Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Search for $B^{+} \to K^{+} \nu \bar \nu$ decays with an inclusive
  tagging method at the Belle II experiment   This contribution illustrates a new search for the flavor-changing
neutral-current decay ${B^+ \to K^+ \nu \bar \nu}$ performed by the Belle II
experiment at the SuperKEKB asymmetric-energy electron-positron collider. In
this study, a sample corresponding to an integrated luminosity of $63\,
\rm{fb}^{-1}$ collected at the $\rm \Upsilon(4S)$ resonance and an additional
sample of $9\, \rm{fb}^{-1}$ collected at an energy $60\, \rm MeV$ below the
resonance are used. A novel technique, based on an inclusive tagging method and
exploiting the topological features of the ${B^+ \to K^+ \nu \bar \nu}$ decay,
is employed and it provides a higher signal efficiency with respect to the
methods used in the previous searches. No significant signal is observed. An
upper limit of $4.1 \times 10^{-5}$ is set on the ${B^+ \to K^+ \nu \bar \nu}$
branching fraction at the $90\, \%$ confidence level.

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The categories of this paper are: math
27
The categories of this paper are: comp-gas
15
The categories of this paper are: nucl-ex
11
The categories of this paper are: hep-lat
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The categories of this paper are: q-fin
0
The categories of this paper are: hep-ph
20
The categories of this paper are: acc-phys
6
The categories of this paper are: astro-ph
29
The categories of this paper are: funct-an
25
The categories of this paper are: patt-sol
18
The categories of this paper are: econ
9
The categories of this paper are: nlin
32
The categories of this paper are: atom-ph
24
The categories of this paper are: dg-ga
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The categories of this paper are: q-bio
33
The categories of this paper are: plasm-ph