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Inclusive Higgsstrahlung cross section measurements with the new reference sample method

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 نشر من قبل Jonas Kunath
 تاريخ النشر 2020
  مجال البحث
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An accurate determination of the Higgsstrahlung cross section is one of the main objectives at a future electron-positron collider. It allows for the only Higgs boson decay model independent measurement of the total Higgs width. Current results use the recoil mass shape method. That technique can be applied to Higgsstrahlung events with Z boson decays into muons, into electrons and, with reservations, into quarks. The samples built from Higgsstrahlung events with Z boson decays into taus and neutrinos are not used in previous analyses. We present here a new method, the reference sample method. It extends the recoil mass method to be usable with the tau and neutrino samples as well. The extension promises a model independent determination of the inclusive Higgsstrahlung cross section with a 2.1-2.2% uncertainty from each of the two ILC polarization scenarios at $sqrt{s}$=250 GeV with an integrated luminosity of 250 $mathrm{fb^{-1}}$. This represents an improvement of 20-30% on the accuracy from the application of the new approach without additional data collection.

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