Two-Year Optical Site Characterization for the Pacific Ocean Neutrino Experiment P-ONE in the Cascadia Basin

TL;DR

This study presents a two-year optical characterization of the Cascadia Basin site for the P-ONE neutrino telescope, demonstrating suitable water clarity and background conditions for future deployment.

Contribution

It provides the first long-term optical measurements in the Cascadia Basin, validating the site for neutrino telescope deployment and informing future large-scale experiments.

Findings

Optical attenuation length of about 28 meters at 450 nm

Comparable optical environment to other deep-water neutrino telescopes

Long-term data supports site suitability for P-ONE

Abstract

The STRings for Absorption length in Water (STRAW) are the first in a series of pathfinders for the Pacific Ocean Neutrino Experiment (P-ONE), a future large-scale neutrino telescope in the north-eastern Pacific Ocean. STRAW consists of two 150 m long mooring lines instrumented with optical emitters and detectors. The pathfinder is designed to measure the attenuation length of the water and perform a long-term assessment of the optical background at the future P-ONE site. After two years of continuous operation, measurements from STRAW show an optical attenuation length of about 28 metres at 450 nm. Additionally, the data allow a study of the ambient undersea background. The overall optical environment reported here is comparable to other deep-water neutrino telescopes and qualifies the site for the deployment of P-ONE.