The recoil momentum spectrum from the decay $B^+ \to K^+ +\mathrm{anything}$ has recently been measured by the BaBar collaboration. The spectrum has a peak with invariant mass near the mass of the $X(3872)$ meson. The preliminary measurement by the BaBar collaboration implies that its branching fraction into $J/ψ\, π^+π^-$ is about 4\%. We emphasize that this is the branching fraction for the entire resonance feature from $B^+$-to-$K^+$ transitions, which includes a $D^{*0} \bar D^0$ and $D^0 \bar D^{*0}$ threshold enhancement as well as a possible bound state below the threshold or a virtual state. If the $X$ is a bound state of charm mesons, its branching fraction into $J/ψ\, π^+π^-$ should be considerably larger than that of the $X$ resonance feature. We use measurements of branching ratios of the $X$ to put an upper bound on this branching fraction of 33\%. We also constrain the parameters of the simplest plausible model for the line shapes of the $X$ using the precise measurement of the resonance energy of the $X$ and an estimate of the branching fraction into $D^0 \bar D^0 π^0$ and $D^0 \bar D^0γ$ from the $X$ resonance feature from $B^+$-to-$K^+$ transitions.
Some comments on $\bar n p$-annihilation branching ratios into $ππ$-, $\bar K K$- and $πη$-channels
我们给出了一些意见$\bar n p$ -部分分支比在飞行中的低动量的反中子，测量OBELIX合作。与已知的$p \bar p$原子态的分支比进行比较。发现反应$\bar n p \to π^+π^0$的支化比与从$ p \bar p$ -数据得出的结果相比受到抑制。它还表明，没有所谓的动态I=0振幅抑制的过程$N\bar N \to K\bar K$。
Semileptonic decays $Λ_c^+ \to Λ\ell^+ ν_\ell\,\,(\ell=e,μ)$ in the covariant quark model and comparison with the new absolute branching fraction measurements of Belle and BESIII
Measurement of the H to ZZ branching fraction at 350 GeV and 3 TeV CLIC
在本文中，我们调查的前景，测量分支分数的标准模型希格斯玻色子衰变到一对$Z$玻色子在未来的紧凑型线性对撞机（CLIC）在350 GeV和3 TeV的质心能量。使用CLIC探测器的详细模拟进行研究，同时考虑到所有相关的物理和光束诱导的背景过程。结果表明，在质心能量为350 GeV（3 TeV）时，假设积分亮度为1 ab $^{-1}$（5 ab $^{-1}$），用半轻子末态可以测量出Higgs产生截面和分支分数BR的乘积（${H\rightarrow\thinspace ZZ^\ast}$），相对统计不确定度为20%（3.0%）.
