This award supports research in relativity and relativistic astrophysics, and it addresses the priority areas of NSF's "Windows on the Universe" Big Idea. NSF LIGO’s detection of gravitational waves from a binary neutron star merger in coincidence with electromagnetic signals from gamma-rays to radio opened a window into the interiors of neutron stars. These stars contain matter under the most extreme conditions since the Big Bang. Long-lived continuous gravitational waves associated with pulsars and supernova remnants and short bursts associated with gamma-ray flares of highly magnetized neutron stars, once detected, will yield even more information on neutron star interiors. The planned Cosmic Explorer detector will push the frontiers forward by enabling detection of many neutron star mergers and probably a variety of other signals. The science goals of this award are to conduct cutting edge searches for these novel signals and improve the extraction of astrophysical information from present and future signals. This award supports the training of graduate and undergraduate students at a Hispanic Serving Institution. Students will be trained not only in gravitational physics, data analysis, and astrophysics, but in cutting edge computational and statistical techniques that are transferable to many areas of science and technology. This award also supports public outreach through the Cosmic Explorer web site.<br/><br/>The main research activity of this award is searches for continuous gravitational waves from young neutron stars, including r-mode oscillations of known pulsars as well as searches of supernova remnants and other likely locations of non-pulsing neutron stars. This award also contributes to searches for a variety of signals including neutron star binary mergers and bursts associated with magnetar flares and to the extraction of astrophysical information from detections present and future. In preparation for the detection of non-merger signals the award supports exploration of detectability and what can be learned about neutron stars now and in the era of Cosmic Explorer.<br/><br/>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.