Thermal secrets uncovered in neutron star mergers through gravitational waves

Binary simulation neutron star This merger suggests that future detectors will distinguish between different models of hot nuclear material.

Researchers used supercomputer simulations to investigate the effects of neutron star mergers gravitational waves, found a significant relationship with debris temperature. This research will aid future advances in the detection and understanding of hot nuclear materials.

Exploring neutron star mergers and gravitational waves

When two neutron stars orbit each other, they emit ripples into spacetime called gravitational waves. These ripples drain energy from the orbit until the two stars eventually collide and combine into one object. Scientists used supercomputer simulations to investigate how the behavior of different models of nuclear material affects the gravitational waves released after these mergers. They found a strong correlation between the temperature of the debris and the frequency of these gravitational waves. Next generation detectors will be able to distinguish these models from each other.

Plot comparing density (right) and temperature (left) for two different simulations (top and bottom) of a neutron star merger, viewed from above, approximately 5 ms after the merger.Credit: Jacob Fields, Pennsylvania State University

Neutron Star: Institute for Nuclear Materials

Scientists use neutron stars as laboratories for nuclear materials under conditions that would be impossible to explore on Earth. They will use current gravitational wave detectors to observe neutron star mergers and learn how cold, ultra-dense matter behaves. However, these detectors cannot measure the signal after the stars have merged. This signal contains information about hot nuclear material. Future detectors will be even more sensitive to these signals. Because different models can also be distinguished from each other, the findings suggest that future detectors could help scientists create better models of hot nuclear material.

Detailed analysis of neutron star mergers

The study investigated neutron star mergers using THC_M1, a computer code that simulates neutron star mergers and accounts for the bending of spacetime due to the star’s strong gravitational field and neutrino processes in dense matter. . The researchers tested the effect of heat on mergers by varying the specific heat capacity of the equation of state, which measures the amount of energy required to raise the temperature of neutron star material by one degree Celsius. To ensure the robustness of their results, the researchers ran their simulations at two resolutions. They repeated the high-resolution run using a more approximate neutrino processing.

References:

“Thermal effects in binary neutron star mergers” by Jacob Fields, Aviral Prakash, Matteo Breschi, David Radice, Sebastiano Bernuzzi, and Andre da Silva Schneider, July 31, 2023. of Astrophysics Journal Letter.
DOI: 10.3847/2041-8213/ace5b2

“Identification of nuclear effects in neutrino-carbon interactions in low 3 momentum transfer” until February 17, 2016 physical review letter.
DOI: 10.1103/PhysRevLett.116.071802

Funding: This research was primarily funded by the Department of Energy, Office of Science, Nuclear Physics Program. Additional funding was provided by the National Science Foundation and the European Union.

This research used computational resources available through the National Energy Research Scientific Computing Center, the Pittsburgh Supercomputing Center, and the Pennsylvania State University Computing and Data Science Institute.