Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On the Parton Interpretation of Quark Fragmentation into Hadrons with
  Different Spins   We calculate the spin density matrix of the hadron $h$ created via quark
fragmentation in the process $e^-e^+ \to q\bar q \to h + X$. In the case of
$h=\Lambda$ the experimental data could possibly elucidate the problem of
$s$-quark contribution to the spin of the $\Lambda$-hyperon, to be compared
with the case of the proton (``spin crisis''). Generally we find that for
hadrons with spin 1/2 the parton description, using only probabilities, works
much better than for vector particles, since in the former case the non
diagonal matrix elements of the hadron spin density matrix are suppressed by a
small factor $p_T/(z\sqrt s)$, where $p_T$ is the hadron transverse momentum
inside the jet.

31
The categories of this paper are: ao-sci
10
The categories of this paper are: q-bio
14
The categories of this paper are: math-ph
33
The categories of this paper are: plasm-ph
32
The categories of this paper are: atom-ph
29
The categories of this paper are: funct-an
12
The categories of this paper are: nucl-th
35
The categories of this paper are: mtrl-th
21
The categories of this paper are: adap-org
22
The categories of this paper are: chao-dyn
36
The categories of this paper are: cmp-lg
13
The categories of this paper are: quant-ph
11
The categories of this paper are: hep-lat
28
The categories of this paper are: alg-geom
17
The categories of this paper are: q-fin
34
The categories of this paper are: chem-ph