What the study found
The study found that a Transformer classifier can identify a class of jets in nucleus-nucleus collisions that have been unequivocally modified. It also found a robust estimate of the upper bound for the fraction of jets in nucleus-nucleus collisions that are indistinguishable from those produced in proton-proton collisions.
Why the authors say this matters
The authors say this matters because vacuum-like jets, meaning jets that experienced little interaction with the quark gluon plasma, dilute the overall observed modification in nucleus-nucleus samples. The study suggests that being able to judge jet modification on a jet-by-jet basis would help overcome this limitation and support the study of the underlying physical mechanisms.
What the researchers tested
The researchers tested a Transformer classifier trained on a low-level representation of jets using the 4-momenta, meaning the energy and motion information, of all jet constituents. They compared this approach with other architectures that use high-level physical observables as input.
What worked and what didn't
The Transformer was able to capture discriminating information not accessible to other architectures using high-level observables. It identified a class of jets as unequivocally modified in the experimentally relevant case where both medium response and underlying event contamination were accounted for.
What to keep in mind
The abstract does not describe detailed numerical results in the provided summary. It also does not state additional limitations beyond the scope covered here.
Key points
- A Transformer classifier identified a class of jets in nucleus-nucleus collisions as unequivocally modified.
- The study estimated an upper bound on the fraction of jets in nucleus-nucleus collisions that are indistinguishable from proton-proton jets.
- The model used low-level jet constituent 4-momenta rather than only high-level physical observables.
- The Transformer found discriminating information that other tested architectures did not access.
- The experimentally relevant case included both medium response and underlying event contamination.
Disclosure
- Research title:
- Transformer identifies heavily modified jets in heavy-ion collisions
- Authors:
- Miguel Crispim Romão, João A. Gonçalves, José Guilherme Milhano
- Institutions:
- Durham University, University of Lisbon
- Publication date:
- 2026-04-27
- OpenAlex record:
- View
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