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We measured the surface resistance of titanium, amorphous carbon, and nonevaporable getter (NEG) coatings on copper samples, representative of surface treatments of beam-facing components in the High-Luminosity Large Hadron Collider at CERN. Measurements were done at room temperature as well as at liquid nitrogen temperature (77 K) by means of a novel large dielectric resonator operating at 3.4 GHz. The impact of a 100 to 400 nm titanium layer or a 50-nm amorphous carbon layer was negligible both at room temperature and down to 77 K in comparison to copper, while a thick (1140 nm) NEG layer showed a measurable increase in the surface resistance, being more significant at low temperature. The dielectric resonator proved to be a useful tool to characterize the surface resistance of flat samples with different surface treatments and sizes up to 10 cm for accelerator applications. Furthermore, its construction and operation are much simpler compared to other test devices currently in use, and it can provide accurate experimental data for the evaluation of the beam coupling impedance., Peer Reviewed, Postprint (published version)

The influence of medium-to-high energy synchrotron radiation (SR) (˜10–100 keV) produced by the ALBA Synchrotron Light Source on state-of-the-art REBCO coated conductors (CCs) has been studied to assess the feasibility of using high-temperature superconductors for the beam screen of future circular colliders. Long-term irradiation studies were conducted with ex-situ surface resistance testing by using a dielectric resonator. In addition, a cryogenic test system was established for in-situ measurements of the critical temperature and surface impedance of REBCO-CCs during synchrotron irradiation, with intensities similar to or above those generated by proton beams circulating in the vacuum chamber in the future circular collider hadron–hadron design. It is shown that the SR impact does not introduce any macroscopic defects that permanently alter the critical temperature or surface impedance of REBCO-CCs. However, the most significant effect of SR is a transient increase in the REBCO's surface impedance. This effect is likely caused by heat, as the material returns to its original impedance values once the radiation exposure stops. The correlation between the time structure of the SR and the possibility of suppressing the Cooper pairing mechanism is also discussed., This work was supported by CERN under Grants FCC-GOV-CC-0072/KE3358, FCC-GOV-CC-0153/KE4106 and FCC-GOV-CC-0208/KE4947/ATS. N Tagdulang acknowledges MSCA-COFUND-2016-754397 for the PhD grant., Peer Reviewed, Postprint (published version)

We describe a method for performing cryogenic permittivity and loss tangent measurements of small (few mm), high-permittivity dielectric cylinders used in surface impedance measurement of superconductors. We combine the use of sapphire and PTFE supports to hold the dielectric under test and provide good thermal conductivity to the cold head. Additionally, the sapphire support is used to facilitate the measurement of the cavity's metal loss and the assessment of its contribution to the overall resonator loss., Authors wish to acknowledge the support provided by CERN under Grants FCC-GOV-CC-0072/KE3358 and FCC-GOV-CC-0210/KE4945. NT acknowledges MSCA-COFUND-2016-754397 for the PhD grant., Peer Reviewed, Postprint (author's final draft)

The Future Circular Collider study creates a conceptual design for a post-LHC particle accelerator using 16T superconducting dipoles to achieve collision energies of up to 100TeV in a 90km circumference ring. A copper-coated beam screen, similar to that used in the LHC, is planned. However, the undertaken research indicates that copper at the high working temperature of 50K has a strong influence on the accelerator's performance, particularly at injection energy. In this work, we relate the experimentally determined properties of REBCO-coated conductors with their potential performance in the FCC-hh beam screen. Specifically, we use a round pipe approximation to demonstrate that a beam screen coated with a combination of REBCO and copper can have a much lower resistive wall impedance than one using only copper. The reduction is substantial (several orders of magnitude), and is observed in both the longitudinal and transverse wall impedance. Such a reduction has important effects on beam stability, operating costs, potential reduction in beam screen size, and lowering the stringent specifications of the 16T magnets required for the Future Circular Hadron Collider., The authors acknowledge the support and samples provided by Bruker HTS GmbH, Fujikura Ltd, SuNAM CO Ltd SuperOx, SuperPower Inc. and Theva Dünnschichttechnik GmbH. UPC funding was also provided through the Unit of Excellence María de Maeztu MDM2016-0600. N. Tagdulang acknowledges MSCA-COFUND-2016-754397 fot hte PhD Grant., Peer Reviewed, Postprint (published version)

Non Evaporable Getter (NEG) coating has been employed extensively in the particle accelerator especial-ly where the vacuum conductance of the vessel is se-verely restricted and ultra-high vacuum condition is required. NEG coating will significantly reduce the outgassing rate and provides active pumping surface for H2, CO and CO2. In addition, it has been proven that NEG coated surfaces have a very low secondary electron yield, as well as low photon and electron stimulated desorption yields. However, the existing NEG film increases the RF surface resistance of the beam pipe. In order to increase NEG coating conductivity, at ASTeC, in the past several years, the alternative NEG composition have been studied by adding more con-ductive element such as Cu, Au, Al and Ag. In this study, we report on the photon stimulated desorption, activation temperature and surface resistance from room temperature to cryogenic temperature for a new NEG quaternary alloy of TiVZrAg as function of the film composition., Peer Reviewed, Postprint (published version)

smart antenna systems and wireless propagation of ultrabroadband signals in the terahertz (THz) band, The terahertz (THz) band (0.1 - 10 THz) will be instrumental to fulfill the future demands for sixth generation (6G) wireless communications due to its tens to hundreds of gigahertz (GHz) of contiguous bandwidth and the expected peak of 1 tera-bit-per-second (Tbps) data rates. However, this unused and unexplored spectrum does not come with its own challenges. One of the biggest challenges in supporting the required high transmission speed will be the limited power of the transmitting devices, which will be key to combat the high propagation losses and the molecular absorption present in this frequency band. This will require the use of highly directional antennas, and the study of novel antennas will become necessary to meet the expectations. In this thesis, we propose the use of leaky-wave antenna arrays for THz communications. The beam-steering capabilities of leaky-wave antennas provide them with an alternative method of radiating high directive beams over a wide range of directions. By using a linear array of leaky-wave antennas, two possibilities are described. On the one hand, it allows to perform three-dimensional beamforming in order to achieve even higher directivities and to scan in both the elevation and azimuth angles. On the other hand, it will be proven that is also possible to do spatial multiplexing thanks to its directive pattern and beam-steering behaviour, increasing the achievable data rates of the link. Numerical and simulation results are presented in order to corroborate this statements.

After the discovery of the Higgs boson, the Conséil Européen pour la Recherche Nucléaire (CERN) started a new research study for the foundation of a new particle accelerator that would extend the energy frontier in the research of particle physics, the Future Circular Collider (FCC). This degree thesis is performed in the framework of a consortium project between CERN, Universitat Polit ècnica de Catalunya (UPC), CELLS/ALBA Synchrotron Light Source, Institut de Ci`encies Materials de Barcelona (ICMAB) and Institut de Física d¿Altes Energies (IFAE) and as the continuation of the work realized in ALBA¿s internship, which tries to characterize the coating materials employed in the beam pipe of the hadron-hadron collider of the FCC accelerator (FCC-hh). The purpose of this thesis is the design, study, fabrication, and test of a parallel plate resonator (PPR) capable of measuring the surface impedance of High-Temperature Superconductor Coated Conductors (HTS-CC) at frequencies around 2 kHz and 4 GHz to evaluate if the HTS-CC of some providers fulfill the electromagnetic conditions required for the beam pipe¿s coating. The design is intended to be employed in a 16T cryostat at temperatures around 20 K and 100K to simulate the requirements of the accelerator. Nevertheless, in this thesis, we will only test a preliminary prototype in a 0T Janis cryostat using copper samples. The fundamental mode TEM1,0 is the only resonance mode that must be operable for surface impedance measurements. However, other resonance modes between 1 GHz and 20 GHz will be analyzed to determine if they are also operable or not. The electromagnetic design of the PPR was designed and studied with an electromagnetic (EM) analysis 3D software called CST Studio Suite, whereas the mechanical prototype was designed with a 3D design software called Autodesk Fusion 360. The prototype was manufactured in the UPC¿s workshop, and the samples of the experimental analysis were processed with an Algorithm for Res, Objectius de Desenvolupament Sostenible::9 - Indústria, Innovació i Infraestructura, Objectius de Desenvolupament Sostenible::9 - Indústria, Innovació i Infraestructura

To assess the feasibility of using high-temperature superconductors for the beam screens of future circular colliders, we have undertaken a study of the power dependence of the microwave surface resistance in state-of-the-art REBCO coated conductors at about 8GHz and 50K. We have employed a dielectric resonator to produce radio-frequency electromagnetic fields on the surface of the coated conductors having amplitudes similar to those generated by proton bunches circulating in the vacuum chamber of the proposed hadron-hadron Future Circular Collider at CERN. We show that surface resistances in REBCO coated conductors without artificial pinning centers are more affected by a radio-frequency magnetic field than those containing nano-inclusions. Despite that, at 8GHz, 50K, and 9T, most REBCO coated conductors studied outperform copper in terms of surface resistance, with the best sample having a 2.3mO surface resistance while being subject to an RF field 2.5 times stronger than that in the FCC-hh. We also extrapolate the measured data to 16T and 1GHz, the actual FCC-hh dipole magnetic field, and mid beam frequency spectrum, demonstrating the possibility of lowering the surface resistance of the vacuum chamber by up to two orders of magnitude compared to copper. Further, we discuss the correlation between the time structure of the electromagnetic fields provided by vector network analyzers compared to the proton bunches' time structure in the collider and present the effect of low alternating magnetic fields on vortex displacement and the possibility of demagnetization of superconducting samples., The authors acknowledge the support and samples provided by Bruker HTS GmbH, Fujikura Ltd, SuNAM CO Ltd SuperOx, SuperPower Inc. and Theva Dünnschichttechnik GmbH. This work was supported by CERN under Grant Nos. FCC-GOV-CC-0072/KE3358, FCC-GOV-CC-0153/KE4106 and FCC-GOV-CC-0208/KE4947/ATS. UPC funding was also provided through the Unit of Excellence María de Maeztu MDM2016-0600. N Tagdulang and A Romanov acknowledge MSCA-COFUND-2016-754397 for the PhD Grant. ICMAB authors acknowledge RTI2018-095853-B-C21 SuMaTe from MICINN and co-financing by the European Regional Development Fund; 2017-SGR 1519 from Generalitat de Catalunya and COST Action NANOCO-HYBRI (CA16218) from EU, the Center of Excellence award Severo Ochoa CEX2019- 000917-S., Peer Reviewed, Postprint (published version)

For the future high energy colliders being under the design at this moment, the choice of a low surface impedance beam screen coating material has become of fundamental importance to ensure sufficiently low beam impedance and consequently guaranteed stable operation at high currents. We have studied the use of high-temperature superconducting coated conductors as possible coating materials for the beam screen of the FCC-hh. In addition, amorphous carbon coating and laser-based surface treatment techniques are effective surface treatments to lower the secondary electron yield and minimise the electron cloud build-up. We have developed and adapted different experimental setups based on resonating structures at frequencies below 10 GHz to study the response of these coatings and their modified surfaces under the influence of RF fields and DC magnetic fields up to 9¿T. Taking the FCC-hh as a reference, we will show that the surface resistance for REBCO-CCs is much lower than that of Cu. Further we show that the additional surface modifications can be optimised to minimise their impact on the surface impedance. Results from selected coatings will be presented., Work supported by CERN under Grants FCC-GOV-CC-0210 (KE4945/ATS), FCC-GOV-CC-0209 (KE4946/ATS) and FCC-GOV-CC0208 (KE4947/ATS). ICMAB funding through RTI2018-095853-B-C21 SuMaTe from MICINN and co-financing by the European Regional Development Fund, 2017-SGR 1519 from Generalitat de Catalunya, and COST Action NANOCO-HYBRI (CA16218) from EU, the Center of Excellence award Severo Ochoa CEX2019-000917-S. UPC funding through the Unit of Excellence Maria de Maetzu MDM2016-0600. N. Tagdulang and A. Romanov acknowledge MSCA-COFUND-2016-754397 for the PhD grant., Peer Reviewed, Postprint (published version)

Electrocardiogram (ECG) synchronization is useful to avoid the effects of cardiac motion in medical measurements, and is widely used in standard medical imaging. A number of medical equipment include embedded commercial synchronizers. However, the use of independent synchronization modules is sometimes needed when several non-integrated instruments are used, or in the development of new medical instruments and procedures. We present a simple low-cost ECG synchronizer module based on an Arduino controller board that converts the ECG signal into a transistor-transistor-logic (TTL) one, allowing real-time medical measurements triggered at specific phases of the cardiac cycle. The device and conversion algorithm developed is optimized in vitro using synthetic and human ECG signals, and tested in vivo on three swine specimens. Error rates during the in vivo testing stage remain below the 2% of the cycles in all animals and critical false positives are less than 1%, which is sufficient for most applications. Possible algorithm updates are discussed if its performance needs to be improved., This research was funded by grants from the Instituto de Salud Carlos III [PI18/00256], the Fundació La MARATÓ de TV3 (20153530/31), the Sociedad Española de Cardiología, and the Generalitat de Catalunya [2017-SGR-483]. This work was also funded by CaixaImpulse (CI20/00230), and the Red de Terapia Celular—TerCel [RD16/0011/0006] and CIBER Cardiovascular [CB16/11/00403] projects, as part of the Plan Nacional de I+D+I, and cofunded by ISCIII-Subdirección General de Evaluación y el Fondo Europeo de Desarrollo Regional (FEDER). F.M. acknowledges support from the Catalan Government through COFUND and the Unidad de Excelencia Maria de Maeztu MDM-2016-0600., Peer Reviewed, Postprint (published version)

In the past few years, it has been established that Laser Ablation Surface Engineering (LASE) is a very effective way of producing surfaces which have Secondary Electron Yields (SEY)¿<¿1. This can be achieved with a variety of laser pulse durations from nano-to picoseconds. However, the features (i.e. moderately deep grooves and nano-particulates) that help to reduce the SEY can produce undesirable effects such as an increase in the RF surface resistance. In this paper we discuss the methods employed utilising the dielectric resonator technique to quantify the surface resistance of laser treated copper and stainless steel samples. The quantification is based on a non-destructive measurement of high-frequency losses on the conducting surface. It has been demonstrated that the LASE surface can be produced with SEY<1 and an RF surface resistance of only ~6% higher than that on untreated surfaces. Furthermore, a comparative study of electron stimulated desorption (ESD) between the LASE treated and untreated samples of copper and stainless steel is reported for H2, CH4, CO and CO2. It has been shown that there are negligible differences in ESD between LASE treated and untreated stainless steel. It has been demonstrated that LASE-treated copper samples have a considerable reduction in ESD as compared with untreated sample., This work was supported in part by CERN under Grant FCC-GOV-CC-0210 (KE4945/ATS) and Grant FCCGOV-CC-0209 (KE4946/ATS) and in part by UPC funding through the Unit of Excellence María de Maeztu under Grant MDM2016-0600. The work of Nikki D. Tagdulang was supported by MSCA-COFUND-2016-754397., Peer Reviewed, Postprint (published version)

We describe an algorithm capable of extracting the unloaded quality factor and the resonant frequency of microwave resonators from vector S-parameters. Both symmetrical (Lorentzian) and asymmetrical (Fano) transmission responses are supported. The algorithm performs an adaptive outlier removal to discard measurement points affected by noise or distortion. It removes the effects caused by imperfections in the device (such as modes with close resonance frequencies or stray coupling between the resonator ports) or the experimental setup (such as lack of isolation or dispersion in the test set and cables). We present an extensive assessment of the algorithm performance based on a numerical perturbation analysis and the evaluation of S-parameter fitting results obtained from network analyzer measurements and resonator equivalent circuits. Our results suggest that uncertainty is mainly caused by factors that distort the frequency dependence of the S-parameters, such as cabling and coupling networks, and is highly dependent on the device measured. Our perturbation analysis shows improved results with respect to those of previous publications. Our source code is written in Python using open-source packages and is publicly available under a freeware license., This work was supported in part by CERN under Grant FCC-GOV-CC-0210 (KE4945/ATS) and Grant FCCGOV-CC-0209 (KE4946/ATS) and in part by UPC funding through the Unit of Excellence María de Maeztu under Grant MDM2016-0600. The work of Nikki D. Tagdulang was supported by MSCA-COFUND-2016-754397., Peer Reviewed, Postprint (author's final draft)

The advent of biodegradable stents as a solution to human arteries obstructions may overcome pathologies related to former non-degradable stents. In this work we aim to characterize these state-of-the-art prosthetic devices using near-field probes to couple with magnesium biodegradable stents. By analysing the transmission coefficient (S21) we intend to monitor the degradation process over time under in vivo-like conditions, as well as to detect structural defects in the stent?s scaffold., The main goal of this work is to use Microwave Spectrometry (MWS) techniques to monitor the degradation/ageing process of biodegradable stents. To do so, we will first measure three metallic biodegradable stents of different lengths and the same diameter sunken in Ringer Lactate Solution (RLS); given that this solution emulates blood's physiological properties, the stents will gradually degrade. During this process, we will analyse how our spectral response changes along time. Secondly, to slow down the degradation process and match the time it would take $in-vivo$, stents will be wrapped in coronary arteries and measured in RLS. Lastly, stents will undergo a series of cuts in order to compare their spectral behaviour when fractured to that of non-degradable stents. Results will show how the stent degradation process can be monitored by means of MWS; additionally, this work will also show how response of both non-biodegradable and biodegradable stents is comparable, thus allowing to monitor not only the degradation process of the latter but their faults too.

Resolved

Aquesta tesi es desenvolupa en el marc d'una associació de projectes del consorci entre ALBA Synchrotron Light Source (ALBA), el Conseil Européen pour la Recherche Nucléaire (CERN), l'Institut de Ciència de Materials de Barcelona (ICMAB), lInstitut de Física d'Altes Energies (IFAE) i Universitat Politècnica de Catalunya (UPC). L'objectiu principal de la col·laboració és obtenir la impedància superficial dels conductors recoberts de superconductors d'alta temperatura (HTS-CCs) a les freqüències de microones que s'utilitzaran com a recobriment alternatiu a la pantalla de feixos del Future Circular Collider hadron-hadron (FCC-hh). L'ALBA i UPC han desenvolupat ressonadors de microones capaços de mesurar les propietats clau del HTS-CC amb diverses mesures de mostres de materials subministrats per diversos fabricants. El principal objectiu d'aquest treball es concentra en el desenvolupament d'un codi de Python per processar dades experimentals buscant paràmeters com factor de qualitat i impedància de superfície mitjançant algoritmes adaptats a la literatura tècnica.

The main objective of this project is to design, fabricate and test a resonator capable of measuring the required properties of different dielectric samples in the microwave region for a temperature range of 20 – 100 K that will be later used to characterize the HTS-CCs. Results for Rutile and Strontium Titanate are presented., L’objectiu principal d’aquest projecte és dissenyar, fabricar i provar un ressonador capaç de mesurar les propietats requerides de diferents mostres dielèctriques en la regió de microones per a un rang de temperatura entre 20 - 100 K que posteriorment s’utilitzarà per caracteritzar els HTS-CCs. Es presenten resultats per al Rútil i Titanat d’Estronci., El objetivo principal de este proyecto es diseñar, fabricar y probar un resonador capaz de medir las propiedades requeridas de diferentes muestras dieléctricas en la región de microondas para un rango de temperatura entre 20 - 100 K que luego se utilizará para caracterizar los HTS-CCs. Se presentan resultados para el Rutilo y Titanato de Estroncio.

A thorough microwave response study of high temperature superconductors, considered as an alternative beam screen coating, has become integral in the design decisions for CERN’s future research infrastructure. Here, we present the surface resistance Rs of various REBa2Cu3O7-x (RE = rare earth) coated conductors available in large scale as a function of magnetic field in a broad temperature range measured by a Hakki–Coleman type resonator with resonant frequency ¿˜8GHz. Analysis of the high frequency dissipation supported by DC transport characterization reveals the vortex dynamics in thick REBa2Cu3O7-x films. Determined microscopic vortex parameters span over a wide range of magnitudes and reflect the relevance of the superconducting layer’s microstructure. We demonstrate that the depinning frequencies ¿0 surpass ¿, which confirms the operation in high performing, low dissipation pinning regime at measurement conditions. Surface impedance extrapolation to FCC-hh conditions points towards a significant outperformance of copper by coated conductors in terms of surface resistance. The surface resistance margins would open up potential ways for a more efficient frontier circular collider., Authors acknowledge the support and samples provided by Bruker HTS GmbH, Fujikura Ltd., Sunam Co., SuperOx, SuperPower Inc. and THEVA Dünnschichttechnik GmbH. Authors acknowledge CERN funding FCCGOV- CC-0073/ 1724666/KE3359, MAT2014-51778-C2 COACHSUPENERGY, RTI2018-095853-B-C21 SuMaTe from MICINN and co-financing by the European Regional Development Fund; 2017-SGR 1519 from Generalitat de Catalunya and COST Action NANOCO-HYBRI (CA16218) from EU. Authors acknowledge Prof. Ruggero Vaglio for sharing his knowledge on vortex physics inferable from surface resistance measurements in several project meetings. ICMAB authors acknowledge the Center of Excellence award Severo Ochoa SEV-2015-0496 and its Future Interdisciplinary Projects action. UPC funding was provided through the Unit of Excellence María de Maeztu MDM2016-0600. JG acknowledges MSCA-COFUND-2014-665919 for financial support. AR acknowledges MSCA-COFUND-2016-754397 for PhD grant and would like to thank Prof. Enrico Silva, Prof. Nicola Pompeo, Dr. Kostiantyn Torokhtii and Andrea Alimenti from University Roma Tre for hosting him in their laboratory part of which were most helpful discussions on RF measurement techniques., Peer Reviewed, Postprint (published version)

Measuring the electrical surface resistance of 2D materials without contact can provide a method for obtaining their intrinsic characterisation. The aim of this paper is to show that a rutile dielectric resonator (RDR) can be used to measure the electrical surface resistance of conducting coatings deposited on substrates, at the resonance frequency. Moreover, it is known that the substrate exerts a strong influence capable of intrinsically modify the properties of the 2D materials, as found in graphene. The RDR method is used for different samples of metals (Cu, Mo, Ti, brass), carbon nanotubes (bucky paper), a film of compacted graphene flakes, a film of compacted graphene oxide flakes and graphene obtained by CVD on different substrates (SiO2/Si, quartz and PET). The results show that reasonable values can be obtained for thin conducting materials with a thickness of not less than a few micrometers. In the case of graphene grown on a substrate, the presence of graphene is clearly detected but the resistivity value cannot be extracted., Peer Reviewed, Postprint (author's final draft)

In response to the 2013 Update of the European Strategy for Particle Physics (EPPSU), the Future Circular Collider (FCC) study was launched as a world-wide international collaboration hosted by CERN. The FCC study covered an energy-frontier hadron collider (FCC-hh), a highest-luminosity high-energy lepton collider (FCC-ee), the corresponding 100 km tunnel infrastructure, as well as the physics opportunities of these two colliders, and a high-energy LHC, based on FCC-hh technology. This document constitutes the third volume of the FCC Conceptual Design Report, devoted to the hadron collider FCC-hh. It summarizes the FCC-hh physics discovery opportunities, presents the FCC-hh accelerator design, performance reach, and staged operation plan, discusses the underlying technologies, the civil engineering and technical infrastructure, and also sketches a possible implementation. Combining ingredients from the Large Hadron Collider (LHC), the high-luminosity LHC upgrade and adding novel technologies and approaches, the FCC-hh design aims at significantly extending the energy frontier to 100 TeV. Its unprecedented centre-of-mass collision energy will make the FCC-hh a unique instrument to explore physics beyond the Standard Model, offering great direct sensitivity to new physics and discoveries., Peer Reviewed, Postprint (published version)

There is an increasing need for safe and simple techniques for sensing devices and prostheses implanted inside the human body. Microwave wireless inspection may be an appropriate technique for it. The implanted device may have specific characteristics that allow to distinguish it from its environment. A new sensing technique based on the principle of differential resonance is proposed and its basic parameters are discussed. This technique allows to use the implant as a signal scattering device and to detect changes produced in the implant based on the corresponding change in its scattering signature. The technique is first tested with a canonic human phantom and then applied to a real in vivo clinical experiment to detect coronary stents implanted in swine animals, Peer Reviewed, Postprint (published version)

We review the physics opportunities of the Future Circular Collider, covering its e+e-, pp, ep and heavy ion programmes. We describe the measurement capabilities of each FCC component, addressing the study of electroweak, Higgs and strong interactions, the top quark and flavour, as well as phenomena beyond the Standard Model. We highlight the synergy and complementarity of the different colliders, which will contribute to a uniquely coherent and ambitious research programme, providing an unmatchable combination of precision and sensitivity to new physics., Peer Reviewed, Postprint (published version)

In response to the 2013 Update of the European Strategy for Particle Physics, the Future Circular Collider (FCC) study was launched, as an international collaboration hosted by CERN. This study covers a highest-luminosity high-energy lepton collider (FCC-ee) and an energy-frontier hadron collider (FCC-hh), which could, successively, be installed in the same 100 km tunnel. The scientific capabilities of the integrated FCC programme would serve the worldwide community throughout the 21st century. The FCC study also investigates an LHC energy upgrade, using FCC-hh technology. This document constitutes the second volume of the FCC Conceptual Design Report, devoted to the electron-positron collider FCC-ee. After summarizing the physics discovery opportunities, it presents the accelerator design, performance reach, a staged operation scenario, the underlying technologies, civil engineering, technical infrastructure, and an implementation plan. FCC-ee can be built with today’s technology. Most of the FCC-ee infrastructure could be reused for FCC-hh. Combining concepts from past and present lepton colliders and adding a few novel elements, the FCC-ee design promises outstandingly high luminosity. This will make the FCC-ee a unique precision instrument to study the heaviest known particles (Z, W and H bosons and the top quark), offering great direct and indirect sensitivity to new physics., Peer Reviewed, Postprint (published version)

The recent emergence of the 3D printing technology, also called additive manufacturing (AM), and its more than obvious possible application for microwaves purposes leads to a potential improvement in the field of low-cost high-performance mass production. This thesis aims to evaluate such 3D printing manufacturing processes by making a comparison between devices manufactured by the 3D printing procedure and their equivalent devices manufactured with other well-known manufacturing processes. The device chosen as the object of comparison is a half-wave end coupled resonator filter. For the implementation of these filters, the resonators are first designed in each of the manufacturing technologies to be compared, making emphasis on 3D printing. From these resonators, the quality factor is obtained, from which it is possible to predict the response of each filter. Results are evaluated in order to validate such novel manufacturing technique.

The surface resistance of state-of-the-art REBa2Cu3O7-x coated conductors has been measured at 8 GHz versus temperature and magnetic field. We show that the surface resistance of REBa2Cu3O7-x strongly depends on the microstructure of the material. We have compared our results to those determined by the rigid fluxon model. The model gives a very good qualitative description of our data, opening the door to unravel the effect of material microstructure and vortex interactions on the surface resistance of high temperature superconductors. Moreover, it provides a powerful tool to design the best coated conductor architecture that minimizes the in-field surface resistance. We have found that the surface resistance of REBa2Cu3O7-x at 50 K and up to 9 T is lower than that of copper. This fact poses coated conductors as strong candidate to substitute copper as a beamscreen coating in CERN's future circular collider. To this end we have also analyzed the secondary electron yield (SEY) of REBa2Cu3O7-x and found a compatible coating made of sputtered Ti and amorphous carbon that decreases the SEY close to unity, a mandatory requirement for the beamscreen chamber of a circular collider in order to prevent the electron-cloud phenomenon., Peer Reviewed, Postprint (author's final draft)

© 2019 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes,creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works., In this letter, a three-dimensional (3-D) printed compact ultrawideband (UWB) extended gap ridge horn (EGRH) antenna designed to be used for biological measurements of the human body is described. The operational frequency covers the microwave band of interest from 0.5 to 3.0 GHz (for an S 11 under -7 dB). The 3-D printed EGRH antenna is dielectrically matched to the permittivity of the human body, and because of its compactness, it can be visualized as a general-purpose microwave probe among the RF biomedical community. The probe has proven its capability as a pass-through propagation sensor for different parts of the human body and as a sensor detecting a 1 cm diameter object placed inside an artificial head phantom., Peer Reviewed, Postprint (author's final draft)

In response to the 2013 Update of the European Strategy for Particle Physics (EPPSU), the Future Circular Collider (FCC) study was launched as a world-wide international collaboration hosted by CERN. The FCC study covered an energy-frontier hadron collider (FCC-hh), a highest-luminosity high-energy lepton collider (FCC-ee), the corresponding 100 km tunnel infrastructure, as well as the physics opportunities of these two colliders, and a high-energy LHC, based on FCC-hh technology. This document constitutes the third volume of the FCC Conceptual Design Report, devoted to the hadron collider FCC-hh. It summarizes the FCC-hh physics discovery opportunities, presents the FCC-hh accelerator design, performance reach, and staged operation plan, discusses the underlying technologies, the civil engineering and technical infrastructure, and also sketches a possible implementation. Combining ingredients from the Large Hadron Collider (LHC), the high-luminosity LHC upgrade and adding novel technologies and approaches, the FCC-hh design aims at significantly extending the energy frontier to 100 TeV. Its unprecedented centre of-mass collision energy will make the FCC-hh a unique instrument to explore physics beyond the Standard Model, offering great direct sensitivity to new physics and discoveries., Peer Reviewed, Postprint (published version)

Rutile resonators have been used in the past to characterize high-temperature superconductors. In this work we describe a novel use of this type of resonator: the characterization of surface resistance in metal coatings deposited on plastic substrates at 9.1 GHz. A very small sample surface (about 1 cm 2 ) is required due to the high permittivity of rutile. We describe the use of the resonator to analyze pairs of small samples and to analyze the homogeneity of a sample set diced from a larger metallized surface. We also show a novel experimental method to determine the geometrical factors in dielectric resonators., Peer Reviewed, Postprint (published version)

The manufacturing of prototype of an offset parabolic reflector to operate at 120 GHz is presented. The paper describes the different metallization options to achieve a good performance., Peer Reviewed, Postprint (published version)

Some conditions are well known to be directly associated with stent failure, including in-stent re-occlusion and stent fracture. Currently, identification of these high-risk conditions requires invasive and complex procedures. This study aims to assess microwave spectrometry (MWS) for monitoring stents non-invasively. Preliminary ex vivo data are presented to move to in vivo validation. Fifteen mice were assigned to receive subcutaneous stent implantations (n¿=¿10) or sham operations (n¿=¿5). MWS measurements were carried out at 0, 2, 4, 7, 14, 22, and 29 days of follow-up. Additionally, 5 stented animals were summited to micro-CT analyses at the same time points. At 29 days, 3 animals were included into a stent fracture subgroup and underwent a last MWS and micro-CT analysis. MWS was able to identify stent position and in-stent stenosis over time, also discerning significant differences from baseline measures (P¿<¿0.001). Moreover, MWS identified fractured vs. non-fractured stents in vivo. Taken together, MWS emerges as a non-invasive, non-ionizing alternative for stent monitoring. MWS analysis clearly distinguished between in-stent stenosis and stent fracture phenomena., Peer Reviewed, Postprint (published version)

This Thesis belongs to a scientific project realized by the TRYO Company, which is part of the aerospace sector of the SENER Group. It describes the design, analysis, measurements and results of one of the back-end modules EQM (Elecrical Qualification Model) of ICI (Ice Cloud Imager) radiometer, which is embarked in the satellites which form the space mission of MetOp-SG (MetOp Second Generation Program). The back-end module will operate at the sub-millimetre wave band of 325GHz, after down converters and contains the last part of the channels: amplifiers, filters, detectors and video section. The methodology and the development of the project start from customer requirements, the design of prototypes which will be integrated of the back-end and the detailed design, tuning, measurements, and validation of the main tests. Electromagnetic simulations tools as ADS [1] and HFSS [2] are used and also instrumentation as Vectorial Network Analyzers, Spectrum Analyzers, Noise Figure Analyzers, Noise Generators, oscilloscopes and both data acquisition and data processing software. We expose the final results and the statement of compliance of the project requirements. Finally, the measurements and the performance of the back-end module are shown and we draw our conclusions.

This is the accepted version of the following article: Guardiola, M. , Buitrago, S. , Fernández‐Esparrach, G. , O'Callaghan, J. M., Romeu, J. , Cuatrecasas, M. , Córdova, H. , González Ballester, M. Á. and Camara, O. (2018), Dielectric properties of colon polyps, cancer, and normal mucosa: Ex vivo measurements from 0.5 to 20 GHz. Med. Phys., 45: 3768-3782. doi:10.1002/mp.13016, which has been published in final form at https://aapm.onlinelibrary.wiley.com/doi/pdf/10.1002/mp.13016. This article may be used for non-commercial purposes in accordance with the Wiley Self-Archiving Policy [http://olabout.wiley.com/WileyCDA/Section/id-820227.html]., Colorectal cancer is highly preventable by detecting and removing polyps, which are the precursors. 20 Currently, the most accurate test is colonoscopy, but still misses 22% of polyps due to visualization limitations. In this paper we preliminary assess the potential of microwave imaging and dielectric properties (e.g. complex permittivity) as a complementary method for detecting polyps and cancer tissue in the colon. The dielectric properties of biological tissues have been used in a wide variety of applications, including safety assessment of wireless technologies and design of medical diagnostic or therapeutic techniques 25 (microwave imaging, hyperthermia and ablation). The main purpose of this work is to measure the complex permittivity of different types of colon polyps, cancer and normal mucosa in ex vivo human samples to study if the dielectric properties are appropriate for classification purposes., Peer Reviewed, Postprint (author's final draft)

This thesis studies the possibility of using CPW to measure the permittivity of materials. For this purpose, the material to be measured (MUT) is deposited on the CPW and measurements of S parameters are made from which the characteristics of the MUT can be determined. Furthemore we had to find the equivalent generic line using ADS and made the data fitting of the measurements taken in the laboratory with the VNA (Vector Network Analyzer) using the optimization tools of this sotware. We also tried to simulate the CPW with the different samples on the top and study the SParameters in those cases. To recreate this system we use HFSS. Finally we analyze the data obtained, extract the capacity and inductance of the line and study how they vary according to the permittivity of the sample. We try to perform these measurements in the band from 1 to 50 GHz but due to problems with the software used we decided to reduce the bandwith to 20 GHz., Aquest Treball de Fi de Grau estudia la possibilitat d'utilitzar línies CW per mesurar la permitivitat de materials. Per això es disposa d'un material a mesurar (MUT) sobre la CPW i es realitzen mesures dels paràmetres S a partir dels cuals es pot determinar les característiques del MUT. Vam haver de trobar la línia genérica equivalent de l'ADS i fer l'ajust de dades, respecte de les mesures adquirides emprant l'analitzador de xarxes vectorials, amb les eines d'optimització d'aquest programa. També vam tractar de simular la CPW amb les diferents mostres a la part superior i estudiar els paràmetres S en aquests casos. Per crear aquest sistema vam utilitzar HFSS. Finalment vam haver d'analitzar les dades obtingudes, extreure la capacitat i la inductància de la línia i estudiar com varien d'acord amb la permitivitat de la mostra. Vam tractar de fer aquests mesuraments a la banda d'1 a 50 GHz, però a causa de problemes amb el software utilitzat vam decidir reduir l'ample de banda fins a 20 GHz., Este Trabajo Fin de Grado estudia la posibilidad de utilizar líneas CPW para la medida de permitividad de materiales. Para ello se dispone el material a medir (MUT) sobre la CPW y se realizan medidas de parámetros S a partir de los cuales se puede determinar las características del MUT. Además tuvimos que encontrar la línea genérica equivalente de ADS y realizar el ajuste de datos, respecto de las mediciones tomadas en el laboratorio con el VNA (Vector Network Analyzer), usando las herramientas de optimización de este programa. También tratamos de simular la CPW con las diferentes muestras en la parte superior y estudiar los parámetros S en esos casos. Para recrear este sistema usamos HFSS. Finalmente analizar los datos obtenidos, extraer la capacidad e inductancia de la línea y estudiar cómo varían según la permitividad de la muestra. Intentamos realizar estas mediciones en la banda de 1 a 50 GHz pero debido a problemas con el software utilizado decidimos reducir el ancho de banda hasta 20 GHz.

©2017 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works., This paper presents a phenomenological equivalent circuit to model the phenomenon occurring when a section of superconducting transmission line transits from a superconducting state to a normal state. This phenomenon allows the use of superconductors for the design of autolimiting structures based on superconducting transmission line sections. Although this autolimiting effect happens when the current density achieved in the superconductor exceeds the critical current inherent to the superconducting material, heating effects also play a significant role in this behavior. The equivalent circuit presented in this work accounts for both electric and thermal effects, and the interaction between them. The circuit model is then used for the evaluation of a practical microwave and frequency selective IMUX configuration., Peer Reviewed, Postprint (author's final draft)

The main objective of this thesis is to characterize, using the ADS software, the coaxial probe provided by the faculty ETSETB and utilize such probe in order to calculate the permittivity of different materials, El objetivo principal de esta tesis el de caracterizar, con el programa ADS, la sonda coaxial proporcionada por la facultad de la ETSETB y utilizar-la para el calculo de la permitividad de diferentes materiales., L'objectiu d'aquesta tesis es el de caracteritzar, amb el programa ADS, la sonda coaxial proporcionada per la facultat de l'ETSETB I utilitzar-la per calcular la permitivitat en diferents materials

This thesis comprises four microstrip resonator designs simulated with ADS and HFSS. The designs subsequently have been physically implemented with the final goal of obtaining the real part of the permittivity of the samples; both solid and liquid. Two different methods have been used, the shift of the resonance frequency and the variation of the mutual coupling between two resonators., Esta tesis consta de cuatro diseños resonadores microstrip simulados con ADS y HFSS que posteriormente han sido implementados físicamente con el objetivo final de obtener la parte real de la permitividad de muestras tanto sólidas como líquidas a través de dos métodos diferentes, el desplazamiento de la frecuencia de resonancia y la variación del acoplamiento mutuo entre dos resonadores., Aquesta tesis consta de quatre dissenys ressonadors microstrip simulats amb ADS i HFSS que posteriorment han estat implementats físicament amb l'objectiu final d'obtenir la part real de la permitivitat de mostres tant sòlides com líquides a través de dos mètodes diferents, el desplaçament de la freqüència de ressonància i la variació de l'acoblament mutu entre dos ressonadors.

La investigación para el muestreo de muestras biológicas ha avanzado buscando sacar la mejor sensibilidad i métodos que no dañen las muestras o incluso las destruyan. Una rama de métodos que es posible que puedan llegar a un buen compromiso entre estos dos son los sensores de microondas que obtienen datos de la muestra analizando su permisividad dieléctrica y que no provocan ningún daño en la muestra además de proporcionar una buena sensibilidad. En este proyecto nos centramos en investigar un tipo de tecnología de microondas llamada SIW que puede reproducir una guía de ondas en un tamaño mucho más pequeño. El objetivo era demostrar que con un SIW se podía crear el equivalente a un sensor de microondas con sus mismas prestaciones pero a escala más reducida y más fácil de fabricar. Los resultados obtenidos con las simulaciones y las pruebas nos dan buenas señales para implementar esta tecnología para sensores. Podemos determinar que aunque el rango de operación y las perdidas limitan el buen funcionamiento, es posible determinar la permisividad comparando los datos medidos con las simulaciones y documentos de anteriores investigaciones., The research for sampling biological samples has been moving forward looking for to get out the best of sensibility and methods that don't damage the samples or rather destroy them. A branch of methods that can possible arrive a good compromise between those two are microwave sensors that get data from permittivity analysis and don't cause any sample damage and also have a good sensibility. In this project we were focusing on researching a type of microwave technology called SIW that is able to reproduce a waveguide in a much smaller size. The aim was to prove that with a SIW we could create an equivalent waveguide sensor that had the same performance but much smaller size and is easier to create. The results obtained with simulations and testing give us a good approach to implement this technology for sensors. We determine that although the range of operation and losses that restrict a good performance, it is possible to determine the permittivity by comparing measured data with simulations and previous research papers., La investigació per al mostreig de mostres biològiques ha avançat buscant treure millor sensibilitat i els mètodes que no facin malbé les mostres o més aviat destruir-les. Un seguit de mètodes que es possible que arribin a un bon compromís entre aquestes dues són els sensors de microones que obtenen dades de la mostra analitzant la seva permitivitat i no provoquen cap dany en la mostra a més de proporcionar una bona sensibilitat. En aquest projecte ens vam centrar en investigar un tipus de tecnologia de microones anomenada SIW que pot reproduir una guia d'ones en una mida molt més petita. L'objectiu era demostrar que amb un SIW es podia crear un equivalent a un sensor fet amb una guia d'ones amb les mateixes prestacions però molt més petit i més fàcil de fabricar. Els resultats obtinguts amb les simulacions i les proves ens donen bons indicadors per implementar aquesta tecnologia per a sensors. Podem determinar que encara que el rang d'operació i pèrdues que limiten el bon funcionament, és possible determinar la permitivitat comparant les dades mesurades amb les simulacions i documents anteriors recerques.

Measurement of permittivity of biological samples at microwave frequencies has proven useful for many purposes going from determining the state (ripeness) of a piece of fruit, to evaluating the presence of a cancer in a breast sample tissue. In this project a comparison between two methods (resonant cavities and coaxial probe) will be performed in order to asses its feasibility to be used in the diagnosis of colonorectal and liver cancer., This thesis shows the capacity of a coaxial probe to measure permittivity in biological samples. The project’s aim is to study the optimal parameters which the coaxial probe has to have in order to perform measurements as accurately as possible. Some simulations are presented showing the little differences between the real measurements and simulated ones with Advanced Simulation Design (ADS) software. These measurements have been done in air and known materials at the beginning in order to check that the set-up worked properly and they have been finally performed in biological samples., Esta tesis muestra la capacidad de una sonda coaxial para medir permitividad en muestras biológicas. El objetivo de este proyecto es estudiar los parámetros óptimos que la sonda debería tener para poder realizar medidas de la forma más precisa posible. Las medidas presentadas muestran las pequeñas diferencias entre las medidas hechas directamente en los materiales y las simuladas con el programa Advanced Simulation Design (ADS). Primeramente, estas medidas han sido realizadas en aire y materiales conocidos para así ser capaces de comprobar el correcto funcionamiento de la sonda y, de este modo, poder realizarlas en muestras biológicas., Aquesta tesi mostra la capacitat d’una sonda coaxial de mesurar permitivitat en mostres biològiques. L’objectiu d’aquest projecte és estudiar els paràmetres òptims que la sonda hauria de tenir per poder realitzar mesures de la forma més acurada possible. Les mesures presentades mostren les petites diferencies entre les mesures fetes directament als materials i les simulades amb el programa Advanced Simulation Design (ADS). Primerament, aquestes mesures han sigut fetes en aire i materials coneguts per poder ser capaços de comprovar el correcte funcionament de la sonda i, d’aquesta manera, poder fer finalment les mesures en mostres biològiques.

This paper presents a phenomenological equivalent circuit to model the phenomenon occurring when a section of superconducting transmission line transits from a superconducting state to a normal state. This phenomenon allows the use of superconductors for the design of autolimiting structures based on superconducting transmission line sections. Although this autolimiting effect happens when the current density achieved in the superconductor exceeds the critical current inherent to the superconducting material, heating effects also play a significant role in this behavior. The equivalent circuit presented in this work accounts for both electric and thermal effects, and the interaction between them. The circuit model is then used for the evaluation of a practical microwave and frequency selective IMUX configuration., Peer Reviewed, Postprint (published version)

The specifications of the European Space Agency for intermediate frequency (IF) filters call for filters having a large bandwidth relative to their center frequency. The project proposed should contribute to the design and simulation of these filters based on the group's previous experience (see www.tsc.upc.edu/lossyfilters) _______________ Les especificacions de l?Agencia Espacial Europea per a filtres de freqüència IF en satèl·lits de comunicacions demanen grans amples de banda respecte a la freqüència central del filtre. El projecte que es proposa ha de contribuir al d, Usage and popularity growth of communications satellites has increased the interest on filter synthesis research. Nowadays, the improvement of the trade-off between size, weight, cost and performance is the golden rule. Innovations have been obtained by means of new transmission supports, effective but expensive, and new topologies and geometries. Focusing on coupled resonator filters, new possibilities of space-filling fractals has been anal- ysed. Specifically, Hilbert and Moore fractals have been employed as geometrical patterns for microstrip resonators. Without any closed analytical model, it has been created the layouts, simulated and analysed that resonators using MATLAB and ADS Momentum. Its dependence with the most represen- tative physical parameters and new design features that can offer have been also assessed. Finally, modifying initial resonators, some application cases have been presented. With this examples, the versatility of the suggested geometries has been shown in order to desplace resonances keeping the desired one aligned., El creciente uso y popularidad de los satélites de comunicaciones ha intensificado el interés en avanzar en la síntesis de filtros. En la actualidad, obtener la mejor relación entre tamaño, peso, coste y prestaciones es la regla de oro. La innovación ha avanzado en nuevos soportes de transmisión, costosos pero eficaces, y en nuevas propuestas de topologías y geometrías. Centrándonos en técnicas de diseño de filtros mediante resonadores, se han estudiado las posibilidades de los fractales space-filling. En concreto, los fractales de Hilbert y Moore se emplean como patrones geométricos de resonadores microstrip. Sin emplear modelos analíticos cerrados, mediante MATLAB y ADS Momentum se han creado los layouts, simulado y analizado dichos resonadores. Se ha estudiado su dependencia con los parámetros físicos más representativos y las opciones de diseño que ofrecen. Finalmente, modificando los resonadores de partida, se presentan casos de aplicación. Con estos se muestra la versatilidad de las geometrías propuestas para desplazar las resonancias preservando una concreta., El creixent ús i popularitat dels satèl·lits de comunicacions ha intensificat l’interès per avançar en la síntesi de filtres. En la actualitat, obtenir una millor relació entre tamany, pes, cost i prestacions és la regla d’or. La innovació ha fet avenços en nous suports de transmissió, costosos però eficaços, i en noves propostes de topologies i geometries. Centrant-nos en tècniques de disseny de filtres amb ressonadors, s’han estudiat les possibilitats dels fractals space-filling. En concret, els fractals de Hilbert i Moore s’empren com patrons geomètrics de ressonadors microstrip. Sense emprar models analítics tancats, mitjançant MATLAB i ADS Momentum s’han creat els layouts, simulat i analitzat aquests ressonadors. S’ha estudiat la seva dependència amb els paràmetres físics més representatius i les opcions de disseny que ofereixen. Finalment, modificant els ressonadors inicials, es presenten casos d’aplicació. Amb aquests es mostra la versatilitat de les geometries proposades per desplaçar ressonancies preservant una concreta.

Resolved

Stents are medical devices that are implanted inside blood vessels to restore partial occlusions (stenosis). These devices (Fig. 1) are made of a frame of filaments (usually metallic) following a geometry that allows the frame to expand when a radial pressure is exerted. To implant them, stents are crimped around inflatable balloon catheters which are used to position the stent at the vessel occlusion. Once properly placed, the balloon is inflated and the stent is fixed to the vessel wall, restoring the appropriate vessel lumen. The balloon can be subsequently deflated and