论文标题
$ \ sqrt {s _ {\ rm {nn}}} $ = 2.76 TEV
$Λ\rm{K}$ femtoscopy in Pb-Pb collisions at $\sqrt{s_{\rm{NN}}}$ = 2.76 TeV
论文作者
论文摘要
$λ$ k对的散射参数的第一个测量（$λ$ k $^{+} $，$λ$ k $^{ - } $，以及$λ\ mathrm {k^{0} _ {s}}} $）。通过对$ \ sqrt {s _ {\ Mathrm {nn}} $ = 2.76 TEV记录的$ \ sqrt {s _ {s _ {s _ {s _ {s _ {s _ {s _ {s _ {s _ {s _ {s _ {s _ {触发性相关性是由强烈的最终状态相互作用引起的，并且与参数化既可以允许对粒子对的表征进行表征和散射参数的测量。对Theminator 2事件发生器进行的广泛研究提供了对非镜头镜面背景的良好描述，该背景主要来自集体效应，并具有前所未有的精度。此外，与Hijing模拟一起，该模型用于说明粒子衰变馈电引起的残留相关性的贡献。提取的散射参数表明，强力在$λ\ rm {k}^{+} $相互作用中具有排斥性，并且在$λ\ rm {k}^{ - } $相互作用中具有吸引力。数据暗示，和$λ\ rm {k}^{0} _ {s} $相互作用很有吸引力，但是结果的不确定性不允许这样的决定性结论。结果表明，两对之间的不同夸克 - 易夸克相互作用（$ \ rm s \ rm s \ overline {s} $ in $λ$ k $^{+} $和$ \ rm u \ rm u \ rm u \ rm u \ inline {u} $ in $ k $ k $ k $ k $^{ - } $）或从不同的网络中$ net Smange（$ net Smange）（$ a $） $ -2 $ for $λ$ k $^{ - } $）。最后，$λ$ k系统的源半径比相同粒子触发研究外推的预期大。这种效果被解释为由单粒子$λ$和k源分布的时空分离产生的。
The first measurements of the scattering parameters of $Λ$K pairs in all three charge combinations ($Λ$K$^{+}$, $Λ$K$^{-}$, and $Λ\mathrm{K^{0}_{S}}$) are presented. The results are achieved through a femtoscopic analysis of $Λ$K correlations in Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 2.76 TeV recorded by ALICE at the LHC. The femtoscopic correlations result from strong final-state interactions, and are fit with a parametrization allowing for both the characterization of the pair emission source and the measurement of the scattering parameters for the particle pairs. Extensive studies with the THERMINATOR 2 event generator provide a good description of the non-femtoscopic background, which results mainly from collective effects, with unprecedented precision. Furthermore, together with HIJING simulations, this model is used to account for contributions from residual correlations induced by feed-down from particle decays. The extracted scattering parameters indicate that the strong force is repulsive in the $Λ\rm{K}^{+}$ interaction and attractive in the $Λ\rm{K}^{-}$ interaction. The data hint that the and $Λ\rm{K}^{0}_{S}$ interaction is attractive, however the uncertainty of the result does not permit such a decisive conclusion. The results suggest an effect arising either from different quark-antiquark interactions between the pairs ($\rm s\overline{s}$ in $Λ$K$^{+}$ and $\rm u\overline{u}$ in $Λ$K$^{-}$) or from different net strangeness for each system (S = 0 for $Λ$K$^{+}$, and S = $-2$ for $Λ$K$^{-}$). Finally, the $Λ$K systems exhibit source radii larger than expected from extrapolation from identical particle femtoscopic studies. This effect is interpreted as resulting from the separation in space-time of the single-particle $Λ$ and K source distributions.
