Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A New Nonlinear Liquid Drop Model. Clusters as Solitons on The Nuclear
  Surface   By introducing in the hydrodynamic model, i.e. in the hydrodynamic equations
and the corresponding boundary conditions, the higher order terms in the
deviation of the shape, we obtain in the second order the Korteweg de Vries
equation (KdV). The same equation is obtained by introducing in the liquid drop
model (LDM), i.e. in the kinetic, surface and Coulomb terms, the higher terms
in the second order. The KdV equation has the cnoidal waves as steady-state
solutions. These waves could describe the small anharmonic vibrations of
spherical nuclei up to the solitary waves. The solitons could describe the
preformation of clusters on the nuclear surface. We apply this nonlinear liquid
drop model to the alpha formation in heavy nuclei. We find an additional
minimum in the total energy of such systems, corresponding to the solitons as
clusters on the nuclear surface. By introducing the shell effects we choose
this minimum to be degenerated with the ground state. The spectroscopic factor
is given by the ratio of the square amplitudes in the two minima.

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The categories of this paper are: atom-ph
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The categories of this paper are: ao-sci
17
The categories of this paper are: q-fin
35
The categories of this paper are: mtrl-th
0
The categories of this paper are: hep-ph
36
The categories of this paper are: cmp-lg
14
The categories of this paper are: math-ph
8
The categories of this paper are: hep-ex
20
The categories of this paper are: acc-phys
7
The categories of this paper are: hep-th
4
The categories of this paper are: cond-mat
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The categories of this paper are: dg-ga
18
The categories of this paper are: econ
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The categories of this paper are: funct-an
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The categories of this paper are: supr-con
22
The categories of this paper are: chao-dyn