Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Dynamic clustering in active colloidal suspensions with chemical
  signaling   In this paper, we explore experimentally the phase behavior of a dense active
suspension of self- propelled colloids. In addition to a solid-like and a
gas-like phase observed for high and low densities, a novel cluster phase is
reported at intermediate densities. This takes the form of a stationary
assembly of dense aggregates, with an average size which grows with activity as
a linear function of the self-propelling velocity. While different possible
scenarii can be considered to account for these observations - such as a
generic velocity weakening instability recently put forward -, we show that the
experimental results are reproduced by a chemotactic aggregation mechanism,
originally introduced to account for bacterial aggregation, and accounting here
for diffusiophoretic chemical interaction between colloidal swimmers.

29
The categories of this paper are: funct-an
28
The categories of this paper are: alg-geom
11
The categories of this paper are: hep-lat
27
The categories of this paper are: comp-gas
25
The categories of this paper are: patt-sol
20
The categories of this paper are: acc-phys
32
The categories of this paper are: atom-ph
0
The categories of this paper are: hep-ph
24
The categories of this paper are: dg-ga
30
The categories of this paper are: q-alg
13
The categories of this paper are: quant-ph
9
The categories of this paper are: nlin
31
The categories of this paper are: ao-sci
35
The categories of this paper are: mtrl-th
1
The categories of this paper are: cs
34
The categories of this paper are: chem-ph