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Details for Revision 3
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Name
V1521 Cyg
AAVSO UID
000-BDP-365 (1
observation
)
Constellation
Cygnus
Sequence
J2000.0
20 32 25.78 +40 57 27.9 (308.10742 +40.95775)
Search nearby
B1950.0
20 30 37.69 +40 47 12.5
Galactic coord.
79.845 +0.700
Other names
(Internal only)
1RXS J203226.2+405725
2MASS J20322578+4057279
4U 2030+40
Cyg X-3
X 20305+407
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Variability type
HMXB
Spectral type
WN4/5-6/7
Mag. range
11.4 (1.53) K
Discoverer
--
Epoch
--
Outburst
--
Period
0.1996907 d (4.79258 h)
Rise/eclipse dur.
--
Remarks
Some references may be clicked to view in new window. Roll over index number to view submission details.
1
Otero, Sebastian Alberto
Microquasar.
2
GCVS Team
Cyg X-3. Peculiar infrared X-ray source. V > 23m. Flare radio source. In the K band short and slow flares on the time scale about 2 minutes and 1-2 hours, irregular variations and longperiodic variability are observed [
E.E.Becklin, F.J.Hawkins, K.O. Mason, K.Matthews, G.Neugebauer, D.Packman, P.W.Sanford, B.Schupler, A.Stark, C.G.Wynn- Williams, ApJ 192, L 119, 1974.
]. These variations are accompanied by periodical oscillations of infrared, X-ray and gamma radiation with the elements: Min = 2440949.8986 + 0.1996830d*E + 1.25d*10**(-10)*E**2 [
M. van der Klis, J.M.Bonnet-Bidaud, AsAp 95, L5, 1981.
]. Usually the amplitude of these variations A(K) = 0.5m, but sometimes they disappear completely.
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References
Click reference title/citation to view in new window. Roll over index number to view submission details.
1
Corral-Santana, J. M.; Casares, J.; Muņoz-Darias, T.; et al., 2016,
WATCHDOG: A Comprehensive All-sky Database of Galactic Black Hole X-ray
Binaries
2016ApJS..222...15T
2
A description of sources detected by INTEGRAL during the first 4 years of
observations
2007A&A...467..585B
3
A description of sources detected by INTEGRAL during the first 4 years of
observations
2007A&A...467..585B
4
Catalogue of Stellar Spectral Classifications (Skiff, 2005)
1996A&A...314..521V
5
T.C.Weekes, J.G.Geary, PASP 94, 708, 1982.
1982PASP...94..708W
6
M.Milgrom, D.Pines, ApJ 220, N1, 272, 1978.
1978ApJ...220..272M
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Supporting Documents
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Revision History
Currently approved revision is checked. Click revision number to view details of that revision.
4
Otero, Sebastian Alberto
2018-02-28 02:56 UTC
Spectral type from
2016ApJS..222...15T
. 2MASS position.
3
Otero, Sebastian Alberto
2011-05-25 01:39 UTC
Primary record creation. Orbital period from reference. Type from Liu et al. (
2006A&A...455.1165L
).
2
Admin, VSX
2007-04-04 09:53 UTC
Position and spectral type from Brian Skiff's MKTypes.dat [http://vizier.u-strasbg.fr/viz-bin/Cat?III/233B].
1
Admin, VSX
2005-12-18 01:33 UTC
Initial database population.
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