Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Self-adjoint Dirac type Hamiltonians in one space dimension with a mass
  jump   Physical self-adjoint extensions and their spectra of the one-dimensional
Dirac type Hamiltonian operator in which both the mass and velocity are
constant except for a finite jump at one point of the real axis are correctly
found. Different boundary conditions on envelope wave functions are studied,
and the limiting case of equal masses (with no mass jump) is reviewed.
Transport across one-dimensional heterostructures described by the Dirac
equation is considered.

37
The categories of this paper are: supr-con
6
The categories of this paper are: astro-ph
29
The categories of this paper are: funct-an
10
The categories of this paper are: q-bio
19
The categories of this paper are: eess
9
The categories of this paper are: nlin
1
The categories of this paper are: cs
5
The categories of this paper are: gr-qc
33
The categories of this paper are: plasm-ph
24
The categories of this paper are: dg-ga
22
The categories of this paper are: chao-dyn
23
The categories of this paper are: solv-int
8
The categories of this paper are: hep-ex
30
The categories of this paper are: q-alg
4
The categories of this paper are: cond-mat
16
The categories of this paper are: stat