Detecting superfluid transition in the pulsar core
arXiv:2403.11539 · doi:10.1093/mnras/stae1642
Abstract
It is believed that the core of a neutron star can be host to various novel phases of matter, from nucleon superfluid phase to exotic high baryon density quantum chromodynamics (QCD) phases. Different observational signals for such phase transitions have been discussed in the literature. Here, we point out a unique phenomenon associated with phase transition to a superfluid phase, which may be the nucleon superfluid phase or a phase like the CFL phase, allowing for superfluid vortices. In any superfluid phase transition, a random network of vortices forms via the so-called Kibble-Zurek mechanism, which eventually mostly decays away, finally leaving primarily vortices arising from the initial angular momentum of the core. This transient, random vortex network can have a non-zero net angular momentum for the superfluid component, which will generally be oriented in an arbitrary direction. This is in contrast to the final vortices, which arise from initial rotation and hence have the initial angular momentum of the neutron star. The angular momentum of the random vortex network is balanced by an equal and opposite angular momentum in the normal fluid due to the conservation of angular momentum, thereby imparting an arbitrarily oriented angular momentum component to the outer shell of the neutron star. This will affect the pulse timing and pulse profile of a pulsar. These changes in the pulses will decay away in a characteristic manner such that the random vortex network decays, obeying specific scaling laws leading to universal features for the detection of superfluid transitions occurring in a pulsar core.
9 pages, no figures
References in corpus (12)
- Color superconductivity in dense quark matter
- Rapid Cooling of the Neutron Star in Cassiopeia A Triggered by Neutron Superfluidity in Dense Matter
- Models of Pulsar Glitches
- Vortex pinning in the superfluid core of neutron stars and the rise of pulsar glitches
- Simulation of Z(3) walls and string production via bubble nucleation in a quark-hadron transition
- Constraints on neutron star superfluidity from the cooling neutron star in Cassiopeia A using all Chandra ACIS-S observations
- Effects of Phase Transition induced density fluctuations on pulsar dynamics
- Pulsar timing and its applications
- Gapless neutron superfluidity can explain the late time cooling of transiently accreting neutron stars
- Exploring the Phase Diagram of V-QCD with Neutron Star Merger Simulations
- Modulation of pulse profile as a signal for phase transitions in a pulsar core
- The Efficiency of Defect Production in Planar Superconductors and Liquid Crystals