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Accepted · first revision · record

Title: Nuclear modification of gluons at large momentum fraction
Plain: The EMC effect was seen for quarks, but gluons inside nuclei may also be modified. Present data barely constrain gluons carrying more than 10 percent of a nucleon's momentum.
Precise: Determine the ratio $g_A(x, Q^{2})/g_N(x, Q^{2})$ of the gluon distribution per nucleon in heavy nuclei to that in free nucleons for $0.1 < x < 0.6$ at $Q^{2} = 10\,\mathrm{GeV}^{2}$ with uncertainty below 10 percent. Answer: presence and size of a gluon EMC effect.
Settled by: EIC measurements of charm production and the longitudinal structure function $F_{L}$ in electron-nucleus collisions, entered in nuclear parton-distribution fits.
Kind: well-posed
Answer type: value
References: (empty)
Literature status: open
Status note: (empty)
Posed since: (empty)