Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Search for $CP$ violation in $D$ decays to radiative and hadronic decays
  and search for rare $D$ decay at Belle   Using the large data sample accumulated by the Belle experiment at KEKB
asymmetry energy $e^+e^-$ Collider, we report the preliminary measurements of
the branching fractions of the radiative decays $D^0 \rightarrow V\gamma$,
where $V$ = $\phi,\bar{K^*}^0, \rho^0$. This is the first observation of the
decay $D^0 \rightarrow \rho^0\gamma$ and also present the preliminary results
of the first measurement of $CP$ asymmetry in these decays. We present the
preliminary result of the $CP$ asymmetry of the $D^0 \rightarrow K^0_S K^0_S$
decay, which is consistent with no $CP$ violation and improves the uncertainty
with respect to the previous measurement of this quantity by more than a factor
of three. Finally, we present the results of the rare charm decay $D^0
\rightarrow \gamma\gamma$, resulting in the most restrictive upper limit to
date.

13
The categories of this paper are: quant-ph
31
The categories of this paper are: ao-sci
2
The categories of this paper are: math
5
The categories of this paper are: gr-qc
17
The categories of this paper are: q-fin
11
The categories of this paper are: hep-lat
3
The categories of this paper are: physics
29
The categories of this paper are: funct-an
37
The categories of this paper are: supr-con
18
The categories of this paper are: econ
24
The categories of this paper are: dg-ga
10
The categories of this paper are: q-bio
26
The categories of this paper are: bayes-an
4
The categories of this paper are: cond-mat
28
The categories of this paper are: alg-geom
36
The categories of this paper are: cmp-lg