Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Bose-Einstein condensation in finite drops of alpha particles   Ground-state properties of finite drops of alpha particles (Q-balls) are
studied within a field-theoretical approach in the mean-field approximation.
The strong interaction of alphas is described by the scalar field with a sextic
Skyrme-like potential. The radial profiles of scalar and Coulomb fields are
found by solving the coupled system of Klein-Gordon and Poisson equations. A
generalized condition for Bose-Einstein condensation in a finite system of
charged bosons is formulated in terms of particle effective mass. The formation
of shell-like nuclei, with vanishing density around the centre, is predicted at
high enough attractive strength of Skyrme potential. The equilibrium values of
energy and baryon number of Q-balls and Q-shells are calculated for different
sets of interaction parameters. Empirical binding energies of alpha-conjugate
nuclei are reproduced only if the gradient term in the Lagrangian is strongly
enhanced. It is demonstrated that this enhancement can be explained by nonzero
range of strong alpha-alpha interaction.

22
The categories of this paper are: chao-dyn
25
The categories of this paper are: patt-sol
19
The categories of this paper are: eess
1
The categories of this paper are: cs
35
The categories of this paper are: mtrl-th
31
The categories of this paper are: ao-sci
4
The categories of this paper are: cond-mat
29
The categories of this paper are: funct-an
6
The categories of this paper are: astro-ph
13
The categories of this paper are: quant-ph
11
The categories of this paper are: hep-lat
24
The categories of this paper are: dg-ga
21
The categories of this paper are: adap-org
14
The categories of this paper are: math-ph
3
The categories of this paper are: physics
7
The categories of this paper are: hep-th