Monitoring Pulsar Radio

Between 50 and 60% of the observing time of the Nançay Large Decimeter Radio Telescope (NRT) is now dedicated to L- and S-band observations of pulsars, magnetized neutron stars from which we receive periodic radio pulses. The main stand-alone use of the LOFAR FR606 station at Nançay is the detection of astrophysical transients, for which the observation of low-frequency pulsars is an essential application. Similarly, the observation of pulsars at very low radio frequencies by NenuFAR is one of the key programs of the telescope under construction at Nançay.

These long-term pulsar monitoring observations are aimed at several national and international astronomical communities. The first involves characterizing multi-wavelength emission and the physics of pulsars. The second involves their use as cosmic clocks (enabling tests of gravitational theories, for example) and detectors of gravitational waves in the nHz range. The third concerns the use of signal dispersion to study the electronic content and turbulence of the interstellar medium.

This observation service involves the regular radio monitoring of pulsars of interest to the community. Tasks include the development and maintenance of instruments specifically for radio pulsar observations, the definition of lists of pulsars to be tracked in interaction with the community, the planning of observations, the taking of data, data storage, then automated processing using codes specific to our data. The various products of these timing observations are then distributed to the community, after being verified in consultation with partner teams. For the moment, automated processing and distribution only concern NRT data, but an extension to data from other instruments at the Nançay station is envisaged.