Speaker
Description
The Galactic Plane has been established as a source of high-energy neutrino emission with a significance beyond 5 sigma using Galactic diffuse neutrino emission models. We discuss the results of a model-independent measurement of the Galactic emission with 10 years of IceCube cascade data, which provides confidence intervals on the neutrino flux and the spectral index in different regions of the Galactic Plane at TeV energies.
For the inner Galactic region $|l|<30^{\circ}, |b| < 8^{\circ}$, the average per-flavor neutrino flux $E_{\nu}^2\Phi_{\nu+\bar\nu}$ at $E_\nu=5\,\mathrm{TeV}$ in units of $10^{-11}\,\mathrm{TeV\,m^{-2}\,s^{-1}\,sr^{-1}}$ is measured to be $21.4^{+6.3}_{-5.2}$ while for the outer Galactic Plane $|l|>60^{\circ}, |b| < 8^{\circ}$ it is measured to be $4.3^{+2.6}_{-2.4}$. The spectral index fit in the inner and outer region is $\gamma = 2.76^{+0.17}_{-0.15}$ and $\gamma = 3.10^{+0.40}_{-0.39}$, respectively.
For the first time, a direct comparison between the neutrino measurement and TeV gamma-ray emission reported by LHAASO is performed in the same region of the Galactic Plane. This is made possible by the model-independent nature of this measurement, which provides flux estimates in specific regions rather than relying on full-sky spatial templates. The results of this analysis, combined with improved data samples from IceCube and new data from KM3NeT, demonstrate that it is becoming possible to test models of Galactic diffuse emission, make direct comparisons between neutrino and gamma-ray measurements, and ultimately directly constrain the hadronic fraction of gamma-ray observations in the plane of the Galaxy.
