AI 中文总结
研究大 Bjorken-$x$ 处 PDFs 受新物理影响问题，通过在 SMEFT 风险评估场景中，比较排除能量截断数据的保守拟合与用 {\tt SIMUnet} 工具同时拟合 PDFs 和威尔逊系数这两种策略，成功恢复被 PDFs 吸收隐藏的新物理。
AI 中文摘要
大 Bjorken-$x$ 处的部分子分布函数（PDFs）主要受高能测量约束。若未计入的新物理（NP）存在于全球 PDF 拟合中强子对撞机可观测量的高能尾部，可能吸收能量增长效应。我们在影响高亮度 LHC 上高质量 Drell-Yan 产生的标准模型有效场论（SMEFT）风险评估场景中说明了这种效应，并比较了两种获得稳健 PDFs 和 SMEFT 边界的策略：排除高于能量截断数据的保守拟合，以及使用 {\tt SIMUnet} 工具对 PDFs 和威尔逊系数进行同时拟合。两种方法都成功恢复了原本被 PDFs 吸收和隐藏的注入新物理。
英文摘要
Parton Distribution Functions (PDFs) at large Bjorken-$x$ are mostly constrained by high-energy measurements, and thus risk to absorb the energy-growing effects of unaccounted new physics (NP) if it were present in the high-energy tails of hadron-collider observables used in global PDF fits. If undetected, such contamination biases the resulting PDFs and can potentially hide the absorbed NP signals from subsequent searches. We illustrate this effect in a Standard Model Effective Field Theory (SMEFT) risk-assessment scenario affecting high-mass Drell-Yan production at the High-Luminosity LHC, and compare two strategies to obtain robust PDFs and SMEFT bounds: conservative fits that exclude data above an energy cut, and simultaneous fits of PDFs and Wilson coefficients performed with the {\tt SIMUnet} tool. Both approaches are shown to successfully recover the injected new physics that is otherwise absorbed and hidden by the PDFs.
CommentsContribution to 37th Rencontres de Blois
