Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The dune size distribution and scaling relations of barchan dune fields   Barchan dunes emerge as a collective phenomena involving the generation of
thousands of them in so called barchan dune fields. By measuring the size and
position of dunes in Moroccan barchan dune fields, we find that these dunes
tend to distribute uniformly in space and follow an unique size distribution
function. We introduce an analyticalmean-field approach to show that this
empirical size distribution emerges from the interplay of dune collisions and
sand flux balance, the two simplest mechanisms for size selection. The
analytical model also predicts a scaling relation between the fundamental
macroscopic properties characterizing a dune field, namely the inter-dune
spacing and the first and second moments of the dune size distribution.

21
The categories of this paper are: adap-org
10
The categories of this paper are: q-bio
28
The categories of this paper are: alg-geom
34
The categories of this paper are: chem-ph
15
The categories of this paper are: nucl-ex
24
The categories of this paper are: dg-ga
35
The categories of this paper are: mtrl-th
12
The categories of this paper are: nucl-th
33
The categories of this paper are: plasm-ph
18
The categories of this paper are: econ
7
The categories of this paper are: hep-th
26
The categories of this paper are: bayes-an
17
The categories of this paper are: q-fin
8
The categories of this paper are: hep-ex
25
The categories of this paper are: patt-sol
20
The categories of this paper are: acc-phys