The Pacific Ocean Neutrino Experiment (2111.13133v1)

Abstract: Neutrino telescopes are unrivaled tools to explore the Universe at its most extreme. The current generation of telescopes has shown that very high energy neutrinos are produced in the cosmos, even with hints of their possible origin, and that these neutrinos can be used to probe our understanding of particle physics at otherwise inaccessible regimes. The fluxes, however, are low, which means newer, larger telescopes are needed. Here we present the Pacific Ocean Neutrino Experiment, a proposal to build a multi-cubic-kilometer neutrino telescope off the coast of Canada. The idea builds on the experience accumulated by previous sea-water missions, and the technical expertise of Ocean Networks Canada that would facilitate deploying such a large infrastructure. The design and physics potential of the first stage and a full-scale P-ONE are discussed.

• The paper reports a novel multi-cubic-kilometer underwater neutrino telescope design that significantly boosts high-energy neutrino detection sensitivity.
• It details a modular, scalable approach using clusters of optical sensors and prior lessons from seawater observatories to refine data accuracy.
• The study underscores P-ONE’s role in multi-messenger astronomy by improving global sky coverage and real-time response for cosmic event follow-up.

The Pacific Ocean Neutrino Experiment (P-ONE): Advancing Neutrino Astronomy

The Pacific Ocean Neutrino Experiment (P-ONE) is an ambitious project proposed to enhance our understanding of high-energy neutrinos through constructing a multi-cubic-kilometer neutrino telescope off the coast of Vancouver Island, Canada. This endeavor aims to extend the reach of neutrino observation in an hitherto unexplored region of the sky, thereby supplementing the capabilities of existing terrestrial observatories such as IceCube and future planned detectors like KM3NeT and Baikal-GVD.

Scientific Rationale and Goals

Neutrinos are established as powerful probes of cosmic phenomena due to their weakly interacting nature, which allows them to traverse vast cosmic distances unimpeded and carry valuable information about extreme astrophysical environments. The discovery of a diffuse astrophysical neutrino flux by IceCube has already highlighted the potential of neutrinos in studying high-energy processes far beyond our galaxy. Despite existing achievements, the low flux of high-energy neutrinos limits the statistical power available for such studies.

P-ONE aims to overcome these limitations through a significantly larger volume detector, enabling greater sensitivity and accuracy in neutrino detection. The key scientific goals include identifying novel astrophysical neutrino sources, probing particle physics at energy scales inaccessible to terrestrial accelerators, and providing essential data for multi-messenger astronomy, which involves coordinated observations with other cosmic messengers such as gravitational waves and gamma rays.

Technical Design and Implementation

P-ONE leverages the experience garnered from previous sea-water-based neutrino observatories and the technical infrastructure of Ocean Networks Canada (ONC). The observatory is envisioned to consist of seven clusters, each with multiple mooring lines equipped with various optical sensors designed for high-precision neutrino detection. This modular and scalable design allows for a phased development, beginning with initial pathfinder experiments, STRAW and STRAW-b, which have been deployed to ascertain the site's optical properties and environmental conditions.

The optical and calibration modules included in the P-ONE design are tailored for excellent directional and energy resolution, focusing on horizontal event tracks where the detection potential is maximal. Initial studies report an attenuation length at different wavelengths that are promising for the feasibility of P-ONE's detection strategy, albeit with challenges such as bioluminescence and $^{40}K$ background emissions that need to be addressed.

Role and Future of P-ONE in Neutrino Astronomy

P-ONE is conceived as an integral part of a global network of neutrino telescopes, coordinated under the PLE$\nu$M (Planetary Neutrino Monitoring system), a distributed monitoring initiative that seeks to provide comprehensive sky coverage and enhance the detection capabilities of neutrino observatories worldwide. This network aims to synergistically boost the discovery potential for neutrino sources across both hemispheres and improve the real-time response capabilities crucial for multi-messenger event follow-up.

In conclusion, the P-ONE project represents a significant step forward in enhancing the sensitivity and coverage of neutrino observatories, fostering contributions to fundamental physics, astrophysical source identification, and multi-messenger connections. Through collaboration and technological innovation, P-ONE holds the potential to considerably advance the frontier of neutrino science. Future developments will focus on aligning P-ONE's progress with internal milestones while integrating with the broader strategic objectives of the global high-energy astrophysics community.