Impact of Marine Microseisms on CUORE Detector Performance

The search for rare events in physics, such as dark matter interactions and neutrinoless double beta decay, requires highly sensitive detectors. One such detector is the CUORE experiment, which operates underground in Italy. It uses low-temperature calorimeters that can detect small changes in temperature caused by these rare events. However, these detectors are also affected by Environmental Noise, which can come from various sources, including vibrations from the sea.

#CUORE Experiment Overview

CUORE, which stands for Cryogenic Underground Observatory for Rare Events, is an experiment located at the Gran Sasso National Laboratory in Italy. It consists of 988 tellurium dioxide (TeO2) crystals, organized into 19 towers. These crystals are cooled to very low temperatures, around 10 millikelvins, to minimize noise and improve sensitivity. The goal of CUORE is to search for neutrinoless double beta decay, a process that could provide insights into the nature of neutrinos and matter.

#Importance of Environmental Noise

Environmental noise can negatively impact the accuracy of measurements taken by the CUORE detectors. Such noise can come from a variety of sources, including seismic activity from earthquakes and vibrations generated by marine waves. Understanding how these external factors influence detector performance is crucial for improving the reliability of results from experiments like CUORE.

#Marine Microseisms

Marine microseisms are small vibrations in the ground caused by ocean waves and storms. These vibrations can travel far from their source and may even reach underground facilities like the one housing the CUORE experiment. Though these vibrations are much smaller than those produced by earthquakes, they can still affect sensitive detectors. The relationship between marine microseisms and the noise within CUORE detectors is an area of significant interest for researchers.

#Study Goals

The main goal of this study is to investigate how marine microseisms impact the Low-frequency Noise of CUORE detectors. By examining data from both marine and seismic sources, we can better understand the correlation between sea activity and detector noise. This knowledge can help in developing strategies to manage and reduce the effects of environmental noise on sensitive experiments.

#Methodology

#Data Sources

To conduct this study, we utilize two main sources of data: the Copernicus Marine Environment Monitoring Service (CMEMS), which provides information on marine activity, and Seismometers installed near the CUORE detectors. This dual approach allows for a comprehensive analysis of how vibrations from the sea correspond with fluctuations in the detectors.

#Seismometers

Two types of seismometers were deployed to monitor vibrations at the Gran Sasso National Laboratory. The first set of sensors, named SEISMO1 and SEISMO2, were installed in the CUORE experimental area to focus on local disturbances. Additionally, a more sensitive seismometer, known as GIGS, is located nearby and is part of a broader network to monitor geological activity across Italy. These seismometers help us detect vibrations originating from both seismic and marine sources.

#Marine Data

CMEMS provides vital data on wave height and sea conditions, which can be linked to the vibrations detected by seismometers. The two marine areas we focus on are the Adriatic Sea and Tyrrhenian Sea, which are positioned near the CUORE facility. By monitoring these regions, we can assess how marine activity influences vibrations that reach the detectors.

#Noise in Cryogenic Detectors

Cryogenic detectors are very sensitive to various forms of noise, including thermal and electronic noise. At extremely low temperatures, thermal noise is minimized, allowing detectors to operate effectively. However, environmental factors like vibrations can introduce new sources of noise, making it essential to understand and manage them.

#Types of Noise

Noise can come from several sources:

1. Electronic Noise: This type comes from the electronics used to read the signals from detectors. Fluctuations in electronic components can introduce unwanted noise.

2. Vibrational Noise: Mechanical vibrations from various sources, such as human activity, can disturb the sensitive elements of the detectors. This can lead to spurious signals that mimic genuine events.

3. Seismic Noise: Vibrations resulting from seismic events, including both small tremors and large earthquakes, can significantly disrupt detector operations.

4. Marine Microseismic Noise: This noise is caused by ocean waves and storms, and can be a key factor in the performance of detectors like CUORE.

#Case Study: CUORE Detectors and Noise Patterns

In this study, we analyze the noise patterns of CUORE detectors concerning marine activity. Our focus is on a specific storm that occurred from September 21 to October 1, 2020. By examining the noise levels during this period, we aim to determine how marine microseisms affected detector performance.

#Noise Analysis

To analyze noise, we take continuous readings from CUORE detectors and apply a series of filters to obtain a clear signal devoid of thermal pulses or other disturbances. This allows us to isolate the noise events that are purely due to external influences, such as marine microseisms.

#Connecting Marine Activity with Detector Noise

By gathering data from both CMEMS and the seismometers, we establish a correlation between marine activity and low-frequency noise within CUORE detectors. The results show that noise levels increase during marine storms, particularly at a frequency of 0.6 Hz, where the detectors are most responsive.

#Statistical Correlation

We utilize linear regression to quantify the relationship between sea activity and the noise recorded by CUORE. The analysis reveals that higher wave activity correlates with increased noise in the detectors. This finding emphasizes the significance of environmental factors in the operation of sensitive instruments.

#Implications for Future Research

Understanding how marine microseisms affect CUORE detectors can lead to better noise management strategies. By mitigating the impact of these environmental factors, we can enhance the sensitivity and resolution of measurements, benefiting future experiments in particle physics and astrophysics.

#Conclusion

This study highlights the importance of considering environmental noise when conducting experiments with sensitive detectors like CUORE. By examining the correlation between marine microseisms and low-frequency noise, we gain valuable insights into how to improve detector performance. As we continue to explore the connections between ocean activity and scientific measurements, we pave the way for advancements in our understanding of fundamental physics.