In Advanced Virgo ten super attenuators under vacuum isolate the mirrors from seismic noise. Each tower is equipped with more than 20 stepper motors used to change the DC position of the suspension filters and their sensors. An additional set of motors is required to move the mirrors used by the Thermal Compensation System (TCS). A software application to control the motors, check their...
Brownian coating thermal noise is a limiting noise in advanced GW detectors at mid-range frequency and it is due to structural dissipation inside the material. The measurement of the coating loss angle requires substrates to be stable with respect to their dissipative behaviour. Particularly, silica discs are subject to ageing, compromising the accuracy of mechanical characterizations. It has...
Recent discoveries of binary black holes by gravitational-wave detection hint at the opportunity of observing binaries containing neutron stars. Unlike with black holes alone, the presence of a neutron star can help us constrain the equation of state (EOS) of ultradense matter. The feasibility of constraining the equation of state through gravitational-wave detections have typically been...
Atom interferometers employing optical cavities to enhance the beam splitter pulses promise significant advances in science and technology, notably for future gravitational wave detectors. Long cavities, on the scale of hundreds of meters, have been proposed in experiments aiming to observe gravitational waves with frequencies below 1 Hz, where laser interferometers, such as LIGO, have poor...
The computational effort required by real-time detection of gravitational waves is very large because tens of thousands of templates need to be processed in real time. Graphics processing unit(GPU) plays an important role in gravitational wave detection, depending on its highly parallel design and convenient general propose programming. The SPIIR detection pipeline is fully optimized and...
Absorbing baffles and irises are used to suppress stray light in the arm pipes of long baseline optical interferometric detectors of gravitational waves like LIGO and Virgo, due to the finite size of the mirrors etc.
Baffle themselves, however, can be sources of diffracted light, and hence noise.
Here we analyze diffraction from baffles using a uniform version of the geometrical thery of...
Observations of gravitational-waves (GW) from binary black holes coalescence provide us with the opportunity of testing General Relativity (GR) in the strong field regime. Evidence for non-GR physics can be investigated via comparing the incoming GW signal to phenomenological GR waveform models including parametrised deviations from GR, or non-GR parameters. However, the underlying GR model...
The current GW template bank for BNS search is using the aligned-spin waveform without considering the tidal effects. The deformation of the NS could become significant in the late inspiral stage. The diverges of GW waveform between the non-tidal and tidal could make the signal-to-noise ratio for BNS search decrease. We have explored to build a BNS template bank including the tidal parameters...
The Regione Sardinia has established the funding of a realization of a pilot underground Laboratory in the Sos-Enattos mine, in the LULA municipality. This site has been received attention since last decade for its extremely low level of seismic noise as possible candidate for hosting the third generation gravitational wave interferometers, particularly ET. The project of the laboratory will...
We present results of a search of periodic interferences in O1 data. The code searches for periodicities in narrowband time domain segments that are analysed by Time Domain F-statistic pipeline. Accuracy of the parameter estimation by the code is simulated. The frequencies of the periodic interferences are compared with data set of instrumental environmental lines found by other software. Some...
We present the status of aluminum-gallium-arsenide (AlGaAs) as a coating material for the test masses of future interferometric gravitational wave detectors. We discuss the thermal noise advantages of using AlGaAs, the status of its optical properties such as scatter and absorption, as well the challenges with the size availability. Different options to solve the size problem are presented.
The Advanced Virgo thermal compensation system (TCS), composed by wavefront sensors and actuators, has been conceived to correct mirror imperfections and to mitigate the thermal gradient inside the optics ensuring the detector optimal configuration.
Thermal compensation system components have been individually tested and characterized ensuring their operation within Advanced Virgo noise...
Gravitational waves from core-collapse supernovae are produced by the excitation of different oscillation modes in the proto-neutron star (PNS) and its surroundings, including the shock. In this work we study the relationship between the post-bounce oscillation spectrum of the PNS-shock system and the characteristic frequencies observed in gravitational-wave signals from core-collapse...
