Gravitation

"Les couleurs de la découverte"

Découvertes scientifiques et leur place dans la société, de la Terre à l'Univers. Un film avec la participation de Matteo Barsuglia.

 

Validation expérimentale des performances interférométriques de LISA

                  Le projet LISA de détection des ondes gravitationnelles a été sélectionné comme mission ‘Large’ de l’ESA au printemps 2017, pour un lancement prévu en 2034. Cette mission repose sur la capacité à mesurer, par interférométrie optique, l’amplitude des fluctuations de la distance entre trois satellites distants de 2.5 Mkm avec une précision picométrique sur des périodes de temps de quelques secondes à quelques heures.

Cocktail party of ultra-compact binary systems

   In this project we will study a particular problem in Gravitational Waves (GWs) astronomy. While the GW sources which are currently detected with LIGO and VIRGO are rare and of short duration, some GW signals expected in the

Detecting low-frequency gravitational waves

The first detection of gravitational waves (GWs) from coalescing binary black holes by the
LIGO-VIRGO scientific collaboration has opened a new era in astrophysics: gravitational wave
astronomy. The ground based detectors operate at high frequencies (above 10 Hz), and there are
two major world-wide efforts to detect GW st low frequency. The GWs in the nano-Hz band will
be detected with the Pulsar Timing Array (PTA).
Here we use nature-provided detector: we monitor ultra-stable millisecond pulsars which work

Simulations and associated data analysis for realistic LISA configuration / Simulations et analyses de données pour une configuration réaliste de LISA

The Laser Interferometer Space Antenna (LISA) is a large mission of the European Space Agency. It will address the scientific theme of "The Gravitational Universe" by observing gravitational waves sources emitting between 0.02 milliHertz and 1 Hertz. LISA is formed by tree spacecrafts on heliocentric orbits exchanging laser beams over 2.5 millions kilometers in order to measure the deformation of spacetime of few pico-meters due to gravitational waves.

Increasing the science reach of the LIGO-Virgo gravitational-wave detector network by improving the sensitivity and the quality of the Virgo data.

In August 2017 Virgo made its first gravitational-wave detections together with LIGO. The detection of the gravitational-waves emitted by the binary black-hole coalescence (GW170814) and the binary neutron star coalescence (GW170817, with its electromagnetic counterparts GRB170817a and AT2017gfo) had dramatic consequences for astrophysics, cosmology and tests of general relativity.

The gravitational universe: searching for progenitors of gravitational waves

Context: The discovery, by the LIGO-Virgo collaboration on Sept. 14th 2015, of gravitational waves (GW) from the merger of two stellar-mass black holes, applauded by the whole scientific community, was unexpected in terms of astrophysical sources: two such heavy stellar-mass black holes (~30 solar masses) had never been seen before, although now, they likely constitute the tip of the iceberg. From this detection, several questions immediately arose: how can such black holes form, and how many are there in our local Universe and beyond?

Bayesian population study and testing General Relativity with gravitational waves from coalescing binaries

The gravitational wave detectors run by LIGO/VIRGO collaboration have detected 4 gravitational wave (GW) signals from merging BHs. The data from the last (second) observational run are still being analyzed
and more detections might be announced shortly. The ground-based detectors are now offline for the further upgrade, and we expect a significant increase in the detection rate in the next observational period. In addition, the preparations for the space-based GW observatory, LISA, have already started. The LISA data will

Gravitation