IGFAE

Since 2008, IGFAE researchers have been working on the upgrade of the CERN LHCb experiment’s vertex subdetector and highest level trigger (HLT). The development of the new VELO was completed in May 2022 with the second half of the detector in the accelerator cavern. The sensors, ASIC (Application-Specific Integrated Circuit), electronics, vacuum and cooling system were developed at the Institute. VELO is an instrument that will help to discover why there is more matter than antimatter in the universe in the current operating period (Run3) of the LHC, which began operations in June 2022.

The Pierre Auger Observatory, situated just outside Malargüe, in the province of Mendoza (Argentina), is home to the world’s largest and most accurate ultra-high energy cosmic ray detector (UHECR). The IGFAE has been involved in the construction and operation of this Observatory since its inception in 2002, spearheading Spanish participation.

In 2022, the IGFAE made a major contribution to the article describing the results of phase 1 of the data collection (between 2008 and 2020) at the Pierre Auger Observatory in order to determine the arrival directions of ultra-high energy cosmic rays (Arrival Directions of Cosmic Rays above 32 EeV from Phase One of the Pierre Auger Observatory. A. Aab et al. – The Pierre Auger Collaboration – Astrophysical Journal 935 (2022) 170. DOI: 10.3847/1538-4357/ac7d4e). Also in 2022, and as a direct result of this initiative, the IGFAE was directly involved in drawing up the catalogue of the 100 most energetic cosmic ray events detected at the Pierre Auger Observatory, a clear illustration of the quality of the data collected at the Observatory.

DUNE (Deep Underground Neutrino Experiment) is the international collaboration for the development of one of the most sophisticated neutrino experiments ever built in the world. In 2022, the IGFAE worked on the future US neutrino detector. Its activities were focused mainly on the siting of DUNE’s Near Detector (ND) as part of the ND-GAr (Gaseous Argon) system.

IGFAE is also exploring the possibility of implementing for the first-time the detection of primary scintillation (‘T0’) in a gaseous Time-Projection-Chamber detector operated in a neutrino beam. The emergence of this new technological direction, pioneered by the IGFAE, has two aspects: on one hand, the availability of ultra-intense neutrino beams (such as those coming from the Fermilab accelerator in the USA) that enable operation in the gas phase, and on the other hand, the significant progress madein the development of silicon-based photosensors. All of this linked to advances in the profound understanding of electron transport and scintillation processes in high-pressure gases, to which the IGFAE has also contributed.

NEXT is an international collaboration made up mainly of institutions based in Spain – the IFIC (Valencia), DIPC (Donosti) and IGFAE (Santiago) and the USA – FermiLab (Chicago, Illinois), University of Texas at Arlington and the University of Harvard (Massachusetts). The main objective is the construction of the NEXT-100 detector in the Canfranc Underground Laboratory (LSC in its Spanish initials) in Spain to search for neutrinoless double beta decay of the xenon 136 nucleus. If this decay were discovered, the neutrino would be shown to be its own antiparticle, a paradigm shift in our understanding of Particle Physics and Cosmology of the Universe.

The IGFAE has participated in the preparation and estimation of the capacity of the NEXT-100 detector. The construction work is almost complete, and it is believed that data collection can commence at the LSC in 2023. This year has also seen the IGFAE NEXT group’s participation in analysing the data from smaller prototypes such as DEMO++, installed at IFIC (Valencia), and NEXT-White located at the LSC, as well as in actions to increase the detection volume of NEXT-100 (NEXT-HD) and its capacity for detecting neutrinoless double beta decay (NEXT-Bold).

The IGFAE is involved in a scientific programme at FAIR – the world’s largest nuclear physics facility (https://fair-center.eu/), currently being constructed in Darmstadt (Germany). This project uses nuclear reactions induced by exotic projectile beams at relativistic energies to characterise the reaction mechanisms and obtain information about the structure and dynamics of nuclear systems far off stability in the R3B experiment. In 2022 R3B conducted intense experimental activity, with the active involvement and participation of the IGFAE team.

IGFAE leds the first experiment of S455 fission induced by a 238U relativistic beam on an LH2 target in the quasielastic regime (p,2pf). The staff of IGFAE also participates in preparing the 2022 R3B measurement campaign (assembly, test runs, software development) to study short-range correlations in exotic nuclear matter. They also contribute to drawing up letters of intent organised by FAIR to define the R3B collaboration strategy for the period 2023-2025. From an instrumental perspective, IGFAE has focused on detectors in the R3B target area and, for more than 10 years, they have been spearheading the construction of CALIFA. Work is currently underway in the CEPA sector.