Special Session SS6  27 June 2017

Exploring Neutron Star Structure by Timing and Spectroscopy

Aims and scope

During this event we will focus on the physics of neutron star crusts by discussing pulsar/magnetar glitches and the heating and cooling of the crust caused either by a magnetar outburst or through accretion of matter from a companion star. We will also discuss how the Neutron Star Interior Composition Explorer (NICER) will impact those fields.

Pulsar glitches offer a unique probe to the neutron star interior and structure when the external torque on the pulsar is steady. The dynamics of neutron stars is affected by the recently realized entrainment effect between superfluid/Bloch neutrons and the crust. Some major pulsar glitches accompanied by changes in the external torque and temporary changes in pulsar behaviour (RRATs, intermittency, radio turn-off) or large changes in braking index offer an interesting perspective for our understanding of the internal structure and dynamics. Magnetar glitches offer signatures which are often different from pulsar glitches. Part of this variety probably reflects the variability of external torques. A comparison of pulsar and magnetar glitches in terms of external torque variations and response of the neutron star is of interest.

Magnetars also exhibit outbursts during which their crusts are heated and subsequently cool are possibly heated and then subsequently cool down slowly. Important crust physics can be inferred from their outburst light curves in the context of the cooling model. Neutron stars in X-ray binaries, whose crusts are heated during accretion events and cool down when the accretion has halted, show similar crust cooling curves. Comparisons between magnetars and neutron stars in X-ray binaries can lead to insights in crustal physics that should be consistent with the constraints obtained from glitches.

This event will bring neutron star theorists and observers working on glitches together with those working on neutron-star crust structure and cooling. The key remaining issues and the most promising theoretical and observational paths to resolve those issues will be discussed.

We will also discuss in detail the NICER mission, which is expected to be launched early 2017. Using pulse profile modeling, NICER will put stringent constraints on the equation of state of neutron stars, providing basic input to glitch and cooling models as well as complementing the constraints they provide.

Main Scientific Organizer : Tolga Guver

Deputy Organizers : Rudy Wijnands, Ali Alpar

Scientific Organizing Committee : Zaven Arzoumanian, Nathalie Degenaar, Feryal Ozel, Patrick Weltevrede


  • Pulsar and Magnetar Glitch Research
  • Neutron Star Crusts, Structure, Heating and Cooling
  • Constraining the EOS using NICER and its impact on glitch and cooling research

Invited speakers

  • Zaven Arzoumanian (NASA / GSFC)
  • Nathalie Degenaar (University of Cambridge)
  • Brynmor Haskell (Nicolaus Copernicus Astronomical Center)

Scientific organisers
M. Ali Alpar, Zaven Arzoumanian, Nathalie Degenaar, Tolga Guver, Feryal Ozel, Patrick Weltevrede, Rudy Wijnands

tolga.guver @ istanbul.edu.tr

Updated on Sun Dec 18 08:18:32 CET 2016