Orateur
Description
Pulsar Timing Array (PTA) projects intend to detect low-frequency gravitational waves (GWs) by probing their imprints on times of arrival (TOAs) of pulsar radio signals. PTAs are sensitive to nanohertz GWs, corresponding for instance to the emission from super-massive black hole binaries (SMBHBs). One expects to measure the superposition of continuous GWs originating from the cosmic population of such objects as a stochastic signal. Individual nearby massive systems could also produce a detectable GW signal that rises above the gravitational wave background. Precise and high cadence pulsar timing observations are carried out over a long time span in order to obtain highly accurate (sub mu-s) pulsar TOA residuals. Observed with the Nançay Radio Telescope since 2004, PSR J1909-3744 is one of the most stable pulsar known today (timing precision < 100 ns). I will present some preliminary results on a gravitational wave background upper-limit study for this pulsar.
