Topic: Multimessenger astronomy

Ali Kheirandish reviews how high-energy neutrinos are reshaping multimessenger astronomy and searches for new particle physics. IceCube established the astrophysical neutrino signal in 2013; a decade of observations has since revealed directional structure, with emission identified from nearby active galaxies and a smaller contribution from the Milky Way. The seminar examines these measurements, the emerging account of where cosmic neutrinos originate, and opportunities to test physics beyond the Standard Model through the neutrino sector.

Anna Tsai studies how precise pulsar distances can improve localization of individual gravitational-wave sources with pulsar timing arrays. A coherent map-making method uses distance information to approach the diffraction limit, potentially reaching angular precision of about two arcminutes and enabling electromagnetic counterpart searches. At a signal-to-noise ratio of ten, approximately nine pulsars can reach this limit. The resolution improves sharply as more well-timed pulsars have accurately known distances. Since the distance of PSR J0437−4715 is already measured to subparsec precision,