Modifications of QCD splitting in QGP

In ultra-relativistic heavy-ion collisions, the quark-gluon plasma (QGP) significantly alters the behavior of quarks and gluons. Using the Baier-Dokshitzer-Mueller-Peigné-Schiff and Zakharov (BDMPS-Z) formalism, we explored how the QGP modifies gluon splitting into quark-antiquark pairs, with a focus on charm quarks. Our study introduces a compact framework to account for repeated interactions between the splitting particles and the medium (Attems et al., 2023; Attems et al., 2024). Two key effects emerge:

Momentum Broadening – The quark-antiquark pairs gain relative momentum from the medium, increasing their invariant mass.
Enhanced Production – The medium boosts the production of such pairs, especially when the momentum transfer is comparable to the quark mass.

These effects are particularly significant for charm quarks in heavy-ion collisions, as seen in ccbar production. Interestingly, the same QCD formalism that explains jet suppression also predicts enhanced production of cbar pairs in jets, a phenomenon measurable through D⁰-tagged jets. This work highlights how the QGP modifies fundamental processes in QCD, offering a new avenue for probing the medium’s properties.

References

2024

Phys. Rev. Lett.

Medium-Enhanced c\barc Radiation

Maximilian Attems, Jasmine Brewer, Gian Michele Innocenti, and 5 more authors

Phys. Rev. Lett., 2024

DOI arXiv Cite

@article{Attems:2022otp,
  author = {Attems, Maximilian and Brewer, Jasmine and Innocenti, Gian Michele and Mazeliauskas, Aleksas and Park, Sohyun and van der Schee, Wilke and Soyez, Gregory and Wiedemann, Urs Achim},
  title = {{Medium-Enhanced $c\bar{c}$ Radiation}},
  archiveprefix = {arXiv},
  primaryclass = {hep-ph},
  reportnumber = {CERN-TH-2022-046},
  doi = {10.1103/PhysRevLett.132.212301},
  journal = {Phys. Rev. Lett.},
  volume = {132},
  number = {21},
  pages = {212301},
  year = {2024}
}

2023

JHEP

The medium-modified g\to c\overlinec splitting function in the BDMPS-Z formalism

Maximilian Attems, Jasmine Brewer, Gian Michele Innocenti, and 4 more authors

JHEP, 2023

DOI arXiv Cite

@article{Attems:2022ubu,
  author = {Attems, Maximilian and Brewer, Jasmine and Innocenti, Gian Michele and Mazeliauskas, Aleksas and Park, Sohyun and van der Schee, Wilke and Wiedemann, Urs Achim},
  title = {{The medium-modified $ g\to c\overline{c} $ splitting function in the BDMPS-Z formalism}},
  archiveprefix = {arXiv},
  primaryclass = {hep-ph},
  reportnumber = {CERN-TH-2022-045},
  doi = {10.1007/JHEP01(2023)080},
  journal = {JHEP},
  volume = {01},
  pages = {080},
  year = {2023}
}