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تسجيل مستخدم جديدImpact of a light stabilized radion in supernovae cooling
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In the Randall-Sundrum model where the Standard Model fields are confined to the TeV brane located at the orbifold point $theta = pi$ and the gravity peaks at the Planck brane located at $theta = 0$, the stabilized modulus (radion) field is required to stabilize the size of the fifth spatial dimension. It can be produced copiously inside the supernova core due to nucleon-nucleon bremstrahlung, electron-positron and plasmon-plasmon annihilations, which then subsequently decays to neutrino-antineutrino pair and take away the energy released in SN1987A explosion. Assuming that the supernovae cooling rate $dot{varepsilon} le 7.288times 10^{-27} rm{GeV}$, we find the lower bound on the radion vev $vphi sim 9.0$ TeV, 2.2 TeV and 0.9 TeV corresponding to the radion mass $m_phi = 5$ GeV, 20 GeV and 50 GeV, respectively.
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