Many measurements and searches for physics beyond the standard model at the
LHC rely on the efficient identification of heavy-flavour jets, i.e. jets
originating from bottom or charm quarks. In this paper, the discriminating
variables and the algorithms used for heavy-flavour jet identification during
the first years of operation of the CMS experiment in proton-proton collisions
at a centre-of-mass energy of 13 TeV, are presented. Heavy-flavour jet
identification algorithms have been improved compared to those used previously
at centre-of-mass energies of 7 and 8 TeV. For jets with transverse momenta in
the range expected in simulated $\mathrm{t}\overline{\mathrm{t}}$ events, these
new developments result in an efficiency of 68% for the correct identification
of a b jet for a probability of 1% of misidentifying a light-flavour jet. The
improvement in relative efficiency at this misidentification probability is
about 15%, compared to previous CMS algorithms. In addition, for the first time
algorithms have been developed to identify jets containing two b hadrons in
Lorentz-boosted event topologies, as well as to tag c jets. The large data
sample recorded in 2016 at a centre-of-mass energy of 13 TeV has also allowed
the development of new methods to measure the efficiency and misidentification
probability of heavy-flavour jet identification algorithms. The heavy-flavour
jet identification efficiency is measured with a precision of a few per cent at
moderate jet transverse momenta (between 30 and 300 GeV) and about 5% at the
highest jet transverse momenta (between 500 and 1000 GeV).

本文介绍了 CMS 实验在质心能量为 13TeV 的质子 - 质子碰撞中，用于识别重味喷注的鉴别变量和算法，并开发出新的算法以提高重味喷注鉴别的效率和精确度，同时还实现了对包含两个 $b$ 强子的喷注和 $c$ 喷注的鉴别，目前以 15% 左右的提高在 1% 误识率下正确识别 $b$ 喷注的效率，同时在适中的喷注横向动量下准确性高可达几个百分点，而在高喷注横向动量下也可达到约 5%。