Seismic noise study in the underground Baksan Neutrino Observatory

TL;DR

This study characterizes seismic noise at the underground Baksan Neutrino Observatory, highlighting dominant oceanic microseisms and comparing measured noise levels to established models, with implications for gravitational wave detection.

Contribution

It provides the first detailed seismic noise profile of the Baksan Neutrino Observatory and assesses the Newtonian noise limit using measured data and Saulson's model.

Findings

Seismic noise below 1 Hz is dominated by oceanic microseisms.

Measured noise levels approach Peterson's low noise model at higher frequencies.

The Newtonian noise limit at the site is evaluated based on measurements.

Abstract

In this paper we report a study of the seismic noise measured in the underground Baksan Neutrino Observatory. The main spectral feature below 1 $Hz$ is the oceanic microseism, while for greater frequencies the measured horizontal and vertical accelerations approaches the Peterson low noise model. Using two synchronized seismometers we also studied the coherence in the microseismic band ($0.1-0.5Hz$) between three underground stations located at $0.3km$, $1.4km$ and $3.7km$ from the tunnel entrance. Finally, on the base of our measurements we evaluate the Newtonian noise limit at this site using the Saulson's model.