London. Pulsars are fast rotating neutrally magnetised neutron stars that emit pulsed radiation whose regularity surpasses that of atomic clocks. In many cases, however, sporadic increases in the frequency of rotation are observed (glitches). The larger ones are explained by the presence of a neutron superfluid inside the star, which temporarily accumulates rotational energy and then suddenly drops it to the observable crust, accelerating it. Pulsar glitches are therefore macroscopic evidence of superfluid nuclear matter in super-dense matter that allow for us to investigate its properties. In an article published on Nature Astronomy, a group of theoretical physicists led by Pierre Pizzochero, a Professor at the University of Milan and at the INFN (with PhD candidate Marco Antonelli), proposed a realistic model for the rotational energy reservoir based on the interaction with the normal matter of the quantized vortex lines present in the rotating superfluid. (9Colonne)
