Galactic Diffuse Emission Spectrum between 0.5 and 8.0 MeV and between 30 keV and 8 MeV for the search of PBH and Light Dark Matter

Spectra and response files of the soft gamma-ray spectrum from Inverse Compton scattering in the Milky Way between 0.5 and 8.0 MeV, measured with INTEGRAL/SPI. The fluxes have been extracted with spimodfit assuming GALPROP v56 models according to Voyager 1, AMS-02, and Fermi/LAT data, plus different variants to change the interstellar radiation field, the diffusion properties, or the cosmic-ray halo size (Siegert et al., 2022). The respective galdef files are included. In particular:

• voyager: propagation model of Bisschoff et al. (2019), Table 2
• voyager_Dg10001: \(\delta_1 = 0\)
• voyager_Dg1Dg205: \(\delta_1 = \delta_2 = 0.5\)
• voyager_ISRFopt10: factor 10 stronger optical ISFR
• voyager_z8kpc_KL: thick halo with 8 kpc half-thickness

In addition, there are spectra from 30 keV to 8 MeV (spec_0030-8000keV_<name>.fits, Berteaud et al., 2022), separated into:

• CV: spectrum of unresolved point sources in the Galactic plane, mostly cataclysmic variables (strong systematics)
• IC: spectrum of Inverse Compton scattering of cosmic ray GeV electrons (see above)
• positronium: spectrum of positronium decay (annihilation of electrons with positrons after intermediate bound state)
• NFW: spectrum of dark matter contributions that would follow a Navarro Frenk White density profile (mostly consistent with zero)
• total: spectrum of the above combined

The notebooks for dark matter related bounds when using this data as well as auxiliary files to create the templates are given as (Berteaud et al., 2022, Calore et al., 2023):

• DM_fsr.ipynb: Notebook for final state radiation bounds
• DM_fsr.py: astromodels function for final state radiation spectrum
• DM_2gamma.ipynb: Notebook for gamma gamma final state bounds
• DM_2gamma.py: astromodels function for gamma gamma spectrum
• Positronium_Spectrum.py: astromodels function for Positonium spectrum
• DM_pbh.py: script for obtaining PBH bounds
• diff_@@.csv: spectra for PBH evaporation
• total_spectrum.fits.gz: total Galactic spectrum
• NFW_spectrum.fits.gz: NFW-only spectrum