J/MNRAS/448/2890 Observation of six NSVS eclipsing binaries (Dimitrov+, 2015)
Ultrashort-period main-sequence eclipsing systems: new observations and
light-curve solutions of six NSVS binaries.
Dimitrov D.P., Kjurkchieva D.P.
<Mon. Not. R. Astron. Soc., 448, 2890-2899 (2015)>
=2015MNRAS.448.2890D 2015MNRAS.448.2890D (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Binaries, eclipsing ;
Photometry, VRI ; Photometry, infrared ; Colors
Keywords: binaries: eclipsing - stars: fundamental parameters -
stars: individual: NSVS 925605 - stars: late-type
Abstract:
We carried out photometric and low-resolution spectral observations of
six eclipsing ultrashort-period binaries with main-sequence
(MS)components. The light-curve solutions of the Rozhen observations
show that all targets are overcontact systems. We found a well-defined
empirical relation between period and semi-major axis for the
short-period binaries and used it for estimation of the global
parameters of the targets. Our results revealed that NSVS 925605 is
quite an interesting target: (i) it is one of a few contact binaries
with M components; (ii) it exhibits high activity (emission in the
Hα line, X-ray emission, large cool spots, non-Planck energy
distribution); (iii) its components differ in temperature by 700 K.
All the appearances of high magnetic activity and the huge fill-out
factor (0.7) of NSVS 925605 may be a precursor of the predicted
merging of close magnetic binaries. Another unusual binary is
NSVS 2700153, which reveals considerable long-term variability.
Description:
We managed to separate a sample of about 40 ultrashort-period
candidates from the Northern Sky Variability Survey (NSVS, Wozniak et al.
2004AJ....127.2436W 2004AJ....127.2436W) appropriate for follow-up observations at
Rozhen observatory (δ>-10°). Follow-up CCD photometry of the
targets in the VRI bands was carried out with the three telescopes of
the Rozhen National Astronomical Observatory. The 2-m RCC telescope is
equipped with a VersArray CCD camera (1340x1300 pixels, 20 µm/pixel,
field of 5.35x5.25 arcmin2). The 60-cm Cassegrain telescope is equipped
with a FLI PL09000 CCD camera (3056x3056 pixels, 12 µm/pixel, field
of 17.1x17.1 arcmin2). The 50/70 cm Schmidt telescope has a field of
view (FoV) of around 1° and is equipped with a FLI PL 16803 CCD
camera, 4096x4096 pixels, 9 µm/pixel size.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 67 6 List of our ultrashort-period targets
tablea1.dat 45 42 Colours of the targets and their standard stars
tablea2.dat 33 3641 Rozhen photometric data
tablea3.dat 36 65 Times of the observed eclipse minima
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See also:
I/254 : The HST Guide Star Catalog, Version 1.2 (Lasker+ 1996)
I/305 : The Guide Star Catalog, Version 2.3.2 (GSC2.3) (STScI, 2006)
B/gcvs : General Catalogue of Variable Stars (Samus+, 2007-2017)
J/A+A/528/A90 : SuperWASP short period eclipsing binaries (Norton+, 2011)
J/AcA/65/39 : OGLE Galactic Bulge ultra-short-period binaries
(Soszynski+, 2015)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1 I1 --- Target [1/6] Target NSVS binary (G1)
3- 9 I7 --- NSVS NSVS identifier (NSVS NNNNNNNN in Simbad)
11- 12 I2 h RAh Hour of Right Ascension (J2000)
14- 15 I2 min RAm Minute of Right Ascension (J2000)
17- 21 F5.2 s RAs Second of Right Ascension (J2000)
23 A1 --- DE- Sign of the Declination (J2000)
24- 25 I2 deg DEd Degree of Declination (J2000)
27- 28 I2 arcmin DEm Arcminute of Declination (J2000)
30- 33 F4.1 arcsec DEs Arcsecond of Declination (J2000)
35- 39 F5.2 mag Rmag R-band magnitude
41- 46 F6.4 d Per Period
48- 67 A20 --- Ref Reference (1)
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Note (1): Norton et al. (2011, J/A+A/528/A90).
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Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1 I1 --- Target [1/6] Target NSVS binary (G1)
3- 5 A3 --- Star Star identifier (Var=Variable, St=Standard)
6 A1 --- n_Star [*] Note on Star (1)
8- 17 A10 --- ID GSC1.2 (Cat. I/254, NNNN-NNNN) and GSC2.3
(Cat. I/305, N8BMNNNNNN) identifier
19- 23 F5.2 mag Vmag V-band magnitude
25- 29 F5.2 mag B-V B-V colour index
31- 35 F5.2 mag V-R V-R colour index
37- 40 F4.2 mag V-I V-I colour index
42- 45 F4.2 mag J-K 2MASS J-K colour index
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Note (1): Note as follows:
* = Standard stars used for the observations with the 2-m telescope.
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Byte-by-byte Description of file: tablea2.dat
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Bytes Format Units Label Explanations
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1 I1 --- Target [1/6] Target NSVS binary (G1)
3 A1 --- Filter [VRI] Filter
5- 18 F14.6 d HJD Heliocentric Julian Date
20- 26 F7.4 mag mag Magnitude in Filter
28- 33 F6.4 mag e_mag Uncertainty in mag
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Byte-by-byte Description of file: tablea3.dat
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Bytes Format Units Label Explanations
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1 I1 --- Target [1/6] Target NSVS binary (G1)
3- 16 F14.6 d HJDmin Heliocentric Julian Date of minimum
18 A1 --- Filter [VRI] Filter
20- 21 A2 --- Min [I II] Type of minimum (I=primary, II=secondary)
23- 26 I4 --- Epoch [-1/2189] Epoch
28- 36 F9.6 d O-C Observed minus calculated time of minimum
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Global notes:
Note (G1): Target number as follows:
1 = NSVS 4484038;
2 = NSVS 7179685;
3 = NSVS 4761821;
4 = NSVS 2700153;
5 = NSVS 925605;
6 = NSVS 8626028.
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History:
From electronic version of the journal
(End) Tiphaine Pouvreau [CDS] 28-Nov-2017