Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Life after eruption - III. Orbital periods of the old novae V365 Car, AR
  Cir, V972 Oph, HS Pup, V909 Sgr, V373 Sct and CN Vel   We present time-series photometric and spectroscopic data for seven old
novae. They are used to derive the orbital period for the systems V365 Car
(5.35 h), AR Cir (5.14 h), V972 Oph (6.75 h), HS Pup (6.41 h), V373 Sct (3.69
h), V909 Sgr (3.43 h) and CN Vel (5.29 h). Their addition increases the number
of orbital periods for novae by ~10 per cent. The eclipsing nature of V909 Sgr
is confirmed, and in three other cases (V365 Car, Ar Cir and V373 Sct) we
detect significant photometric orbital variability with amplitudes >=0.2 mag in
R. The resulting period distribution is briefly discussed. We furthermore
provide new measurements for the previously ambiguous coordinates for AR Cir
and CN Vel and the identification of a new probable W UMa variable in the field
of V909 Sgr. The spectrum of V972 Oph presents an emission feature redward of
Halpha which we tentatively identify with the CII 6578/6583 doublet. It is
shown that this line originates in the binary and not in a shell, and to our
knowledge this is the first time that it has been detected in such quality in a
cataclysmic variable (CV). We argue that this line could be more common in CVs,
but that it can be easily masked by the broad Halpha emission that is typical
for these systems. A closer inspection of the line profiles of the other novae
indeed reveals an extended red wing in V365 Car, CN Vel and AR Cir. In the
latter system additionally an absorption counterpart blueward of Halpha is
detected and thus in this case a bipolar outflow appears as a more likely
scenario rather than CII emission.

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The categories of this paper are: econ
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The categories of this paper are: nlin
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The categories of this paper are: eess
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The categories of this paper are: atom-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: plasm-ph
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The categories of this paper are: physics
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The categories of this paper are: comp-gas
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The categories of this paper are: supr-con
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The categories of this paper are: nucl-ex
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The categories of this paper are: alg-geom
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The categories of this paper are: solv-int
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The categories of this paper are: chao-dyn
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The categories of this paper are: mtrl-th
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The categories of this paper are: stat
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The categories of this paper are: math