensor são determinados pelas modificações de geometria aplicadas nas fibras que permitem que a onda evanescente tenha acesso ao meio circundante e, em combinação com a polianilina, isto resulta numa diminuição da transmissão dos espetros à medida que o pH aumenta. Os sensores apresentam um certo grau de reprodutibilidade e repetibilidade, com os tapers, as fibras D-shape produzidas no laboratório e as reutilizadas com sensibilidade de –0.25 dB/pH, –500 contagens/pH e –2500 contagens/pH, respetivamente. Contudo, isto apenas é válido no sentido ascendente de pH. Relativamente ao tempo de estabilização, para os extremos das regiões de pH, quer seja muito ácido, totalmente protonado, ou muito básico, totalmente desprotonado, o tempo de estabilização é mais curto. Já para os valores de transição de pH este tempo é mais elevado, pois a PANI também está numa fase de transição. Foram ainda efetuados testes de sensibilidade cruzada no que diz respeito à força iónica e à temperatura, sendo que os sensores não mostraram uma alteração espetral na zona de interesse. Adicionalmente, integrou-se o sensor de pH numa plataforma híbrida com um sensor de nitritos e observou-se a resposta ótica ao adicionar nitritos a uma solução de PBS, o que resultou em variações pouco significativas. As fibras tapers são bastante úteis devido às suas capacidades de monitorização remota e multiplexagem, daí terem sido fundidos com um sensor de nitritos. No entanto, estes carecem de robustez mecânica e facilidade de fabrico. Por outro lado, nas fibras D-shape o oposto é observado. Estas são mais robustas mecanicamente e fáceis de fabricar, mas a possibilidade de multiplexar ou monitorizar remotamente é desconhecida ou mais complicada. Como trabalho futuro pretende-se que os sensores de pH produzidos sejam aplicados diretamente nos tanques de aquacultura a fim de identificar possíveis interferentes da água nas medidas e de realizar testes para otimizar a estrutura híbrida.Mestrado em Engenharia Físic

Proposal for SPS beam time for the baby MIND and TASD neutrino detector prototypes

The design, construction and testing of neutrino detector prototypes at CERN are ongoing activities. This document reports on the design of solid state baby MIND and TASD detector prototypes and outlines requirements for a test beam at CERN to test these, tentatively planned on the H8 beamline in the North Area, which is equipped with a large aperture magnet. The current proposal is submitted to be considered in light of the recently approved projects related to neutrino activities with the SPS in the North Area in the medium term 2015-2020

Advanced high temperature static strain sensor development

An examination was made into various techniques to be used to measure static strain in gas turbine liners at temperatures up to 1150 K (1600 F). The methods evaluated included thin film and wire resistive devices, optical fibers, surface acoustic waves, the laser speckle technique with a heterodyne readout, optical surface image and reflective approaches and capacitive devices. A preliminary experimental program to develop a thin film capacitive device was dropped because calculations showed that it would be too sensitive to thermal gradients. In a final evaluation program, the laser speckle technique appeared to work well up to 1150 K when it was used through a relatively stagnant air path. The surface guided acoustic wave approach appeared to be interesting but to require too much development effort for the funds available. Efforts to develop a FeCrAl resistive strain gage system were only partially successful and this part of the effort was finally reduced to a characterization study of the properties of the 25 micron diameter FeCrAl (Kanthal A-1) wire. It was concluded that this particular alloy was not suitable for use as the resistive element in a strain gage above about 1000 K