What the study found
The study finds that Higgs-boson-mediated production of dark quarks at the Future Circular Collider in electron-positron collisions could produce semi-visible jets, meaning jets made of both visible and invisible particles. The authors report that a graph neural network jet tagger helps improve sensitivity, especially when the invisible part of the signal is small.
Why the authors say this matters
The authors conclude that their strategy can improve discovery prospects for Higgs boson-induced semi-visible jets at the Future Circular Collider. They also state that the approach can probe a wide parameter space for the models considered and constrain Higgs boson exotic branching ratios into dark quarks at the permille level, meaning at about one part in a thousand.
What the researchers tested
The researchers studied exotic signatures from confining dark sectors in electron-positron collisions at the Future Circular Collider. They assumed the Higgs boson mediates the interaction between the Standard Model and the dark sector, then examined semi-visible jet final states with different invisible fractions, including cases enriched in leptons and photons.
What worked and what didn't
When the invisible component was large, selections based on kinematic features such as missing energy provided good signal-to-background discrimination. When the invisible fraction was smaller, the reduced missing energy made the signals more similar to Standard Model events, and a graph neural network jet tagger based on jet substructure was used instead; this improved sensitivity. The abstract does not report detailed numerical performance comparisons beyond these statements.
What to keep in mind
The summary is limited to the models and signatures considered in the abstract. The abstract does not describe detector effects, background systematics, or other limitations in detail.
Key points
- The study examines Higgs-boson-mediated production of dark quarks in electron-positron collisions at the Future Circular Collider.
- The expected signal is a semi-visible jet, containing both visible and invisible particles.
- Large invisible fractions are better handled with missing-energy-based selections.
- Smaller invisible fractions are better separated using a graph neural network jet tagger based on jet substructure.
- The authors say the strategy could constrain exotic Higgs branching ratios into dark quarks at the permille level.
Disclosure
- Research title:
- Semi-visible dark jets may be probed at FCC-ee
- Authors:
- Cesare Cazzaniga, Annapaola de Cosa, Felix Kahlhoefer, Andrea S. Maria, Roberto Seidita, Emre Sitti
- Institutions:
- ETH Zurich, Karlsruhe Institute of Technology, University of Zurich, Prediction Systems (United States)
- Publication date:
- 2026-04-28
- OpenAlex record:
- View
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