Extreme Matter in Extreme Stars 2024

Registration for the open call is now closed. 

Neutron stars are the Universe’s best laboratories for studying dense matter physics. They provide a unique site where physics can be probed at high densities, low temperatures and high isospin asymmetry, unattainable using terrestrial collider experiments. Formed during the gravitational collapse of massive stars, the inner cores of neutron stars are so dense that they may contain exotic matter, such as quark matter or hyperonic matter, that does not exist anywhere else in the universe and on which we therefore have very few theoretical constraints. They are described by an equation of state (EOS) for strongly interacting matter which is of great interest to nuclear physics and astrophysics. Providing input for these fields motivates strong theoretical, experimental, and observational efforts to elucidate the properties of dense matter at supra-nuclear densities.

The scientific goals of the XMXS 2024 workshop are to encourage a critical examination of individual pieces of data, their robustness and needed precision, to form a better understanding of the new results and obtain robust and reliable constraints on the EOS of dense matter. To achieve this, the workshop will be organised around discussion, planning and writing for a white paper by the workshop participants, including early career scientists. This community-driven document will focus on the current and future probes of dense matter, experimental, astrophysical and theoretical, that would inform neutron star science, as well as how the communities can move forward together.

The highly-interactive workshop will promote developing a common language and discussing desired inputs and possible outputs, intending to foster new collaborations between researchers from different communities (NS astrophysics, GW astrophysics, and theoretical/experimental nuclear physics). The workshop program will focus intensively on discussion sessions and the use of breakout rooms articulated around a few review presentations by key participants, and some "pop-up talks" sessions will which be planned during brief daily organisation sessions. 

The following topics will be addressed during the working:
- Theory of dense matter and EoS modelling
- Experimental constraints of dense matter properties (heavy ion collisions)
- NS radius/mass (EM bulk properties)
- GW tidal constraints
- Crustal constraints and matter below nuclear saturation density
- Nuclear physics of transport in neutron stars
- Future facilities and long term recommendations