Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Measurement of the muon charge asymmetry in inclusive $pp \rightarrow W
  + X$ production at $\sqrt{s} = 7$ TeV at CMS and an improved determination of
  light parton distribution functions   Measurements of the muon charge asymmetry in inclusive $pp \rightarrow WX$
production at $\sqrt{s}=7$ TeV are presented. The data sample corresponds to an
integrated luminosity of 4.7 $\mathrm{fb^{-1}}$ recorded with the CMS detector
at the LHC. With a sample of more than twenty million $W \rightarrow \mu\nu$
events, the statistical precision is greatly improved in comparison to previous
measurements. These new results provide additional constraints on the parton
distribution functions of the proton in the range of the Bjorken scaling
variable $x$ from $10^{-3}$ to $10^{-1}$. These measurements are used together
with the cross sections for inclusive deep inelastic ep scattering at HERA in a
next-to-leading-order QCD analysis.

1
The categories of this paper are: cs
30
The categories of this paper are: q-alg
33
The categories of this paper are: plasm-ph
4
The categories of this paper are: cond-mat
37
The categories of this paper are: supr-con
15
The categories of this paper are: nucl-ex
24
The categories of this paper are: dg-ga
7
The categories of this paper are: hep-th
28
The categories of this paper are: alg-geom
2
The categories of this paper are: math
10
The categories of this paper are: q-bio
18
The categories of this paper are: econ
35
The categories of this paper are: mtrl-th
3
The categories of this paper are: physics
5
The categories of this paper are: gr-qc
23
The categories of this paper are: solv-int