Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Event shape engineering with ALICE   The strong fluctuations in the initial energy density of heavy-ion collisions
allow an efficient selection of events corresponding to a specific initial
geometry. For such "shape engineered events", the elliptic flow coefficient,
$v_2$, of unidentified charged particles, pions and (anti-)protons in Pb-Pb
collisions at $\snn = 2.76$ TeV is measured by the ALICE collaboration. $v_2$
obtained with the event plane method at mid-rapidity, $|\eta|<0.8$, is reported
for different collision centralities as a function of transverse momentum,
$\pt$, out to $\pt=20$ GeV/$c$. The measured $v_2$ for the shape engineered
events is significantly larger or smaller than the average which demonstrates
the ability to experimentally select events with the desired shape of the
initial spatial asymmetry.

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The categories of this paper are: bayes-an
16
The categories of this paper are: stat
11
The categories of this paper are: hep-lat
18
The categories of this paper are: econ
6
The categories of this paper are: astro-ph
29
The categories of this paper are: funct-an
1
The categories of this paper are: cs
4
The categories of this paper are: cond-mat
2
The categories of this paper are: math
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The categories of this paper are: plasm-ph
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The categories of this paper are: comp-gas
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The categories of this paper are: chao-dyn
0
The categories of this paper are: hep-ph
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The categories of this paper are: solv-int
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The categories of this paper are: ao-sci
28
The categories of this paper are: alg-geom