Mr Jerome Degallaix (Laboratoire des Matériaux Avancés - CNRS)
3/1/18, 11:10 AM
Upgrade from second generation interferometers and third generation ones will require larger size optics as well as new material substrates to handle low temperatures. In parallel to this technological challenges, a worldwide intensive research is underway to lower the coating thermal noise from the mirrors. In this presentation, we will review the technological development and future plans...
Daniel Penkert (AEI Hannover)
3/1/18, 11:40 AM
The space-borne gravitational wave observatory LISA aims to measure sources in the 0.1 mHz to 1 Hz frequency range. Core to this measurement is the optical readout of differential path lengths between free-floating test masses aboard three satellites orbiting the sun in a tilted cartwheel formation. On average, the satellites’ positions form an equilateral triangle of 2.5 million km...
26. The Virgo Coating Collaboration: research lines and preliminary results of a detailed study on thermoelasticity in crystalline materials
Matteo Lorenzini (GSGC)
3/1/18, 12:00 PM
The visibility distance of interferometric gravitational wave detectors is limited by mirror thermal noise at mid-range frequency, where the first coalescence GW signals have been detected and where many others are expected in the next future. In particular, for 2G+ and 3G we need to increase the performance of the test mass multilayer reflective coatings. The Virgo collaboration is setting a...
16. The Virgo Coating Collaboration: a new deposition facility and preliminary results on nano-layered coatings
Dr Maria Principe (SA)
3/1/18, 12:20 PM
Thermal noise in the coatings of the test masses of the ground-based interferometric detectors of gravitational waves is the dominant noise contribution in the most sensitive frequency band, where the first gravitational signals have been detected and where several cosmic sources are deemed to exist. Hence developing coatings with reduced thermal noise is among the primary tasks of the Virgo...
Matteo Lorenzini (GSGC)
3/1/18, 12:40 PM
The performance of present and future gravitational wave detectors is limited by fundamental factors, such as thermal noise, seismic or newtonian noise and quantum nature of light. Besides, technological factors impact the reach of advanced detectors through status of art limits in the implementation of upgrade strategies. In the realm of optics, the quantum limit to sensitivity will be...
Dr Shtefan Danilishin (University of Glasgow)
3/1/18, 2:00 PM
It is hard to overestimate the scientific significance of the 6 confirmed detections of gravitational waves from compact binary sources that Advanced LIGO and Advanced Virgo have jointly made. However, it is still a long way ahead until the sensitivity of GW detectors is high enough to make them fully fledged astronomical tools. The main hindrance on this way remains the quantum noise, the...
Mrs Stefanie Kroker (PTB and TU Braunschweig)
3/1/18, 2:30 PM
Thermal noise is known to be a crucial limitation for high precision sensing devices like future gravitational wave detectors or lasers with extreme narrow linewidths. Mitigating Brownian thermal noise as an important issue requires the reduction of the mechanical loss of involved materials and/or their deliberate spatial distribution. In this contribution we discuss the influence of...
Dr Matteo Leonardi (NAOJ)
3/1/18, 2:50 PM
Kagra is the first 2.5G gravitational wave (GW) detector and it incorporates some very challenging new technologies such as underground facility and cryogenic sapphire mirrors. Another new technology that was not in the base road-map of any GW detector but nowadays is addressed as a crucial upgrade is frequency dependent squeezing. I'll give some highlights on the Kagra detector and...
Dr Antonio Perreca (TIFP)
3/1/18, 3:10 PM
The Laser Interferometer Gravitational-wave Observatory (LIGO) and Virgo have recently opened a new window for astronomy by detecting gravitational-waves from coalescing black holes and from neutron star merger. The LIGO/Virgo Scientific Collaboration is exploring ways to increase range and sensitivity by applying promising new techniques for current and next generation gravitational-wave...
6. Low temperature performances of a monolithic folded pendulum sensor for the third generation of interferometric detectors of gravitational waves
Flavio Travasso (PG)
3/1/18, 3:30 PM
An effective low frequency sensitivity improvement of the next generation of gravitational waves interferometric detectors requires the introduction of new ideas and the development of suitable technologies. Within this framework, the cryogenic suspensions represent a very good synthesis and effective approach to this problem, as already demonstrated by the KAGRA interferometric detector. An...
9. SAR-GRAV: the Sardinia Underground Laboratory, a first module for the Einstein Telescope infrastructure
Luca Naticchioni (ROMA1)
3/1/18, 3:50 PM
Since 2010 the site of Sos Enattos, a former mine in the North-East Sardinia - Italy, was studied with long term seismic investigations in the framework of the site selection for the Einstein Telescope (ET). The site proved to be one of the seismically quietest places in Europe, given the local geological features and the low population density of the island. In particular, in 2012 we realized...
38. MIGA and ELGAR : towards the observation of low frequency gravitational waves using atom interferometry
Dr Philippe BOUYER (CNRS - IOGS)
3/2/18, 2:00 PM
I will review the progress towards large-scale differential gravitational measurement is using an array of Atom Interferometers (AIs) configured to differentiate Newtonian Noise, geodetic signal and GW detection. In this gravitation antenna, each of the AIs measures the local gradient of gravitational acceleration and the correlation between distant sensors enables to cancel out fluctuations...
Mr Miguel Dovale-Alvarez (University of Birmingham)
3/2/18, 2:30 PM
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...
Daniele Vetrugno (T)
3/2/18, 2:50 PM
The LIGO first detection officially opened the era of gravitational waves observation. Few weeks ago, the LISA Pathfinder team published its last results in which it was shown that the residual force noise between two test-masses in a single spacecraft can be reduced and measured at the level required by LISA, the Laser Interferometry Space Antenna. This result represents a milestone in...
29. The Free-fall Experiment Results: measuring subfemto-g acceleration noise in LISA Pathfinder and fN force variations on ground with torsion pendulum, in intermittent control mode
Giuliana Russano (Università di Trento/TIFPA)
3/2/18, 3:10 PM
The relative acceleration between two test masses free falling in orbit is perturbed by the presence of a larger constant relative acceleration that must be actively compensated in order to keep the test bodies centered inside the orbiting apparatus. The actuation force applied to compensate this effect can be applied continuously or can be limited to brief impulses, with test masses in a...
12. PETER: a torsion pendulum facility to study small forces/torques on free falling instrumented masses
Fabio Garufi (NA)
3/2/18, 3:30 PM
We will describe realization and tests of a two stage torsion pendulum facility (nicknamed PETER, from Italian PEndolo Traslazionale E Rotazionale, namely translational and Rotational Pendulum) for the measurement of GRS actuation Cross Talks (CT) and its possible evolution. This project started within the ground testing activities for the characterization, before flight, of the Gravitational...
Martina De Laurentis (NA)
3/2/18, 3:50 PM
One of the oldest questions concerning quantum mechanics and gravitation is whether vacuum fluctuations do gravitate. The question of the weight of vacuum was raised soon after the birth of quantum mechanics and many theoretical attempts were performed to explore the motivations and consequences of assuming or discarding such hypothesis, and jet today there no a complete theretical...