Abstract
The study of the diffuse Galactic gamma ray emission is of fundamental importance to understand the properties of cosmic ray propagation in the Milky Way, and extending the measurements to E ≳ 30 TeV is of great interest. In the same energy range the IceCube detector has also recently observed a flux of astrophysical neutrinos, and it is important to test experimentally if the neutrino production is accompanied by a comparable emission of high energy photons. For E ≳ 30 TeV, the absorption effects due to e + e − pair production when the high energy photons interact with radiation fields present in space are not negligible and must be taken into account. Gamma rays, in good approximation, are completely absorbed if they have an extragalactic origin, but the absorption is significant also for Galactic photons. In this case the size and angular dependence of the absorption depends on the space distribution of the emission. In this work we estimate the absorption for different models of the space distribution of the gamma ray emission, and discuss the potential of future detectors.
Highlights
The observation of the diffuse Galactic gamma ray emission allows to study the space and energy distribution of cosmic rays (CR) in the Milky Way
The absorption is significant for photons travelling for intergalactic distances, making impossible to detect gamma rays of energy above 30 TeV unless the sources are very close to our Galaxy (z < 0.01)
In this paper we describe the effects of the absorption on a Galactic gamma ray flux, assuming different distributions of the sources, according to some models proposed in the literature on the possible origin of the IceCube neutrinos
Summary
The observation of the diffuse Galactic gamma ray emission allows to study the space and energy distribution of cosmic rays (CR) in the Milky Way. The large field of view of the future air shower arrays, as LHAASO, will allow the measurement of diffuse fluxes, as those produced by cosmic ray interactions in the interstellar medium or originating by other processes inside our Galaxy. The absorption is significant for photons travelling for intergalactic distances, making impossible to detect gamma rays of energy above 30 TeV unless the sources are very close to our Galaxy (z < 0.01). At these energy, the absorption is not negligible for Galactic gamma rays, and modifies the spectrum with an absorption pattern that depends on the source spatial distribution. In this paper we describe the effects of the absorption on a Galactic gamma ray flux, assuming different distributions of the sources, according to some models proposed in the literature on the possible origin of the IceCube neutrinos
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
