arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 0812.1042hep-phhep-ex
收藏

\sqrt{s}_m in:用于确定强子对撞机能量缺失事件中新物理学质量标度的全局包容变量

\sqrt{s}_min: a global inclusive variable for determining the mass scale of new physics in events with missing energy at hadron colliders

Partha Konar, Kyoungchul Kong, Konstantin T. Matchev

摘要:

我们提出了一个新的全球性和完全包容的变量\sqrt{s}_{min},用于确定在强子对撞机上丢失能量的事件中新粒子的质量尺度。我们定义\sqrt{s}_{min}为与测得的总能量E和总可见动量\vec{P}一致的最小质心部分子能级能量。我们证明了对于任意事件,\sqrt{s}_{min}简单地由公式\sqrt{s}_{min} = \sqrt{E^2-P_z^2} + \sqrt{\met^2+M_{inv}^2}给出,其中M_{inv}是事件中产生的所有不可见粒子的总质量。我们使用t \bar{t}生产和几个超对称的例子来论证,在\sqrt{s}_{min}分布的峰值与事件中最初产生的母粒子的质量阈值相关。这个猜想允许一个确定的重超伙伴质量规模(作为LSP质量的函数)在一个完全通用的和模型独立的方式,而不需要任何独家事件重建。在我们的几个多射流和丢失能量信号的超对称性例子中,基于\sqrt{s}_{min}的质量测量的准确度通常在百分比水平,并且不会差于10%。在考虑初态辐射和多部分子相互作用的影响后,计算精度有所下降,但对重超对称质谱仍保持在10%左右。

英文摘要:

We propose a new global and fully inclusive variable \sqrt{s}_{min} for determining the mass scale of new particles in events with missing energy at hadron colliders. We define \sqrt{s}_{min} as the minimum center-of-mass parton level energy consistent with the measured values of the total calorimeter energy E and the total visible momentum \vec{P}. We prove that for an arbitrary event, \sqrt{s}_{min} is simply given by the formula \sqrt{s}_{min}=\sqrt{E^2-P_z^2}+\sqrt{\met^2+M_{inv}^2}, where M_{inv} is the total mass of all invisible particles produced in the event. We use t\bar{t} production and several supersymmetry examples to argue that the peak in the \sqrt{s}_{min} distribution is correlated with the mass threshold of the parent particles originally produced in the event. This conjecture allows a determination of the heavy superpartner mass scale (as a function of the LSP mass) in a completely general and model-independent way, and without the need for any exclusive event reconstruction. In our SUSY examples of several multijet plus missing energy signals, the accuracy of the mass measurement based on \sqrt{s}_{min} is typically at the percent level, and never worse than 10%. After including the effects of initial state radiation and multiple parton interactions, the precision gets worse, but for heavy SUSY mass spectra remains 10%.

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。

↑