With LIGO’s recent observations of gravitational waves, astrophysical phenomena have now been observed using messengers that interact via each of the four fundamental forces of nature. Traditionally, Electromagnetic radiation, of all wavelengths, has been used to learn about the Universe. Auger has now been able to use UHE Cosmic-rays, interacting via the strong force, to identify a probable source for these messengers, opening the possibility of using them to study individual events in the Universe. Weakly interacting neutrinos have been used to observe phenomena since Davis’ ground-breaking solar neutrino experiments and the observations of SN1987a’s neutrino burst. With the new generation of high energy neutrino observatories such as ANITA and ARA experiments (both with KICP involvement) coming online, the community is poised to learn even more about the sources which produce these ghostly particles.
By combining observations obtained by these various methods; i.e. participating in multi-messenger astrophysics, we are poised to greatly amplify what we can learn about the Universe. Nowhere is this more obvious than in the recent observations of the coalescing neutron star system, GW170817. It was initially detected with Gravitational waves by LIGO, which gave the dynamical properties of the system and a distance. Fermi observations revealed a gamma-ray burst source at that location and rapid follow-up observations in the optical, using the DECam and other optical telescopes, quickly revealed the host galaxy. By combining these observations numerous ideas about the nature of these coalesences were quickly confirmed; including their use as an independent method of measuring the Hubble constant.
With its wide involvement in many of the key experiments that observe astrophysical phenomena using each type of messenger, the KICP plays a key role in this emerging field.