SIMBAD references

2009A&A...497..437R - Astronomy and Astrophysics, volume 497, 437-444 (2009/4-2)

CURious Variables Experiment (CURVE): CCD photometry of active dwarf nova DI Ursae Majoris.


Abstract (from CDS):

We report an analysis of photometric behaviour of DI UMa, an extremely active dwarf nova. The observational campaign (completed in 2007) covers five superoutbursts and four normal outbursts. We examined principal parameters of the system to understand peculiarities of DI UMa, and other active cataclysmic variables. Based on precise photometric measurements, temporal light curve behaviour, O-C analysis, and power spectrum analysis, we investigated physical parameters of the system. We found that the period of the supercycle now equals 31.45±0.3days. Observations during superoutbursts infer that the period of superhumps equals P_ sh_=0.055318(11)days (79.66±0.02min). During quiescence, the light curve reveals a modulation of period Porb=0.054579(6) days (78.59±0.01min), which we interpret as the orbital period of the binary system. The values obtained allowed us to determine a fractional period excess of 1.35%±0.02%, which is surprisingly small compared to the usual value for dwarf novae (2%-5%). A detailed O-C analysis was performed for two superoutbursts with the most comprehensive coverage. In both cases, we detected an increase in the superhump period with a mean rate of {dot}(P/P)sh=4.4(1.0)x10–5. Based on these measurements, we confirm that DI UMa is probably a period bouncer, an old system that reached its period minimum a long time ago, has a secondary that became a degenerate brown dwarf, the entire system evolving now toward longer periods. DI UMa is an extremely interesting object because we know only one more active ER UMa star with similar characteristics (IX Dra).

Abstract Copyright:

Journal keyword(s): stars: individual: DI Ursae Majoris - stars: dwarf novae - stars: novae, cataclysmic variables - stars: binaries: close

VizieR on-line data: <Available at CDS (J/A+A/497/437): table1.dat table2.dat>

Simbad objects: 5

goto Full paper

goto View the reference in ADS

To bookmark this query, right click on this link: simbad:2009A&A...497..437R and select 'bookmark this link' or equivalent in the popup menu


© Université de Strasbourg/CNRS

    • Contact