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Determine whether suppression by more than 10 dB can be produced and kept through acceleration and compression at wavelengths below $10^{-5}$ cm, which would reduce SASE start-up noise and microbunching gain.","problem_ref":"a06d57a97500fbb06bcd199f631f9064f9f7d863240b4d02135b5524eb129551","references":"","settled_by":"Measured coherent radiation from a beam below the shot-noise level at the stated wavelength after acceleration and compression.","status_note":"Sub-shot-noise density fluctuations were reported at optical wavelengths in the 2010s; suppression at XUV and x-ray wavelengths is undemonstrated.","title":"Suppressing electron-beam shot noise below the random 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