Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Magnetic field dependence of Delta isobars properties in a Skyrme model   The properties of $\Delta$ isobars in a uniform magnetic field are
investigated. In the weak magnetic field region, the general relations between
magnetic moment of nucleons and $\Delta$ isobars are given. In the strong
magnetic field region, the mass and size of $\Delta$ isobars depend on the
increasing of magnetic field strength in different ways: the effective mass of
$\Delta^{++}$, $\Delta^{+}$ and $\Delta^{0}$ first decreases and then
increases, consequently, the size of $\Delta^{++}$, $\Delta^{+}$ and
$\Delta^{0}$ first increases and then decreases; whereas, the effective mass of
$\Delta^{-}$ always increases, and consequently, the size of $\Delta^{-}$
always decreases. The estimation shows in the core part of the magnetar, the
equation of state for $\Delta$ isobars depends on the magnetic field, which
affects the mass limit of the magnetar.

26
The categories of this paper are: bayes-an
6
The categories of this paper are: astro-ph
19
The categories of this paper are: eess
16
The categories of this paper are: stat
37
The categories of this paper are: supr-con
27
The categories of this paper are: comp-gas
10
The categories of this paper are: q-bio
23
The categories of this paper are: solv-int
9
The categories of this paper are: nlin
28
The categories of this paper are: alg-geom
3
The categories of this paper are: physics
8
The categories of this paper are: hep-ex
32
The categories of this paper are: atom-ph
2
The categories of this paper are: math
5
The categories of this paper are: gr-qc
34
The categories of this paper are: chem-ph