H. Siikonen

This paper introduces and applies a method for propagating changes in jet energy corrections into a D0 top quark mass measurement. It will serve as a source for the PRL presenting it's final results, and will be later published in a journal, or as a part of the author's PhD thesis. Motivation for the present measurement arises from the recalibration of the D0 flavor-dependent jet energy corrections. The recalibration was driven by the observation that the corrections for D0 Run IIb differ notably from those of Run IIa. The recalibration analysis was able to show that the Run IIb corrections should have resembled more those of Run IIa. The recalibrated jet energy corrections have an influence on the reconstructed top quarks through the jets that are produced in top quark decays. Hence, a change in the flavor-dependent jet energy corrections implies the need to revise the top mass measurement, performed by D0 in the lepton+jets channel. The D0 top mass average is almost completely determined by this measurement, and hence it has a direct impact on the top mass world average. A complete revision of the D0 top mass measurement is unlikely to occur, and hence this paper demonstrates the resulting top mass shift using a lighter methodology.

We review the possible effects of the miscalibration of the flavor-dependent Jet Energy Corrections ($F_{\mathrm{Corr}}$) on the DØ lepton+jets top mass measurement. The work is based on a previous study, where the DØ $F_{\mathrm{Corr}}$ calibration procedure was repeated based on the release of the internal DØ notes after a 5-year moratorium. The cited study was motivated by the extraordinary precision claimed by DØ in their top mass measurement. Using a Pythia6-based $F_{\mathrm{Corr}}$ recalibration, the $m_t$ result was shifted from 174.95 to 173.16 GeV. Moreover, utilizing a Herwig7-based $F_{\mathrm{Corr}}$ calibration (not accounted for in DØ studies), a shift down to 171.84 GeV was observed. We find this both convincing and specific evidence for re-reviewing a part of the $F_{\mathrm{Corr}}$ calibration process. However, DØ has been unwilling to open such studies or to provide other convincing counter-evidence.