IGR J17473-2721

Other name = XTE J1747-274

Type Distance Radio Counterpart Infrared/Optical Counterpart
R.A. (J2000) Dec. (J2000) References R.A. (J2000) Dec. (J2000) References
Neutron star-LMXB
5.5+- 0.8 kpc 17h 47m 18.08s -27° 20' 38.7" Juett et al. 2005 Atel 521
Published Papers
Miscellaneous :

Kennea et al. 2005 (Atel 500):
  • NH~5.2 x 1022 cm-2
  • Gamma~2.12
  • F0.5-10 keV=8.4 x 10-10 erg/s/cm2
Juett et al. 2005 (Atel 521):
  • Ks=16.2
  • Not a obscured HMXB
  • Magellan I/PANIC image available here (courtesy A.M. Juett)
Torres et al. 2005 (Atel 634):
  • Confirm that candidate proposed by Juett et al, 2005 (ATel 521), is indeed the NIR counterpart.
  • This counterpart has dimmed (not detected at 3-sigma upper limit magnitude of Ks>17.4).
Del Monte et al. 2008 (Atel 1445):
  • Detection of a burst with the super Agile detector onboard AGILE
  • The burst detected on 26 March 2008, 23:19:40 UT, and lasted ~40 s, significant only in the energy range 17-25 keV.
  • For d~8.5 kpc, the 17-25 keV luminosity~ 0.9e38 erg/s=> consistent with an Eddington limited flux for a neutron star mass.
  • Burst is a Type I X-ray burst => IGR J17473-2721 is an X-ray burster
Altamirano et al. 2008 (Atel 1459):
  • XRT observation => X-ray position consistent with the Chandra
  • Confirms the association with the detection of a type I burst by Agile.
  • XRT spectrum well fitted by an absorbed power law with Γ=1.68 and NH=3.8e22cm-2.
  • Detection of a 100s long X-ray burst, black body of 2.3 keV, no photospheric radius expansion
  • Upper limit to the distance between 3.9 and 5.4 kpc.
Markwardt et al. 2008 (Atel 1460):
  • RXTE monitoring scan => persistent activity on 2008-03-28 and 2008-03-31 at 2-10 keV fluxes of about 13 and 18 mCrab.
  • Previous scans consistent with quiescent level with 2 sigma upper limit of 6 mCrab.
Kuulkers et al. 2008 (Atel 1461):
  • INTEGRAL/ISGRI detection during Galactic bulge monitoring.
  • 18-40 keV and 40-80 keV fluxes of 41 mCrab and 42 mCrab respectively => hard spectral state.
  • Previous observation (2008 March 22): source possibly seen near detection limit :6.5 mCrab (18-40 keV).
  • Images and details can be found at http://isdc.unige.ch/Science/BULGE/ (courtesy Erik Kuulker).
Baldovin Saavedra et al. 2008 (Atel 1468):
  • Source flux has increased by a factor of 3 in 8 days
  • Detected by ISGRI up to 250 keV. 20-250 keV flux 2.7 10-9 erg/cm2/s
  • 50s long X-ray burst detected, with 0.1-100 keV flux 3.7 10-8 erg/cm2/s, with a BB of kT=2.4 keV
Altamiraino et al. 2008 (Atel 1651):
  • RXTE monitoring, maximum reached unabsorbed flux of ~1.30E-8 ergs cm-2 s-1 (2-10 keV, with nH=3.8e22cm-2) on June 22nd 2008
  • Switch from hard state to soft state and back during outburst
  • During the soft state: 6 observations show a kHz QPO at frequency up to ~900 Hz, reaching up to 8% rms => neutron star atoll sources.
  • 16 type-I X-ray bursts, 2 with photospheric radius expansion =>distance between 4.9-5.7 kpc.
Zhang et al. 2009 (A&A):
  • Swift and RXTE observations of 2 periods of outbursts
  • Outburst separated in different sequences. Spectral analysis of these.
  • State transition hard state->soft state-> hard state showing an hysteresis
  • Discussion of the origin of state evolution
Chen et al. 2010 (A&A):
  • RXTE analysis of Type I X-ray bursts from 2 outbursts
  • 18 bursts, 3 of which show photospheric radius expansion => distance 6.4 kpc (15% error).
  • Duration of bursts correlated L/LEdd
  • End of the most recent outburst: profile of the bbody radius anticorrelated with the bbody temperature
  • Discussion in the context of type I bursts in LXMB and Atoll sources in general
Chenevez et al. 2011 (MNRAS):
  • RXTE, Swift, INTEGRAL, Agile observations => total of 57 thermonuclear bursts during 2008 ouburst
  • Study of spectral and temporal properties of all bursts, and study the bursting behaviour and burst properties
  • Burst rate first increases with the accretion rate until it stops. It resumes at a much lower accretion rate =>Hysteresis whose origin is discussed
  • Occurrence of a (missed) super burst as the origin of the quenching of bursting activity
  • Some bursts identified as photospheric radius expansion bursts=> distance to the source of 5.5±0.8 kpc
  • 7 phases of burst behaviour<=> 4 burst regimes: Mixed H/He flashes, pure He flashes (with stable H burning), rich He flashes at low dot(m) and no burst ie stable H and He burning.
Chen et al. 2011 (A&A):
  • RXTE, Swift, INTEGRAL, observations
  • Study relation between duration of types I X-ray bursts and source flux
    => confirm the correlation seen in other sources
    =>Slope of the correlation differs between the increasing and decaying part of outburst
  • Cut-off energy of X-ray spectra decreases from quiescence to and through the hard state => cooling of the coronal electrons by soft photons coming either from the disc or the NS surface
  • Corona sits on top of the disc rather than on the NS surface

Last updated. 8 Sept 2011

Jerome Rodriguez