Access to Astronomical Catalogues

← Click to display the menu
J/AJ/153/238               Mid-eclipse times of DV UMa              (Han+, 2017)

Cyclic period oscillation of the eclipsing dwarf nova DV UMa. Han Z.-T, Qian S.-B, Irina V., Zhu L.-Y <Astron. J., 153, 238-238 (2017)> =2017AJ....153..238H (SIMBAD/NED BibCode)
ADC_Keywords: Binaries, eclipsing Keywords: binaries: close - binaries: eclipsing - stars: dwarf novae - stars: individual: DV UMa Abstract: DV UMa is an eclipsing dwarf nova with an orbital period of ∼2.06hr, which lies just at the bottom edge of the period gap. To detect its orbital period changes, we present 12 new mid-eclipse times by using our CCD photometric data and archival data. The latest version of the O-C diagram, combined with the published mid-eclipse times in quiescence, and spanning ∼30 years, was obtained and analyzed. The best fit to those available eclipse timings shows that the orbital period of DV UMa is undergoing a cyclic oscillation with a period of 17.58(±0.52) years and an amplitude of 71.1(±6.7) s. The periodic variation most likely arises from the light-travel-time effect via the presence of a circumbinary object, because the required energy to drive the Applegate mechanism is too high in this system. The mass of the unseen companion was derived as M3sini'=0.025(±0.004)M. If the third body is in the orbital plane (i.e., i'=i=82.9°) of the eclipsing pair, this would indicate it is a brown dwarf. This hypothetical brown dwarf is orbiting its host star at a separation of ∼8.6 au in an eccentric orbit (e=0.44). Description: New CCD photometric observations of DV UMa were carried out by using three different telescopes. Beginning on 2009 November 12, this star was continuously monitored with the 2.4m telescope at the Lijiang observational station of Yunnan Observatories (YNAO). To collect more data for this binary, an observation was made on 2016 March 29 with an Andor DW436 1K CCD camera mounted on the 85cm reflecting telescope at the XingLong station of the National Astronomical Observatory and another observation made on 2017 January 23 with an Andor DW936 2K CCD camera attached to the 1.0m reflecting telescope at YNAO. During the observations, no filters were used in order to improve the time resolution. Objects: ---------------------------------------------------------- RA (ICRS) DE Designation(s) ---------------------------------------------------------- 09 46 36.65 +44 46 45.1 V* DV UMa = US 943 ---------------------------------------------------------- File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 56 112 All mid-eclipse times of DV UMa
See also: B/gcvs : General Catalogue of Variable Stars (Samus+ 2007-2013) Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 13 F13.5 d HJD Heliocentric Julian Date of minimum light 15- 20 I6 --- E [1/127225] Epoch number 22- 30 F9.6 d O-C The (O-C) residual 32- 38 F7.5 d e_O-C Error in O-C 40- 49 A10 --- State State (outburst or quiescence) 51- 54 A4 --- Tel Telescope (1.0m, 2.4m, 85cm) 56 I1 --- Ref Reference (1)
Note (1): Reference codes are defined as follows: 1 = Howell et al. (1988MNRAS.233...79H); 2 = Nogami et al. (2001MNRAS.322...79N); 3 = Patterson et al. (2000PASP..112.1584P); 4 = Feline et al. (2004MNRAS.355....1F); 5 = American Association of Variable Star Observers (AAVSO) data; 6 = Our observations.
History: From electronic version of the journal
(End) Sylvain Guehenneux [CDS] 10-Aug-2017
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

catalogue service