Abstract:
Recently, the Fermi-LAT gamma-ray satellite has detected six Giant Molecular
Clouds (GMCs) located in the Gould Belt and the Aquila Rift regions. In half of these objects
(Taurus, Orion A, Orion B), the observed gamma-ray spectrum can be explained using the
Galactic diffused Cosmic Ray (CR) interactions with the gas environments. In the remaining
three GMCs (Rho Oph, Aquila Rift, Cepheus), the origin of the gamma-ray spectrum is still
not well established. We use the GEometry ANd Tracking (GEANT4) simulation framework
in order to simulate gamma-ray emission due to CR/GMC interaction in these three objects,
taking into account the gas density distribution inside the GMCs. We find that propagation
of diffused Galactic CRs inside these GMCs can explain the Fermi-LAT detected gamma-ray
spectra. Further, our estimated TeV-PeV fluxes are consistent with the HAWC upper limits,
available for the Aquila Rift GMC. As last step, we compute the total neutrino flux estimated
for these GMCs and compare it with the IceCube detection sensitivity.
