J/A+A/395/129 Cyclotron lines in Vela X-1 (Kreykenbohm+, 2002)
Confirmation of two cyclotron lines in Vela X-1.
Kreykenbohm I., Corburn W., Wilms J., Kretschmar P., Staubert R.,
Heindl W.A., Rothschild, R.E.
<Astron. Astrophys. 395, 129 (2002)>
=2002A&A...395..129K 2002A&A...395..129K
ADC_Keywords: X-ray sources ; Magnetic fields
Keywords: X-rays: stars - stars: magnetic fields -
stars: pulsars: individual: Vela X-1
Description:
Fitting parameters for the phase resolved spectra of the 2000 and 1998
observation are given. The model in use is the Negative Positive
EXponential (NPEX) model (with Gamma2 always fixed to -2, Mihara,
1995, Ph.D. Thesis, Riken, Tokyo) modified by photoelectric
absorption, an additive iron line at ∼6.4keV, and none, one, or two
cyclotron resonant scattering features (CRSF)s at ∼25 and ∼50keV.
The phase bins for the 2000 observation are:
- rise, center, and fall of the main pulse
- rise part 1, rise part 2, center, and fall of the secondary pulse
- the two inter pulse phases
The phase bins for the 1998 observation are:
- rise and fall of the main pulse
- rise and fall of the secondary pulse
- the two inter pulse phases
Objects:
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RA (2000) DE Designation(s)
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09 02 06.9 -40 33 17 Vela X-1 = HD 77581
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3a.dat 88 14 2000 observation, Rise of the main Pulse
table3b.dat 88 14 2000 observation, Center of the main Pulse
table3c.dat 88 14 2000 observation, Fall of the main Pulse
table3d.dat 88 14 2000 observation, Intermediate Pulse I
table3e.dat 88 14 2000 observation, Rise part I of the secondary Pulse
table3f.dat 88 14 2000 observation, Rise part II of the secondary Pulse
table3g.dat 88 14 2000 observation, Center of the secondary Pulse
table3h.dat 88 14 2000 observation, Fall of the secondary Pulse
table3i.dat 88 14 2000 observation, Intermediate Pulse II
table3j.dat 88 14 1998 observation, Rise of the main Pulse
table3k.dat 88 14 1998 observation, Fall of the main Pulse
table3l.dat 88 14 1998 observation, Intermediate Pulse I
table3m.dat 88 14 1998 observation, Rise of the secondary Pulse
table3n.dat 88 14 1998 observation, Fall of the secondary Pulse
table3o.dat 89 14 1998 observation, Intermediate Pulse II
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Byte-by-byte Description of file: table*.dat
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Bytes Format Units Label Explanations
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1 A1 --- tno [a-o] Table number from a to o
3- 17 A15 --- Param Name of the fit parameter (1)
19- 24 F6.2 --- Cycleo ? Fit value for a fit of the fundamental (w/o)
cyclotron resonant scattering feature (CRSF)
28- 31 F4.2 --- E_Cycleo ? Error in Cycleo (upper limit)
36- 39 F4.2 --- e_Cycleo ? Error in Cycleo (lower limit)
42- 47 F6.2 --- Cycle1 ? Fit value for a fit of the first harmonic CRSF
52- 56 F5.2 --- E_Cycle1 ? Error in Cycle1 (upper limit)
60- 64 F5.2 --- e_Cycle1 ? Error in Cycle1 (lower limit)
67- 71 F5.2 --- Cycle2 ? Fit value for a fit of the second harmonic CRSF
75- 80 F6.2 --- E_Cycle2 ? Error in Cycle2 (upper limit)
81 A1 --- nECycle2 [i] i: upper limit of Cycle2 is +infinity
85- 88 F4.2 --- e_Cycle2 ? Error in Cycle2 (lower limit)
89 A1 --- neCycle2 [i] i: lower limit of Cycle2 is -infinity
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Note (1): Fit parameters:
NH: Hydrogen column density, in 1022cm-2
Fe: Energy of the iron line, in keV
Fe-Sigma: Width of the Gaussian iron line, in keV
Gamma_1: Nebula power law photon index
Gamma_2: Pulsar power law photon index
Efold: Folding energy of the high energy exponential cutoff
E_C,1: Energy of the first harmonic CRSF, in keV
Sigma_C,1: Width of the first harmonic CRSF, in keV
Tau_C,1: Optical depth of the first harmonic CRSF, in keV
E_C,2: Energy of the second harmonic CRSF, in keV
Sigma_C,2: Width of the second harmonic CRSF, in keV
Tau_C,2: Optical depth of the second harmonic CRSF, in keV
Chi2: Residual of fit
DOF: Degrees of freedom of the fit
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Acknowledgements: Ingo Kreykenbohm
(End) Patricia Bauer [CDS] 04-Nov-2002