Now showing items 1-16 of 16

    • Accurate determination of dielectric properties in small, high-permittivity dielectric cylinders 

      Tagdulang, Nikki; Krkotic, Patrick; Díez, A.; Pont Montaner, Montserrat; O'Callaghan Castellà, Juan Manuel (Institute of Electrical and Electronics Engineers (IEEE), 2022)
      Conference lecture
      Open Access
      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 ...
    • Algorithm for resonator parameter extraction from symmetrical and asymmetrical transmission responses 

      Krkotic, Patrick; Gallardo Moix, Queralt; Tagdulang, Nikki; Pont Montaner, Montserrat; O'Callaghan Castellà, Juan Manuel (IEEE Microwave Theory and Techniques Society, 2021-08)
      Article
      Open Access
      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 ...
    • Characterisation of copper and stainless steel surfaces treated with laser ablation surface engineering 

      Hannah, Adrian N.; Krkotic, Patrick; Valizadeh, Reza; Malyshev, Oleg; Mutch, J.; Whitehead, David J.; Pont, Montse; O'Callaghan Castellà, Juan Manuel; Dhanak, Vinod R. (2021-07)
      Article
      Open Access
      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 ...
    • Coated conductor technology for the beamscreen chamber of future high energy circular colliders 

      Puig Molina, Teresa; Krkotic, Patrick; Romanov, Artur; O'Callaghan Castellà, Juan Manuel; Gutiérrez Royo, Joffre (2019-09-01)
      Article
      Open Access
      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 ...
    • Contactless electrical resistance of 2D materials using a rutile resonator 

      Arcos Gutiérrez, David; Krkotic, Patrick; O'Callaghan Castellà, Juan Manuel; Pont, Montse; Ametller Congost, Lluís; Ferrer Anglada, Núria (2019-12-12)
      Article
      Open Access
      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 ...
    • Dielectric resonator to measure surface resistance of accelerator components at room temperature and 77 K 

      Brunner, Kristóf; Krkotic, Patrick; Costa Pinto, Pedro; Gibbons Díaz-Rato, Eduardo; Pfeiffer, Stephan; Vollenberg, Wilhelmus; Calatroni, Sergio; Barna, Dániel; Pont Montaner, Montserrat; O'Callaghan Castellà, Juan Manuel (American Physical Society (APS), 2023-08)
      Article
      Open Access
      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 ...
    • Evaluation of the nonlinear surface resistance of REBCO coated conductors for their use in the FCC-hh beam screen 

      Krkotic, Patrick; Romanov, Artur; Tagdulang, Nikki; Telles, Guilherme; Puig Molina, Teresa; Gutiérrez Royo, Joffre; Granados García, Xavier; Calatroni, Sergio; Pérez, Francis; Pont Montaner, Montserrat; O'Callaghan Castellà, Juan Manuel (2022-01-07)
      Article
      Open Access
      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 ...
    • Evaluation of the surface impedance of ReBCO coated conductors and requirements for their use as beam screen materials for the FCC-hh 

      Krkotic, Patrick (Universitat Politècnica de Catalunya, 2022-11-25)
      Doctoral thesis
      Open Access
      (English) The Future Circular Hadron Collider (FCC-hh) is a proposal for a 100-kilometre-long particle accelerator with collision energy substantially higher than previous colliders to expand the Large Hadron Collider (LHC) ...
    • FCC physics opportunities: future circular collider conceptual design report volume 1 

      Abada, A.; Abbrescia, M.; AbdusSalam, S. S.; O'Callaghan Castellà, Juan Manuel; Krkotic, Patrick (Springer, 2019-06-05)
      Article
      Open Access
      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, ...
    • FCC-hh: the hadron collider: future circular collider conceptual design report volume 3 

      Abada, A.; Abbrescia, M.; AbdusSalam, S. S.; O'Callaghan Castellà, Juan Manuel; Krkotic, Patrick (Springer, 2019-07-01)
      Article
      Open Access
      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 ...
    • HE-LHC: the High-Energy Large Hadron Collider: Future Circular Collider Conceptual Design Report Volume 4 

      Abada, A.; Abbrescia, M.; AbdusSalam, S. S.; O'Callaghan Castellà, Juan Manuel; Krkotic, Patrick (Springer, 2019-07-01)
      Article
      Open Access
      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 ...
    • High frequency response of thick REBCO coated conductors in the framework of the FCC study 

      Romanov, Artur; Krkotic, Patrick; Telles, Guilherme; O'Callaghan Castellà, Juan Manuel; Pont, Montse; Pérez, Francis; Granados García, Xavier; Calatroni, Sergio; Puig Molina, Teresa; Gutiérrez Royo, Joffre (Nature, 2020-07-23)
      Article
      Open Access
      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 ...
    • Performance of high-temperature superconducting REBCO coated conductors under synchrotron irradiation for future circular colliders 

      Krkotic, Patrick; Traver Ramos, Oriol; Tagdulang, Nikki; Calatroni, Sergio; O'Callaghan Castellà, Juan Manuel; Pont Montaner, Montserrat (Institute of Physics (IOP), 2023-10-01)
      Article
      Open Access
      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 ...
    • Potential impedance reduction by REBCO coated conductors as beam screen coating for the future circular hadron collider 

      Krkotic, Patrick; Tagdulang, Nikki; Calatroni, Sergio; O'Callaghan Castellà, Juan Manuel; Pont Montaner, Montserrat (2022-12)
      Article
      Open Access
      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 ...
    • RF characterisation of new coatings for future circular collider beam screens 

      Krkotic, Patrick; Pérez, Francis; Pont Montaner, Montserrat; Tagdulang, Nikki; Calatroni, Sergio; O'Callaghan Castellà, Juan Manuel; Granados García, Xavier; Gutiérrez Royo, Joffre; Puig Molina, Teresa; Romanov, Artur; Telles, Guilherme; Hannah, Adrian N.; Malyshev, Oleg; Valizadeh, Reza; Whitehead, David J. (Joint Accelerator Conferences Website (JACoW), 2021)
      Conference lecture
      Open Access
      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 ...
    • Small footprint evaluation of metal coatings for additive manufacturing 

      Krkotic, Patrick; Aguasca Solé, Alberto; O'Callaghan Castellà, Juan Manuel (Institute of Electrical and Electronics Engineers (IEEE), 2018)
      Conference lecture
      Restricted access - publisher's policy
      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 ...