Difference between revisions of "GRO J1744-28"
Jump to navigation
Jump to search
| Line 2: | Line 2: | ||
'''Other names''' : 2EG J1746-2852 ([http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=GRO+J1744-28&submit=SIMBAD+search]) | '''Other names''' : 2EG J1746-2852 ([http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=GRO+J1744-28&submit=SIMBAD+search]) | ||
| + | |||
| + | '''Available data''': NuSTAR ObsID 80202027002 | ||
'''Monitoring data''': | '''Monitoring data''': | ||
| Line 8: | Line 10: | ||
= 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 (<ref name="Kouveliotou96A"/>) | + | 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 41: | Line 43: | ||
== X-ray Spectrum == | == X-ray Spectrum == | ||
| + | |||
| + | * Spectrum shows typical cut-off powerlaw like expected from accreting X-ray binary | ||
| + | * Broad iron line at 6-7 keV | ||
=== Cyclotron Features === | === Cyclotron Features === | ||
| + | |||
| + | Cyclotron line in this source is under debate | ||
* 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"/>) | * 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"/>) | ||
* 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"/>) | * 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"/>) | ||
* 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"/>) | * 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"/>) | ||
| − | * | + | * No cyclotron line in low-flux 2017 February outburst (König et al. in prep.) |
'''References''' | '''References''' | ||
Revision as of 14:33, 26 September 2019
Other names : 2EG J1746-2852 ([1])
Available data: NuSTAR ObsID 80202027002
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
- Spectrum shows typical cut-off powerlaw like expected from accreting X-ray binary
- Broad iron line at 6-7 keV
Cyclotron Features
Cyclotron line in this source is under debate
- 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])
- No cyclotron line in low-flux 2017 February outburst (König et al. in prep.)
References
- ↑ Kouveliotou et al., 1996, Nature, Volume 379, Issue 6568, pp. 799-801 (1996) (NASA ADS)
- ↑ Augusteijn, T. & Greiner, J., et al., 1997, ApJ 486, 1013 (NASA ADS)
- ↑ Nishiuchi, M. et al., 2018, ApJ, Vol. 517, Issue 1, pp. 436-448. (NASA ADS)
- ↑ 4.0 4.1 MNRAS, Vol. 380, Issue 4, pp. 1511-1520. (NASA ADS)
- ↑ Masetti et al., ATel, No.5999, March 2014 (NASA ADS)
- ↑ Pintore, F. et al., ATEL, No.5901, Feb 2014 (ATEL)
- ↑ 7.0 7.1 Finger, M. H. et al., Nature, Volume 381, Issue 6580, pp. 291-293 (1996) (NASA ADS)
- ↑ 8.0 8.1 8.2 8.3 D'Ai, A. et al., MNRAS, Volume 449, Issue 4, p.4288-4303 (NASA ADS)
- ↑ Woods, P. M. et al., ApJ, Vol. 517, Issue 1, pp. 431-435 (NASA ADS)
- ↑ 10.0 10.1 Doroshenko et al., 2015, Monthly Notices of the Royal Astronomical Society, Volume 452, Issue 3, p.2490-2499 (NASA ADS)
- ↑ Younes, G. et al, ApJ, Vol. 804, Issue 1, article id. 43, 16 pp. (2015) (NASA ADS)
- ↑ Iaria et al., 2015, A&A, Volume 577, id.A63, 14 pp. (NASA ADS)
- ↑ Maitra et al., 2018, Monthly Notices of the Royal Astronomical Society: Letters, Volume 480, Issue 1, p.L136-L140 (NASA ADS)