---
_id: '14753'
abstract:
- lang: eng
  text: "Several fixed-target experiments reported J/ψ and ϒ polarizations, as functions
    of Feynman x (xF) and transverse momentum (PT), in three different frames, using
    different combinations of beam particles, target nuclei, and collision energies.
    Despite the diverse and heterogeneous picture formed by these measurements, a
    detailed look allows us to discern qualitative physical patterns that inspire
    a simple empirical model. This data-driven scenario offers a good quantitative
    description of the J/ψ and ϒ(1S) polarizations measured in proton- and pion-nucleus
    collisions, in the xF 0.5 domain: more than 80 data points (not statistically
    independent) are well reproduced with only one free parameter. This study sets
    the context for future low-PT\r\n quarkonium polarization measurements in proton-
    and pion-nucleus collisions, such as those to be made by the AMBER experiment,
    and shows that such measurements provide significant constraints on the poorly-known
    parton distribution functions of the pion."
acknowledgement: "P.F. and C.L. acknowledge support from Fundação para a Ciência e
  a Tecnologia, Portugal, under contract CERN/FIS-PAR/0010/2019.\r\nOpen Access funded
  by SCOAP3."
article_number: '137871'
article_processing_charge: Yes (via OA deal)
article_type: original
author:
- first_name: Pietro
  full_name: Faccioli, Pietro
  last_name: Faccioli
- first_name: Ilse
  full_name: Krätschmer, Ilse
  id: 30d4014e-7753-11eb-b44b-db6d61112e73
  last_name: Krätschmer
  orcid: 0000-0002-5636-9259
- first_name: Carlos
  full_name: Lourenço, Carlos
  last_name: Lourenço
citation:
  ama: 'Faccioli P, Krätschmer I, Lourenço C. Low-pT quarkonium polarization measurements:
    Challenges and opportunities. <i>Physics Letters B</i>. 2023;840. doi:<a href="https://doi.org/10.1016/j.physletb.2023.137871">10.1016/j.physletb.2023.137871</a>'
  apa: 'Faccioli, P., Krätschmer, I., &#38; Lourenço, C. (2023). Low-pT quarkonium
    polarization measurements: Challenges and opportunities. <i>Physics Letters B</i>.
    Elsevier. <a href="https://doi.org/10.1016/j.physletb.2023.137871">https://doi.org/10.1016/j.physletb.2023.137871</a>'
  chicago: 'Faccioli, Pietro, Ilse Krätschmer, and Carlos Lourenço. “Low-PT Quarkonium
    Polarization Measurements: Challenges and Opportunities.” <i>Physics Letters B</i>.
    Elsevier, 2023. <a href="https://doi.org/10.1016/j.physletb.2023.137871">https://doi.org/10.1016/j.physletb.2023.137871</a>.'
  ieee: 'P. Faccioli, I. Krätschmer, and C. Lourenço, “Low-pT quarkonium polarization
    measurements: Challenges and opportunities,” <i>Physics Letters B</i>, vol. 840.
    Elsevier, 2023.'
  ista: 'Faccioli P, Krätschmer I, Lourenço C. 2023. Low-pT quarkonium polarization
    measurements: Challenges and opportunities. Physics Letters B. 840, 137871.'
  mla: 'Faccioli, Pietro, et al. “Low-PT Quarkonium Polarization Measurements: Challenges
    and Opportunities.” <i>Physics Letters B</i>, vol. 840, 137871, Elsevier, 2023,
    doi:<a href="https://doi.org/10.1016/j.physletb.2023.137871">10.1016/j.physletb.2023.137871</a>.'
  short: P. Faccioli, I. Krätschmer, C. Lourenço, Physics Letters B 840 (2023).
date_created: 2024-01-08T13:09:17Z
date_published: 2023-05-10T00:00:00Z
date_updated: 2025-09-09T14:13:46Z
day: '10'
ddc:
- '530'
department:
- _id: MaRo
doi: 10.1016/j.physletb.2023.137871
external_id:
  isi:
  - '000967947300001'
file:
- access_level: open_access
  checksum: 02dec160dbc81d95985e755869d8afbf
  content_type: application/pdf
  creator: dernst
  date_created: 2024-01-09T08:59:24Z
  date_updated: 2024-01-09T08:59:24Z
  file_id: '14762'
  file_name: 2023_PhysicsLettersB_Faccioli.pdf
  file_size: 855494
  relation: main_file
  success: 1
file_date_updated: 2024-01-09T08:59:24Z
has_accepted_license: '1'
intvolume: '       840'
isi: 1
keyword:
- Nuclear and High Energy Physics
language:
- iso: eng
license: https://creativecommons.org/licenses/by/4.0/
month: '05'
oa: 1
oa_version: Published Version
publication: Physics Letters B
publication_identifier:
  eissn:
  - 1873-2445
  issn:
  - 0370-2693
publication_status: published
publisher: Elsevier
quality_controlled: '1'
scopus_import: '1'
status: public
title: 'Low-pT quarkonium polarization measurements: Challenges and opportunities'
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: journal_article
user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345
volume: 840
year: '2023'
...