Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Neutron scattering by Dirac multipoles   Ordered magnetic charge created by Dirac multipoles that are magnetic and
polar is examined. It has previously been revealed in the pseudo-gap phase of
high-Tc materials by use of the Kerr effect and magnetic neutron Bragg
diffraction. There are several forms of the polar operator for magnetic neutron
scattering built from spin and electric dipole operators of unpaired electrons.
Construction of Dirac quadrupoles that emerge from centrosymmetric sites used
by Cu ions in the ceramic superconductor Hg1201 is illustrated, together with
selection rules for excitations that will feature in neutron inelastic
scattering, and RIXS experiments. Most reported expressions and results have
universal value, because they are not specific to ceramic superconductors. To
illustrate this aspect of our work we simulate neutron diffraction from a
magnetically ordered iridate (Sr2IrO4).

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The categories of this paper are: hep-th
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The categories of this paper are: econ
30
The categories of this paper are: q-alg
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The categories of this paper are: adap-org
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The categories of this paper are: chao-dyn
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The categories of this paper are: bayes-an
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The categories of this paper are: acc-phys
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The categories of this paper are: funct-an
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The categories of this paper are: q-bio
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The categories of this paper are: ao-sci
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The categories of this paper are: dg-ga
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The categories of this paper are: alg-geom
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The categories of this paper are: math-ph
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The categories of this paper are: nucl-th
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The categories of this paper are: physics
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The categories of this paper are: astro-ph