C. Di Fronzo
A5050781110- Pulsars and Gravitational Waves Research
- Gamma-ray bursts and supernovae
- Astrophysical Phenomena and Observations
- Geophysics and Sensor Technology
- Geophysics and Gravity Measurements
- High-pressure geophysics and materials
- Cosmology and Gravitation Theories
- Seismic Waves and Analysis
- Atomic and Subatomic Physics Research
- Mechanical and Optical Resonators
- Astrophysics and Cosmic Phenomena
- Dark Matter and Cosmic Phenomena
- Cold Atom Physics and Bose-Einstein Condensates
- Radio Astronomy Observations and Technology
- Advanced Frequency and Time Standards
- Seismology and Earthquake Studies
- Superconducting and THz Device Technology
- Superconducting Materials and Applications
- Mechanics and Biomechanics Studies
- 3D Modeling in Geospatial Applications
- Adaptive optics and wavefront sensing
- Astronomical Observations and Instrumentation
- Advanced Measurement and Metrology Techniques
- earthquake and tectonic studies
- 3D Surveying and Cultural Heritage
University of Birmingham
2019-2024
Université Libre de Bruxelles
2023-2024
University of Liège
2023
National Institute for Subatomic Physics
2022
University of Glasgow
2022
Vrije Universiteit Amsterdam
2022
The Laser Interferometer Gravitational Wave Observatory (LIGO) has been directly detecting gravitational waves from compact binary mergers since 2015. We report on the first use of squeezed vacuum states in direct measurement with Advanced LIGO H1 and L1 detectors. This achievement is culmination decades research to implement gravitational-wave During ongoing O3 observation run, are improving sensitivity interferometers signals above 50 Hz by up 3 dB, thereby increasing expected detection...
On April 1st, 2019, the Advanced Laser Interferometer Gravitational-Wave Observatory (aLIGO), joined by Virgo detector, began third observing run, a year-long dedicated search for gravitational radiation. The LIGO detectors have achieved higher duty cycle and greater sensitivity to waves than ever before, with Hanford achieving angle-averaged binary neutron star coalescences distance of 111 Mpc, Livingston 134 Mpc factors 74.6% 77.0% respectively. improvement in stability is result several...
The characterization of the Advanced LIGO detectors in second and third observing runs has increased sensitivity instruments, allowing for a higher number detectable gravitational-wave signals, provided confirmation all observed events. In this work, we present methods used to characterize curate publicly available datasets, including strain data quality products. We describe essential role these datasets LIGO-Virgo Collaboration analyses gravitational-waves from both transient persistent...
The motion of a mechanical object, even human-sized should be governed by the rules quantum mechanics. Coaxing them into state is, however, difficult because thermal environment masks any signature object's motion. also effects proposed modifications mechanics at large mass scales. We prepared center-of-mass 10-kilogram oscillator in with an average phonon occupation 10.8. reduction temperature, from room temperature to 77 nanokelvin, is commensurate 11 orders-of-magnitude suppression...
Gravitational Wave interferometers achieve their profound sensitivity by combining a Michelson interferometer with optical cavities, suspended masses, and now, squeezed quantum states of light. These modify the measurement process LIGO, VIRGO GEO600 to reduce noise that masks astrophysical signals; thus, improvements squeezing are essential further expand our gravitational view universe. Further reducing will require both lowering decoherence from losses as well more sophisticated...
Abstract The differential seismic motion between the Internal Seismic Isolation platforms on Advanced Laser Interferometer Gravitational Wave Observatory, affects sensitivity of detector at lower frequencies (below 1 Hz), because each platform moves independently. This induces noise inside cavities auxiliary optics placed platforms, which translates into a higher control effort to maintain stability and resonance. paper shows that can be efficiently measured by Capacitive Position Sensors...
Noise due to scattered light has been a frequent disturbance in the Advanced LIGO gravitational wave detectors, hindering detection of waves. The non stationary scatter noise caused by low frequency motion can be recognized as arches time-frequency plane channel. In this paper, we characterize scattering for LIGO's third observing run O3 from April, 2019 March, 2020. We find at least two different populations and investigate multiple origins one them well its mitigation. that relative...
We present the design, control system, and noise analysis of a 6-axis seismometer comprising mass suspended by single fused silica fiber. utilize custom-made, compact Michelson interferometers for readout motion relative to table successfully overcome sensitivity existing commercial seismometers over an order magnitude in angular degrees freedom. develop sensor gravitational-wave observatories, such as LIGO, Virgo, KAGRA, help them observe intermediate-mass black holes, increase their duty...
Abstract To achieve the expected level of sensitivity third-generation gravitational-wave (GW) observatories, more accurate and sensitive instruments than those second generation must be used to reduce all sources noises. Amongst them, one most relevant is seismic noise, which will require development a better isolation system, especially at low frequencies (below 10 Hz), operation large cryogenic silicon mirrors, improvement optical wavelength readouts. In this framework, article presents...
Teleseismic, or distant, earthquakes regularly disrupt the operation of ground--based gravitational wave detectors such as Advanced LIGO. Here, we present \emph{EQ mode}, a new global control scheme, consisting an automated sequence optimized filters that reduces and coordinates motion seismic isolation platforms during earthquakes. This, in turn, suppresses differential interferometer arms with respect to one another, resulting reduction DARM signal at frequencies below 100\,mHz. Our method...
We demonstrate the control scheme of an active platform with a six degree freedom (6D) seismometer. The inertial sensor simultaneously measures translational and tilt degrees does not require any additional sensors for stabilization. show that feedforward cancelation can efficiently decouple tilt-to-horizontal coupling seismometer in digital scheme. stabilize frequency band from 250 mHz up to 10 Hz (X, Y) achieve suppression factor 100 around 1 Hz. Further ground vibrations was limited by...
Abstract Earth-based gravitational waves interferometric detectors are shot-noise limited in the high-frequency region of their sensitivity band. While enhancing laser input power is natural solution to improve on shot noise limit, higher also increases optical aberration budget due absorption highly reflective coatings mirrors, resulting a drop detector. Advanced Virgo exploits Hartmann Wavefront Sensors (HWSs) locally measure absorption-induced aberrations by monitoring path length change...
The sensitivity of the Advanced LIGO detectors to gravitational waves can be affected by environmental disturbances external themselves. Since transition from former initial phase, many improvements have been made equipment and techniques used investigate these effects. These methods aided in tracking down mitigating noise sources throughout first three observing runs advanced detector era, keeping ambient contribution below background levels detectors. In this paper we describe how they led...
Compact Michelson interferometers are well positioned to replace existing displacement sensors in the readout of seismometers and suspension systems, such as those used contemporary gravitational-wave detectors. Here, we continue our previous investigation a customised compact sensor built by SmarAct that operates on principle deep frequency modulation. The focus this paper is linearity device its subsequent impact sensitivity. We show three primary sources nonlinearity arise sensor:...
Advanced LIGO and Virgo have detected gravitational waves from astronomical sources to open a new window on the Universe. To explore this realm requires an exquisite level of detector sensitivity, meaning that much stronger signal instrumental environmental noise must be rejected. Selected examples unwanted in are presented. The initial focus is how existence (characterized by particular frequencies or time intervals) was discovered. Then, variety methods used track down source noise, e.g.,...
High-quality optical resonant cavities require low loss, typically on the scale of parts per million. However, unintended micron-scale contaminants resonator mirrors that absorb light circulating in cavity can deform surface thermoelastically and thus increase losses by scattering out mode. The point absorber effect is a limiting factor some high-power experiments, for example, Advanced LIGO gravitational-wave detector. In this Letter, we present general approach to from first principles...
We demonstrate the control scheme of an active platform with a six degree freedom (6D) seismometer. The inertial sensor simultaneously measures translational and tilt degrees does not require any additional sensors for stabilisation. show that feedforward cancellation can efficiently decouple tilt-to-horizontal coupling seismometer in digital scheme. stabilise frequency band from 250 mHz up to 10 Hz horizontal achieve suppression factor 100 around 1 Hz. Further ground vibrations was limited...
Compact Michelson interferometers are well positioned to replace existing displacement sensors in the readout of seismometers and suspension systems, such as those used contemporary gravitational-wave detectors. Here, we continue our previous investigation a customised compact sensor built by SmarAct, which operated on principle deep frequency modulation. The focus this paper is linearity device. We show three primary sources nonlinearity that arise -- residual ellipticity, intrinsic...
We present the design, control system, and noise analysis of a 6-axis seismometer comprising mass suspended by single fused silica fibre. utilise custom-made, compact Michelson interferometers for readout motion relative to table successfully overcome sensitivity existing commercial seismometers over an order magnitude in angular degrees freedom. develop sensor gravitational-wave observatories, such as LIGO, Virgo, KAGRA, help them observe intermediate-mass black holes, increase their duty...
Abstract Laser frequency stabilization is a crucial technique for precision metrology. We demonstrate laser control using compact, interferometric sensor, specially modified sensitivity to noise. This setup achieves balance between compact size, ease of use, and affordability. stabilize the noise, low-cost solid-state laser, 4.5 <?CDATA ${\mathrm{kHz}}\ \sqrt{\mathrm{Hz}}^{-1}$?> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:mi...