SLAC National Accelerator Laboratory, Stanford University, Stanford, California 94309, USA.
Phys Rev Lett. 2013 Sep 13;111(11):111802. doi: 10.1103/PhysRevLett.111.111802.
We study the change in the diphoton-invariant-mass distribution for Higgs boson decays to two photons, due to interference between the Higgs resonance in gluon fusion and the continuum background amplitude for gg→γγ. Previously, the apparent Higgs mass was found to shift by around 100 MeV in the standard model in the leading-order approximation, which may potentially be experimentally observable. We compute the next-to-leading-order QCD corrections to the apparent mass shift, which reduce it by about 40%. The apparent mass shift may provide a way to measure, or at least bound, the Higgs boson width at the Large Hadron Collider through "interferometry." We investigate how the shift depends on the Higgs width, in a model that maintains constant Higgs boson signal yields. At Higgs widths above 30 MeV, the mass shift is over 200 MeV and increases with the square root of the width. The apparent mass shift could be measured by comparing with the ZZ* channel, where the shift is much smaller. It might be possible to measure the shift more accurately by exploiting its strong dependence on the Higgs transverse momentum.
我们研究了由于胶子融合中的希格斯共振与 gg→γγ 连续背景幅度之间的干涉，导致双光子不变质量分布中希格斯玻色子衰变的变化。此前，在标准模型的领头阶近似中，我们发现表观希格斯质量的移动约为 100 MeV，这可能在实验上是可观测的。我们计算了对表观质量移动的次领头阶 QCD 修正，它将其降低了约 40%。表观质量移动可能提供了一种通过“干涉”在大型强子对撞机上测量（或至少限制）希格斯玻色子宽度的方法。我们研究了在保持希格斯玻色子信号产额不变的模型中，这种移动如何取决于希格斯宽度。在希格斯宽度高于 30 MeV 时，质量移动超过 200 MeV，并且随宽度的平方根增加。通过与 ZZ* 通道进行比较，可以测量表观质量移动，其中移动要小得多。通过利用其对希格斯横动量的强烈依赖关系，可以更准确地测量这种移动。
