Session K02: Multi-messenger Astrophysics in the Era Next-generation Gravitational Wave Detectors

Multi-messenger Astrophysics in the Era of the Next-generation Gravitational Wave Detectors

After the landmark event GW170817, the frontier is now to map the properties of a population of neutron star mergers, and connect the pre-merger to the post-merger properties of these events, as constrained by their gravitational wave emission and electromagnetic radiation. In this talk I will review the exciting prospects enabled by the next generation of gravitational wave detectors.   

Multi-messenger astrophysics with continuous gravitational waves in the XG era

Continuous gravitational waves from spinning neutron stars are on the new frontiers of gravitational wave astrophysics and have strong connections to electromagnetic astronomy and nuclear astrophysics. I discuss prospects for detection of various populations, especially aided by electromagnetic observations, before and during the era of next generation (XG) detectors. Then I survey what can be learned from detections. Since continuous gravitational wave emission mechanisms depend on aspects of neutron star physics such as crustal stresses, which are not well constrained by current observations and nuclear experiments, gravitational waves may tell us a great deal that is new. Even more can be learned by combining gravitational wave observations with data from the Next Generation Very Large Array and other electromagnetic detectors operating in the XG era.   

Toward an Understanding of the Core Collapse Supernova Central Engine and Supernova Gravitational Wave Emission

We live in exciting times. On one front, significant progress has been made in the past decade. Based on increasingly sophisticated three-dimensional multi-physics simulations of core collapse supernovae, the efficacy of neutrino-heating as the driver of explosion, assisted by multidimensional effects such as turbulent convection and the standing accretion shock instability, or SASI, has been demonstrated. Explosions have been obtained across the leading modeling groups and across progenitor characteristics, such as mass, rotation, and metallicity. On another front, a new window on the Universe has opened. Gravitational wave astronomy provides an opportunity to look deep into the supernova's core, to gather information about the "central engine." And the continuing prospects brought to us by neutrino astronomy, as well as astronomy across the electromagnetic spectrum, make this an ideal time to be a supernova modeler and to work fervently to prepare for the next Galactic event. Important work remains. Three-dimensional general relativistic models with complete neutrino physics do not yet exist, only sophisticated approximations of them. Nonetheless, current modeling is allowing us to develop a sophisticated understanding of the anatomy of a core collapse supernova gravitational wave signal and its underlying sources. In turn, this is driving the development of techniques to detect and analyze gravitational wave signals and, with that, efforts to extend the range of detectability given the low Galactic and near-extra-Galactic supernova rate, and to maximize the astrophysical information – for example, about the stellar progenitor or remnant neutron star – that can be culled from a detection. I will report on the status of core collapse supernova modeling, including explosion and gravitational wave modeling, on the efforts of the UT–ORNL group, as well as on the challenges that lie ahead if we are to take full advantage of the eventuality of a Galactic supernova.