  The KOTO experiment is a particle physics experiment located in J-PARC,
Japan, aiming to explore physics beyond the Standard Model by measuring the
branching ratio of the $K_L\rightarrow\pi^{0}\nu\bar{\nu}$ decay. This decay
has not yet been observed. The branching ratio predicted by the Standard Model
of $(3.0\pm0.3)\times10^{-11}$ and the current experimental upper limit
established by KEK E391a is $2.6\times10^{-8}$.
  The signal of $K_L\rightarrow\pi^{0}\nu\bar{\nu}$ decay has the signature of
two photons on the calorimeter with no signal on the veto detectors. It also
has a large transverse momentum due to missing neutrinos. Kaons that decay
outside the beam line with final product of two photons, such as
$K_L\rightarrow\gamma\gamma$ and $K_L\rightarrow\pi^{+}\pi^{-}\pi^{0}$, can
appear to have large transverse momentum due to kaon scattering and beam
interaction with the detectors. These off-axis kaon decay events can impact the
upper limit of $K_L\rightarrow\pi^{0}\nu\bar{\nu}$ branching ratio. Aluminum
targets located at the upstream of the KOTO detector and inside the
decay-volume were used to study kaon beam profile, which provided off-axis kaon
decay vertex information. The beam profile provided insights on background
contributions to the signal. Studies on the kaon beam profile and background
identification from kaon scattering were presented in this talk.
