J/A+A/386/1001 Thermal emission from low-field neutron stars (Gaensicke+, 2002)
Thermal emission from low-field neutron stars
Gaensicke, B.T., Braje, T.M., Romani, R.W.
<Astron. Astrophys. 386, 1001 (2002)>
=2002A&A...386.1001G 2002A&A...386.1001G
ADC_Keywords: Models, atmosphere
Keywords: stars: neutron ; stars: atmospheres - radiative transfer -
radiation mechanisms: thermal
Description:
We present a new grid of LTE model atmospheres for weakly magnetic
(B≲1010G) neutron stars, using X opacity and equation of state data
from the OPAL project and employing a fully frequency- and
angle-dependent radiation transfer.
Model spectra for low-field neutron stars with three different
photospheric compositions are presented: (1) pure hydrogen
atmospheres, (2) atmospheres with solar abundances, and (3) pure iron
atmospheres. Each grid covers 29 effective temperatures
log(Teff[K])=5.10-6.50 in steps of 0.05. The model spectra are
tabulated as angle-averaged unredshifted (surface) Eddington fluxes.
All spectra have been calculated for a canonical neutron star
configuration, Mns=1.4M☉, Rns=10km, corresponding to a
surface gravitational acceleration of log(g)=14.386.
The same model grids are also available as XSPEC tables at
http://legacy.gsfc.nasa.gov/docs/xanadu/xspec/models/gbr.html
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
h.dat 359 10000 Neutron star model spectra, pure hydrogen atmosphere
fe.dat 359 10000 Neutron star model spectra, pure iron atmosphere
sol.dat 359 10000 Neutron star model spectra, solar abundances atmosphere
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See also:
http://legacy.gsfc.nasa.gov/docs/xanadu/xspec/models/gbr.html :
Neutron stars atmosphere models
Byte-by-byte Description of file: h.dat fe.dat sol.dat
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Bytes Format Units Label Explanations
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1- 11 E11.5 keV E Energy level
13- 23 E11.5 mW/m2/keV He5.10 Eddington flux for log(Teff)=5.10 (1)
25- 35 E11.5 mW/m2/keV He5.15 Eddington flux for log(Teff)=5.15 (1)
37- 47 E11.5 mW/m2/keV He5.20 Eddington flux for log(Teff)=5.20 (1)
49- 59 E11.5 mW/m2/keV He5.25 Eddington flux for log(Teff)=5.25 (1)
61- 71 E11.5 mW/m2/keV He5.30 Eddington flux for log(Teff)=5.30 (1)
73- 83 E11.5 mW/m2/keV He5.35 Eddington flux for log(Teff)=5.35 (1)
85- 95 E11.5 mW/m2/keV He5.40 Eddington flux for log(Teff)=5.40 (1)
97-107 E11.5 mW/m2/keV He5.45 Eddington flux for log(Teff)=5.45 (1)
109-119 E11.5 mW/m2/keV He5.50 Eddington flux for log(Teff)=5.50 (1)
121-131 E11.5 mW/m2/keV He5.55 Eddington flux for log(Teff)=5.55 (1)
133-143 E11.5 mW/m2/keV He5.60 Eddington flux for log(Teff)=5.60 (1)
145-155 E11.5 mW/m2/keV He5.65 Eddington flux for log(Teff)=5.65 (1)
157-167 E11.5 mW/m2/keV He5.70 Eddington flux for log(Teff)=5.70 (1)
169-179 E11.5 mW/m2/keV He5.75 Eddington flux for log(Teff)=5.75 (1)
181-191 E11.5 mW/m2/keV He5.80 Eddington flux for log(Teff)=5.80 (1)
193-203 E11.5 mW/m2/keV He5.85 Eddington flux for log(Teff)=5.85 (1)
205-215 E11.5 mW/m2/keV He5.90 Eddington flux for log(Teff)=5.90 (1)
217-227 E11.5 mW/m2/keV He5.95 Eddington flux for log(Teff)=5.95 (1)
229-239 E11.5 mW/m2/keV He6.00 Eddington flux for log(Teff)=6.00 (1)
241-251 E11.5 mW/m2/keV He6.05 Eddington flux for log(Teff)=6.05 (1)
253-263 E11.5 mW/m2/keV He6.10 Eddington flux for log(Teff)=6.10 (1)
265-275 E11.5 mW/m2/keV He6.15 Eddington flux for log(Teff)=6.15 (1)
277-287 E11.5 mW/m2/keV He6.20 Eddington flux for log(Teff)=6.20 (1)
289-299 E11.5 mW/m2/keV He6.25 Eddington flux for log(Teff)=6.25 (1)
301-311 E11.5 mW/m2/keV He6.30 Eddington flux for log(Teff)=6.30 (1)
313-323 E11.5 mW/m2/keV He6.35 Eddington flux for log(Teff)=6.35 (1)
325-335 E11.5 mW/m2/keV He6.40 Eddington flux for log(Teff)=6.40 (1)
337-347 E11.5 mW/m2/keV He6.45 Eddington flux for log(Teff)=6.45 (1)
349-359 E11.5 mW/m2/keV He6.50 Eddington flux for log(Teff)=6.50 (1)
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Note (1): Eddington flux and radiation flux are related by
4*π*H(E)=F(E), i.e.
4*π*Integral{0.to.infinity}(H(E)dE)=σ*Teff4
where σ is the Stefan-Boltzmann constant (5.67x10-8 SI)
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Acknowledgements: Boris Gaensicke
(End) Patricia Bauer [CDS] 24-Apr-2002