Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Top-quark flavor-changing $tqZ$ couplings and rare $\Delta F=1$
  processes   We model-independently study the impacts of anomalous $tqZ$ couplings
($q=u,c$), which lead to the $t\to q Z$ decays, on low energy flavor physics.
It is found that the $tuZ$-coupling effect can significantly affect the rare
$K$ and $B$ decays, whereas the $tcZ$-coupling effect is small. Using the
ATLAS's branching ratio (BR) upper bound of $BR(t\to uZ) < 1.7\times 10^{-4}$,
the influence of the anomalous $tuZ$-coupling on the rare decays can be found
as follows: (a) The contribution to the Kaon direct CP violation can be up to
$Re(\epsilon'/\epsilon) \lesssim 0.8 \times 10^{-3}$; (b) $BR(K^+\to \pi^+ \nu
\bar \nu) \lesssim 12 \times 10^{-11}$ and $BR(K_L \to \pi^0 \nu\bar
\nu)\lesssim 7.9 \times 10^{-11}$; (c) the BR for $K_S \to \mu^+ \mu^-$
including the long-distance effect can be enhanced by $11\%$ with respect to
the standard model result, and (d) $BR(B_d \to \mu^+ \mu^-) \lesssim 1.97
\times 10^{-10}$. In addition, although $Re(\epsilon'/\epsilon)$ cannot be
synchronously enhanced with $BR(K_L\to \pi^0 \nu \bar\nu)$ and $BR(K_S\to \mu^+
\mu^-)$ in the same region of the CP-violating phase, the values of
$Re(\epsilon'/\epsilon)$, $BR(K^+ \to \pi^+ \nu \bar\nu)$, and $BR(B_d \to
\mu^+ \mu^-)$ can be simultaneously increased.

10
The categories of this paper are: q-bio
13
The categories of this paper are: quant-ph
27
The categories of this paper are: comp-gas
32
The categories of this paper are: atom-ph
7
The categories of this paper are: hep-th
34
The categories of this paper are: chem-ph
28
The categories of this paper are: alg-geom
20
The categories of this paper are: acc-phys
11
The categories of this paper are: hep-lat
1
The categories of this paper are: cs
24
The categories of this paper are: dg-ga
18
The categories of this paper are: econ
12
The categories of this paper are: nucl-th
19
The categories of this paper are: eess
35
The categories of this paper are: mtrl-th
17
The categories of this paper are: q-fin