CompOSE : compare and contrast

Recently I discovered a service called CompOSE (CompStar Online Supernovae Equations of State) that looks related to what MUSES aims to achieve. Who can provide more insight into this service and compare and contrast it with the MUSES project?

The CompOSE website says:

The online service CompOSE provides data tables for different state of the art equations of state (EoS) ready for further usage in astrophysical applications, nuclear physics and beyond.

The published manual of the CompOSE service:

This paper is the manual of the CompOSE service, see this http URL, an equation of state (EoS) database for use in nuclear physics and in astrophysical applications, e.g. the simulation of core-collapse supernovae and compact stars. The main aims of the service are the following: to offer a robust, easily extendable data format to store and read EoS data tables and related physical quantities; to make these data available to the public – respecting the original work by the contributors – in a standard format designed for easy access and flexibility; and to provide routines to interpolate these data in the parameter space of density, temperature and hadronic charge fraction. The manual contains a detailed description of the service. It is divided into three parts, containing a general introduction as well as instructions for potential contributors and for users.


HI @andrew.manning some of our members (@vdexheim ) here are involved in COMPOSE. The key difference is that COMPOSE only provides the data tables and not the code itself. Since many of the codes have unknown parameters, specific assumptions, etc then only with the code itself do you have the possibility to improve through new particles, interactions etc.

Additionally, their primary focus is neutron stars at T=0 so they miss the entire heavy-ion community. Nor do they provide observable codes like the TOV, bulk viscosity, thermal fits etc that we are planning.

The latest CompOSE manual (v3) claims that

CompOSE can provide information on additional thermodynamic quantities, which
are not stored in the original data tables, and on further quantities, which charac-
terize an EoS, such as nuclear matter parameters and compact star properties.

Can someone explain what this means and how it differs from our “observables” or “user” modules?

Hi Andrew,

From what I understand, they’ll provide a table and list relevant input parameters (like symmetry energy). For that specific table they’ll also provide a separate table of observables like M-R curves or tidal deformabilities.

Those would be the same observables that we have. However, instead of a table we are creating a code to do that. In fact, most everyone has a code like this but we’re making a very quick one (what Hung is working on) that is open source and also can provide I-LOVE-Q values (not always available from all codes) and can obtain a higher order (more precise) for rotations.

Additionally, we’ll have a lot of other observables/user modules beyond that. They don’t have anything for heavy-ion collisions, nor lattice QCD, nor transport coefficients, nor thermal fits etc.

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