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First measurement of protons charge form factor at very low $Q^2$ with initial state radiation

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 نشر من قبل Harald Merkel
 تاريخ النشر 2016
  مجال البحث
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We report on a new experimental method based on initial-state radiation (ISR) in e-p scattering, in which the radiative tail of the elastic e-p peak contains information on the proton charge form factor ($G_E^p$) at extremely small $Q^2$. The ISR technique was validated in a dedicated experiment using the spectrometers of the A1-Collaboration at the Mainz Microtron (MAMI). This provided first measurements of $G_E^p$ for $0.001leq Q^2leq 0.004 (GeV/c)^2$.



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