Pulsar rotation with superfluid entrainment

5th Compact Stars in the QCD Phase Diagram

Antonelli, Marco^1 ; Pizzochero, Pierre M.^1

Department of Physics, Università degli Studi di Milano, Istituto Nazionale di Fisica Nucleare, Via Celoria 16, Milan

20133, Italy^1

关键词: Dissipative effects;    Global modeling;    Global models;    Neutron stars;    Normal component;    Pinning forces;    Quantitative tests;    Superfluid component;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/861/1/012024/pdf
DOI  :  10.1088/1742-6596/861/1/012024

来源: IOP

【 摘 要 】

Large pulsar glitches (like the ones detected in the Vela) are though to be a consequence of the superfluid component present in the interior of mature neutron stars: this component can rotate differentially with respect to the normal part of the star, storing the angular momentum needed to produce the observed sudden decrease of the pulsar rotational period. However strong entrainment (a non-dissipative effect that couples the superfluid component with the non-superfluid component inside the star) challenges this picture. Here we study the impact of entrainment on the angular momentum that can be exchanged between the normal component and the superfluid during a glitch by means of a consistent global model. This allows to estimate the maximum angular momentum reservoir stored into the superfluid component of the star: the essential ingredient are newly calculated mesoscopic pinning forces that block the superfluid vorticity in the crust of the neutron star. This method can also provide a quantitative test for global models of rotating neutron stars, as well as for microphysical inputs present in literature (like entrainment parameters and pinning forces).