Protons contain intrinsic charm quarks, a new study suggests

The massive quarks — counterintuitively heavier than the proton itself — might carry about 0.6 percent of a proton’s momentum.

Evidence at last that the proton has intrinsic charm

Protons Contain a Particle That's Heavier Than the Proton Itself

THE INTRINSIC CHARM OF THE PROTON

What Are Quarks? – World of Subatomic Particles – Evincism

Quarks charm on protons - Electrical e-Library.com

Universe, Free Full-Text

Protons contain intrinsic charm quarks, a new study suggests

Protons: Five of the biggest unanswered questions about the ubiquitous particle

PDF) Charm content of the proton: An analytic calculation

Do protons have intrinsic charm? New evidence suggests yes

Evidence at last that the proton has intrinsic charm