Unparticle effects at the MUonE experiment

• Published in: The European physical journal. C, Particles and fields Particles and fields, 2023-11, Vol.83 (11), p.1037-10, Article 1037
• Main Authors: Le, Duc Ninh, Le, Van Dung, Le, Duc Truyen, Le, Van Cuong
• Format: Article
• Language: English
• Subjects: Astronomy; Astrophysics and Cosmology; Cosmology; Couplings; Elementary Particles; Energy; Experiments; Hadrons; Heavy Ions; Invariance; Leptons; Measurement Science and Instrumentation; Nuclear Energy; Nuclear Physics; Physics; Physics and Astronomy; Quantum Field Theories; Quantum Field Theory; Quarks; Regular Article - Theoretical Physics; Scale invariance; String Theory; Theoretical physics
• ISSN: 1434-6052; 1434-6044; 1434-6052
• DOI: 10.1140/epjc/s10052-023-12213-3

We investigate possible effects of unparticles at the MUonE experiment by considering a general model for unparticle with broken scale invariance, characterized by the scaling dimension d and the energy scale μ at which the scale invariance is broken. Taking into account available relevant constraints on the couplings of the unparticles with the Standard Model (SM) leptons, we found that the MUonE experiment at the level of 10 ppm systematic accuracy is sensitive to such effects if 1 < d ≲ 1.4 and 1 ≤ μ ≲ 12 GeV for vector unparticles. The effects of scalar unparticles are too feeble to be detected. The vector unparticles can induce a significant shift on the best-fit value of a μ had at the MUonE, thereby providing an opportunity to detect unparticles or to obtain a new bound on the unparticle-SM couplings in the case of no anomaly.