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.

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?

LIGO/VIRGO collaboration has announced 4 confirmed detection of gravitational wave (GW) signals
from the merging binary black holes. This opens a new window in the astronomy: gravitational wave astrophysics.
There are three major efforts to search for GWs: LIGO-VIRGO detectors operating in the frequency range
between few Hz and kHz, LISA - space based detector which will be launched in 2034 and is sensitive
in the milli-Hertz band, PTA (Pulsar Timing Array) - uses the monitoring of millisecond (stable) pulsars
to detect GWs in the nano-Hertz band.

In late 2015, the Advanced LIGO-Virgo collaboration announced the first detections of a number of binary black holes using gravitational waves.  These detections have opened up the new field of gravitational wave astronomy.  In the next few years, there are a number of planned science runs that should provide many more detections.  An important aspect of the detection process is the fast and accurate estimation of the astrophysical parameters of the system.  We currently collaborate with 83 telescopes, satellites and neutrino detectors around the world.  To search for an electromagnetic cou