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DOE OSTI · 2538618

Characterizing the hadronization of parton showers using the HOMER method

Assi, Benoît [Univ. of Cincinnati, OH (United States)] (ORCID:0000000309243335)·Bierlich, Christian [Lund Univ. (Sweden)] (ORCID:0000000239786085)·Ilten, Philip [Univ. of Cincinnati, OH (United States)] (ORCID:0000000155341732)·Menzo, Tony [Univ. of Cincinnati, OH (United States)] (ORCID:0000000220134570)·Mrenna, Stephen [Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States); Univ. of Cincinnati, OH (United States)] (ORCID:000000018731160X)·Szewc, Manuel [Univ. of Cincinnati, OH (United States); International Center for Advanced Studies (ICAS) (ICIFI-ECyT-UNSAM), Buenos Aires (Argentina)] (ORCID:0000000230145388)·Wilkinson, Michael K. [Univ. of Cincinnati, OH (United States)] (ORCID:0000000165612145)·Youssef, Ahmed [Univ. of Cincinnati, OH (United States)] (ORCID:0000000315854757)·Zupan, Jure [Univ. of Cincinnati, OH (United States)] (ORCID:000000019445537X)
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Abstract

We update the HOMER method, a technique to solve a restricted version of the inverse problem of hadronization – extracting the Lund string fragmentation function f(z) from data using only observable information. Here, we demonstrate its utility by extracting f(z) from synthetic Pythia simulations using high-level observables constructed on an event-by-event basis, such as multiplicities and shape variables. Four cases of increasing complexity are considered, corresponding to e + e − collisions at a center-of-mass energy of 90 ≥ v producing either a string stretched between a $q$ and $\bar{q}$ containing no gluons; the same string containing one gluon g with fixed kinematics; the same but the gluon has varying kinematics; and the most realistic case, strings with an unrestricted number of gluons that is the end-result of a parton shower. We demonstrate the extraction of f(z) in each case, with the result of only a relatively modest degradation in performance of the HOMER method with the increased complexity of the string system.

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Assi, Benoît [Univ. of Cincinnati, OH (United States)] (ORCID:0000000309243335), Bierlich, Christian [Lund Univ. (Sweden)] (ORCID:0000000239786085), Ilten, Philip [Univ. of Cincinnati, OH (United States)] (ORCID:0000000155341732), Menzo, Tony [Univ. of Cincinnati, OH (United States)] (ORCID:0000000220134570), Mrenna, Stephen [Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States); Univ. of Cincinnati, OH (United States)] (ORCID:000000018731160X), Szewc, Manuel [Univ. of Cincinnati, OH (United States); International Center for Advanced Studies (ICAS) (ICIFI-ECyT-UNSAM), Buenos Aires (Argentina)] (ORCID:0000000230145388), Wilkinson, Michael K. [Univ. of Cincinnati, OH (United States)] (ORCID:0000000165612145), Youssef, Ahmed [Univ. of Cincinnati, OH (United States)] (ORCID:0000000315854757), Zupan, Jure [Univ. of Cincinnati, OH (United States)] (ORCID:000000019445537X). 2025-11-11. Characterizing the hadronization of parton showers using the HOMER method. https://doi.org/10.21468/scipostphys.19.5.125

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