论文标题
b $ _ \ mathrm {c} $（2s）$^+$和b $ _ \ mathrm {c}^*$（2S）$^+$ cross截面比率$ \ sqrt {s} = $ 13 TEV
Measurement of B$_\mathrm{c}$(2S)$^+$ and B$_\mathrm{c}^*$(2S)$^+$ cross section ratios in proton-proton collisions at $\sqrt{s} =$ 13 TeV
论文作者
论文摘要
B $ _ \ MATHRM {C} $（2S）$^+$与B $ _ \ MATHRM {C}^+$，B $ _ \ MATHRM {C}^*$（2S）$^+$ to B $ _ \ $ _ \ MATHRM {C}^+$^$^$^$^$} B $ _ \ MATHRM {C} $（2S）$^+$生产横截面以$ \ sqrt {s} = $ 13 tev的质子 - proton碰撞进行测量，使用CMS实验在LHC上收集的数据样本，与LHC的CMS实验收集的数据样本，与143 fb $^{-1} $的集成液体相对应。这三个测量值是在b $ _ \ mathrm {c}^+$ $梅森相位空间区域中由横向动量$ p_ \ mathrm {t} $ $ \ gt $ 15 gev和绝对快速$ | y | y | $ $ $ $ \ $ \ lt $ 2.4，带有激动的b $ _ \ mathrm mathrm mathrm^$^$^$ {通过B $ _ \ MATHRM {C}^{（*）+}π^+π^ - $重建，其次是B $ _ \ Mathrm {C}^+$ $ \ $ $ $ \ to $ j/$ j/$ j/$ g/$ψπ^+$和J/$ $ $ $ $ $ $ \ $ $ \ to $μ^+μ^+μ^ - $ undeays。 B $ _ \ MATHRM {C} $（2s）$^+$ to b $ _ \ MATHRM {C}^+$，B $ _ \ MATHRM {C}^*$（2S）$（2S）$^+$ to to B $ _ \ _ \ MATHRM {C} B $ _ \ MATHRM {C} $（2s）$^+$横截面比例，包括未知B $ _ \ Mathrm {C}^{（*）} $（2S）$^+$^+$^+$^+$^+$^+$^$ b $ _ \ _ \ mathrm {C} 0.63（stat）$ \ pm $ 0.33（SYST））％（4.69 $ \ pm $ 0.71（stat）$ \ pm $ 0.56（syst））％和1.35 $ \ pm $ 0.32（stat）$ \ pm $ 0.09（SYST）。这些比率均未显示出对$ p_ \ mathrm {t} $或$ | y | $ _ \ mathrm {c} $ meson的显着依赖性。从衰减中的归一化二极管不变质量分布b $ _ \ mathrm {c}^{（*）} $（2S）$^+$ $ \ to $ b $ _ \ MATHRM {C}^{（*）$ $^+π^+π^+π^+π^+π^ - $也已报道。
The ratios of the B$_\mathrm{c}$(2S)$^+$ to B$_\mathrm{c}^+$, B$_\mathrm{c}^*$(2S)$^+$ to B$_\mathrm{c}^+$, and B$_\mathrm{c}^*$(2S)$^+$ to B$_\mathrm{c}$(2S)$^+$ production cross sections are measured in proton-proton collisions at $\sqrt{s} =$ 13 TeV, using a data sample collected by the CMS experiment at the LHC, corresponding to an integrated luminosity of 143 fb$^{-1}$. The three measurements are made in the B$_\mathrm{c}^+$ meson phase space region defined by the transverse momentum $p_\mathrm{T}$ $\gt$ 15 GeV and absolute rapidity $|y|$ $\lt$ 2.4, with the excited B$_\mathrm{c}^{(*)}$(2S)$^+$ states reconstructed through the B$_\mathrm{c}^{(*)+} π^+π^-$, followed by the B$_\mathrm{c}^+$ $\to$ J/$ψπ^+$ and J/$ψ$ $\to$ $μ^+μ^-$ decays. The B$_\mathrm{c}$(2S)$^+$ to B$_\mathrm{c}^+$, B$_\mathrm{c}^*$(2S)$^+$ to B$_\mathrm{c}^+$, and B$_\mathrm{c}^*$(2S)$^+$ to B$_\mathrm{c}$(2S)$^+$ cross section ratios, including the unknown B$_\mathrm{c}^{(*)}$(2S)$^+$ $\to$ B$_\mathrm{c}^{(*)+}π^+π^-$ branching fractions, are (3.47 $\pm$ 0.63 (stat) $\pm$ 0.33 (syst))%, (4.69 $\pm$ 0.71 (stat) $\pm$ 0.56 (syst))%, and 1.35 $\pm$ 0.32 (stat) $\pm$ 0.09 (syst), respectively. None of these ratios shows a significant dependence on the $p_\mathrm{T}$ or $|y|$ of the B$_\mathrm{c}$ meson. The normalized dipion invariant mass distributions from the decays B$_\mathrm{c}^{(*)}$(2S)$^+$ $\to$ B$_\mathrm{c}^{(*)}$$^+ π^+π^-$ are also reported.
