论文标题
希格斯玻色子宽度的测量及其对ZZ生产的脱壳贡献的证据
Measurement of the Higgs boson width and evidence of its off-shell contributions to ZZ production
论文作者
论文摘要
自2012年发现希格斯玻色子以来，对其性质的详细研究一直在进行。除了其质量外，它的宽度与寿命有关 - 是一个重要的参数。确定该数量的一种方法是测量其非壳产量，其中希格斯玻色子质量远离其名义值，并将其与质量接近名义值的壳产量相关。在这里，我们报告了对两个Z玻色子的生产横截面的这种非壳贡献的证据，并在CERN大型强子对撞机的CMS实验中进行了数据。我们将离壳Higgs玻色子的总率限制在Z玻色子对生产阈值之外，相对于其标准模型预期，在95％的置信度下[0.0061，2.0]的间隔[0.0061，2.0]。没有外壳贡献的情况不包括0.0003的$ P $值（3.6标准偏差）。我们将希格斯玻色子的宽度作为$γ_ {\ mathrm {h}} $ = 3.2 $ = 3.2 $ _ { - 1.7}^{+2.4} $ MEV，与标准模型预期4.1 MEV一致。此外，我们对W和Z玻色子对的异常希格斯玻色子耦合设置了约束。
Since the discovery of the Higgs boson in 2012, detailed studies of its properties have been ongoing. Besides its mass, its width - related to its lifetime - is an important parameter. One way to determine this quantity is by measuring its off-shell production, where the Higgs boson mass is far away from its nominal value, and relating it to its on-shell production, where the mass is close to the nominal value. Here, we report evidence for such off-shell contributions to the production cross section of two Z bosons with data from the CMS experiment at the CERN Large Hadron Collider. We constrain the total rate of the off-shell Higgs boson contribution beyond the Z boson pair production threshold, relative to its standard model expectation, to the interval [0.0061, 2.0] at 95% confidence level. The scenario with no off-shell contribution is excluded at a $p$-value of 0.0003 (3.6 standard deviations). We measure the width of the Higgs boson as $Γ_{\mathrm{H}}$ = 3.2 $_{-1.7}^{+2.4}$ MeV, in agreement with the standard model expectation of 4.1 MeV. In addition, we set constraints on anomalous Higgs boson couplings to W and Z boson pairs.
