The CMS apparatus was identified, a few years before the start of the LHC
operation at CERN, to feature properties well suited to particle-flow (PF)
reconstruction: a highly-segmented tracker, a fine-grained electromagnetic
calorimeter, a hermetic hadron calorimeter, a strong magnetic field, and an
excellent muon spectrometer. A fully-fledged PF reconstruction algorithm tuned
to the CMS detector was therefore developed and has been consistently used in
physics analyses for the first time at a hadron collider. For each collision,
the comprehensive list of final-state particles identified and reconstructed by
the algorithm provides a global event description that leads to unprecedented
CMS performance for jet and hadronic tau decay reconstruction, missing
transverse momentum determination, and electron and muon identification. This
approach also allows particles from pileup interactions to be identified and
enables efficient pileup mitigation methods. The data collected by CMS at a
centre-of-mass energy of 8 TeV show excellent agreement with the simulation and
confirm the superior PF performance at least up to an average of 20 pileup
interactions.

该论文介绍了针对 CMS 探测器开发的全面的局域流重建算法，该算法已成功应用于首个强子对撞机物理分析，并且在堆积衰减、能量分辨率等方面具有优越的性能表现。

CMS 探测器中的粒子流重建和全局事件描述

Particle-flow reconstruction and global event description with the CMS  detector

We present a new software package designed to reduce the computational burden
of hadron collider measurements in Parton Distribution Function (PDF) fits. The
APFELgrid package converts interpolated weight tables provided by APPLgrid
files into a more efficient format for PDF fitting by the combination with PDF
and $\alpha_s$ evolution factors provided by APFEL. This combination
significantly reduces the number of operations required to perform the
calculation of hadronic observables in PDF fits and simplifies the structure of
the calculation into a readily optimised scalar product. We demonstrate that
our technique can lead to a substantial speed improvement when compared to
existing methods without any reduction in numerical accuracy.

本文介绍的新软件包可大大改善强子对撞机测量中的 Parton Distribution Function (PDF) 拟合计算负担，从而实现了数值精度不变的前提下，显著提升计算速度。