Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Elliptic flow and nuclear modification factors of D-mesons at FAIR in a
  Hybrid-Langevin approach   The Compressed Baryonic Matter (CBM) experiment at the Facility for
Anti-proton and Ion Research (FAIR) will provide new possibilities for
charm-quark ($D$-meson) observables in heavy-ion collisions at low collision
energies and high baryon densities. To predict the collective flow and nuclear
modification factors of charm quarks in this environment, we apply a Langevin
approach for the transport of charm quarks in the UrQMD (hydrodynamics +
Boltzmann) hybrid model. Due to the inclusion of event-by-event fluctuations
and a full (3+1) dimensional hydrodynamical evolution, the UrQMD hybrid
approach provides a realistic evolution of the matter produced in heavy-ion
collisions.
  As drag and diffusion coefficients we use a resonance approach for elastic
heavy-quark scattering and assume a decoupling temperature of the charm quarks
from the hot medium of $130\, \MeV$. Hadronization of the charm quarks to
$D$-mesons by coalescence is included. Since the initial charm-quark
distribution at FAIR is unknown, we utilize two different initial charm-quark
distributions in our approach to estimate the uncertainty of these predictions.
We present calculations of the nuclear modification factor, $R_{AA}$, as well
as for the elliptic flow, $v_2$, in Pb+Pb collisions at
$E_{lab}=25\,\text{AGeV}$. The different medium modifications of $D$-mesons and
$\bar{D}$-mesons at high baryon-chemical potential are explored by modified
drag- and diffusion-coefficients using the corresponding fugacity factor. Here
we find a considerably larger medium modification for $\bar{\mathrm{D}}$- than
for $D$-mesons.

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The categories of this paper are: supr-con
19
The categories of this paper are: eess
30
The categories of this paper are: q-alg
33
The categories of this paper are: plasm-ph
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The categories of this paper are: funct-an
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The categories of this paper are: adap-org
3
The categories of this paper are: physics
22
The categories of this paper are: chao-dyn
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The categories of this paper are: patt-sol
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The categories of this paper are: astro-ph
2
The categories of this paper are: math
15
The categories of this paper are: nucl-ex
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The categories of this paper are: cond-mat
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The categories of this paper are: alg-geom
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The categories of this paper are: chem-ph
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The categories of this paper are: acc-phys