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Describing hadronization via histories and observables for Monte-Carlo event reweighting

Bierlich, Christian LU ; Ilten, Phil ; Menzo, Tony ; Mrenna, Stephen ; Szewc, Manuel ; Wilkinson, Michael K. ; Youssef, Ahmed and Zupan, Jure (2025) In SciPost Physics 18(2).
Abstract

We introduce a novel method for extracting a fragmentation model directly from experimental data without requiring an explicit parametric form, called Histories and Observables for Monte-Carlo Event Reweighting (HOMER), consisting of three steps: the training of a classifier between simulation and data, the inference of single fragmentation weights, and the calculation of the weight for the full hadronization chain. We illustrate the use of HOMER on a simplified hadronization problem, a qq̄ string fragmenting into pions, and extract a modified Lund string fragmentation function f(z). We then demonstrate the use of HOMER on three types of experimental data: (i) binned distributions of high-level observables, (ii) unbinned event-by-event... (More)

We introduce a novel method for extracting a fragmentation model directly from experimental data without requiring an explicit parametric form, called Histories and Observables for Monte-Carlo Event Reweighting (HOMER), consisting of three steps: the training of a classifier between simulation and data, the inference of single fragmentation weights, and the calculation of the weight for the full hadronization chain. We illustrate the use of HOMER on a simplified hadronization problem, a qq̄ string fragmenting into pions, and extract a modified Lund string fragmentation function f(z). We then demonstrate the use of HOMER on three types of experimental data: (i) binned distributions of high-level observables, (ii) unbinned event-by-event distributions of these observables, and (iii) full particle cloud information. After demonstrating that f(z) can be extracted from data (the inverse of hadronization), we also show that, at least in this limited setup, the fidelity of the extracted f(z) suffers only limited loss when moving from (i) to (ii) to (iii). Public code is available at https://gitlab.com/uchep/mlhad.

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author
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organization
publishing date
type
Contribution to journal
publication status
published
subject
in
SciPost Physics
volume
18
issue
2
article number
054
publisher
SciPost
external identifiers
  • scopus:85218932554
ISSN
2542-4653
DOI
10.21468/SciPostPhys.18.2.054
language
English
LU publication?
yes
additional info
Publisher Copyright: Copyright C. Bierlich et al.
id
f1ef38c7-b214-4655-9032-692475fc76bf
date added to LUP
2025-06-23 13:10:50
date last changed
2025-06-23 13:11:52
@article{f1ef38c7-b214-4655-9032-692475fc76bf,
  abstract     = {{<p>We introduce a novel method for extracting a fragmentation model directly from experimental data without requiring an explicit parametric form, called Histories and Observables for Monte-Carlo Event Reweighting (HOMER), consisting of three steps: the training of a classifier between simulation and data, the inference of single fragmentation weights, and the calculation of the weight for the full hadronization chain. We illustrate the use of HOMER on a simplified hadronization problem, a qq̄ string fragmenting into pions, and extract a modified Lund string fragmentation function f(z). We then demonstrate the use of HOMER on three types of experimental data: (i) binned distributions of high-level observables, (ii) unbinned event-by-event distributions of these observables, and (iii) full particle cloud information. After demonstrating that f(z) can be extracted from data (the inverse of hadronization), we also show that, at least in this limited setup, the fidelity of the extracted f(z) suffers only limited loss when moving from (i) to (ii) to (iii). Public code is available at https://gitlab.com/uchep/mlhad.</p>}},
  author       = {{Bierlich, Christian and Ilten, Phil and Menzo, Tony and Mrenna, Stephen and Szewc, Manuel and Wilkinson, Michael K. and Youssef, Ahmed and Zupan, Jure}},
  issn         = {{2542-4653}},
  language     = {{eng}},
  number       = {{2}},
  publisher    = {{SciPost}},
  series       = {{SciPost Physics}},
  title        = {{Describing hadronization via histories and observables for Monte-Carlo event reweighting}},
  url          = {{http://dx.doi.org/10.21468/SciPostPhys.18.2.054}},
  doi          = {{10.21468/SciPostPhys.18.2.054}},
  volume       = {{18}},
  year         = {{2025}},
}