Diffuse Emission of High-Energy Neutrinos from a Global Fit to Cosmic Rays

Model of diffuse emission of high-energy neutrinos from a global fit of cosmic rays and model of high-energy neutrino emission from unresolved pulsar-powered sources.

The maps presented in the form of HEALPix maps (Gorski et al 2005, ApJ, 622, 759) of per-flavor intensity in units of GeV^-1 cm^-2 s^-1 sr^-1 at 50 logarithmically spaced energies between 10 GeV and 10⁸ GeV. We use a value of NSIDE=256 and the RING binning scheme.

We here make available our fiducial model, which is calculated assuming the Ferrière 2001 cosmic ray source distribution, the AAfrag hadronic production cross sections and the GALPROP gas maps. We calculated the emission from unresolved sources following Vecchiotti et al. 2022, ApJ, 928, 19.

In Version 2 of this dataset, we also make available the local cosmic ray fluxes of our fiducial model obtained from a global fit to cosmic ray data together with the corresponding 68% and 95% uncertainty bands. These are shown in figure 6 of arXiv:2211.15607. The nuclear fluxes are in (GeV/n)^-1 m^-2 s^-1 sr^-1, the fluxes of electrons and positrons are in GeV^-1 m^-2 s^-1 sr^-1 . The fluxes are local interstellar fluxes without solar modulation.

In Version 3 of this dataset, we add the fiducial diffuse gamma ray model calculated assuming the Ferrière 2001 cosmic ray source distribution, the AAfrag hadronic production cross sections as well as the GALPROP gas maps and ISRF model. We separately make available 3 maps: The hadronic emission on neutral atomic gas, the hadronic emission on molecular gas and the leptonic emission from Inverse Compton Scattering. 

Similar to the dataset of the fiducial neutrino model, the maps are presented in the form of HEALPix maps (Gorski et al 2005, ApJ, 622, 759) in units of GeV^-1 cm^-2 s^-1 sr^-1. We use a value of NSIDE=256 and the RING binning scheme. For the hadronic maps, the intensity is given at 50 logarithmically spaced energies between 10 GeV and 10⁸ GeV. For the leptonic maps from Inverse Compton Scattering, the intensity is given at 48 logarithmically spaced energies between 1 GeV and 10⁶ GeV.

The structure of the files is somewhat different from the file containing the fiducial neutrino model. This is to allow for easy use of the gamma ray maps with the gammapy package (Deil et al. 2017, arXiv:1709.01751).

Also available in Version 3 are the full spatio-spectral cosmic ray distributions in the Milky Way as predicted by our fiducial model. The nuclear fluxes are given for each species in (GeV/n)^-1 m^-2 s^-1 sr^-1 at 63 energies between 1 GeV and 10⁹ GeV. The leptonic fluxes are given for each species in GeV^-1 m^-2 s^-1 sr^-1 at 36 energies between 1 GeV and 10⁵ GeV. 

All fluxes are given on a spatial grid at 81 galactocentric radii from 0 kpc to 20 kpc and 61 distances perpendicular to the galactic plane between -6 kpc and 6 kpc.

Finally, a word of caution about the extra component of cosmic ray leptons included in our model: This component is contained in the last HDUnit of the fits file containing the leptonic cosmic ray distributions. It is there denoted as a flux of electrons. It must, however, also be added to the flux of positrons to achieve correct results.

Please refer to arXiv:2211.15607 for further details.

When using these models in your research work, please refer to this Zenodo dataset and the publication.