The Library
Spectroscopic evidence for a 5.4 minute orbital period in HM Cancri
Tools
Tools
Tools
Roelofs, Gijs H. A., Rau, Arne, Marsh, T. R., Steeghs, D., Groot, P. J. and Nelemans, G. (2010) Spectroscopic evidence for a 5.4 minute orbital period in HM Cancri. Astrophysical Journal Letters, Vol.711 (No.2). L138-L142. doi:10.1088/2041-8205/711/2/L138
|
Text
WRAP_Steeghs_HM_Cancri_1003.0658v1.pdf - Accepted Version Download (411Kb) | Preview |
Official URL: http://dx.doi.org/10.1088/2041-8205/711/2/L138
Abstract
HM Cancri is a candidate ultracompact binary white dwarf with an apparent orbital period of only 5.4 minutes, as suggested by X-ray and optical light-curve modulations on that period, and by the absence of longer-period variability. In this Letter, we present Keck-I spectroscopy which shows clear modulation of the helium emission lines in both radial velocity and amplitude on the 5.4 minute period and no other. The data strongly suggest that the binary is emitting He I 4471 from the irradiated face of the cooler, less massive star, and He II 4686 from a ring around the more massive star. From their relative radial velocities, we measure a mass ratio q = 0.50 +/- 0.13. We conclude that the observed 5.4 minute period almost certainly represents the orbital period of an interacting binary white dwarf. We thus confirm that HM Cnc is the shortest period binary star known: a unique test for stellar evolution theory, and one of the strongest known sources of gravitational waves for LISA.
| Item Type: | Journal Article | ||||
|---|---|---|---|---|---|
| Subjects: | Q Science > QB Astronomy | ||||
| Divisions: | Faculty of Science > Physics | ||||
| Library of Congress Subject Headings (LCSH): | Double stars, White dwarf stars | ||||
| Journal or Publication Title: | Astrophysical Journal Letters | ||||
| Publisher: | IOP Publishing Ltd | ||||
| ISSN: | 2041-8205 | ||||
| Official Date: | 10 March 2010 | ||||
| Dates: |
|
||||
| Volume: | Vol.711 | ||||
| Number: | No.2 | ||||
| Number of Pages: | 5 | ||||
| Page Range: | L138-L142 | ||||
| DOI: | 10.1088/2041-8205/711/2/L138 | ||||
| Status: | Peer Reviewed | ||||
| Publication Status: | Published | ||||
| Access rights to Published version: | Restricted or Subscription Access | ||||
| Funder: | United States. National Aeronautics and Space Administration (NASA), W. M. Keck Foundation, Nederlandse Organisatie voor Wetenschappelijk Onderzoek [Netherlands Organisation for Scientific Research] (NWO) | ||||
| Grant number: | 680.50.0610 (NWO), NNX08AK66G (NASA) | ||||
| Related URLs: |
Data sourced from Thomson Reuters' Web of Knowledge
Request changes or add full text files to a record
Repository staff actions (login required)
 |
View Item |
Downloads
Downloads per month over past year
