Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Capturing ultrafast magnetic dynamics by time-resolved soft x-ray
  magnetic circular dichroism   Experiments of time-resolved x-ray magnetic circular dichroism (Tr-XMCD) and
resonant x-ray scattering at a beamline BL07LSU in SPring-8 with a
time-resolution of under 50 ps are presented. A micro-channel plate is utilized
for the Tr-XMCD measurements at nearly normal incidence both in the partial
electron and total fluorescence yield (PEY and TFY) modes at the L2,3
absorption edges of the 3d transition-metals in the soft x-ray region. The
ultrafast photo-induced demagnetization within 50 ps is observed on the
dynamics of a magnetic material of FePt thin film, having a distinct threshold
of the photon density. The spectrum in the PEY mode is less-distorted both at
the L2,3 edges compared with that in the TFY mode and has the potential to
apply the sum rule analysis for XMCD spectra in pump-probed experiments.

19
The categories of this paper are: eess
20
The categories of this paper are: acc-phys
10
The categories of this paper are: q-bio
23
The categories of this paper are: solv-int
33
The categories of this paper are: plasm-ph
13
The categories of this paper are: quant-ph
15
The categories of this paper are: nucl-ex
1
The categories of this paper are: cs
28
The categories of this paper are: alg-geom
17
The categories of this paper are: q-fin
36
The categories of this paper are: cmp-lg
30
The categories of this paper are: q-alg
34
The categories of this paper are: chem-ph
29
The categories of this paper are: funct-an
25
The categories of this paper are: patt-sol
35
The categories of this paper are: mtrl-th