论文标题
$λ_\ mathrm {c}^{+} $生产的首次测量降低至$ p_ \ mathrm {t} = 0 $ in PP和p-pb碰撞，$ \ sqrt {s_ \ mathrm {s_ \ mathrm {nn}} = 5.02
First measurement of $Λ_\mathrm{c}^{+}$ production down to $p_\mathrm{T} = 0$ in pp and p-Pb collisions at $\sqrt{s_\mathrm{NN}} = 5.02$ TeV
论文作者
论文摘要
提示$ \ mathrm {λ_{C}^{+}} $ BARYONS的产生已在横向动量间隔中以中间速度进行测量$ \ sqrt {s_ \ mathrm {nn}} = 5.02 $ tev。该测量是在衰减通道$ {\rmλ_{c}^{+} \对p k^{0} _ {s}} $上进行的，该\通过使用Kalman-Filter algoriter vertexing algorithm和用于机器学习方法的方法，通过应用新的衰变重建技术来进行。 The $p_{\rm T}$-integrated $\mathrm {Λ_{c}^{+}}$ production cross sections in both collision systems were determined and used along with the measured yields in Pb-Pb collisions to compute the $p_{\rm T}$-integrated nuclear modification factors $R_{\rm pPb}$ and $ \ mathrm {aa} $ of $ \ mathrm {λ_{c}^{+}} $ baryons，它们与考虑核修改Parton分布功能的模型计算进行了比较。 $ \ mathrm {λ_{c}^{+}/d^0} $ baryon to-meson屈服比率是PP和P-PB碰撞的。介绍了与包括修改的强体化过程的模型的比较，并讨论了结果对HADRONIC碰撞中魅力强调的理解的含义。对PP碰撞的P-PB碰撞，可以看到$ \ mathrm {λ_{C}^{c}^{c}^{c}^{c}^{c}^{c}^{λ_{λ_{λ_{λ_{λ_{λ_{λ_{λ_{c}^coldision相对于PP碰撞的显着修改（$3.7σ$）的重大修改（$3.7σ$）在不确定性中的两个碰撞系统之间保持一致。
The production of prompt $\mathrm {Λ_{c}^{+}}$ baryons has been measured at midrapidity in the transverse momentum interval $0<p_{\rm T}<1$ GeV/$c$ for the first time, in pp and p-Pb collisions at a centre-of-mass energy per nucleon-nucleon collision $\sqrt{s_\mathrm{NN}} = 5.02$ TeV. The measurement was performed in the decay channel ${\rm Λ_{c}^{+}\to p K^{0}_{S}}$ by applying new decay reconstruction techniques using a Kalman-Filter vertexing algorithm and adopting a machine-learning approach for the candidate selection. The $p_{\rm T}$-integrated $\mathrm {Λ_{c}^{+}}$ production cross sections in both collision systems were determined and used along with the measured yields in Pb-Pb collisions to compute the $p_{\rm T}$-integrated nuclear modification factors $R_{\rm pPb}$ and $R_\mathrm{AA}$ of $\mathrm{Λ_{c}^{+}}$ baryons, which are compared to model calculations that consider nuclear modification of the parton distribution functions. The $\mathrm{Λ_{c}^{+}/D^0}$ baryon-to-meson yield ratio is reported for pp and p-Pb collisions. Comparisons with models that include modified hadronisation processes are presented, and the implications of the results on the understanding of charm hadronisation in hadronic collisions are discussed. A significant ($3.7σ$) modification of the mean transverse momentum of $\mathrm {Λ_{c}^{+}}$ baryons is seen in p-Pb collisions with respect to pp collisions, while the $p_{\rm T}$-integrated $\mathrm{Λ_{c}^{+}/D^0}$ yield ratio was found to be consistent between the two collision systems within the uncertainties.
