Publication details for Prof F Richard StephensonShara, Michael M., Drissen, Laurent, Martin, Thomas, Alarie, Alexandre & Stephenson, F. Richard (2017). When does an old nova become a dwarf nova? Kinematics and age of the nova shell of the dwarf nova AT Cancri. Monthly Notices of the Royal Astronomical Society 465(1): 739-745.
- Publication type: Journal Article
- ISSN/ISBN: 0035-8711 (print), 1365-2966 (electronic)
- DOI: 10.1093/mnras/stw2753
- Further publication details on publisher web site
- Durham Research Online (DRO) - may include full text
Author(s) from Durham
The Z Cam-type dwarf nova AT Cancri (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 time-scale 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, Canada–France–Hawaii Telescope's recently commissioned imaging Fourier transform spectrometer. These range from −455 to +490 km s−1. Coupled with the known distance to AT Cnc of 460 pc, 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
yr ago. This is the most rapid transition from a high mass-transfer rate, nova-like 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 the deduced outburst date (within a century of 1686 CE) of AT Cnc to a ‘guest star’ reported in the constellation Cancer by Korean observers in 1645 CE.