The Dark Energy Survey (DES) collaboration created in 2021 the largest ever maps of the distribution and shapes of galaxies. These maps trace both ordinary and dark matter in the universe out to a distance of more than 7 billion light years. The analysis, which includes the first three years of data from the survey, is consistent with predictions from the standard cosmological model. Nevertheless, there remain hints from DES and other experiments that matter in the current universe is a few percent less clumpy than predicted.

After a successful commissioning during 2020, the Dark Energy Spectroscopic Instrument (DESI) finished the phase of Survey Validation in May 2021, and started the main survey observations. After a few months of observations DESI was already the largest spectroscopic survey ever, with more than 10 million galaxy redshifts obtained. During the next 5 years, DESI will build the largest 3D map of the distribution of galaxies in the universe. This will allow us to unravel the mysteries of dark energy, the repulsive force that drives the accelerated expansion of the universe.

As part of the upgrade program, Virgo installed in 2021 a new instrumented baffle with photosensors surrounding the end mirror of the Input Mode Cleaner at EGO. This culminates more than two years of work at IFAE for the design and construction of a novel and innovative device to control and monitor the stray light inside the experiment, a persistent source of noise at interferometers.

Researchers from the MAGIC collaboration detected in 2021 very high-energy gamma rays from Rs-Ophiuchim a recurrent nova in the Milky Way. This event is the first one detected at these energies and allows a better understanding of these class of eruptions and their potential role in the production of the mysterious cosmic rays that inhabit the Milky Way. The detection of very high energy photons from RS-Ophiuchi by the MAGIC telescopes identifies novae as a new type of very high-energy gamma-ray source and reveals proton acceleration in thermonuclear nova explosions.

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 plays a leading role in the High- Granularity Timing Detector (HGTD) activities, leading the sensor, module assembly and test-beam groups, and with a member of IFAE acting as the sub-Project Leader. IFAE is also playing a critical role in the digital design of the final HGTD readout chip. The first full size prototype chip was fabricated in 2021 and IFAE was the first institute to bump-bond the chip to LGAD sensors.

In 2021 the ATLAS Collaboration reported a possible weak hint for a light charged Higgs boson produced from top quark decays and that couples to a charm and a strange quark. The data presents a 3 standard deviations excess compared to the Standard Model (SM) background predictions. This possible signal is elusive and suffers from a large amount of SM background. For this reason, a sophisticated data analysis strategy involving substantial use of machine learning techniques was deployed. The IFAE-ATLAS team has not only contributed to this result, but is also completing a search for this process in a complementary channel featuring only one lepton or two opposite-charge leptons.

In 2021 the European Strategy Forum on Research Infrastructures (ESFRI) decided to include the Einstein Telescope (ET) in the 2021 update of its roadmap. This confirms the relevance of this major international project for a next generation gravitational waves observatory for the future of research infrastructures in Europe and gravitational wave research at global level.

IFAE’s spin-off Deep Detection SL was founded in July 2020 and its main domain of activities is X-ray detectors for industrial quality control and security. In 2021 Deep Detection achieved a one million euros pre-seed investment round deepdetection.tech mainly contributed by two venture capital companies. The company ended the year with 5 full-time workers. Deep Detection is preparing to launch its first product, PhotonAI, an X-ray camera with deep learning capabilities. The backbone of the technolog is the know-how obtained by IFAE from having invented and developed novel instruments to explore fundamental science and address technological challenges.

IFAE spin-off Qilimanjaro Quantum Tech secured in 2021 nearly one million euros in grants from the CDTI and the Misiones program. On top of this funding the turnover of the first customers of Qilimanjaro in 2021 was another million euros, a growth of 100% compared to 2020. In 2021 Qilimanjaro was selected in the 5 top Quantum Computing Startups to watch in 2022 by StarUS Insights.

In June 2021 PIC upgraded its network connectivity by a factor of ten, up to 200 Gbps. This was a major infrastructure milestone towards the preparation of increased data volumes in the upcoming LHC run, and in virtually every experiment PIC collaborates with. The new improved connectivity was enabled by the deployment of a new dark fiber ring by the National and Regional academic network providers RedIRIS and Anella Científica. This new network infrastructure connects important Research Infrastructures in the Vallès area such as PIC, the ALBA Synchrotron and the UAB to the new national 100Gbps infrastructure RedIRIS-NOVA100.

During 2021 the BRL, installed in the CTA-North site, was operated on a monthly basis, on days around the full moon. IFAE participated in these on-site data taking shifts and in the analysis of the BRL data. The possibility of performing remote and semi-remote observations with the BLR, with minimal intervention of on-site personnel, was successfully tested.