ATLAS Detector

IFAE Research Groups

Collider Physics Group

  • Collider Physics Group

    CERN’s Large Hadron Collider (LHC) delivered the first high-energy proton-proton collisions in 2010, opening a new energy frontier in particle physics. ATLAS is one of the four large detectors at the LHC involving about 3000 scientists. With a 25-year involvement in the ATLAS experiment, IFAE has strongly contributed to a broad spectrum of topics critical to the scientific exploitation of the experiment

    The Collider Physics group at IFAE is led by M. Bosman.

    The ATLAS Tile Hadronic Calorimeter (TileCal)

    IFAE played a central role in the design, construction and commissioning of the Tile hadronic Calorimeter (TileCal), finished in 2009. Since 2010, IFAE strongly contributes to various aspects of the TileCal operation, data reconstruction, calibration, data quality monitoring, and luminosity measurement. IFAE researchers often act as TileCal run coordinators. During the last years the group has led the R&D for the new structure hosting the upgraded front-end electronics, needed for the high luminosity LHC (HL-LHC) period starting in 2027. The production of the new structures started in 2019 and is expected to last 3 years.

    ATLAS Detector
    ATLAS Detector Credit: Maximilien Brice, CERN

    The ATLAS Trigger and Data Aquisistion (TDAQ)

    IFAE has contributed to the development and operation of the data acquisition and event selection system (trigger), critical for an efficient selection of the most interesting collisions. IFAE was one of three groups developing the software infrastructure of the high-level trigger and held several coordinating responsibilities within the ATLAS trigger group. IFAE also played a key role in developing the algorithms for the selection of events with tau leptons, later extended to jet triggers. In order to cope with the higher luminosity of Run 2 (2015-2018), ATLAS installed a new processor to perform real-time event selection based on topological variables. IFAE made major contributions to the simulation of the processor, its commissioning and validation with data. Moreover, IFAE contributed to the operations of the whole trigger system with the overall coordination of the trigger menu. The trigger work at IFAE will continue in preparation for the new Run 3 scheduled for spring 2022.

    ATLAS Detector
    ATLAS Detector Credit: Claudia Marcelloni , CERN

    Physics Analysis Program

    The institute deployed a strong and rich physics analysis program at the LHC, expanding from precise Standard Model background measurements to Higgs boson physics. During Run 2, when LHC collided protons at a center-of-mass energy of 13 TeV, IFAE developed a broad program of searches for new phenomena, including dark matter, invisible Higgs boson decays, supersymmetry, compositeness, new heavy Higgs bosons, as well as precise measurements of the interactions between the top and bottom quarks and the Higgs boson. IFAE, which represents about 1% of ATLAS, directly contributes to about 10% of ATLAS publications. IFAE researches have held a number of physics-related coordination positions. Most notably, A. Juste is the current co-coordinator of the ATLAS Exotics Physics Working Group.

    ATLAS Event display
    ATLAS Event display Hbb Credit: ATLAS

    Data processing of the LHC data

    IFAE is a main actor in the data processing of the LHC data. In 2003, IFAE and CIEMAT founded the Port d’Informació Científica (PIC), one of 13 LHC Tier-1 data centers in the world and the only one in Spain. As such, PIC participates in the overall effort of processing and distributing the tens of PB of data the LHC produces every year. Year after year, PIC, which operates 24/7, is listed in the top three of Tier-1 centers in terms of reliability.

    PIC
    PIC Datacenter Credit: PIC

    3D silicon pixel sensors for ATLAS

    IFAE in collaboration with the CNM center in the UAB campus led the development of the ultra-radiation-hard 3D silicon pixel sensors for ATLAS. The institute made key contributions to the current detector systems based on this technology: providing 3D sensors for the innermost pixel layer (IBL) in 2014 and constructing in 2016 the first stations for the ATLAS Forward Protons (AFP) tracking system, finished in 2020. Recently, the design of the 3D sensors has been adapted to satisfy the HL-LHC requirements, and the technology has been selected for the innermost layer of the new ATLAS tracking system. IFAE is now preparing to produce the pixel modules and deliver them to CERN in the mid 2020s. This is arguably the most demanding piece of instrumentation of ATLAS: a 250-um-thick silicon sensor that will reside 3cm away from the interaction point and that has to provide excellent position resolution during many years of LHC operation in a high radiation environment.

    ATLAS IBL
    IBL installation into the inner detector of the ATLAS Experiment side C Credit: Claudia Marcelloni/CERN

    High Granularity Timing Detector (HGTD)

    IFAE has been deeply involved in the R&D effort to design and fabricate a timing detector to mitigate the effect of pile-up at the HL-LHC. Using timing, one can identify the origin of the reconstructed tracks, thus reducing the effect of overlapping collisions. IFAE proposed the Low Gain Avalanche Detector (LGAD) technology developed at CNM to be used in a High Granularity Timing Detector (HGTD), demonstrating that LGAD sensors can provide the needed time resolution in the presence of the expected large radiation doses. After its adoption by ATLAS, IFAE is now working on the corresponding ASIC design and has developed the hybridization process for the HGTD.

    HL-LHC
    A visual example of pile-up in the ATLAS tracker Credit: CERN

    High temperature superconductor coated conductors for the Future Circular Collider (FCC-hh)

    A collaboration between CERN and Spanish centers ICMAB, UPC, ALBA and IFAE was established in 2016 to evaluate high temperature superconductor coated conductors (HTS-CC) as candidates for the beam screens of the Future Circular Collider (FCC-hh). To study its properties under mechanical stress, IFAE designed and built a dedicated machine that holds a large sample of powered HTS-CC, applies mechanical stress to it, and measures the distributions of mechanical deformation and current density over its surface. The work was funded by CERN for three years (2016-19), was very positively reviewed, and has been recently extended to build a proof-of-concept FCC-hh beam screen device based on HTS-CC.

    FCC
    A schematic map showing where the Future Circular Collider tunnel is proposed to be located Credit: CERN
  • Group Members

    Collider Physics Group

    Staff Researcher

    • Martine Bosman

      Martine Bosman

    • Pilar Casado

      Pilar Casado

    • Jose Crespo

      Jose Crespo

    • Sebastián Grinstein

      Sebastián Grinstein

    • Aurelio Juste

      Aurelio Juste

    • Ilya Korolkov

      Ilya Korolkov

    • Mario Martínez

      Mario Martínez

    • Lluïsa Mir

      Lluïsa Mir

    • Andreu Pacheco

      Andreu Pacheco

    • Imma Riu

      Imma Riu

    Postdoc Researcher

    • Merve Nazlim Agaras

      Merve Nazlim Agaras

    • Lucía Castillo

      Lucía Castillo

    • Pablo Fernández

      Pablo Fernández

    • Javier Jiménez

      Javier Jiménez

    • Judita Mamužić

      Judita Mamužić

    • Javier Montejo

      Javier Montejo

    • Nicola Orlando

      Nicola Orlando

    • Stefano Terzo

      Stefano Terzo

    Research Engineer

    • Raimon Casanova

      Raimon Casanova

    PhD Student

    • Adrià Berrocal

      Adrià Berrocal

    • Juan Carlotto

      Juan Carlotto

    • Gabriel Correa

      Gabriel Correa

    • Yujing Gan

      Yujing Gan

    • Viveka Gautam

      Viveka Gautam

    • Jack Harrison

      Jack Harrison

    • Stergios Kazakos

      Stergios Kazakos

    • Paula Martínez

      Paula Martínez

    • Joaquim Piñol

      Joaquim Piñol

    • Adriá Salvador

      Adriá Salvador

    • Epari Shalini

      Epari Shalini

    • Anil Sonay

      Anil Sonay

  • International Collaborations

    Collider Physics Group

    ATLAS Detector

    ATLAS

    ATLAS at the LHC

    ATLAS is one of the four major experiments at the Large Hadron Collider (LHC) at CERN. It is a general-purpose particle physics experiment designed to exploit the full discovery potential and the huge range of physics opportunities that the LHC provides.

      CERN, Geneva, Switzerland
  • Publications

    Collider Physics Group

  • Instrumentation Projects

    Collider Physics Group

    ITk modules

    3D Pixels

    3D silicon pixel sensors  (ATLAS)

    IFAE in collaboration with CNM led the development of the ultra-radiation-hard 3D silicon pixel sensors for ATLAS. IFAE provided 3D sensors for the innermost pixel layer (IBL) and constructed the first stations for the ATLAS Forward Protons (AFP) tracking system.

    HL-LHC

    HGTD

    High Granularity Timing Detector  (ATLAS)

    IFAE has been deeply involved in the R&D effort to design and fabricate a timing detector to mitigate the effect of pile-up at the HL-LHC. IFAE proposed and demonstarted the Low Gain Avalanche Detector (LGAD) technology developed at CNM to be used in a HGTD detector.

    FCC

    HTS-CC

    High temperature superconductor coated conductors

    A collaboration between CERN and Spanish centers ICMAB, UPC, ALBA and IFAE was established in 2016 to evaluate high temperature superconductor coated conductors (HTS-CC) as candidates for the beam screens of the Future Circular Collider (FCC-hh).

  • Group News

    IFAE organization

    New positions in the IFAE Organization

    January 16, 2023

    Mario Martinez, ICREA professor at IFAE and head of the Gravitational Waves Group, is the new Director of the Experimental Division and takes on the role of IFAE Deputy Director. Martine Bosman, retiring Director of the Experimental Division, assumes the status of IFAE Emeritus.

    New Publication

    New ATLAS group paper

    January 12, 2023

    The paper “Search for a new scalar resonance in flavour-changing neutral-current top-quark decays 𝒕 → 𝒒𝑿 (𝒒 = 𝒖, 𝒄), with 𝑿 → 𝒃𝒃bar, in proton-proton collisions at sqrt(s) = 13 TeV with the ATLAS detector” has been submitted to JHEP.

    New Member

    New Member in the ATLAS group

    January 12, 2023

    Javier Montejo Berlingen has joined the ATLAS group at IFAE as tenure-track Ramon y Cajal Researcher.

    New Member

    New Member in the ATLAS group

    January 9, 2023

    Joaquim Piñol has joined the ATLAS group at IFAE as PhD Student.

    New Position

    Aurelio Juste elected Chair of the ATLAS Publication Committee

    October 26, 2022

    At the 103rd Collaboration Board meeting, held on 14 October 2022, Aurelio Juste was elected as the next Deputy Chair of the Publications Committee (PubComm) for one year, starting on 1 March 2023, and becoming the Chair for the following year, starting on 1 March 2024.

    New Position

    Nazlim Agaras and Imma Riu appointed as conveners of ATLAS physics subgroups

    October 5, 2022

    Both positions, which started on October 1st, have a duration of 2 years.