IGR J16328-4726

Other name = (?)

Type Orb. Period Radio Counterpart Infrared/Optical Counterpart
R.A. (J2000) Dec. (J2000) References R.A. (J2000) Dec. (J2000) References
O8Iafpe companion
10.076 d 16h 32m 37.91s -47o 23' 40.9" Grupe et al. ATel 2075
Published Papers
Miscellaneous :
Grupe et al. 2009 ATel 2075:
  • Swift observations during a flare
  • steadily decaying over the first orbit of observation
  • Spectrum fitted with an absorbed power law with Γ=0.56 and NH=8.1 x 1022 cm-2
  • No USNO-B1 counterparts, but one 2MASS counterpart with J=14.631, H=12.423, K=11.275.
Corbet et al. 2010 ATel 2588:
  • ~10 day period in long term Swift/BAT (15-100 keV) light curve
  • Source mean flux ~1.3 mCrab light curve fitted with a sine wave
    Tmax (MJD) = 54,256.08 + n x 10.076
    Tmax is the time of maximum flux, with a 100% flux modulation
  • No pulsation at shorter period when lookin at an XRT light curve with 5s resolution
  • 10 d period interpretred as orbital period=> HMXB
  • Source is intrinsically absorbed consistent with HMXB powered by wind accretion
Fiocchi et al. 2010:
  • Analysis of 10 Ms of ISGRI light curve data
  • Quiescent emission < 2.5 × 10-12 erg/s/cm^2
  • Two strong outbursts detected: on 19 February, 2005 (53420.65 MJD), lasting about 1 hour; and the second on 28 January, 2009 (54859.99 MJD), lasting about 3.5 hours.
  • Several smaller outbursts (4-5 sigma) lasting several minutes to hours also reported
  • All show similar spectral shapes in the ISGRI range, only normalisation changes
  • 2MASS J16323791-4723409 as the most likely candidate counterpart in the IR.
  • With a dynamic range of over 170 + sporadic emission behavior conclude that IGR J16328-4726 is a new member of the class of SFXTs.
Bozzo et al. 2012 (A&A):
  • XMM-Newton observation
  • Spectral analysis
  • Source is an SFXT
Fiocchi et al. 2012 :
  • Analysis of INTEGRAL and Beppo-SAX observations
  • Confirm that the source is an SFXT with an OB type companion
  • Assuming a clump as the origin of an observed flare => a mass of 4e22g and a radius of 4.4E6 km for the clump
Coleiro et al. (2013) :
  • NTT/Sofi NIR Spectroscopy
  • Several lines in spectra among which Br(7-4), N III, CIII in emission and He I in absorption
  • O8 Iaf or more probably O8 Iafpe companion
Romano et al. 2014(A&A):
  • Study of long term Swift/XRT monitoring
  • Behaviour similar to other SFXTs with 61% inactivity duty cycle, and a dynamic range of ~750 during bursts
  • Probably intermediate SFXT (lower duty cycle compared to other members of this class)
  • No correlation between duty cycle and orbital period

Last updated 4 March 2015

Jerome Rodriguez