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The program will bring together nuclear physicists, astrophysicists, observational astronomers and gravitational-wave physicists to address key issues and identify new directions in the study of the inspiral and merger of binary neutron stars. The focus will be on the theoretical modeling, with realistic nuclear and neutrino microphysics, of the late stages of binary coalescence and opportunities for multi-messenger observations. Large-scale numerical simulations of the merger and the dynamics of the remnant are now being pursued by several groups world-wide with a level of realism that was unthinkable a few years back. Meanwhile, the first direct detection of gravitational waves from inspiraling and merging binaries is expected once advanced detectors such as LIGO and Virgo stars taking data in their upgraded configurations in 2017. The intrinsically multi-physics and multi-messenger aspects of binary inspirals emphasize the need for better coordination between theoretical, experimental and observational efforts and provide the backbones of the program.

The schedule for the 5 week program is designed to foster interactions among theorists, experimentalists and observers. Discussion topics include realistic numerical simulations, gravitational-wave waveforms modeling and searches, electromagnetic counterpart signals and gamma-ray bursts, nuclear physics including superfluidity, complex hydrodynamics, neutron star seismology and nucleosynthesis. During the last week a workshop will bring together experts working on nucleosynthesis of heavy elements and galactic chemical evolution.

• Week 1: Gravitational waves: Modeling waveforms, parameter estimation, advanced detectors and extracting physics from merger signals.


• Week 2: Numerical Relativity: Status and challenges, incorporating realistic nuclear and neutrino physics, magnetohydrodynamics, dissipative effects and contributions from the crust.


• Week 3: Dense matter physics: Equation of state, neutrino interactions, neutron star seismology and superfluid dynamics, effects of temperature and magnetic fields on matter.


• Week 4: Merger astrophysics: Modeling electromagnetic signals, crust and disk dynamics and connections to gamma-ray bursts and transients.


• Week 5: Joint workshop with the program on nucleosynthesis and chemical evolution. Workshop webpage

From the perspective of both theory and observations, the diverse phenomena covered by the program have much in common. Simulations rely on the development of improved microphysics models, transport methods for radiation, heat, and neutrinos, hydrodynamics, and nuclear reaction networks. Gravitational-wave observations require reliable theoretical models to identify the signal and facilitate the extraction of physical parameters. Observers will also benefit greatly from deeper insights into key multi-messenger aspects. On the verge of the first gravitational-wave observations, we expect to make considerable progress by bringing together researchers with overlapping interests and expertise on issues that require interdisciplinary information, thus facilitating collaboration and discussion that might otherwise not take place.