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arXiv 0706.3155hep-phhep-th
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非粒子物理的对撞机唯象学

Collider Phenomenology of Unparticle Physics

Kingman Cheung, Wai-Yee Keung, Tzu-Chiang Yuan

摘要:

本文研究了正负电子和强子对撞机中与精确标度不变扇区相关的非粒子物理的低能现象,该扇区在高能标度下具有非平凡的红外不动点。给出了自旋为0、1或2的非粒子耦合到各种标准模型规范不变算符的Feynman规则,这些规范不变算符与许多涉及非粒子实发射或虚传播子效应的低能过程有关。本文研究了在LEP 2和ILC条件下,非粒子与光子或$Z$玻色子一起产生以及$Z$衰变为非粒子加费米子-反费米子对过程中,非粒子的丢失能量和/或反冲质量分布。研究了强子碰撞中单喷流的产生。详细研究了Drell-Yan过程以及电子正电子湮没中μ子对和双光子产生的非粒子传播子中的复相位,它可以引起非粒子交换图和标准模型振幅之间的有趣干涉效应.这些能量和/或反冲质量分布(除了在强子对撞机)和干涉效应被发现敏感地不仅依赖于尺度尺寸,但也对自旋的unparticle。对于自旋为2的非粒子,它的物理效应被发现类似于卡鲁扎-克莱因引力子的塔,这强烈表明潜在的非粒子物理学可能源于更高维的理论。推测了非粒子物理学和大额外维理论之间的联系。从LEP 2单光子产生数据和4-费米子接触相互作用中推导出非粒子尺度的实验约束。

英文摘要:

Low energy phenomenology of the unparticle physics associated with an exact scale invariant sector possessing a non-trivial infrared fixed point at a higher energy scale is explored for both electron-positron and hadronic colliders. Feynman rules for a spin 0, 1 or 2 unparticle coupled to a variety of standard model gauge invariant operators that are relevant to many low energy processes involving either real emissions of unparticles or their virtual propagator effects are presented. Missing energy and/or recoil mass distributions of the unparticle in the associated production of unparticle together with a photon or $Z$ boson at LEP2 and ILC as well as in $Z$ decay into an unparticle plus a fermion-antifermion pair are studied. Monojet production at hadronic collisions is explored. The complex phase in the unparticle propagator that can give rise to interesting interference effects between an unparticle exchange diagram and the standard model amplitudes are studied in details for the Drell-Yan process as well as muon pair and diphoton production in electron-positron annihilation. These energy and/or recoil mass distributions (with the exception in hadron colliders) and interference effects are found sensitively depending not only on the scale dimension but also on the spin of the unparticle. For the spin-2 unparticle, its physical effects is found to resemble that of a tower of Kaluza-Klein gravitons, which strongly indicates that the underlying unparticle physics may have root in a higher dimensional theory. A connection between unparticle physics and theories of large extra dimension is speculated. Experimental constraints on the unparticle scale are deduced from the LEP2 data on mono-photon production and from the 4-fermion contact interactions.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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