Speaker
Lorenzo Ducci
(University of Tuebingen)
Description
Glitches have been observed in isolated pulsars, while a
clear detection in accretion-powered X-ray pulsars is still lacking.
We use the "snowplow" model for pulsar glitches of Pizzochero
(2011) and starquake models to determine for the first time the
expected properties of glitches in accreting pulsars. We also
investigate the possibility that anti-glitches occur in accreting
pulsars which show accretion-induced long-term spin-up. We find
that glitches caused by quakes in a slow accreting neutron star are
very rare and their detection extremely unlikely. On the contrary,
glitches and anti-glitches caused by a transfer of angular
momentum between the superfluid neutron vortices and the non-
superfluid component may take place in accreting pulsars more
often. We calculate the expected maximum jump in angular
velocity of an anti-glitch and we also find that both glitches and
anti-glitches in accreting pulsars are expected to have long rise
and recovery time scales compared to isolated glitching pulsars.
We find that, among accreting pulsars, GX 1+4 is the best
candidate for the detection of glitches with currently operating
X-ray satellites.
Primary author
Lorenzo Ducci
(University of Tuebingen)
Co-authors
Prof.
Andrea Santangelo
(University of Tuebingen)
Dr
Carlo Ferrigno
(University of Geneva)
Prof.
Pierre Pizzochero
(Università di Milano)
Dr
Sandro Mereghetti
(INAF-IASF Milan)
Dr
Victor Doroshenko
(IAAT, University of Tuebingen)
