Li, TJ (reprint author), Chinese Acad Sci, Inst Theoret Phys, State Key Lab Theoret Phys, Beijing 100190, Peoples R China.
[Li, Tianjun] Chinese Acad Sci, Inst Theoret Phys, State Key Lab Theoret Phys, Beijing 100190, Peoples R China
We describe a methodology for testing no-scale supergravity by the LAT instrument onboard the Fermi Space Telescope via observation of gamma ray emissions from lightest supersymmetric (SUSY) neutralino annihilations. For our test vehicle we engage the framework of the SUSY grand unified model no-scale flipped SU(5) with extra vector-like flippon multiplets derived from F-theory, known as F-SU(5). We show that through compression of the light stau and light bino neutralino mass difference, where internal bremsstrahlung photons give a dominant contribution, the photon yield from annihilation of SUSY dark matter can be elevated to a number of events potentially observable by the Fermi-LAT in the coming years. Likewise, the increased yield in no-scale F-SU(5) may also have rendered the existing observation of a 133 GeV monochromatic gamma ray line visible, if additional data should exclude systematic or statistical explanations. The question of intensity aside, no-scale F-SU(5) can indeed provide a natural weakly interacting massive particle candidate with a mass in the correct range to yield gamma gamma and gamma Z emission lines at m(chi) similar to 133 GeV and m(chi) similar to 145 GeV, respectively. Additionally, we elucidate the emerging empirical connection between recent Planck satellite data and no-scale supergravity cosmological models which mimic the Starobinsky model of inflation. Together, these experiments furnish rich alternate avenues for testing no-scale F-SU(5), and similarly structured models, the results of which may lend independent credence to observations made at the Large Hadron Collider.