Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Dust in brown dwarfs and extra-solar planets. VIII. TiO$_2$ seed
  formation: 3D Monte Carlo versus kinetic approach   We aim to understand the onset of cloud formation {and study the formation
of} TiO$_2$-CCNs. The formation of (TiO$_2$)$_{\rm N}$ clusters as precursors
to extrasolar cloud formation is modelled by two different methods in order to
understand their potential, identify underlying shortcomings, and to validate
our methods. We propose potential spectral tracers for TiO$_2$-CCN formation.
We applied three-dimensional Monte Carlo (3D MC) simulations to model the
collision-induced growth of TiO$_2$-molecules to (TiO$_2$)$_{\rm N}$-clusters
in the free molecular flow regime of an atmospheric gas. We derived individual,
time-dependent (TiO$_2$)$_{\rm N}$ cluster number densities. For $T=1000$K, the
results are compared to a kinetic approach that utilises thermodynamic data for
individual (TiO$_2$)$_{\rm N}$ clusters. The {(TiO$_2$)$_{\rm N}$} cluster size
distribution is temperature dependent and evolves in time until a steady state
is reached. For $T=1000$K, the 3D MC and the kinetic approach agree well
regarding the cluster number densities for $N=1\,\ldots\,10$, the vivid onset
of cluster formation, and the long transition into a steady state.
Collision-induced growth and evaporation simulated using a 3D MC approach
enables a faster onset of cluster growth through nucleation bursts. Different
size distributions develop for monomer-cluster and for cluster-cluster growth,
with the largest clusters appearing for cluster-cluster growth. The
(TiO$_2$)$_N$ cluster growth efficiency has a sweet-spot temperature at
$\approx 1000$K at which CCN formation is triggered. The combination of local
thermodynamic conditions and chemical processes therefore determines CCN
formation efficiency.

3
The categories of this paper are: physics
23
The categories of this paper are: solv-int
17
The categories of this paper are: q-fin
31
The categories of this paper are: ao-sci
11
The categories of this paper are: hep-lat
13
The categories of this paper are: quant-ph
28
The categories of this paper are: alg-geom
37
The categories of this paper are: supr-con
4
The categories of this paper are: cond-mat
26
The categories of this paper are: bayes-an
24
The categories of this paper are: dg-ga
30
The categories of this paper are: q-alg
22
The categories of this paper are: chao-dyn
21
The categories of this paper are: adap-org
1
The categories of this paper are: cs
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The categories of this paper are: hep-ex