Difference between revisions of "GRO J1744-28"

From Remeis-Wiki
Jump to navigation Jump to search
(GRO J1744-28 - The Bursting Pulsar)
 
Line 8: Line 8:
 
= Type =  
 
= Type =  
 
Transient Low-mass X-ray Binary exhibiting Type I and II X-ray bursts and pulsations. Next to the Rapid Burster this is one of a few sources where Type II bursts are observed.
 
Transient Low-mass X-ray Binary exhibiting Type I and II X-ray bursts and pulsations. Next to the Rapid Burster this is one of a few sources where Type II bursts are observed.
−
Discovered on 1995 December 2 with the Burst And Transient Source Experiment (BATSE) on-board the Compton Gamma Ray Observatory (Kouveliotou et al. 1996)
+
Discovered on 1995 December 2 with the Burst And Transient Source Experiment (BATSE) on-board the Compton Gamma Ray Observatory (<ref name="Kouveliotou96A"/>)
  
 
= Coordinates =  
 
= Coordinates =  
Line 17: Line 17:
  
 
* Distance: 7.5-8.5 kpc (<ref name="Augusteijn97"/>, <ref name="Nishiuchi99"/>)
 
* Distance: 7.5-8.5 kpc (<ref name="Augusteijn97"/>, <ref name="Nishiuchi99"/>)
−
* Optical companion: G4 III star (<ref name="MillerJones07"/>, <ref name="Masetti14"/>)
+
* Optical companion: G4 III star (<ref name="Gosling07A"/>, <ref name="Masetti14Atel"/>) with M<0.4M_sun and inclination i>15° (<ref name="Gosling07A"/>)
  
 
== Orbit ==
 
== Orbit ==
  
−
The orbital parameters were approximated to Porb = 11.836 days, T π/2 = 2456696.19880 (JED), ax sin(i) = 2.637 light-sec on the basis of the 2014 outburst with no constrains on the longitude of periastron or eccentricity (<ref name="Pintore14"/>).
+
The orbital parameters were approximated to Porb = 11.836 days, T π/2 = 2456696.19880 (JED), ax sin(i) = 2.637 light-sec on the basis of the 2014 outburst with no constrains on the longitude of periastron or eccentricity (<ref name="Pintore14Atel"/>).
 
See [https://gammaray.msfc.nasa.gov/gbm/science/pulsars/lightcurves/groj1744.html NSSTC Gamma Ray Astrophysics].
 
See [https://gammaray.msfc.nasa.gov/gbm/science/pulsars/lightcurves/groj1744.html NSSTC Gamma Ray Astrophysics].
  
Line 28: Line 28:
  
 
GRO J1744-28 is special because it exhibits X-ray bursts and pulsations at the same time. Sources which show X-ray bursts are generally believed to have surface conditions (low B-fields) which do not allow pulsations.
 
GRO J1744-28 is special because it exhibits X-ray bursts and pulsations at the same time. Sources which show X-ray bursts are generally believed to have surface conditions (low B-fields) which do not allow pulsations.
−
Pulse period: 2.14Hz <ref name="Finger96"/>
+
Pulse period: 2.14Hz <ref name="Finger96A"/>
  
−
The magnetic field strength deduced from disk reflection models lies in the 2–6×10^10 G range (Degenaar et al. 2014), mismatching the values deduced from the CRSF measurements (5.27±0.06 × 10^11 G <ref name="DAi15"/>) by one order of magnitude.
+
The magnetic field strength deduced from disk reflection models lies in the 2–6×10^10 G range (Degenaar et al. 2014), mismatching the values deduced from the CRSF measurements (5.27±0.06 × 10^11 G <ref name="DAi15A"/>) by one order of magnitude.
  
  
 
== Outbursts ==
 
== Outbursts ==
  
−
* 1995 December: Discovery and first report of Type II X-ray bursts (<ref name="Finger96"/>)
+
* 1995 December: Discovery and first report of Type II X-ray bursts (<ref name="Finger96A"/>)
−
* 1996 December: Similar burst characteristics (<ref name="Woods99"/>), CRSF report at 5keV in BeppoSAX data (not yet proven) (<ref name="Doroshenko15"/>)
+
* 1996 December: Similar burst characteristics (<ref name="Woods99"/>), CRSF report at 5keV in BeppoSAX data (not yet proven) (<ref name="Doroshenko15A"/>)
−
* 2014 February: Outburst after 18 years of quiescence (<ref name="Younes15"/>, no CRSF), CRSF report at 5keV, 10keV and 15keV in XMM-Newton/INTEGRAL data, still under debate (<ref name="DAi15"/>)
+
* 2014 February: Outburst after 18 years of quiescence (<ref name="Younes15"/>, no CRSF), CRSF report at 5keV, 10keV and 15keV in XMM-Newton/INTEGRAL data, still under debate (<ref name="DAi15A"/>)
 
* 2017 February: Fourth outburst with ~two orders of magnitude lower luminosity (Koenig et al. in prep.)
 
* 2017 February: Fourth outburst with ~two orders of magnitude lower luminosity (Koenig et al. in prep.)
  
Line 44: Line 44:
 
=== Cyclotron Features ===
 
=== Cyclotron Features ===
  
−
D’Aì et al. (2015) reported a fundamental CRSF line at 4.68±0.05 keV, with the indication of a second and third harmonic at 10.4 ± 0.1 keV and 15.8+1.3−0.7 keV in XMM-Newton/INTEGRAL data (using gabs).
+
* Fundamental CRSF at 4.68±0.05 keV (gabs, XMM-Newton/INTEGRAL, 2014 outburst <ref name="DAi15A"/>) / ∼4.5 keV (gabs, BeppoSAX, 1997 outburst <ref name="Doroshenko15A"/>)
−
Shortly later, Doroshenko et al. (2015) claim to have found a fundamental line at ∼4.5 keV in BeppoSAX data taken during the 1997 outburst (also using gabs).  (<ref name="DAi15"/>, <ref name="Doroshenko15"/>)
+
* Indication of second and third harmonic at 10.4±0.1 keV and 15.8+1.3−0.7 keV in XMM-Newton/INTEGRAL data (using gabs) (<ref name="DAi15A"/>)
−
This makes GRO J1744−28 one of the few LMXBs where a CRSF has been reported below 10 keV.
+
* GRO J1744−28 one of the few LMXBs where a CRSF has been reported below 10 keV (Other candidates are X1822−371 with a claimed cyclotron line energy of 0.7 keV (<ref name="Iaria15A"/>) and SWIFT J0051.8−7320 at 5 keV (<ref name="Maitra18A"/>)
−
(Other candidates are X1822−371 with a claimed cyclotron line energy of 0.7 keV (Iaria et al. 2015) and SWIFT J0051.8−7320 at 5 keV (Maitra et al. 2018)).
+
* Cyclotron line in this source is under debate
−
)
 
−
The cyclotron line in this source is under debate.
 
  
  
 
'''References'''
 
'''References'''

Revision as of 14:28, 26 September 2019


Other names : 2EG J1746-2852 ([1])

Monitoring data: Swift/BAT

Type

Transient Low-mass X-ray Binary exhibiting Type I and II X-ray bursts and pulsations. Next to the Rapid Burster this is one of a few sources where Type II bursts are observed. Discovered on 1995 December 2 with the Burst And Transient Source Experiment (BATSE) on-board the Compton Gamma Ray Observatory ([1])

Coordinates

RA 17h 44‘ 33.09“ DEC -28° 44‘ 27.0“

Binary system

  • Distance: 7.5-8.5 kpc ([2], [3])
  • Optical companion: G4 III star ([4], [5]) with M<0.4M_sun and inclination i>15° ([4])

Orbit

The orbital parameters were approximated to Porb = 11.836 days, T π/2 = 2456696.19880 (JED), ax sin(i) = 2.637 light-sec on the basis of the 2014 outburst with no constrains on the longitude of periastron or eccentricity ([6]). See NSSTC Gamma Ray Astrophysics.


Pulsations & Magnetic field

GRO J1744-28 is special because it exhibits X-ray bursts and pulsations at the same time. Sources which show X-ray bursts are generally believed to have surface conditions (low B-fields) which do not allow pulsations. Pulse period: 2.14Hz [7]

The magnetic field strength deduced from disk reflection models lies in the 2–6×10^10 G range (Degenaar et al. 2014), mismatching the values deduced from the CRSF measurements (5.27±0.06 × 10^11 G [8]) by one order of magnitude.


Outbursts

  • 1995 December: Discovery and first report of Type II X-ray bursts ([7])
  • 1996 December: Similar burst characteristics ([9]), CRSF report at 5keV in BeppoSAX data (not yet proven) ([10])
  • 2014 February: Outburst after 18 years of quiescence ([11], no CRSF), CRSF report at 5keV, 10keV and 15keV in XMM-Newton/INTEGRAL data, still under debate ([8])
  • 2017 February: Fourth outburst with ~two orders of magnitude lower luminosity (Koenig et al. in prep.)

X-ray Spectrum

Cyclotron Features

  • Fundamental CRSF at 4.68±0.05 keV (gabs, XMM-Newton/INTEGRAL, 2014 outburst [8]) / ∼4.5 keV (gabs, BeppoSAX, 1997 outburst [10])
  • Indication of second and third harmonic at 10.4±0.1 keV and 15.8+1.3−0.7 keV in XMM-Newton/INTEGRAL data (using gabs) ([8])
  • GRO J1744−28 one of the few LMXBs where a CRSF has been reported below 10 keV (Other candidates are X1822−371 with a claimed cyclotron line energy of 0.7 keV ([12]) and SWIFT J0051.8−7320 at 5 keV ([13])
  • Cyclotron line in this source is under debate


References

  1. ↑ Kouveliotou et al., 1996, Nature, Volume 379, Issue 6568, pp. 799-801 (1996) (NASA ADS)
  2. ↑ Augusteijn, T. & Greiner, J., et al., 1997, ApJ 486, 1013 (NASA ADS)
  3. ↑ Nishiuchi, M. et al., 2018, ApJ, Vol. 517, Issue 1, pp. 436-448. (NASA ADS)
  4. ↑ 4.0 4.1 MNRAS, Vol. 380, Issue 4, pp. 1511-1520. (NASA ADS)
  5. ↑ Masetti et al., ATel, No.5999, March 2014 (NASA ADS)
  6. ↑ Pintore, F. et al., ATEL, No.5901, Feb 2014 (ATEL)
  7. ↑ 7.0 7.1 Finger, M. H. et al., Nature, Volume 381, Issue 6580, pp. 291-293 (1996) (NASA ADS)
  8. ↑ 8.0 8.1 8.2 8.3 D'Ai, A. et al., MNRAS, Volume 449, Issue 4, p.4288-4303 (NASA ADS)
  9. ↑ Woods, P. M. et al., ApJ, Vol. 517, Issue 1, pp. 431-435 (NASA ADS)
  10. ↑ 10.0 10.1 Doroshenko et al., 2015, Monthly Notices of the Royal Astronomical Society, Volume 452, Issue 3, p.2490-2499 (NASA ADS)
  11. ↑ Younes, G. et al, ApJ, Vol. 804, Issue 1, article id. 43, 16 pp. (2015) (NASA ADS)
  12. ↑ Iaria et al., 2015, A&A, Volume 577, id.A63, 14 pp. (NASA ADS)
  13. ↑ Maitra et al., 2018, Monthly Notices of the Royal Astronomical Society: Letters, Volume 480, Issue 1, p.L136-L140 (NASA ADS)
Retrieved from "https://www.sternwarte.uni-erlangen.de/wiki/index.php?title=GRO_J1744-28&oldid=1890"