BlackCAT A Catalog of Stellar-Mass Black Holes in X-ray Binaries

ID# 15

GS 2023+338

V404 Cyg

RA (h:m:s)  DEC (º:':")  J2000:
20:24:03.82 +33:52:01.90
( Miller-Jones2009 )

Galactic l (º)  b (º)  J2000:
073.1187114  -02.0913251

Year of discovery: 1989  
( Makino1989 )

# of outbursts after discovery: 2

Dynamically confirmed BH

Basic data

Distance (d) 2.39±0.14 (kpc) Miller-Jones2009
d above plane (z) -0.09±0.01 (kpc) Miller-Jones2009
Orbital period 155.311±0.002 (h) Casares1992 Wagner1992a Casares1994
Peak X-ray flux 2.59E-07
(erg/s/cm2) [keV] Zycki1999
Outburst magnitude (AB) V∼11.7 (mag) Casares1991
Quiescent magnitude (AB) R=16.58±0.01 (mag) Casares1993 Zurita2004 Casares1993 Zurita2004
E(B-V) 1.3 (mag) Casares1993
Notes GS 2023+338 (V404 Cyg) showed two outbursts detected in plate scales (1938 and 1956) prior to its detection in X-rays in 1989 ( Wachmann1948 , Richter1989 ). It has shown two new outbursts in 2015 ( Barthelmy2015 , Barthelmy2015a ).

Dynamical parameters

Orbital period 155.311±0.002 (h) Casares1992 Wagner1992a Casares1994
Star's spectral type K3III Casares1993 Khargharia2010
Star's radial velocity amplitude (K2) 208.5±0.7 (km/s) Casares1994
Mass function 'f(M1)' 6.08±0.06 (M) Casares1992 Casares1994
BH mass (M1) 9+0.2-0.6 (M) Khargharia2010
Mass ratio (q=M/M1) 0.067±0.005 Casares1994 Casares1996
Inclination angle (i) 67+3-1 (deg) Khargharia2010
Rot. broadening (v sini) 39±1 (km/s) Casares1994

Optical/NIR magnitudes

Mag. Outburst (AB) Casares1991
Mag. Quiescence (AB) Casares1993 Zurita2004 Casares1993 Zurita2004
=16.58±0.01 =18.38±0.02 =20.47±0.05 =16.07±0.05 =14.59±0.08
H Ks
=14.21±0.06 =14.39±0.05
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GS 2023+338 in Simbad
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Object marked with lines

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This research has made use of NASA's Astrophysics Data System (ADS) and the SIMBAD database operated at CDS (Strasbourg, France)
Please acknowledge the use of this catalogue in any published work you derive from it.