Accretion on the eccentric binary system DQ Tau

Hello to everybody, my name is Eleonora Fiorellino, I'm a fellow researcher at the Konkoly Observatory, in Budapest, and these are the interesting results we found analysing DQ Tau spectra, a well know eccentric binary system. Binary systems are interesting to study and test accretion process, even more if they're highly eccentric.

This is the reason why we computed the mass accretion rate of 8 spectra observed with X shooter. As you can see in Fig.2, our results confirm the pulsed accretion model, according to which the mass accretion rate of this binary system is larger nearby the periastron. We also managed to discriminate which star is accreting the most, by following the peaks which have the same radial velocity of the primary and secondary components (Fig.3). In Fig.3, for example, you can see that for epoch 2 (orange line, phi = 0.96) the secondary is accreting the most, while at the previous epoch (blue line, phi = 0.90) the secondary is the main accretor. Fig.4 summarises our results for all the accretion tracers, assigning a red, blue and purple circle to each line and phase depending on the main accretor. We find that the main accretor changes epoch by epoch, up to three times during less than two periods. But why different lines show different main accretors? And what does this imply for the physics involved in the accretion mechanism? If you want the answer, stay tuned for the upcoming paper!