Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Measurement of prompt $\mathrm{D}^0$ and $\overline{\mathrm{D}}^0$ meson
  azimuthal asymmetry and search for strong electric fields in PbPb collisions
  at $\sqrt{s_\mathrm{NN}} =$ 5.02 TeV   The strong Coulomb field created in ultrarelativistic heavy ion collisions is
expected to produce a rapidity-dependent difference ($\Delta v_2$) in the
second Fourier coefficient of the azimuthal distribution (elliptic flow, $v_2$)
between $\mathrm{D}^0$ ($\mathrm{\bar{u}c}$) and $\overline{\mathrm{D}}^0$
($\mathrm{u\bar{c}}$) mesons. Motivated by the search for evidence of this
field, the CMS detector at the LHC is used to perform the first measurement of
$\Delta v_2$. The rapidity-averaged value is found to be $\langle\Delta v_2
\rangle =$ 0.001 $\pm$ 0.001 (stat) $\pm$ 0.003 (syst) in PbPb collisions at
$\sqrt{s_\mathrm{NN}} =$ 5.02 TeV. In addition, the influence of the collision
geometry is explored by measuring the $\mathrm{D}^0$ and
$\overline{\mathrm{D}}^0$ mesons $v_2$ and triangular flow coefficient ($v_3$)
as functions of rapidity, transverse momentum ($p_\mathrm{T}$), and event
centrality (a measure of the overlap of the two Pb nuclei). A clear centrality
dependence of prompt $\mathrm{D}^0$ meson $v_2$ values is observed, while the
$v_3$ is largely independent of centrality. These trends are consistent with
expectations of flow driven by the initial-state geometry.

27
The categories of this paper are: comp-gas
28
The categories of this paper are: alg-geom
37
The categories of this paper are: supr-con
9
The categories of this paper are: nlin
4
The categories of this paper are: cond-mat
30
The categories of this paper are: q-alg
35
The categories of this paper are: mtrl-th
7
The categories of this paper are: hep-th
33
The categories of this paper are: plasm-ph
32
The categories of this paper are: atom-ph
36
The categories of this paper are: cmp-lg
10
The categories of this paper are: q-bio
19
The categories of this paper are: eess
21
The categories of this paper are: adap-org
0
The categories of this paper are: hep-ph
24
The categories of this paper are: dg-ga