Orbital periods of cataclysmic variables identified by the SDSS. V. VLT, NTT and Magellan observations of nine equatorial systems

Details Orbital periods of cataclysmic variables identified by the SDSS. V. VLT, NTT and Magellan observations of nine equatorial systems Orbital periods of cataclysmic variables identified by the SDSS. V. VLT, NTT and Magellan observations of nine equatorial systems

2008-09-10

arxiv.org/abs/0809.1753v1

Astronomy and Astrophysics

Astrophysics

Accepted for publication in MNRAS. 17 pages, 20 figures (some with a very pleasant colour scheme), 4 tables

Scientific paper

10.1111/j.1365-2966.2008.13932.x

We present VLT and Magellan spectroscopy and NTT photometry of nine faint cataclysmic variables (CVs) which were spectroscopically identified by the SDSS. We measure orbital periods for five of these from the velocity variations of the cores and wings of their Halpha emission lines. Four of the five have orbital periods shorter than the 2-3 hour period gap observed in the known population of CVs. SDSS J004335.14-003729.8 has an orbital period of Porb = 82.325 +/- 0.088 min; Doppler maps show emission from the accretion disc, bright spot and the irradiated inner face of the secondary star. In its light curve we find a periodicity which may be attributable to pulsations of the white dwarf. SDSS J163722.21-001957.1 has Porb = 99.75 +/- 0.86 min. By combining this new measurement with a published superhump period we estimate a mass ratio of 0.16 and infer the physical properties and orbital inclination of the system. For SDSS J164248.52+134751.4 we find Porb = 113.60 +/- 1.5 min. The Doppler map of this CV shows an unusual brightness distribution in the accretion disc which would benefit from further observations. SDSS J165837.70+184727.4 had spectroscopic characteristics which were very different between the SDSS spectrum and our own VLT observations, despite only a small change in brightness. We measure Porb = 98.012 +/- 0.065 min from its narrow Halpha emission line. Finally, SDSS J223843.84+010820.7 has a comparatively longer period of Porb = 194.30 +/- 0.16 min. It contains a magnetic white dwarf and, with g = 18.15, is brighter than the other objects studied here. These results continue the trend for the fainter CVs identified by the SDSS to be almost exclusively shorter-period objects with low mass transfer rates.

Affiliated with

Also associated with

No associations

Rating

Orbital periods of cataclysmic variables identified by the SDSS. V. VLT, NTT and Magellan observations of nine equatorial systems does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Orbital periods of cataclysmic variables identified by the SDSS. V. VLT, NTT and Magellan observations of nine equatorial systems, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Orbital periods of cataclysmic variables identified by the SDSS. V. VLT, NTT and Magellan observations of nine equatorial systems will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-161320