Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: When does an old nova become a dwarf nova? Kinematics and age of the
  nova shell of the dwarf nova AT Cnc   The Z Cam-type dwarf nova AT Cnc displays a classical nova (CN) shell,
demonstrating that mass transfer in cataclysmic binaries decreases
substantially after a CN eruption. The hibernation scenario of cataclysmic
binaries predicts such a decrease, on a timescale of a few centuries. In order
to measure the time since AT Cnc's last CN eruption, we have measured the
radial velocities of a hundred clumps in its ejecta with SITELLE, CFHT's
recently commissioned imaging Fourier transform spectrometer. These range from
-455 to +490 km/s. Coupled with the known distance to AT Cnc of 460 pc (Shara
2012), the size of AT Cnc's shell, and a simple model of nova ejecta
deceleration, we determine that the last CN eruption of this system occurred
$330_{-90}^{+135}$ years ago. This is the most rapid transition from a high
mass transfer rate, novalike variable to a low mass transfer rate, dwarf nova
yet measured, and in accord with the hibernation scenario of cataclysmic
binaries. We conclude by noting the similarity in deduced outburst date (within
a century of 1686 CE) of AT Cnc with a "guest star" reported in the
constellation Cancer by Korean observers in 1645 CE.

11
The categories of this paper are: hep-lat
1
The categories of this paper are: cs
34
The categories of this paper are: chem-ph
22
The categories of this paper are: chao-dyn
33
The categories of this paper are: plasm-ph
9
The categories of this paper are: nlin
14
The categories of this paper are: math-ph
12
The categories of this paper are: nucl-th
3
The categories of this paper are: physics
23
The categories of this paper are: solv-int
0
The categories of this paper are: hep-ph
31
The categories of this paper are: ao-sci
25
The categories of this paper are: patt-sol
28
The categories of this paper are: alg-geom
36
The categories of this paper are: cmp-lg
18
The categories of this paper are: econ