Scalable CI for Early Warning Gravitational Wave Detections
Start: 2018-10-01
End: 2021-09-30
National Science Foundation
| Physics |
| LIGO |

The recent multi-messenger detection of of the binary neutron star merger known as GW170817 changed astronomy overnight. The source was detected first in gravitational waves, two seconds later in gamma rays and after 10 hours in optical, ultraviolet, infrared, and much later x-ray and radio. From this single event the world learned that the progenitors of at least some short-hard gamma ray bursts are neutron star mergers, the origin of many elements in the periodic table such as gold and platinum might also be neutron star mergers, gravity and light travel at the same speed, and gravitational waves really could measure the expansion rate of the universe! Despite what was learned, GW170817 left the world with many questions. What object was formed afterward? Another neutron star? A black hole? Why was the gamma ray burst associated with GW170817 unlike anything else that had been observed? Data is required to address these questions - specifically electromagnetic data taken right when the neutron stars merged. It is possible to use gravitational wave data, which measures the neutron star before it merges, to automatically direct robotic observations of telescopes across the world and in space. Doing so requires tremendous cyber-infrastructure which is presently lacking.

Using gravitational waves to provide an early warning for robotic telescopes will significantly enhance the scientific utility of LIGO data by enabling multi-messenger astrophysics associated with measuring electromagnetic radiation across the spectrum right as the two neutron stars merge helping to answer what drives some of the brightest objects in the known universe. This project will fortify the streaming data delivery of LIGO by producing sub-second data delivery to a streaming early warning search for neutron star mergers. Substantial monitoring and feedback will be put in place to ensure that the entire system operates without human intervention from the instrument all the way to a public alert within seconds of data taking. The project will capitalize upon existing NSF investments in cyber-infrastructure for real-time gravitational wave analysis, but will augment significantly the layer which handles data delivery and automation, which is presently a bottleneck and failure mode.


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