J/ApJ/376/161 X-ray spectra of bursting neutron stars (Madej+, 1991) ================================================================================ Model atmospheres and X-ray spectra of bursting neutron stars. Madej J. =1991ApJ...376..161M ================================================================================ ADC_Keywords: Models, atmosphere ; Binaries, X-ray Keywords: radiative transfer - stars: atmospheres - stars: neutron - X-rays: bursts Abstract: X-ray burst sources represent a class of accreting neutron stars in close binary systems which do not exhibit any traces of the magnetic field. We present new method of hot model atmosphere computations with account of Compton scattering on free electrons and computed set of plane-parallel hydrogen-helium atmospheres and X-ray spectra of bursting neutron stars. Models were computed with precise angle-dependent radiative transfer under constrains of radiative and hydrostatic equilibrium. Compton scattering opacity included both the Klein-Nishina corrections and the effects of relativistic Maxwellian thermal motion of scattering electrons. Compton redistribution function allows for large energy exchange between X-ray photons and scattering electrons. Description: Grid consists of 20 continuum X-ray spectra of hot model atmospheres computed for the single hydrogen-helium chemical composition with the helium number abundance He/H=0.11 (solar value). Model atmospheres and spectra were computed for effective temperatures T_eff_=8x10^6^, 1.257x10^7^, 2x10^7^ and 3x10^7^K and various surface gravities logg=12.5 to 15.0 (g in units cm/s^2^). File 'table1.dat' presents values of model parameters and corresponding spectral hardening factors, T_col/T_eff. Also critical gravity g_cr was estimated for each value of T_eff. Values of effective temperatures T_eff_, gravities logg and fluxes are measured on the neutron star surface. File Summary: -------------------------------------------------------------------------------- FileName Lrecl Records Explanations -------------------------------------------------------------------------------- ReadMe 80 . This file table1.dat 84 4 *Model parameters and f_c_=T_col_/T_eff_ ratios (spectral hardening factor) table2.dat 59 200 Photon energy and fluxes -------------------------------------------------------------------------------- Note on table1.dat: Parameters of neutron star model atmospheres and spectra. -------------------------------------------------------------------------------- See also: J/AcA/41/73 : Model atmospheres of X-ray bursting neutron stars (Madej, 1991) Byte-by-byte Description of file: table1.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1 I1 --- nr [1/4] Index of effective temperature 3- 11 E9.3 K Teff Corresponding effective temperature (8.00E+06, 1.257E+07, 2.00E+07, 3.00E+07) 13- 18 F6.3 [cm/s2] loggcr [12.39/14.65] Logarithm of critical gravity 20- 24 F5.2 [cm/s2] logg1 [15] Logarithm of surface gravity 1 26- 29 F4.2 --- fc1 [1.36/1.41] Spectral hardening factor for logg1 31- 35 F5.2 [cm/s2] logg2 [14.5/14.8] Logarithm of surface gravity 2 37- 40 F4.2 --- fc2 [1.36/1.48] Spectral hardening factor for logg2 42- 46 F5.2 [cm/s2] logg3 [14.0/14.7] Logarithm of surface gravity 3 48- 51 F4.2 --- fc3 [1.36/1.55] Spectral hardening factor for logg3 53- 57 F5.2 [cm/s2] logg4 [13.5/14.1]? Logarithm of surface gravity 4 59- 62 F4.2 --- fc4 [1.45/1.52]? Spectral hardening factor for logg4 64- 68 F5.2 [cm/s2] logg5 [13.0/14.0]? Logarithm of surface gravity 5 70- 73 F4.2 --- fc5 [1.52/1.58]? Spectral hardening factor for logg5 75- 79 F5.2 [cm/s2] logg6 [12.5/13.2]? Logarithm of surface gravity 6 81- 84 F4.2 --- fc6 [1.62/1.62]? Spectral hardening factor for logg6 -------------------------------------------------------------------------------- Byte-by-byte Description of file: table2.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1 I1 --- nr [1/4] Index of effective temperature 5- 11 F7.4 keV E [0.058/62.211] Photon energy 14- 19 F6.3 [mW/m2/keV] FE1 ? Log flux F_E_ for logg1 22- 27 F6.3 [mW/m2/keV] FE2 ? Log flux F_E_ for logg2 30- 35 F6.3 [mW/m2/keV] FE3 ? Log flux F_E_ for logg3 38- 43 F6.3 [mW/m2/keV] FE4 ? Log flux F_E_ for logg4 46- 51 F6.3 [mW/m2/keV] FE5 ? Log flux F_E_ for logg5 54- 59 F6.3 [mW/m2/keV] FE6 ? Log flux F_E_ for logg6 -------------------------------------------------------------------------------- Acknowledgements: Jerzy Madej, jm(at)astrouw.edu.pl, University of Warsaw ================================================================================ (End) Jerzy Madej [Warsaw], Patricia Vannier [CDS] 28-Nov-2014