Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Observation of Transverse $\Lambda/\bar{\Lambda}$ Hyperon Polarization
  in $e^+e^-$ Annihilation at Belle   We report the first observation of the spontaneous polarization of $\Lambda$
and $\bar{\Lambda}$ hyperons transverse to the production plane in $e^+e^-$
annihilation, which is attributed to the effect arising from a polarizing
fragmentation function. For inclusive $\Lambda/\bar{\Lambda}$ production, we
also report results with subtracted feed-down contributions from $\Sigma^0$ and
charm. This measurement uses a dataset of 800.4 fb$^{-1}$ collected by the
Belle experiment at or near a center-of-mass energy of 10.58 GeV. We observe a
significant polarization that rises with the fractional energy carried by the
$\Lambda/\bar{\Lambda}$ hyperon.

34
The categories of this paper are: chem-ph
1
The categories of this paper are: cs
20
The categories of this paper are: acc-phys
7
The categories of this paper are: hep-th
35
The categories of this paper are: mtrl-th
22
The categories of this paper are: chao-dyn
25
The categories of this paper are: patt-sol
5
The categories of this paper are: gr-qc
32
The categories of this paper are: atom-ph
15
The categories of this paper are: nucl-ex
16
The categories of this paper are: stat
37
The categories of this paper are: supr-con
30
The categories of this paper are: q-alg
21
The categories of this paper are: adap-org
13
The categories of this paper are: quant-ph
29
The categories of this paper are: funct-an