IGR J16320-4751

Other name = AX J1631.9-4752

Type Spectral Type Radio Counterpart Infrared Counterpart
R.A. (J2000) Dec. (J2000) References (position) R.A. (J2000) Dec. (J2000) References (position)
pulsar, HMXB
supergiant XRB
BN0.5 Ia 2MASS K image here
16h 32m 01.75s -47° 52' 28.9"
Published Papers
Miscellaneous :
Rodriguez et al. 2003: NH=2.1 x 1023 cm-2
Lutovinov et al. 2005: Soft X-ray pulsations at 1309 +-40s in XMM, and 1295 +-50 s in ASCA
Corbet et al. 2005: Orbital period of 8.96+/-0.01 days in Swift/BAT (ATel #649)
Rodriguez et al. 2006:
  • Confirm the presence of X-ray pulsations at ~1300 s, detected above 20 keV with INTEGRAL
  • Pulse fraction = constant with energy, <=> model of polar accretion by a pulsar
  • Phase resolved spectroscopy =>, pulse solely due to variations of X-ray flux & not to variations of spectral parameters
  • Soft excess (blackbody) with kT~0.07 keV
  • Narrow iron line at ~6.4 keV
  • Hard X-rays = Compton emission from close vicinity of pulsar
  • Soft excess = emission by a collisionally energised cloud in which compact object is embedded
Negueruela & Schurch 2006:
  • 2MASS J16320215-4752289 is indeed the counterpart
  • if OB supergiant then extremely reddened
Chaty et al. 2008:
  • Optical and infrared observations
  • B>22.8, V>24.7, R>22.1, I>22.3, Z>21.7
  • J=17.24, H=13.28, Ks=11.21
  • Very red Near IR spectrum with absorption and emission lines
  • The brackett serie has a P-Cygni profile=>luminous OB sg
Rahoui et al. 2008:
  • Medium infrared observations
  • SED fitting => AV=35.4, Tstar=33000 K => O8 I
  • Obscuring material contributes little to MIR spectrum
  • Suggested distance 3.5 kpc
Coleiro et al. (2013) :
  • NTT/Sofi NIR Spectroscopy
  • Br(7-4) clearly detected with a possible P-Cygni profile. Faint broad He I emission, and another in absorption
  • Several absorption lines not associated with physiocal transitions in spectrum
  • Stellar companion is a BN0.5 Ia star

Last updated 10 October 2013

Jerome Rodriguez