Estimating Source of Galactic Neutrinos

This master’s thesis focuses on the identification of potential neutrino sources within our galaxy and provides valuable insights into the origin of cosmic rays. Neutrinos and gamma rays are expected to be produced simultaneously in proton-proton (pp) interactions. By establishing a correlation between the spectra of these two particles, we aim to identify and understand the potential sources of galactic neutrinos. We have developed a model that quan- tifies the relationship between the predicted neutrino fluxes and gamma-ray fluxes. We utilized a synthetic dataset of 3000 very high-energy (VHE) gamma-ray sources provided by [1] to predict neutrino sources in the Milky Way. The populations were a combination of observed and simulated gamma-ray sources modeled as a 4-arm spi- ral structure with various parameters, including Galactic coordinates, circular extent, distance, luminosity, radius, and integrated flux. Applying our developed model to these sources, we successfully predicted the corresponding neutrino emissions. To assess the accuracy of our predictions, we compared the calculated total predicted neutrino flux with the diffuse flux observed by IceCube and the upper limit established by ANTARES. Our results indicate that our total predicted neutrino flux from galactic sources is lower than the overall neutrino flux observed by neutrino detectors, as our model specifically focuses on neutrinos originating within our galaxy which is a subset of all the possible sources of neutrinos. Furthermore, we generated sky maps using the Gammapy package in Python to visualize the flux of the predicted sources and their spatial distribution across the galactic plane. Additionally, a comparison with observed neutrino events from the ANTARES neutrino detector was conducted to investigate the correspondence between the predicted sources and observed events. On average, our model predicted 53 counts for ANTARES and 240 counts for KM3NeT which are lower than the 747 actual event counts recorded by ANTARES. This was consistent with our expectations since neutrino detectors, such as ANTARES, detect both astrophysical and atmospheric neutrinos. Moreover, spatial positions of ANTARES events in the galactic plane do not conclusively prove that these events originate from galactic sources. In conclusion, this research offers insights into the origins of galactic neutrinos. Further investigations, including multi-wavelength correlations and advancements in neutrino telescopes, hold great potential for improving our understanding of these sources and unraveling the mysteries of the universe.