The event rate of current observatories is partially limited by noise arising from temperature-driven position fluctuations of the test mass mirror surfaces used for probing space time dynamics.
Future gravitational-wave observatories address this limitation by using cryogenically cooled test masses;
current approaches for continuously removing heat (resulting from absorbed laser light) rely...
Nowadays, sensors' resolution limits their performance at low frequency which reduces their operating range. Sensors with a good resolution at low frequency are required to improve the performance of gravitational wave detectors in the sub-Hz frequency range. We are currently developing an inertial sensor with a sufficient resolution at low frequency from 10 mHz to 100 Hz. We are focusing on...
Ground based gravitational wave detectors are limited at low frequencies by seismic noise and other related technical noise sources.
In order to overcome these limitations, we study the use of interferometry based, local displacement sensors as part of the active seismic noise mitigation at the pendulum-suspensions of these detectors.
Our idea is to use so called “Deep-Frequency-modulated”...
The Laser Interferometer Space Antenna (LISA) will be the first space-based gravitational wave observatory. LISA is a high precision interferometer in space with an arm length of 2.5 million km. The optical benches are made by bonding silicate glass components to an ultra-low-expansion glass ceramic which does not allow rearrangements of the optical components. Since the development,...
Thermal noise of the test masses is one of the limiting noise sources in Advanced detectors. It is expected to remain a limiting noise source in future detectors, despite radical changes to the design including cryogenic operations, new materials and the use of longer laser wavelengths. We will discuss progress towards verifying higher-order Hermite-Gauss laser modes as possible alternative or...
GW170817 opened a new era of the observation of the Universe through the multi-messenger astronomy. The full exploitation of this new era will pass through the realisation of innovative tools, possibly compliant with the FAIR principles, allowing the efficient exchange of essential information between the different partners in a multi-messenger observation. Present and future gravitational...
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...
Massive halo compact astrophysical objects (MACHOs) are a potential candidate of dark matter, the presence of which in the interstellar medium can cause deflection of gravitational waves (GWs), a phenomenon called gravitational lensing. If we do not find any lensing signature in the LIGO-Virgo data of gravitational waves, we can put an upper cut-off on their abundance in the mass range of...
Improving the sensitivity of existing and future ground-based gravitational-wave detectors will enable us to detect more astronomical sources with higher precision. As the gravitational-wave signals are strong and present for a longer time in the low-frequency regime, it would be beneficial to extend the current sensitivities to lower frequencies (< 10Hz). However, seismic noise coupling into...
There is a funded proposal, and ability to retrofit (as in not part of the Ligo A+ baseline) HoQI Interferometers in the big beamsplitter suspension. While the theoretical design and components had been finalized, no mechanical design was made that would fit the set envelope. This poster will display the first iteration towards a mechanical design that could be installed to allow for local...
The Laboratory of Space Systems and Optomechanics (LASSO) at Texas A&M University is working to create novel, highly sensitive inertial sensors by combining our fused-silica optomechanical resonators with compact, high-precision interferometers. Our resonators have high mechanical quality factors and low thermal acceleration noise. Q’s of 2.45 x 10^5 were previously achieved at mTorr...
TOBA (TOrsion-Bar Antenna) is a ground-based gravitational wave detector using a torsion pendulum. The resonant frequency of torsional motion is ~1 mHz, therefore TOBA has good design sensitivity of $10^{-19}$ /√Hz at 0.1 Hz in low frequencies (0.1 Hz – 10 Hz). TOBA can detect intermediate mass black hole binary mergers and so on. A prototype detector Phase-III TOBA with a 35 cm-scale pendulum...
To detect gravitational waves at frequencies below 30Hz the low-frequency sensitivity of the current observatories must be improved and, in the case of LIGO, this is caused by control noise from a mixture of sources. To facilitate this improvement in sensitivity, new seismic and suspension sensors are required. This poster outlines the development of these new sensors that can be applied to...
Tilt coupling is one of the limiting factors for the low-frequency sensitivity of gravitational-wave detectors. Implementing inertial seismic isolation of the suspension platform in all 6 DoF makes it quiet in all degrees of freedom simultaneously and minimises coupling of all DoF to interferometer length. In this poster, we discuss the potential improvement in the sensitivity of GW detectors...
A dual-pass differential Fabry–Perot interferometer (DPDFPI) is one candidate of the interferometer configurations utilized in future Fabry–Perot type space gravitational wave antennas, such as Deci-hertz Interferometer Gravitational wave Observatory (DECIGO) and B-DECIGO. In this poster, the working principle of the DPDFPI has been investigated and necessity to adjust the absolute length of...
Gravitational-wave interferometric detectors have many internal seismic platforms to support the various suspended optics. For future detectors, the relative motion of these seismic platforms, via coupling to the auxiliary length controls of the suspended optics, are predicted to be the limiting noise source at low frequencies below 1 Hz. By measuring, then stabilizing the relative motion...
Multi-fringe capable, compact laser interferomters are studied as sensors for displacement sensing of suspended test masses and inertial sensors in future ground-based detectors to improve their low-frequency noise. We are investigating such a sensor, or optical head, design that uses a quasi-monolithic component and deep-frequency modulation interferometry to enable sub-picometer level...
The Einstein Telescope will have Michelson interferometers with Fabry-Perot cavities in the two arms. They will need the widest possible stored beams to reduce thermal noise, using mirror test masses with diameter at the limit of technical feasibility. Recombining those wide beams into the beam splitter would be challenging in any case. Unlike other detectors, the Einstein Telescope will...
The Glasgow Cryogenic Interferometer Facility will be a double cavity cryogenic interferometer prototype with suspended silicon optics which will allow the testing of future technologies required for 3rd generation detectors. This poster discusses the modelling of one of the room temperature steering suspensions which will be used at this facility.
There are many astrophysical scenarios where extreme mass ratio inspiral (EMRI) binaries can be surrounded by matter (esp. dark matter) distribution. The mass distribution can affect the dynamical properties (e.g. orbital frequency, orbital velocity, etc.) and the rate of energy radiation from the EMRI. We assume a power law dependency of mass distribution density on the radial distance from...
LIGO and Virgo have detected more than 70 signals from black hole and/or neutron star mergers. All measured signals come in-band at around 30 Hz as suspension control noise, fueled by many cross couplings between angular and translational degrees of freedom, is dominant below 30 Hz. It is impossible to know, but exciting to imagine what signals are lurking there once we can access this...
Cosmic Explorer (CE) is the US concept for a next-generation ground-based gravitational-wave observatory. CE will have the ability to determine the nature of the densest matter in the universe, reveal binary black hole (BH) populations throughout cosmic time, probe the history of the expanding universe, and explore Einstein’s relativity with unprecedented precision. Sources that are barely...
Ground-based interferometric gravitational wave detectors at LIGO are complex instruments that need to be in light resonance or 'locked' in order to take data and make astronomical observations. The 'lock' is maintained by a series of control loops which can be disturbed by systematic or environmental factors. Multiple detectors need to be simultaneously in lock to triangulate the sky location...
