Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: (p,T,H) phase diagram of Heavy Fermion systems : Some systematics and
  some surprises from ytterbium   Pressure is the cleanest way to tune heavy fermion systems to a quantum phase
transition in order to study the rich physics and competing phases, and the
comparison between ytterbium and cerium systems is particularly fruitful. We
briefly review the mechanisms in play and show some examples of expected and
unexpected behaviour. We emphasize the importance of the valence changes under
pressure and show how modern synchrotron techniques can accurately determine
this, including at low temperature.

14
The categories of this paper are: math-ph
1
The categories of this paper are: cs
31
The categories of this paper are: ao-sci
27
The categories of this paper are: comp-gas
32
The categories of this paper are: atom-ph
16
The categories of this paper are: stat
35
The categories of this paper are: mtrl-th
29
The categories of this paper are: funct-an
10
The categories of this paper are: q-bio
9
The categories of this paper are: nlin
19
The categories of this paper are: eess
12
The categories of this paper are: nucl-th
23
The categories of this paper are: solv-int
25
The categories of this paper are: patt-sol
36
The categories of this paper are: cmp-lg
2
The categories of this paper are: math