Search for Extended Galactic Sources of Astrophysical Neutrinos with the Icecube Neutrino Observatory

Download or read book Search for Extended Galactic Sources of Astrophysical Neutrinos with the Icecube Neutrino Observatory written by Devyn Rysewyk Cantu and published by . This book was released on 2021 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt: The IceCube Neutrino Observatory0́4a cubic-kilometer of instrumented ice at the geographic South Pole0́4has been observing a high-energy astrophysical neutrino flux since 2010. However, a steady source of these neutrinos is yet to be identified. Possible candidates contributing to the high-energy neutrino flux include extended sources (spanning a few degrees) originating from within the Milky Way. Such sources have been discovered in the very-high-energy gamma-ray sky along the Galactic plane with experiments such as HAWC and H.E.S.S. If the emission from these extended sources is of a hadronic origin, an associated flux of neutrinos from the decay of pions is also expected to be observed. Therefore, an observation of neutrino emission from these extended gamma-ray sources would provide direct insight into cosmic-ray acceleration in the galaxy. Two approaches to performing dedicated searches for extended sources along the Galactic plane with nine years of IceCube data will be discussed. With these two approaches, no significant sources were found and the results are consistent with background.While IceCube has revealed the existence of sources of high-energy astrophysical neutrinos, the identification of the sources is challenging because astrophysical neutrinos are difficult to separate from the background of atmospheric neutrinos produced in cosmic-ray-induced particle cascades in the atmosphere. The efficient detection of air showers in coincidence with detected neutrinos can greatly reduce those backgrounds and increase the sensitivity of neutrino telescopes. Imaging Air Cherenkov Telescopes (IACTs) are sensitive to gamma-ray-induced (and cosmic-ray-induced) air showers in the 50 GeV to 50 TeV range, and can therefore be used as background-identifiers for neutrino observatories. The feasibility of an array of small scale, wide field-of-view, cost-effective IACTs as an air shower veto for neutrino astronomy will be discussed. A surface array of 250 to 750 telescopes would significantly improve the performance of a cubic kilometer-scale detector like IceCube, at a cost of a few percent of the original investment. The number of telescopes in the array can be optimized based on astronomical and geometrical considerations.