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DOE OSTI ยท 2587339

New physics contamination to precision luminosity measurements at future ๐‘’ +โข ๐‘’ โˆ’ colliders

Chiesa, MauroยทDel Pio, Clara L. (ORCID:0000000327388925)ยทMontagna, GuidoยทNicrosini, OresteยทPiccinini, FulvioยทUcci, Francesco P.
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Abstract

Several key observables of the high-precision physics program at future lepton colliders will critically depend on the knowledge of the absolute machine luminosity. The determination of the luminosity relies on the precise knowledge of some reference process, which is, in principle, not affected by unknown physics, so that its cross section can be computed within a well-established theory, like the Standard Model. Quantifying the uncertainties induced by possible new physics effects on such processes is, therefore, crucial. We present an investigation of light and heavy new physics contributions to the small-angle Bhabha process at future ๐‘’ + โข๐‘’ โˆ’ colliders, and we discuss possible strategies to remove the contamination due to heavy degrees of freedom by relying on observables that are independent of the absolute luminosity.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICSElectroweak interactionHypothetical particle physics modelsLepton-lepton interactionsPhenomenology

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Chiesa, Mauro, Del Pio, Clara L. (ORCID:0000000327388925), Montagna, Guido, Nicrosini, Oreste, Piccinini, Fulvio, Ucci, Francesco P.. 2025-07-28. New physics contamination to precision luminosity measurements at future ๐‘’ +โข ๐‘’ โˆ’ colliders. https://doi.org/10.1103/z4fk-52jy

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