Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A general method for the determination of duration of solar cycle maxima   The use of different solar activity indices like sunspot numbers, sunspot
areas, flare index, magnetic fields, etc., allows us to investigate the time
evolution of some specific features of the solar activity and the underlying
dynamo mechanism. One of the problems when using these activity indices for
some statistical analyses is the reliable determination of the maximum phases
of different solar cycles which are generally characterized by a multi-peaked
structure due to the presence of the so-called \emph {Gnevyshev gap}. The main
aim of this work is to propose a general method, without the introduction of ad
hoc heuristic parameters, to determine the duration of a given solar cycle
maximum phase through a long-term solar activity index like the Monthly
Smoothed Sunspot Number (SSN). The resulting extended solar maxima allows us to
include the multi-peaked structure of solar cycles and further the proposed
method allows us to predict the solar maximum duration of the current solar
cycle 24.

2
The categories of this paper are: math
29
The categories of this paper are: funct-an
22
The categories of this paper are: chao-dyn
36
The categories of this paper are: cmp-lg
37
The categories of this paper are: supr-con
30
The categories of this paper are: q-alg
15
The categories of this paper are: nucl-ex
14
The categories of this paper are: math-ph
5
The categories of this paper are: gr-qc
3
The categories of this paper are: physics
9
The categories of this paper are: nlin
27
The categories of this paper are: comp-gas
12
The categories of this paper are: nucl-th
20
The categories of this paper are: acc-phys
35
The categories of this paper are: mtrl-th
17
The categories of this paper are: q-fin