Since I received my Physics degree from the “Universitat de València” in 2009 I have been working on two neutrino telescopes, ANTARES and KM3NeT international collaborations, both in detector development and in analyses on the search of cosmic neutrino sources and the understanding of the origin of the most energetic cosmic rays.

I have got the opportunity to be on multiple research institutes for short and long stays. At IFIC I carried out my MSci and most of my PhD (obtained in 2015), in combination with multiple stays at CPPM (France). For more than 5 years I have got the opportunity to carry out my post-doctoral research at INFN - Sezione di Bari (Italy) before have the opportunity to return to IFIC in 2021.

Currently I benefit of a distinguished researcher CIDEGENT grant from the GVA co-founded by CSIC in the IFIC research centre. There, I work within the VEGA group, providing and coordinating multiple aspects of detector calibration and analyses while carrying out searches of cosmic neutrino sources.

Neutrino telescopes are challenging detectors proposed for the first time by Markov in 1960. Their main objective is to detect the high energy neutrino fluxes expected from the hadronic interactions which would take place during cosmic ray acceleration at their highest energies, with the two main intrinsic advantages of neutrinos as messengers: lack of trajectory deflection due to its neutral electronic charge and negligible absorption by media in between the acceleration regions and us due to their scarce interaction with matter.

For such purpose, they require of large transparent target masses blinded as much as possible from atmospheric muons, which translates into large volumes of abyss waters (e.g. ANTARES or KM3NeT) or deep Antarctic ice (e.g. Amanda or IceCube) monitored with individual photon detectors (photomultipliers) distributed in a volume that ranges from a tenth of a cubic kilometre (first generation detectors) up to the cubic kilometre and larger.

The main neutrino detection is through muons, produced in some charged neutrino interactions with the surroundings of the detector, since muon track range is orders of magnitude larger than any other neutrino interaction, all the later requiring to be mostly contained within the instrumented detector volume. The Cherenkov radiation emitted by these energetic muons in water or ice is detected by the photomultipliers and their track origin inferred, with a better angular resolution in water due to light scattering. Similarly, the origin of the electromagnetic and hadronic shower interactions is reconstructed from their detected light.

They have a very peculiar sky-map view for astrophysical neutrinos, importantly affected by the down-going atmospheric muon fluxes at the lowest energies (GeV-TeV) and by Earth opacity at the largest neutrino energies (above PeV). As a result, they look the Universe mostly through the Earth and, for the most energetic neutrinos, close to the horizon.

Neutrino telescopes can be used also for atmospheric muon and neutrino flux studies, including neutrino oscillations, together dark matter and other exotic searches.

ANTARES is a first generation neutrino telescope, started to be deployed back in 2008 at ~2500 m depth in the Mediterranean Sea, ~40 km at the South of Toulon (France), and dismantled in 2022.

It was the largest one in the Northern Hemisphere for most of its life time and back then achieved the best limits on neutrino sources on the Galactic Plane. Indeed, due to its location in the Northern Hemisphere and its sky-map view, produced combined point source analyses together IceCube, with a significant contribution to the softer spectra models due to its more dense configuration and therefore lower energy threshold.

Among many analyses, it also contributed to the follow up of the most interesting high energy transient phenomena in the last decade: the gravitational wave GW170817 event, and the neutrino IC170922A event detected in coincidence with a state of gamma enhanced emission from TXS 0506+056, both in 2017. It also started to find a significant independent confirmation of the neutrino cosmic flux detected by IceCube.

KM3NeT is the second generation neutrino telescope in the Mediterranean Sea, in construction since 2015, with a two site detector infrastructure: ORCA, a dense configuration close to ANTARES site, designed mainly for neutrino oscillation studies; ARCA, a cubic kilometer detector, mostly for astronomy studies, at ~3400 m depth in the Mediterranean Sea, ~80 km offshore of Capo Passero (Sicily, Italy).

While still in construction phase (ARCA overcame ANTARES in size a bit before its decomisioning), is already producing data used in the first analyses, including follow ups of interesting IceCube neutrino alerts and gravitational waves.

2020 will be the decade of the multimessenger astronomy!