XSTAR output

The Spectral Data File: xout_spect1.fits

This ASCII FITS file contains the spectral information. The first extension lists all the user input parameters for this XSTAR run. The second extension contains the spectra with lines binned into the continuum. The columns are the channel energy in \(\text{eV}\), incident, transmitted, and emitted radiation in inward and outward direction, respectively, all specific luminosities in units of \(10^{38}\,\text{erg}\,\text{s}^{-1}\,\text{erg}^{-1}\). The file format is shown below.

No. Type     EXTNAME      BITPIX Dimensions(columns)      PCOUNT  GCOUNT

 0  PRIMARY                 16     0                           0    1
 1  BINTABLE PARAMETERS      8     66(5) 55                    0    1

    Column Name                Format     Dims       Units     TLMIN  TLMAX
    1 index                      1I
    2 parameter                  20A
    3 value                      1E
    4 type                       10A
    5 comment                    30A

 2  TABLE    XSTAR_SPECTRA   8     69(5) 9999                  0    1

    Column Name                Format     Dims       Units     TLMIN  TLMAX
    1 energy                     E13.5               eV
    2 incident                   E13.5               erg/s/erg
    3 transmitted                E13.5               erg/s/erg
    4 emit_inward                E13.5               erg/s/erg
    5 emit_outward               E13.5               erg/s/erg

The Continuum File: xout_cont1.fits

This ASCII FITS file contains the continuum luminosities. The first extension lists all the user input parameters for this XSTAR run. The second extension contains the spectra without lines binned into the continuum. The columns are the channel energy in \(\text{eV}\), incident, transmitted, and emitted specific luminosities in the inward and outward directions, respectively, all in units of \(10^{38}\,\text{erg}\,\text{s}^{-1}\,\text{erg}^{-1}\). The file format is the same as for xout_spect1.fits.

No. Type     EXTNAME      BITPIX Dimensions(columns)      PCOUNT  GCOUNT

 0  PRIMARY                 16     0                           0    1
 1  BINTABLE PARAMETERS      8     66(5) 55                    0    1

    Column Name                Format     Dims       Units     TLMIN  TLMAX
    1 index                      1I
    2 parameter                  20A
    3 value                      1E
    4 type                       10A
    5 comment                    30A

 2  TABLE    XSTAR_SPECTRA   8     69(5) 9999                  0    1

    Column Name                Format     Dims       Units     TLMIN  TLMAX
    1 energy                     E13.5               eV
    2 incident                   E13.5               erg/s/erg
    3 transmitted                E13.5               erg/s/erg
    4 emit_inward                E13.5               erg/s/erg
    5 emit_outward               E13.5               erg/s/erg

The Line Lumnosity File: xout_lines1.fits

This ASCII FITS file contains information about the strongest emission lines. The first extension lists all the user input parameters for this XSTAR run. The second extension lists the 600 strongest emission lines. For each line, the line index (internal reference of XSTAR and the atomic database), the ion (string), the lower and upper level (string), the wavelength (\(\AA\)), the emitted luminosity in forward and backward directions (in units of \(10^{38}\,\text{erg}\,\text{s}^{-1}\)), and optical depth in the forward and backward directions. The file format is shown below.

No. Type     EXTNAME      BITPIX Dimensions(columns)      PCOUNT  GCOUNT

 0  PRIMARY                 16     0                           0    1
 1  BINTABLE PARAMETERS      8     66(5) 55                    0    1

    Column Name                Format     Dims       Units     TLMIN  TLMAX
    1 index                      1I
    2 parameter                  20A
    3 value                      1E
    4 type                       10A
    5 comment                    30A

 2  TABLE    XSTAR_LINES     8     128(9) 600                  0    1

    Column Name                Format     Dims       Units     TLMIN  TLMAX
    1 index                      I6
    2 ion                        A9
    3 lower_level                A20
    4 upper_level                A20
    5 wavelength                 E13.5               A
    6 emit_inward                E13.5               erg/s/10**38
    7 emit_outward               E13.5               erg/s/10**38
    8 depth_inward               E13.5
    9 depth_outward              E13.5

The Abundances Data File: xout_abund1.fits

This ASCII FITS file contains ion abundances as well as heating and cooling rates. Only ions with fractional abundance (relative to its parent element) greater than \(10^{-10}\) (relative to its parent element) are recorded. The elements are ordered by increasing nuclear charge, ions by increasing free charge.

The FITS file has four extensions: spatial ionic abundances, total ionic columns and heating and cooling rates:

No. Type     EXTNAME      BITPIX Dimensions(columns)      PCOUNT  GCOUNT

 0  PRIMARY                 16     0                           0    1
 1  TABLE    ABUNDANCES      8     6621(473) *********         0    1
 2  TABLE    COLUMNS         8     6621(473) *********         0    1
 3  TABLE    HEATING         8     559(40) **********          0    1
 4  TABLE    COOLING         8     573(41) **********          0    1

The “ABUNDANCES” extension contains information about ionic abundance for each spatial zone. Each row contains the radius and size of the spatial zone, the local ionization parameter, electron fraction, density, pressure, temperature, fractional heating-cooling, followed by the abundance for each ion relative to its parent element:

No. Type     EXTNAME      BITPIX Dimensions(columns)      PCOUNT  GCOUNT

 1  TABLE    ABUNDANCES      8     6621(473) *********         0    1

    Column Name                Format     Dims       Units     TLMIN  TLMAX
    1 radius                     E13.5               cm
    2 delta_r                    E13.5               cm
    3 ion_parameter              E13.5               erg*cm/s
    4 x_e                        E13.5
    5 n_p                        E13.5
    6 pressure                   E13.5               dynes/cm**2
    7 temperature                E13.5               10**4 K
    8 frac_heat_error            E13.5
    9 h_i                        E13.5
   10 he_i                       E13.5
   11 he_ii                      E13.5
   12 li_i                       E13.5
   13 li_ii                      E13.5
   14 li_iii                     E13.5
   15 be_i                       E13.5
   16 be_ii                      E13.5
   17 be_iii                     E13.5
   18 be_iv                      E13.5
   [...]

The “COLUMNS” extension has a very similar format but contain column density for each ion in units of \(\text{cm}^{-2}\). In principle, these are integrated abundances from the previous extension, weighted by the elemental abundance and scaled by the total column density. Note that the ion fraction of the fully stripped ion is never tabulated, for any element. The abundance of these ions may be derived from the other ions by calculating one minus the sum of the tabulated ion fractions.

The last two extensions, “HEATING” and “COOLING”, list the Compton and total heating rates, and bremsstrahlung, Compton, and total cooling rates (in \(\text{erg}\,\text{cm}^{-3}\,\text{s}^{-1}\)).

The RRC File: xout_rrc1.fits

This ASCII FITS file contains information contains about the RRCs (radiative bound-free transitions). The first extension lists all the user input parameters for this XSTAR run. The second extension contains for each RRC, the RRC index (internal reference of XSTAR and the atomic database), the ion (string), the bound level (string), the energy (\(\text{eV}\)), the emitted luminosity in forward and backward directions (in units of \(10^{38}\,\text{erg}\,\text{s}^{-1}\)), and optical depth in the forward and backward directions.

No. Type     EXTNAME      BITPIX Dimensions(columns)      PCOUNT  GCOUNT

 0  PRIMARY                 16     0                           0    1
 1  BINTABLE PARAMETERS      8     66(5) 55                    0    1

    Column Name                Format     Dims       Units     TLMIN  TLMAX
    1 index                      1I
    2 parameter                  20A
    3 value                      1E
    4 type                       10A
    5 comment                    30A

 2  TABLE    XSTAR_SPECTRA   8     107(8) 6945                 0    1

    Column Name                Format     Dims       Units     TLMIN  TLMAX
    1 index                      I6
    2 ion                        A9
    3 level                      A20
    4 energy                     E13.5               eV
    5 emit_outward               E13.5               erg/s
    6 emit_inward                E13.5               erg/s
    7 depth_outward              E13.5
    8 depth_inward               E13.5

Detailed Ionic Information: xoNN_detail.fits

This file is only produced for lwrite=1 !

This ASCII FITS file contains all level populations for all spatial zones. This file is large and time-consuming to view and manipulate. For this file, the NN in the name is replaced by the pass number, a 2 digit integer. The first extension lists all the user input parameters for this XSTAR run. Each of the following extension represents a spatial zone, so the number of extensions will depend on the details of the XSTAR calculation. The spatial extension list the index (internal to the XSTAR database), the ion index (internal to the XSTAR database), the excitation energy in \(eV\), the ion string, its atomic number, the configuration string, the ion population relative to the parent ion, the LTE population and the and the level index (relative to the ion). Other useful quantities like the radius, size, temperature, local ionization parameter etc. for each spatial zone are given in the header of each extension.

No. Type     EXTNAME      BITPIX Dimensions(columns)      PCOUNT  GCOUNT

 0  PRIMARY                 16     0                           0    1
 1  BINTABLE PARAMETERS      8     66(5) 55                    0    1

    Column Name                Format     Dims       Units     TLMIN  TLMAX
    1 index                      1I
    2 parameter                  20A
    3 value                      1E
    4 type                       10A
    5 comment                    30A

 2  BINTABLE XSTAR_RADIAL    8     50(9) 2590                  0    1

    Column Name                Format     Dims       Units     TLMIN  TLMAX
    1 index                      1J
    2 ion_index                  1I
    3 e_excitation               1E                  eV
    4 ion                        8A
    5 atomic_number              1I
    6 ion_level                  20A
    7 population                 1E
    8 lte                        1E
    9 upper index                1I

 3  BINTABLE XSTAR_RADIAL    8     50(9) 2590                  0    1

    Column Name                Format     Dims       Units     TLMIN  TLMAX
    1 index                      1J
    2 ion_index                  1I
    3 e_excitation               1E                  eV
    4 ion                        8A
    5 atomic_number              1I
    6 ion_level                  20A
    7 population                 1E
    8 lte                        1E
    9 upper index                1I

 [...]

Detailed Line Information: xoNN_detal2.fits

This file is only produced for lwrite=1 !

This ASCII FITS file contains line emissivities for all spatial zones. This file is large and time-consuming to view and manipulate. For this file, the NN in the name is replaced by the pass number, a 2 digit integer. The first extension lists all the user input parameters for this XSTAR run. Each of the following extension represents a spatial zone, so the number of extensions will depend on the details of the XSTAR calculation. The spatial extension list the line index (internal to the XSTAR database), the wavelength (in \(\AA\)), the ion string, the lower and upper level configuration strings, the inward and outward emission, the line opacity, and inward and outward optical depth. Other useful quantities like the radius, size, temperature, local ionization parameter etc. for each spatial zone are given in the header of each extension.

No. Type     EXTNAME      BITPIX Dimensions(columns)      PCOUNT  GCOUNT

 0  PRIMARY                 16     0                           0    1
 1  BINTABLE PARAMETERS      8     66(5) 55                    0    1

    Column Name                Format     Dims       Units     TLMIN  TLMAX
    1 index                      1I
    2 parameter                  20A
    3 value                      1E
    4 type                       10A
    5 comment                    30A

 2  BINTABLE XSTAR_RADIAL    8     76(10) 18662                0    1

    Column Name                Format     Dims       Units     TLMIN  TLMAX
    1 index                      1J
    2 wavelength                 1E                  A
    3 ion                        8A
    4 lower_level                20A
    5 upper_level                20A
    6 emis_inward                1E                  erg/cm^3/s
    7 emis_outward               1E                  erg/cm^3/s
    8 opacity                    1E                  /cm
    9 tau_in                     1E
   10 tau_out                    1E

 3  BINTABLE XSTAR_RADIAL    8     76(10) 18662                0    1

    Column Name                Format     Dims       Units     TLMIN  TLMAX
    1 index                      1J
    2 wavelength                 1E                  A
    3 ion                        8A
    4 lower_level                20A
    5 upper_level                20A
    6 emis_inward                1E                  erg/cm^3/s
    7 emis_outward               1E                  erg/cm^3/s
    8 opacity                    1E                  /cm
    9 tau_in                     1E
   10 tau_out                    1E

[...]

Detailed RRC Information: xoNN_detal3.fits

This file is only produced for lwrite=1 !

This ASCII FITS file contains all RRC emissivities and opacities for all spatial zones. This file is large and time-consuming to view and manipulate. For this file, the NN in the name is replaced by the pass number, a 2 digit integer. The first extension lists all the user input parameters for this XSTAR run. Each of the following extension represents a spatial zone, so the number of extensions will depend on the details of the XSTAR calculation. The spatial extension list the RRC and level indices (internal to the XSTAR database), the energy (in \(eV\)), the ion string, the lower and upper level configuration strings (upper is continuum), the inward and outward emission, the integrated absorption, the RRC opacity, and inward and outward optical depth. Other useful quantities like the radius, size, temperature, local ionization parameter etc. for each spatial zone are given in the header of each extension.

No. Type     EXTNAME      BITPIX Dimensions(columns)      PCOUNT  GCOUNT

 0  PRIMARY                 16     0                           0    1
 1  BINTABLE PARAMETERS      8     66(5) 55                    0    1

    Column Name                Format     Dims       Units     TLMIN  TLMAX
    1 index                      1I
    2 parameter                  20A
    3 value                      1E
    4 type                       10A
    5 comment                    30A

 2  BINTABLE XSTAR_RADIAL    8     84(12) 2502                 0    1

    Column Name                Format     Dims       Units     TLMIN  TLMAX
    1 rrc index                  1J
    2 level index                1J
    3 energy                     1E                  ev
    4 ion                        8A
    5 lower_level                20A
    6 upper_level                20A
    7 emis_inward                1E                  erg/cm^3/s
    8 emis_outward               1E                  erg/cm^3/s
    9 integrated absn            1E                  erg/cm^3/s
   10 opacity                    1E                  /cm
   11 tau_in                     1E
   12 tau_out                    1E

[...]

Detailed Line Information: xoNN_detal4.fits

This file is only produced for lwrite=1 !

This ASCII FITS file contains binned continuum specific luminosities and emissivities. This file is large and time-consuming to view and manipulate. For this file, the NN in the name is replaced by the pass number, a 2 digit integer. The first extension lists all the user input parameters for this XSTAR run. Each of the following extension represents a spatial zone, so the number of extensions will depend on the details of the XSTAR calculation. Note that specific luminosity has units \(10^{38}\,\text{erg}\,\text{s}^{-1}\,\text{erg}^{-1}\). The values in the columns in the spatial extensions are as follows:

The first two columns are the index and energy (in \(\text{eV}\)) of each spectral channel. The next for columns are

  • \(\texttt{zrems(1)}\): the specific luminosity used internally by xstar, calculated including all absorption and emission

  • \(\texttt{zrems(2)}\): specific luminosity which includes only emission from the model gas in the inward (reflected) direction (i.e., no incident radiation included)

  • \(\texttt{zrems(3)}\): specific luminosity which includes only emission from the model gas in in the outward (transmitted) direction (i.e., no incident radiation included)

  • \(\texttt{zrems(4)}\): specific luminosity which includes only emission from the model gas in the inward (reflected) direction but not including line emission

  • \(\texttt{zrems(5)}\): specific luminosity which includes only emission from the model gas in in the outward (transmitted) direction but not including line emission.

The remaining columns contain the opacity, the emission in inward and outward directions, and the optical depths in inward and outward directions.

No. Type     EXTNAME      BITPIX Dimensions(columns)      PCOUNT  GCOUNT

 0  PRIMARY                 16     0                           0    1
 1  BINTABLE PARAMETERS      8     66(5) 55                    0    1

    Column Name                Format     Dims       Units     TLMIN  TLMAX
    1 index                      1I
    2 parameter                  20A
    3 value                      1E
    4 type                       10A
    5 comment                    30A

 2  BINTABLE XSTAR_RADIAL    8     48(12) 9999                 0    1

    Column Name                Format     Dims       Units     TLMIN  TLMAX
    1 index                      1J
    2 energy                     1E                  ev
    3 zrems(1)                   1E                  erg/s
    4 zrems(2)                   1E                  erg/s
    5 zrems(3)                   1E                  erg/s
    6 zrems(4)                   1E                  erg/s
    7 zrems(5)                   1E                  erg/s
    8 opacity                    1E                  /cm
    9 emis out                   1E                  erg/cm**3/s
   10 emis in                    1E                  erg/cm**3/s
   11 fwd dpth                   1E
   12 bck dpth                   1E

XSTAR Run Log: xout_step.log

This file is always written but the parameter lprint controls the level of detail!

In any case, this ASCII text file contains the input parameters and a log of the temperature and other useful quantities (radius, \(\Delta R/R\) the fractional distance from the illuminated cloud face, column density, ionization parameter, electron fraction, proton number density, temperature, fractional heating-cooling rates, continuum optical depth at the Lyman continuum in the transmitted and reflected directions, and the number of iterations required to reach thermal equilibrium. This is the same as the information printed to the screen. In addition, at the end of a model calculation the luminosities of the 500 strongest lines and the 500 strongest RRCs are printed, sorted by luminosity, along with the energy budget: total energy absorbed, emitted in the continuum, emitted in lines, and the fractional difference between the first quantity and the sum of the latter two. Models with energy budget errors greater than a few percent should likely be rerun with smaller value of emult.