Paul Lagabbe

• Paul Lagabbe (LAPP)

Calibration of Advanced Virgo+ and verification of the reconstructed gravitational wave signal with a photon calibrator To reconstruct the strain signal hrec, models of the interferometer response, and of the mirror electromagnetic actuators response are needed. The photon calibrator give the mirror a known motion thanks to the radiation pressure of an auxiliary laser. The motion of the mirror is computed with the power of the laser reflected by the mirror. This power is estimated by photodiodes which measure a pickoff of the laser. Thus, the powers of these pickoffs should be proportional to reflected power, and the photo- diodes need to be absolutely calibrated. The photodiodes are calibrated with respect to standard power sensors, the integrating spheres. The timing of the PCal also has to be measured.

Matteo Pracchia

• Matteo Pracchia (LAPP)

We perform a joint gravitational waves/gamma-ray bursts (GW/GRB) Bayesian analysis in order to put constraints on the low-luminosity end of the short gamma-ray burst (sGRB) population. For this purpose we exploit the results of the modeled search for GW transients associated to short and ambiguous GRBs detected during the first three observing run LIGO/Virgo network and a broken power law to describe the luminosity function of our sGRB population. We use then the results obtained to have an estimate of the rate distribution of the low-luminosity sGRB population and on the joint detection rate between sGRB and GW for the next two future runs.