IGR J16393-4643


Other name = AX J1639.0-4642

Type Orb P. / Spin P. Radio Counterpart Infrared Counterpart
R.A. (J2000) Dec. (J2000) References (position) R.A. (J2000) Dec. (J2000) References (position)
HMXB favoured
Symbiotic system (controversial)
4.2 d / 904 s
Published Papers
Miscellaneous :
Fillipova et al. 2005:
  • NH = 5.8 x 1023 cm-2
  • Gamma=1.3+/-1.0
  • Ecut=11+/-1 keV
Bodaghee et al. 2006:
  • Persistent, heavily-absorbed, wind-accreting pulsar
  • NH = 2.5 x 1023 cm-2
  • Pulse period = 912.0+/-0.1 s
  • Gamma = 0.8+/-0.2
  • Ecut = 10+/-1 keV
  • Iron lines at 6.4 and 7.1 keV, with an absorption edge > 7.1 keV
  • Soft excess emission
  • Continuum modeled by absorbed comptt or an absorbed cutoff power law
  • Spectral shape not modified by pulse
  • Crowded field => 3EG association might be due to chance
Thompson et al. 2006: ATel 786
  • Orbital period from RXTE data is 3.688+/-0.001 days.
  • This implies a stellar mass of 6.5+/-1.1 solar masses.
Thompson et al. 2006, ApJ:
  • Orbital period from RXTE data is 3.6875+/-0.0006 days.
  • pulse period of 911.3 s => may imply spin up since measure by Bodaghee et al. 2005
Chaty et al. 2008:
  • Optical and infrared observations
  • 3 additional counterparts to 2MASS source, however 2MASS considered as the likely candidate
  • B>24.97, V=21.53, R=19.62, I=17.92, Z=16.99
  • J=17.24, H=13.28, Ks=11.21
  • SED fitting => Tstar=24400 K, typical of B star
  • SED fitting => d=10.6 kpc for a BIV-V star, and 20.4kpc at least for a supergiant. BIV-V favoured
Nespoli et al. 2008: ATel 1450
  • Prominent CO absorption features between 2.29 and 2.40 Ám, <=> late type stars.
  • Presence of metallic lines.
  • Presence of He I 20581 A and Br-gamma =>circumstellar disk around a compact object, but warning is given
  • HXMB ruled out, companion very probablyof K or M spectral type => system is Symbiotic X-ray binaries
Nespoli et al. 2010 (A&A):
  • Prominent CO absorption features => late type stars.
  • HXMB ruled out, companion very probably K or M Giant/Supergiant => system is Symbiotic X-ray binaries
  • Select mass function of 0.092 Msun and orbit of 52 days.
  • Companion mass < 5 Msun
  • All conclusions valid if the counterpart considered is the true one
Corbet et al. 2010 ATel 2570:
  • Swift/BAT and RXTE/PCA monitoring
  • None of the previously reported period in the long term light curves.
  • Highly significant modulation at 4.2 days in both light curves.
  • fits with sine wave to the LCs
    Tmax (BAT) = MJD 54,352.50 (+/- 0.09) + n x 4.2368 (+/- 0.0007)
    Tmax (PCA) = MJD 54,352.39 (+/- 0.11) + n x 4.2371 (+/- 0.0007)
  • Semi-amplitude of the modulation divided by the mean flux is approximately 25%.
  • Modulation likely being orbital period of the system
  • Source lies in the Sg-HMXB region of the Corbet diagram =>IGR J16393-4643 very probably sg HMXB
  • Not a symbiotic system.
Bodaghee et al. 2012 (ApJ):
  • Chandra observation => refined X-ray position
  • 2MASS J16390535-4642137 excluded as IR counterpart
  • New candidate IR counterpart blended with the 2 MASS star
  • Large distance (>12 kpc) to the source suggested
Corbet & Krimm 2013 (ApJ):
  • Search for periodicities in BAT light curves
  • possible identification of a super orbital period due to coincidence of peaks from the BAT, RXTE, INTEGRAL light curves
  • possible Super orbital period at 14.98 days
Islam et al. 2015 (MNRAS):
  • SUzaku broad band pulsation and spectral analysis
  • Swift light curve => evidence for an eclipsing system
  • Short eclipse semi-angle ~ 17o
  • Change of photon index during high and low phase of pulse
Bodaghee et al. 2016 (ApJ):
  • Nustar+Swift observations
  • Discovery of a cyclotron resonant scattering feature @ 29.3 keV
  • B~2.5e12 G
  • Neutron star spin period measured at 904 s => dν/dt=3 e-14 Hz
  • Addition of angular momentum either due to accretion of quasi spherical wind or transient appearance of accretion disk

Last updated 4 April 2016

Jerome Rodriguez