The geological characterization preceding the construction of a large-scale underground structure, such as the Einstein Telescope (ET), is a mandatory step of civil engineering studies. The ET Italian candidate site is located in the Variscan basement of Sardinia because of its geodynamic quietness, very low seismicity and anthropogenic seismic noise. The ET layout is currently projected as an...
In the framework of the Project Einstein Telescope Sos Enattos, we report the preliminary results of the active-source seismic surveys performed by the INGV team in sites P2 (labelled as Onani) and P3 (labelled as Bitti) in July and September 2021. The main goal of these surveys was the reconstruction of the shallow subsurface velocity structure in correspondence of the two drilling sites....
During the last two years, Sos Enattos has been the subject of an extensive seismic characterization campaign with the installation of several permanent and temporary seismic stations. In this presentation, I will give an overview of this long-term characterization campaign highlighting the main results that have been obtained so far, including the very low noise levels that have been measured...
In this talk I present an update of the long term measurement campaign
going on in Sardinia, for the environmental noise characterization of the
ET candidate vertexes. I will mainly focus on the magnetic noise measured
both in surface and underground of the Sos Enattos site, as well as in P2
(Bitti). A comparison of the Schumann resonances behavior in both sites
and a projection of their...
The region surrounding the dismissed mine of Sos Enattos (Sardinia, Italy) is the Italian candidate site for hosting Einstein Telescope (ET), the next-generation gravitational wave (GW) detector. The site that will host ET must fulfill stringent requirements on seismic disturbances, particularly in the bandwidth 1-10 Hz, where the seismic noise is expected to be dominated by sources of...
In this talk we discuss the preparation of two boreholes at the corners, named P2 and P3, of the ET triangle in Sardinia. The boreholes are designed to host broadband seismometers dedicated to a long-term seismic monitoring at about 250m underground. We also report the principal aspects of the geophysical logs of the boreholes and the sensor installation downhole. Finally, we present the...
Introduction: Subsidies in Euregio Meuse-Rhine and future opportunities
In order to find optimal position for the Einstein-Telescope (ET) in the Euregio Meuse-Rhine (EMR), a detailed understanding of the geological and structural conditions, both on the ground and subsurface is crucial. The short term (during excavation) and long-term performance of the ET underground infrastructures are primarily depended on the geological and structural conditions of the ground....
Hydro geophysical Characterization – Active & Passive Seismic
The requirements for the Einstein Telescope challenge geologists to come up with representations of the subsurface as accurate as possible. A state-of-the-art way are digital 3D models of the subsurface. Various measurements and interpretation of geological observations (e.g. geophysical methods, outcrop studies) serve as input for these models. However, one must also consider the inherent...
Passive Seismic with Medium Aperture Arrays in Limburg
Wind turbines emit seismic signals due to the rotation of the blades and the movement of the tower. Seismic signals radiated from wind turbines are known to interfere with operational seismic monitoring of natural and induced seismicity. With regard to the Einstein Telescope and the design of the passive and active vibration isolation systems, the seismic radiation from wind turbines poses a...
The variations in ambient noise levels, subsurface elastic properties and surface deformation can affect the performance of Einstein Telescope (ET) in various ways. Therefore, the present study aims at providing an overview of integrated geophysical and remote sensing approaches in the Belgian side of prospective ET installation region, an advanced and super sensitive Gravitational-wave...
The Einstein Telescope (ET) is an advanced gravitational-wave observatory, currently in the planning stage that allows to further understanding the Universe through the observation of gravitational waves. The border region between the Netherlands, Belgium and Germany (Euregio Meuse-Rhine) is being considered as a possible location to host the third generation gravitational wave observatory due...
The coupling of ground tilt with the longitudinal degree of freedom is
addressed, both in low frequency, below 100 mHz, and the the new frequency
region addressed by ET, namely above 2 Hz.
It is shown, at the present stage of ET design, the need of a strong
interaction with suspension design WPs, in order to recover the site
conditions needed for the planned ET sensitivity.
During the talk I will like to give an overview on the data server that we are using to store and analyze the ET site data, as well as updates and future plans.
Almost ten years after the first seismic measurements at the Sos Enattos mine, the characterization of the seismic noise wavefield at the ET candidate site in Sardinia has progressed considerably. In this talk, I present a summary of the main results from the active and passive seismic surveys conducted thus far. Particular emphasis is put on those parameters which are most relevant to the...
Summary of NN relevant analyses of seismic data from EMR site
Gravitational-wave detectors are very sensitive instruments that suffer from a huge number of noises. If we aim to observe gravitational waves with Earth-based detectors, we need to take care of every source that can prevent that observation.
Seismic noise is a huge problem in the low frequency band and it is tackled with suspensions and active controls. The low frequency band can also be...
In this talk I summarize the principal aspects to be considered for broadband seismometer deployment in boreholes, which are useful sensing devices for a Newtonian Noise subtraction system. I show what we learned from this kind of installations in Sardinia, e.g. costs and technical aspects to be considered. Finally, I point out some considerations about the development of seismometer chains...
Newtonian noise (NN) will be the very last sensitivity wall in GW detectors below 10-30 Hz. A NN cancellation system is already foreseen in Virgo for O4. For cancelling this noise, we need arrays of seismic sensors deployed in an optimal way close to the test masses. However, when the seismic field deviates from homogeneity and isotropy, finding the optimal array becomes very challenging. An...
For ground-based GW detectors, seismic vibration is the dominating source
of noise in low frequency region (0.1 to 10 Hz), limiting both sensitivity
and duty cycle. Thanks to high performant suspension systems, like the
Virgo Superattenuator, the presently operational 2nd generation advanced
GW antennas have extended their detection band down to 10 Hz. The plan for
future 3rd generation...
Characterizing the geological subsurface setting of a stratified aquifer and the structures that guide the flow paths is crucial for the realization of underground infrastructures such as the Einstein Telescope (ET), that is the European third-generation underground interferometric detector of gravitational waves. The triangular setting of this infrastructure (10 km long sides) has vertices...
As a prototype of the Archimedes experiment, a high sensitivity balance has been constructed. This balance can be used as a tiltmeter and nowadays it is installed at the SAR-GRAV laboratory in Sardinia. The laboratory is settled at the Sos-Enattos site (Lula, Nuoro), a former mine located in a region characterized by low seismic noise. The tiltmeter is a beam balance with an interferometric...
The main scientific goal of Archimedes experiment, installed in the SarGrav laboratory in Sardinia (one of the quietest places in Europe and candidate site for the third generation GW detector Einstein Telescope), is to investigate whether and how vacuum fluctuations interact with gravity.
A high sensitive balance will measure the small weight variations of two YBCO superconducting disks...
We present an extended report on the magnetic noise at the SoS Enattos site, using data collected underground (-111 m) from 2020/09/22 to 2021/11/01 for the N-S magnetic component. To track the time evolution of the noise, we use the Band-Limited Root Mean Square (BLRMS) analizing different frequency bands. We show the diurnal and seasonal variability of the first Schumann resonances. The...
The Archimedes experiment aims at measuring the interaction between vacuum fluctuations
and gravity. Archimedes will measure the force exerted by the gravitational field on a Casimir
cavity whose vacuum energy is modulated with a superconductive transition, by using a
balance as a small force detector. If the vacuum energy does interact with gravity, a force
directed upwards acts on...
Geology in the EMR Region and Geological Field Investigations
Hydro geophysical characterization of the E-Test site in the Euregio Maas-Rhine
