Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Correlation functions for a di-neutron condensate in asymmetric nuclear
  matter   Recent calculations with an effective isospin dependent contact interaction
show the possibility of the crossover from superfluidity of neutron Cooper
pairs in $^1S_0$ pairing channel to Bose-Einstein condensation (BEC) of
di-neutron bound states in dilute nuclear matter. The density and spin
correlation functions are calculated for a di-neutron condensate in asymmetric
nuclear matter with the aim to find the possible features of the BCS-BEC
crossover. It is shown that the zero-momentum transfer spin correlation
function satisfies the sum rule at zero temperature. In symmetric nuclear
matter, the density correlation function changes sign at low momentum transfer
across the BCS-BEC transition and this feature can be considered as a signature
of the crossover. At finite isospin asymmetry, this criterion gives too large
value for the critical asymmetry $\alpha_c^d\sim0.9$, at which the BEC state is
quenched. Therefore, it can be trusted for the description of the
density-driven BCS-BEC crossover of neutron pairs only at small isospin
asymmetry.
  This result generalizes the conclusion of the study in Phys. Rev. Lett. {\bf
95}, 090402 (2005), where the change of sign of the density correlation
function at low momentum transfer in two-component quantum fermionic atomic gas
with the balanced populations of fermions of different species was considered
as an unambiguous signature of the BCS-BEC transition.

29
The categories of this paper are: funct-an
20
The categories of this paper are: acc-phys
15
The categories of this paper are: nucl-ex
28
The categories of this paper are: alg-geom
26
The categories of this paper are: bayes-an
3
The categories of this paper are: physics
0
The categories of this paper are: hep-ph
25
The categories of this paper are: patt-sol
17
The categories of this paper are: q-fin
36
The categories of this paper are: cmp-lg
8
The categories of this paper are: hep-ex
37
The categories of this paper are: supr-con
27
The categories of this paper are: comp-gas
18
The categories of this paper are: econ
10
The categories of this paper are: q-bio
1
The categories of this paper are: cs