Transverse spin asymmetries and the electron Yukawa coupling at an FCC-ee

Journal Article · 22 October 2024 · Physical Review. D.

DOI: https://doi.org/10.1103/physrevd.110.075026 · OSTI ID:2473301

Boughezal, Radja  ^[1]; Petriello, Frank ^[2]; Şimşek, Kağan  ^[3]

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1. Argonne National Laboratory (ANL), Argonne, IL (United States)
2. Argonne National Laboratory (ANL), Argonne, IL (United States); Northwestern Univ., Evanston, IL (United States)
3. Northwestern Univ., Evanston, IL (United States)

We show that measurements of single transverse-spin asymmetries at an 𝑒⁺⁢𝑒⁻ collider can enhance the sensitivity to the electron Yukawa coupling, possibly enabling observation of the Standard Model value for this quantity. We demonstrate that the significance in both the 𝑏⁢$$\overline{𝑏}$$ and semileptonic 𝑊⁢𝑊 final states can be enhanced by factors of up to 3 compared to inclusive cross-section determinations of this coupling for transversely polarized electrons. If the positrons can be simultaneously longitudinally polarized, even at the level of 30%, the significance can be enhanced by a factor of 5 or more. The method utilizes quantum interference between the Higgs signal and the continuum background and is also applicable in other 𝑊⁢𝑊 and 𝑍⁢𝑍 final states.

• Research Organization: Argonne National Laboratory (ANL), Argonne, IL (United States)
• Sponsoring Organization: USDOE; USDOE Office of Science (SC), High Energy Physics (HEP)
• Grant/Contract Number: AC02-06CH11357; FG02-91ER40684
• OSTI ID: 2473301
• Journal Information: Physical Review. D., Journal Name: Physical Review. D. Journal Issue: 7 Vol. 110; ISSN 2470-0010; ISSN 2470-0029
• Publisher: American Physical Society (APS)Copyright Statement
• Country of Publication: United States
• Language: English