Unmasking the Remnants of Gamma-Ray Bursts in the Era of Gravitational Wave Astronomy

This award supports research in relativity and relativistic astrophysics and it addresses the priority areas of NSF's "Windows on the Universe" Big Idea. The era of gravitational-wave multi-messenger astronomy started on 2017 August 17, when LIGO (the Laser Interferometer Gravitational Wave Observatory) discovered an event dubbed GW170817. This was the very first direct observation of gravitational waves from a binary neutron star in-spiral, which was accompanied by the detection of light at all wavelengths. The multi-messenger observations of GW170817 have crucially informed a large variety of fields including gravitational physics, nuclear physics, cosmology, and relativistic astrophysics. In spite of the spectacular progress, several questions remain open. A key one is whether the stellar object leftover from the merger is a short-lived neutron star, a long-lived neutron star, or a promptly formed black hole. This award supports searches of LIGO data for signatures aimed at uncovering the nature of the merger remnant. Studying how the nature of the remnant depends on the properties of the merging objects can unlock the fundamental physics of matter at densities much larger than those that can be probed in Earth-based laboratories and clarify the physics of some of the most exotic objects in the stellar graveyard. This project also supports the training of graduate and undergraduate students who will constitute the next generation of scientists, and several outreach activities aimed at presenting LIGO results to the general public and K12 students. Specific intellectual goals are: (i) Unmasking the remnants of compact object mergers accompanied by gamma-ray bursts by carrying out searches for gravitational waves from newly formed neutron stars; (ii) Assessing the efficiency of the newly-developed Cross-Correlation Algorithm (CoCoA) in detecting the full zoo of possible gravitational wave signals from merger remnants, and its efficacy in post-detection parameter estimation; (iii) Quantifying the potential for discovery of gravitational waves from neutron stars formed in long gamma-ray bursts by future upgraded gravitational wave detectors. Broader impact goals are: (i) Bringing age-appropriate presentations and LIGO-related outreach activities to under-represented groups by leveraging the TTU Honors College-Bayless Elementary School mentoring program; (ii) Presenting a LIGO prize to the South Plains Regional Science Fair; (iii) Presenting LIGO results to the general public during the Astronight at TTU. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.