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DOE OSTI · 1354708

Gravity localization on hybrid branes

Veras, D. F.S.·Cruz, W. T.·Maluf, R. V.·Almeida, C. A.S.
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Abstract

The NA60 experiment studied low-mass muon pair production in proton–nucleus (p–A) collisions using a 400 GeV proton beam at the CERN SPS. The low-mass dimuon spectrum is well described by the superposition of the two-body and Dalitz decays of the light neutral mesons η, ρ, ω, η' and φ, and no evidence of in-medium effects is found. A new high-precision measurement of the electromagnetic transition form factors of the η and ω was performed, profiting from a 10 times larger data sample than the peripheral In–In sample previously collected by NA60. Using the pole-parameterisation |F(M)| 2 =(1 - M 2 /Λ 2 ) -2 we find Λ -2 η = 1.934 ± 0.067 (stat.) ±0.050(syst.) (GeV/c 2 ) -2 and Λ -2 ω = 2.223 ± 0.026(stat.) ± 0.037(syst.) (GeV/c 2 ) -2 . An improved value of the branching ratio of the Dalitz decay ω → μ + μ - π 0 is also obtained, with BR(ω → μ + μ - π 0 ) = [1.41 ± 0.09(stat.) ± 0.15(syst.)] ×10 -4 . Finally, further results refer to the ρ line shape and a new limit on ρ/ω interference in hadron interactions.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS

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Veras, D. F.S., Cruz, W. T., Maluf, R. V., Almeida, C. A.S.. 2016-03-01. Gravity localization on hybrid branes. https://doi.org/10.1016/j.physletb.2016.01.013

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