Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: An evolutionary study of the pulsating subdwarf B eclipsing binary
  PG1336-018 (NY Vir)   The formation of subdwarf B (sdB) stars is not well understood within the
current framework of stellar single and binary evolution. In this study, we
focus on the formation and evolution of the pulsating sdB star in the very
short-period eclipsing binary PG1336-018. We aim at refining the formation
scenario of this unique system, so that it can be confronted with observations.
We probe the stellar structure of the progenitors of sdB stars in short-period
binaries using detailed stellar evolution calculations. Applying this to
PG1336-018 we reconstruct the common-envelope phase during which the sdB star
was formed. The results are interpreted in terms of the standard
common-envelope formalism (the alpha-formalism) based on the energy equation,
and an alternative description (the gamma-formalism) using the angular momentum
equation. We find that if the common-envelope evolution is described by the
alpha-formalism, the sdB progenitor most likely experienced a helium flash. We
then expect the sdB mass to be between 0.39 and 0.48 Msun, and the sdB
progenitor initial mass to be below ~2 Msun. However, the results for the
gamma-formalism are less restrictive, and a broader sdB mass range (0.3 - 0.8
Msun) is possible in this case. Future seismic mass determination will give
strong constraints on the formation of PG1336-018 and, in particular, on the CE
phase.

15
The categories of this paper are: nucl-ex
16
The categories of this paper are: stat
18
The categories of this paper are: econ
5
The categories of this paper are: gr-qc
36
The categories of this paper are: cmp-lg
30
The categories of this paper are: q-alg
1
The categories of this paper are: cs
33
The categories of this paper are: plasm-ph
32
The categories of this paper are: atom-ph
14
The categories of this paper are: math-ph
22
The categories of this paper are: chao-dyn
12
The categories of this paper are: nucl-th
35
The categories of this paper are: mtrl-th
28
The categories of this paper are: alg-geom
7
The categories of this paper are: hep-th
3
The categories of this paper are: physics