Cepheus X-4
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Also known as: GS 2138 + 56, V* V490 Cep
Simbad
Monitoring Data: CGRO/BATSE [Swift]MAXI Fermi/GBM pulsed flux RXTE/ASM
Coordinates
| Ra | 21h 39m 30.6s | Dec | +56º 59' 12.9 |
| l | 99.01 | b | +3.31 |
([1])
Binary System
Known to be a Be high mass X-ray binary system.
Distance
Determined to be 3.8 ± 0.6 kpc ([2])
Orbit
Period: Between 20-23 days[3][4]
Companion
Spectral Type: B1 V-B2 V
Magnitude: mv = 14.2, Mv = -(2.5-3.8)
([2])
Available Data
- RXTE: Mostly individual observations in 1997, 2002 and 2004 for ≤3 ksec. Up to 50 ksec in 1997 and 2002.
- RXTE: As part of the All-Sky Monitor Long Term Observed Sources. First observed in 1996.
- Ginga: Various observations in April 1988.
- INTEGRAL: Many pointed observations as part of CORE and GPS.
- Suzaku: None as of yet.
Flux
Luminosity:
- Quiescent: Lx(0.1-100keV) = (3.3-6.2) 1033 erg.s-1 ([2])
- Outburst: Fermi/GBM detected the 2009 outburst where Lx(12-25 keV) = 4.8380 1035 erg.s-1 was measured. ([5])
Cyclotron Resonance: Detected at 30.7 keV. ([6]) ([4]). Asymmetric shape and luminosity dependence found by [7].
Spectrum:
Figure taken from [4]
Pulse Profile
Period: 66.30 s ([4])
Pulse profiles in the 2-5keV for various observations. Luminosity decreases from top to bottom.
References
- ↑ Cite error: Invalid
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<ref>tag; no text was provided for refs namedBonnetBidaudMouchet98 - ↑ Cite error: Invalid
<ref>tag; no text was provided for refs namedKoyamaK91 - ↑ 4.0 4.1 4.2 4.3 Cite error: Invalid
<ref>tag; no text was provided for refs namedMcBride07 - ↑ Cite error: Invalid
<ref>tag; no text was provided for refs namedBeklen09 - ↑ Cite error: Invalid
<ref>tag; no text was provided for refs namedMihara91 - ↑ Cite error: Invalid
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