ChiantiPy.tools package

Submodules

ChiantiPy.tools.archival module

Functions for reading pre-v8 CHIANTI files

ChiantiPy.tools.archival.elvlcRead(ions, filename=0, verbose=0, useTh=0)

read a chianti energy level file and returns {“lvl”:lvl,”conf”:conf,”term”:term,”spin”:spin,”l”:l,”spd”:spd,”j”:j ,”mult”:mult,”ecm”:ecm,”eryd”:eryd,”ecmth”:ecmth,”erydth”:erydth,”ref”:ref,”pretty”:pretty, ‘ionS’:ions} if a energy value for ecm or eryd is zero(=unknown), the theoretical values (ecmth and erydth) are inserted

ChiantiPy.tools.archival.elvlcWrite(info, outfile=None, addLvl=0)

Write Chianti data to .elvlc file.

Parameters:
  • info (dict) – Information about the Chianti data to write. Should contain the following keys: ionS, the Chianti style name of the ion such as c_4 conf, an integer denoting the configuration - not too essential term, a string showing the configuration spin, an integer of the spin of the state in LS coupling l, an integer of the angular momentum quantum number spd, an string for the alphabetic symbol of the angular momemtum, S, P, D, etc j, a floating point number, the total angular momentum ecm, the observed energy in inverse cm, if unknown, the value is 0. eryd, the observed energy in Rydbergs, if unknown, the value is 0. ecmth, the calculated energy from the scattering calculation, in inverse cm erydth, the calculated energy from the scattering calculation in Rydbergs ref, the references in the literature to the data in the input info
  • outfile (str) – Output filename. ionS+’.elvlc’ (in current directory) if None
  • addLvl (int) – Add a constant value to the index of all levels

Notes

For use with files created before elvlc format change in November 2012

See also

ChiantiPy.tools.io.elvlcWrite()
Write .elvlc file using the new format.
ChiantiPy.tools.archival.wgfaRead(ions, filename=None, elvlcname=-1, total=False, verbose=False)

Read CHIANTI data from a .wgfa file.

Parameters:
  • ions (str) – Ion, e.g. ‘c_5’ for C V
  • filename (str) – Custom filename, will override that specified by ions
  • elvlcname (str) – If specified, the lsj term labels are returned in the pretty1 and pretty2 keys of Wgfa
  • total (bool) – Return the level 2 avalue data in Wgfa
  • verbose (bool)
Returns:

Wgfa – Information read from the .wgfa file. The dictionary structure is {“lvl1”,”lvl2”,”wvl”,”gf”,”avalue”,”ref”,”ionS”,”filename”}

Return type:

dict

Notes

This is text-wise not different than the v8 version except that it uses the archival elvlcRead in ~ChiantiPy.tools.archival though this has now been commented out. Can this routine be removed? Should the elvlcRead routine be uncommented?

See also

ChiantiPy.tools.io.wgfaRead()
Read .wgfa file with the new format.

ChiantiPy.tools.constants module

A set of physical constants, in (mostly) cgs unit system. Most are from [11].

References

[11]NIST Reference on Constants, Units and Uncertainty (link)

Notes

Many of these can be replaced by the ~astropy.constants module. Elemental symbols can be removed in favor of the periodictable module. Spectroscopic roman numerals can be removed in favor of roman module. The Gauss-Laguerre weights can be calculated by ~numpy.polynomial.laguerre.laggauss.

ChiantiPy.tools.data module

Module for collecting various top-level Chianti data

Descriptions for keywordArgs:

  • temperature : temperature (in K)
  • eDensity : electron density (in \(\mathrm{cm}^{-3}\))
  • hDensity : hydrogen density (in \(\mathrm{cm}^{-3}\))
  • pDensity : proton density (in \(\mathrm{cm}^{-3}\))
  • radTemperature : radiation temperature of central source (in K)
  • rStar : distance of the plasma from the source (in units of the source’s radius)
  • distance : distance from the central source
Parameters:
  • XUVTOP (str) – the root of the CHIANTI database
  • Defaults (dict) – default values used by ChiantiPy, can also be set by an optional HOME/.chianti/chiantirc file
  • Ip (np.ndarray) – the ionization potentials for all ionization stages up to Zn, in eV
  • MasterList (list) – the CHIANTI style names of all ions in the CHIANTI database
  • IoneqAll (dict) – a dict containing the ionization equilibrium values for the default ionization file
  • ChiantiVersion (str) – the version of the CHIANTI database
  • AbundanceDefault (dict) – the elemental abundances in the default abundance file
  • AbundanceList (list) – the names of all abundance files included in the CHIANTI database
  • GrndLevels (list) – the number of levels that should be considered in an ionization calculation

ChiantiPy.tools.filters module

Line profile filters for creating synthetic spectra.

ChiantiPy.tools.filters.boxcar(wvl, wvl0, factor=None)

Box-car filter

Parameters:
  • wvl (~numpy.ndarray) – Wavelength array
  • wvl0 (~numpy.float64) – Wavelength filter should be centered on.
  • factor (~numpy.float64) – Full width of the box-car filter
ChiantiPy.tools.filters.gaussian(wvl, wvl0, factor=1.0)

A gaussian filter

Parameters:
  • wvl (~numpy.ndarray) – Wavelength array
  • wvl0 (~numpy.float64) – Wavelength filter should be centered on.
  • factor (~numpy.float64) – Gaussian width
  • integrated value is unity
ChiantiPy.tools.filters.gaussianR(wvl, wvl0, factor=1000.0)

A gaussian filter where the gaussian width is given by wvl0/factor.

Parameters:
  • wvl (~numpy.ndarray) – Wavelength array
  • wvl0 (~numpy.float64) – Wavelength filter should be centered on.
  • factor (~numpy.float64) – Resolving power
ChiantiPy.tools.filters.lorentz(wvl, wvl0, factor=1.0)

Lorentz profile filter with the exception that all factors are in wavelength units rather than frequency as the lorentz profile is usually defined.

Parameters:
  • wvl (~numpy.ndarray) – Wavelength array
  • wvl0 (~numpy.float64) – Wavelength filter should be centered on.
  • factor (~numpy.float64) – Value of the so-called constant gamma
  • integrated value is unity
  • the FWHM is 2*gamma
  • .. math:: – L = frac{1}{pi gamma} frac{ gamma^2}{(lambda - lambda_0)^2 + gamma^2}
ChiantiPy.tools.filters.moffat(wvl, wvl0, factor=2.5)

Moffat profile with parameters suited to Chandra Letg spectra

Parameters:
  • wvl (~numpy.ndarray) – Wavelength array
  • wvl0 (~numpy.float64) – Wavelength the filter is centered on.
  • factor (~numpy.float64) – Resolving power (TODO: correct description)
ChiantiPy.tools.filters.voigt(wvl, wvl0, factor=(0.5, 1.0))

pseudo-Voigt filter the sum of a Gaussian and a Lorentzian

Parameters:
  • wvl (~numpy.ndarray) – Wavelength array
  • wvl0 (~numpy.float64) – Wavelength the filter is centered on.
  • factor (array-type) – contains the following 2 parameters
  • A (~numpy.float64) – relative size of gaussian and lorentz components must be between 0. and 1. but this is not currently checked
  • sigma (~numpy.float64) – the gaussian width of the gaussian profile (the standard deviation) also creates the lorentz component with the same fwhm

ChiantiPy.tools.io module

Reading and writing functions

ChiantiPy.tools.io.abundanceRead(abundancename='')

Read abundance file abundancename and return the abundance values relative to hydrogen

ChiantiPy.tools.io.autoRead(ions, filename=None, total=True, verbose=False)

Read CHIANTI autoionization rates from a .auto file.

Parameters:
  • ions (str) – Ion, e.g. ‘c_5’ for C V
  • filename (str) – Custom filename, will override that specified by ions
  • elvlcname (str) – If specified, the lsj term labels are returned in the ‘pretty1’ and ‘pretty2’ keys of ‘Wgfa’ dict
  • total (bool) – Return the summed level 2 autoionization rates in ‘Auto’
  • verbose (bool)
Returns:

Auto – Information read from the .wgfa file. The dictionary structure is {“lvl1”, “lvl2”, “avalue”, “pretty1”, “pretty2”, “ref”,”ionS”, “filename”}

Return type:

dict

ChiantiPy.tools.io.autoWrite(info, outfile=None, minBranch=None)

Write data to a CHIANTI .wgfa file

Parameters:
  • info (dict) – Should contain the following: ionS, the Chianti style name of the ion such as c_4 for C IV, lvl1, the lower level, the ground level is 1, lvl2, the upper level, wvl, the wavelength (in Angstroms), avalue, the autoionization rate, pretty1, descriptive text of the lower level (optional), pretty2, descriptive text of the upper level (optiona), ref, reference text, a list of strings
  • outfile (str)
  • minBranch (~numpy.float64) – The transition must have a branching ratio greater than the specified to be written to the file
ChiantiPy.tools.io.cireclvlRead(ions, filename=None, filetype='cilvl')

Read Chianti cilvl, reclvl, or rrlvl files and return data

Parameters:
  • ions (str) – Ion, e.g. ‘c_5’ for C V
  • filename (str, optional) – Custom filename, will override that specified by ions
  • filetype (str) – {‘cilvl’, ‘reclvl’, ‘rrlvl’} Type of the file to read
ChiantiPy.tools.io.convertName(name)

Convert ion name string to Z and Ion and other interesting info

Parameters:name (str) – a generic name of an ion in the CHIANTI database, such as fe_14 for Fe XIV

Notes

A duplicate of the routine in ChiantiPy.tools.util but needed by masterList Info TODO: Put in separate module to avoid multiple copies

ChiantiPy.tools.io.defaultsRead(verbose=False)

Read in configuration from .chiantirc file or set defaults if one is not found.

ChiantiPy.tools.io.diRead(ions, filename=None)

Read chianti direct ionization .params files and return data.

Parameters:
  • ions (str) – Ion, e.g. ‘c_5’ for C V
  • filename (str, optional) – Custom filename, will override that specified by ions
ChiantiPy.tools.io.drRead(ions, filename=None)

Read CHIANTI dielectronic recombination .drparams files if filename is set, then reads that file

ChiantiPy.tools.io.eaRead(ions, filename=None)

Read a CHIANTI excitation-autoionization file and calculate the EA ionization rate data derived from splupsRead.

Parameters:
  • ions (str) – Ion, e.g. ‘c_5’ for C V
  • filename (str, optional) – Custom filename, will override that specified by ions
ChiantiPy.tools.io.elvlcRead(ions, filename=None, getExtended=False, verbose=False, useTh=True)

Reads the new format elvlc files.

Parameters:
  • ions (str) – Ion, e.g. ‘c_5’ for C V
  • filename (str, optional) – Custom filename, will override that specified by ions
  • getExtended (bool)
  • verbose (bool)
  • useTh (bool) – If True, the theoretical values (ecmth and erydth) are inserted when an energy value for ecm or eryd is zero(=unknown)
ChiantiPy.tools.io.elvlcWrite(info, outfile=None, round=0, addLvl=0, includeRyd=False, includeEv=False)

Write Chianti data to .elvlc file.

Parameters:
  • info (dict) – Information about the Chianti data to write. Should contain the following keys: ionS, the Chianti style name of the ion such as c_4 term, a string showing the configuration spin, an integer of the spin of the state in LS coupling l, an integer of the angular momentum quantum number spd, an string for the alphabetic symbol of the angular momemtum, S, P, D, etc j, a floating point number, the total angular momentum ecm, the observed energy in inverse cm, if unknown, the value is 0. eryd, the observed energy in Rydbergs, if unknown, the value is 0. ecmth, the calculated energy from the scattering calculation, in inverse cm erydth, the calculated energy from the scattering calculation in Rydbergs ref, the references in the literature to the data in the input info
  • outfile (str) – Output filename. ionS + ‘.elvlc’ (in current directory) if None
  • round (int) – input to ‘np.round’ to round input values to maintain the correct number of significant figures
  • addLvl (int) – Add a constant value to the index of all levels
  • includeRyd (bool) – If True, write the Rydberg energies in the extended area, delimited by a comma
  • includeEv (bool) – If True, write the energies in eV in the extended area, delimited by a comma

Notes

For use with files created after elvlc format change in November 2012

See also

ChiantiPy.tools.archival.elvlcWrite()
Write .elvlc file using the old format.
ChiantiPy.tools.io.fblvlRead(ions, filename=None, verbose=False)

Read a Chianti energy level file for calculating the free-bound continuum

ChiantiPy.tools.io.gffRead()

Read the free-free gaunt factors of [1].

References

[1](1, 2) Sutherland, R. S., 1998, MNRAS, 300, 321

Notes

This function reads the file and reverses the values of g2 and u

ChiantiPy.tools.io.gffintRead()

Read the integrated free-free gaunt factors of [1].

ChiantiPy.tools.io.grndLevelsRead()

to read the grndLevels.dat file give the number of ground levels to sum over in populate and drPopulate

ChiantiPy.tools.io.ioneqRead(ioneqName='', minIoneq=1e-20, verbose=False)

Reads an ioneq file ionization equilibrium values less then minIoneq are returns as zeros :returns: {‘ioneqname’,’ioneqAll’,’ioneqTemperature’,’ioneqRef’} – Ionization equilibrium values and the reference to the literature :rtype: dict

ChiantiPy.tools.io.ipRead(verbose=False)

Reads the ionization potential file

Returns:ip – Ionization potential (in eV)
Return type:array-like
ChiantiPy.tools.io.itohRead()

Read in the free-free gaunt factors of [2].

References

[2]Itoh, N. et al., 2000, ApJS, 128, 125
ChiantiPy.tools.io.klgfbRead()

Read CHIANTI files containing the free-bound gaunt factors for n=1-6 from [13].

Returns:{‘pe’, ‘klgfb’} – Photon energy and the free-bound gaunt factors
Return type:dict

References

[13]Karzas and Latter, 1961, ApJSS, 6, 167
ChiantiPy.tools.io.masterListInfo(force=False, verbose=False)

Get information about ions in the CHIANTI masterlist.

Returns:masterListInfo – {‘wmin’, ‘wmax’, ‘tmin’, ‘tmax’} Minimum and maximum wavelengths in the wgfa file. Minimum and maximum temperatures for which the ionization balance is nonzero.
Return type:dict

Notes

This function speeds up multi-ion spectral calculations. The information is stored in a pickled file ‘masterlist_ions.pkl’ If the file is not found, one will be created.

ChiantiPy.tools.io.masterListRead()

Read a CHIANTI masterlist file.

Returns:masterlist – All ions in Chianti database
Return type:list
ChiantiPy.tools.io.photoxRead(ions)

Read CHIANTI photoionization .photox files

Returns:{‘lvl1’, ‘lvl2’, ‘energy’, ‘cross’, ‘ref’} – Energy (in Rydbergs) and cross section (in \(\mathrm{cm}^{-2}\))
Return type:dict

Notes

The photox files are not in any released version of the CHIANTI database.

ChiantiPy.tools.io.rrLossRead()

to read the Mao 2017 rr loss parameters [12]

References

[12]Mao J., Kaastra J., Badnell N.R., 2017 Astron. Astrophys. 599, A10
ChiantiPy.tools.io.rrRead(ions, filename=None)

Read CHIANTI radiative recombination .rrparams files

Returns:{‘rrtype’,’params’,’ref’}
Return type:dict
ChiantiPy.tools.io.scupsRead(ions, filename=None, verbose=False)

Read the new format v8 scups file containing the scaled temperature and upsilons from [8].

Parameters:
  • ions (str) – Ion, e.g. ‘c_5’ for C V
  • filename (str, optional) – Custom filename, will override that specified by ions
  • verbose (bool)
ChiantiPy.tools.io.splomRead(ions, ea=False, filename=None)

Read chianti .splom files

Parameters:
  • ions (str) – Ion, e.g. ‘c_5’ for C V
  • ea (bool) – Read .easplom file
  • filename (str, optional) – Custom filename, will override that specified by ions
Returns:

{‘lvl1’, ‘lvl2’, ‘ttype’, ‘gf’, ‘deryd’, ‘c’, ‘splom’, ‘ref’}

Return type:

dict

Notes

Still needed for ionization cross sections

ChiantiPy.tools.io.splupsRead(ions, filename=None, filetype='splups')

Read a CHIANTI .splups file

Parameters:
  • ions (str) – Ion, e.g. ‘c_5’ for C V
  • filename (str, optional) – Custom filename, will override that specified by ions
  • filetype (str, optional) – {psplups,`cisplups`,`splups`} Type of file to read
Returns:

{‘lvl1’, ‘lvl2’, ‘ttype’, ‘gf’, ‘de’, ‘cups’, ‘bsplups’, ‘ref’}

Return type:

dict

ChiantiPy.tools.io.trRead(ionS)

read the files containing total recombination rates .trparams

ChiantiPy.tools.io.twophotonHRead()

Read the two-photon Einstein A values and distribution function for the H sequence.

Returns:{‘y0’, ‘z0’, ‘avalue’, ‘asum’, ‘psi0’}
Return type:dict
ChiantiPy.tools.io.twophotonHeRead()

Read the two-photon Einstein A values and distribution function for the He sequence.

Returns:{‘y0’, ‘avalue’, ‘psi0’}
Return type:dict
ChiantiPy.tools.io.vernerRead()

Reads the photoionization cross-section data from [6].

Returns:{‘pqn’,’l’,’eth’,’e0’,’sig0’,’ya’,’p’, yw’}pqn is the principal quantum number, l is the subshell orbital quantum number, eth (in eV) is the subshell ionization threshold energy; sig0, ya, p, and yw are all fit parameters used in calculating the total photoionization cross-section.
Return type:dict

References

[6]Verner & Yakovlev, 1995, A&AS, 109, 125
ChiantiPy.tools.io.versionRead()

Read the version number of the CHIANTI database

ChiantiPy.tools.io.wgfaRead(ions, filename=None, elvlcname=0, total=False, verbose=False)

Read CHIANTI data from a .wgfa file.

Parameters:
  • ions (str) – Ion, e.g. ‘c_5’ for C V
  • filename (str) – Custom filename, will override that specified by ions
  • elvlcname (str) – If specified, the lsj term labels are returned in the ‘pretty1’ and ‘pretty2’ keys of ‘Wgfa’ dict
  • total (bool) – Return the summed level 2 avalue data in ‘Wgfa’
  • verbose (bool)
Returns:

Wgfa – Information read from the .wgfa file. The dictionary structure is {“lvl1”,”lvl2”,”wvl”,”gf”,”avalue”,”ref”,”ionS”,”filename”}

Return type:

dict

See also

ChiantiPy.tools.archival.wgfaRead()
Read .wgfa file with the old format.
ChiantiPy.tools.io.wgfaWrite(info, outfile=None, minBranch=1e-05, rightDigits=4, maxLvl1=None)

Write data to a CHIANTI .wgfa file

Parameters:
  • info (dict) – Should contain the following keys: ionS, the Chianti style name of the ion such as c_4 for C IV, lvl1, the lower level, the ground level is 1, lvl2, the upper level, wvl, the wavelength (in Angstroms), gf,the weighted oscillator strength, avalue, the A value, pretty1, descriptive text of the lower level (optional), pretty2, descriptive text of the upper level (optiona), ref, reference text, a list of strings
  • outfile (str)
  • minBranch (~numpy.float64) – The transition must have a branching ratio greater than the specified minBranchto be written to the file
ChiantiPy.tools.io.zion2name(z, ion, dielectronic=False)

Convert Z and ion to generic name, e.g. 26, 13 -> fe_13

Parameters:
  • z (int) – the nuclear charge, for example 26 for Fe XIV
  • ion (int) – the ion stage, for example, 14 for Fe XIV

Notes

A duplicate of the routine in ChiantiPy.tools.util but needed by masterList Info TODO: Put in separate module to avoid multiple copies

ChiantiPy.tools.mputil module

Functions needed for standard Python multiprocessing module mspectrum

ChiantiPy.tools.mputil.doFbQ(inQ, outQ)

Multiprocessing helper for ChiantiPy.core.continuum.freeBound

Parameters:
  • inQ (~multiprocessing.Queue) – Ion free-bound emission jobs queued up by multiprocessing module
  • outQ (~multiprocessing.Queue) – Finished free-bound emission jobs
ChiantiPy.tools.mputil.doFfQ(inQ, outQ)

Multiprocessing helper for ChiantiPy.core.continuum.freeFree

Parameters:
  • inQ (~multiprocessing.Queue) – Ion free-free emission jobs queued up by multiprocessing module
  • outQ (~multiprocessing.Queue) – Finished free-free emission jobs
ChiantiPy.tools.mputil.doIonQ(inQueue, outQueue)

Multiprocessing helper for ChiantiPy.core.ion and ChiantiPy.core.ion.twoPhoton

Parameters:
  • inQueue (~multiprocessing.Queue) – Jobs queued up by multiprocessing module
  • outQueue (~multiprocessing.Queue) – Finished jobs

ChiantiPy.tools.sources module

Blackbody temperature calculations

class ChiantiPy.tools.sources.blackStar(temperature, radius)

Bases: object

Calculate blackbody radiation

Parameters:
  • temperature (~numpy.ndarray) – Temperature in Kelvin
  • radius (~numpy.ndarray) – Stellar radius in cm
Variables:
  • Temperature (~numpy.ndarray) – Temperature in Kelvin
  • Radius (~numpy.ndarray) – Stellar radius in cm
  • Incident (~numpy.ndarray) – Blackbody photon distribution
incident(distance, energy)

Calculate photon distribution times the visible cross-sectional area.

Parameters:
  • distance (~numpy.ndarray) – Distance to the stellar object in cm
  • energy (~numpy.ndarray) – Energy range in erg

Notes

This function returns the photon distribution instead of the distribution times the cross-sectional area. Is this correct? Why is the incident photon distribution calculated at all?

ChiantiPy.tools.sources.blackbody(temperature, variable, hnu=1)

Calculate the blackbody photon distribution as a function of energy (hnu = 1) or as a function of wavelength (hnu = 0) in units of \(\mathrm{photons}\,\mathrm{cm}^{-2}\,\mathrm{s}^{-1}\,\mathrm{str}^{-1}\,\mathrm{erg}^{-1}\)

Parameters:
  • temperature (~numpy.float64) – Temperature at which to calculate the blackbody photon distribution
  • variable (~numpy.ndarray) – Either energy (in erg) or wavelength (in angstrom)
  • hnu (int) – If 1, calculate distribution as a function of energy. Otherwise, calculate it as a function of wavelength
Returns:

{‘photons’, ‘temperature’, ‘energy’} or {‘photons’, ‘temperature’, ‘wvl’}

Return type:

dict

ChiantiPy.tools.util module

Utility functions

Notes

Some of these functions can be replaced by roman numeral and periodic table lookup libraries. some functions using os.walk can be replaced by os.path

ChiantiPy.tools.util.between(array, limits)

Find the indices of array corresponding to values in the range given by limits

Parameters:
  • array (‘list` or ~numpy.ndarray`)
  • limits (list, tuple or ~numpy.ndarray` of length 2)
ChiantiPy.tools.util.convertName(name)

Convert ion name string (e.g. ‘fe_13’) to atomic number and ion number.

Parameters:name (str) – the CHIANTI style name for an ion, such as fe_14
Returns:{‘Z’, ‘Ion’, ‘Dielectronic’, ‘Element’, ‘higher’, ‘lower’}higher and lower are the Chianti-style names for the higher and lower ionization stages, respectively.
Return type:dict
ChiantiPy.tools.util.descale_bt(bte, btomega, f, ev1)

Apply excitation descaling of [3] to energy and collision strength

Parameters:
  • bte (array-like) – Scaled energy
  • btomega (array-like) – Scaled collision strength
  • f (array-like)
  • ev1 (array-like)
Returns:

[energy,omega] – Descaled energy and collision strength

Return type:

list

Notes

Need more details here. Not clear which equations are being used.

See also

scale_bt()
Apply scaling to excitation energy and cross-section

References

[3]Burgess, A. and Tully, J. A., 1992, A&A, 254, 436
ChiantiPy.tools.util.descale_bti(bte, btx, f, ev1)

Apply ionization descaling of [9] to energy and cross-sections of [7].

Parameters:
  • bte (array-like) – Scaled energy
  • btx (array-like) – Scaled cross-section
  • f (float) – Scaling parameter
  • ev1 (float) – ionization potential - units determine the output energy units
Returns:

[energy,cross] – Descaled energy and cross-section

Return type:

list

Notes

This is the scaling used and discussed in the Dere (2007) calculation [7] of cross sections. It was derived from similar scalings provided by reference [2]

See also

scale_bti()
Descale ionization energy and cross-section

References

[9]Burgess, A. and Tully, J. A., 1992, A&A, 254, 436
ChiantiPy.tools.util.dilute(radius)

Calculate the dilution factor.

Parameters:radius (array-like) – Distance from the center of a star in units of the stellar radius.

Notes

If radius is less than 1.0, returns 0.

ChiantiPy.tools.util.el2z(els)

Convert elemental symbol to atomic number

Parameters:els (str) – the abreviated element name
Returns:z – the atomic number or nuclear charge of the element
Return type:int
ChiantiPy.tools.util.ion2filename(ions)

Convert ion name string to generic directory-file name. convertName has probably made this redundant

Parameters:ions (str) – the CHIANTI style name for an ion, such as fe_14
Returns:fname – the full file name of the ion directory in the CHIANTI database assumes a top directory from the environmental variable XUVTOP
Return type:str
ChiantiPy.tools.util.listFiles(dir)

Walks the path and subdirectories to return a list of files.

Parameters:dir (str) – the top directory to search subdirectories are also searched
Returns:listname – a list of files in dir and subdirectories
Return type:list

Notes

This can be replaced by functions in os.path, as if 3.4, pathlib is probably better. It is not clear that this function is used anywhere in ChiantiPy

ChiantiPy.tools.util.listRootNames(dir)

Walks the path and subdirectories to return a list of file root names.

Notes

This can be replaced by functions in os.path, as if 3.4, pathlib is probably better. Only seems to be used by

ChiantiPy.tools.util.qrp(z, u)

Calculate \(Q_R^{\prime}(Z,u)\), where \(u=\epsilon/I\) is the impact electron energy in threshold units, from Eq. 2.12 of [4].

Parameters:
  • z (int) – Atomic number
  • u (array-like) – Impact electron energy in threshold units.
Returns:

q – 1s ionization cross-section, \(Q_R^{\prime}(Z,u)\)

Return type:

array-like

Notes

Used for calculations of direct ionization cross-sections of the H and He sequences in ChiantiPy.tools.io.twophotonHRead and ChiantiPy.tools.io.twophotonHeRead, respectively.

References

[4]Fontes, C. et al., 1999, PhRvA, 59, 1329
ChiantiPy.tools.util.scale_bt(evin, omega, f, ev1)

Apply excitation scaling of [8] to energy and collision strength.

Parameters:
  • evin (array-like)
  • omega (array-like)
  • f (array-like)
  • ev1 (array-like)
Returns:

[bte,btomega] – Scaled energy and collision strength

Return type:

list

Notes

Need more details here. Not clear which equations are being used.

See also

descale_bt()
Descale excitation energy and cross-section
ChiantiPy.tools.util.scale_bt_rate(inDict, ip, f=1.7)

Apply ionization descaling of [7], a Burgess-Tully type scaling to ionization rates and temperatures. The result of the scaling is to return a scaled temperature between 0 and 1 and a slowly varying scaled rate as a function of scaled temperature. In addition, the scaled rates vary slowly along an iso-electronic sequence.

Parameters:
  • inDict (dict) – the input dictionary should have the following key pairs: temperature, array-like and rate, array-like
  • ip (float) – the ionization potential in eV.
  • f (float (optional)) – the scaling parameter, 1.7 generally works well

Notes

btTemperature and btRate keys are added to inDict

ChiantiPy.tools.util.scale_bti(evin, crossin, f, ev1)

Apply ionization scaling of [7],[8]_, to energy and cross-section.

Parameters:
  • evin (float) – Energy - same units as ev1
  • crossin (array-like) – Cross-section
  • f (float - the scale factor)
  • ev1 (float) – the ionization potential units - the same as evin
Returns:

[bte,btx] – Scaled energy and cross-section

Return type:

list

Notes

This is the scaling used and discussed in the Dere (2007) calculation [1] of cross sections. It was derived from similar scalings derived in reference [2]

See also

descale_bti()
Descale ionization energy and cross-section

References

[7](1, 2, 3, 4) Dere, K. P., 2007, A&A, 466, 771,
[8](1, 2) Burgess, A. and Tully, J. A., 1992, A&A, 254, 436
ChiantiPy.tools.util.scale_classical(inDict, ip)

Apply the classical scaling to the input data

Parameters:
  • inDict (dictionary) –

    the input dictionary should have the following key pairs

    energy and cross or temperature and rate

  • energy (array-like) – energy values of the cross-section

  • cross (array-like) – a cross-section

  • temperature (array-like)

  • rate (array-like)

  • ip (float) – the ionization potential. Typically in eV.

  • Returns – the following keys are added to inDict

  • ——-

  • {‘csEnergy’, ‘csCross’, ‘ip’} or {‘csTemperature’, ‘csRate’, ‘ip’}

ChiantiPy.tools.util.spectroscopic2name(el, roman)

Convert from spectroscopic notation, e.g. Fe XI to ‘fe_11’.

Parameters:
  • el (str) – Elemental symbol, e.g. Fe for iron
  • roman (str) – Roman numeral spectroscopic symbol
ChiantiPy.tools.util.splomDescale(splom, energy)

Calculate the collision strength for excitation-autoionization as a function of energy.

Parameters:
  • energy (array-like) – In eV
  • splom (dict) – Structure returned by ChiantiPy.tools.io.splomRead
Returns:

omega – Collision strength

Return type:

array-like

ChiantiPy.tools.util.z2element(z)

Convert atomic number z to its elemental symbol.

Parameters:z (int) – The atomic number/nuclear charge
Returns:element – the abbreviated element name
Return type:str
ChiantiPy.tools.util.zion2dir(z, ion, dielectronic=False, xuvtop='')

Convert atomic number and ion number to CHIANTI database directory.

Parameters:
  • z (int) – The atomic number/nuclear charge
  • ion (int) – the ionization stage, 1 for the neutral, 2 for the first ionization stage, …
  • dielectronic (bool, optional)
  • xuvtop (str, optional) – Set different CHIANTI database than the default
Returns:

fname – the CHIANTI directory where the file for the ion specified by z and ion are found

Return type:

str

ChiantiPy.tools.util.zion2filename(z, ion, dielectronic=False, xuvtop='')

Convert nuclear charge/atomic number and ion number to CHIANTI database filename.

Parameters:
  • z (int) – The atomic number/nuclear charge
  • ion (int) – the ionization stage, 1 for neutrals, 2 for singly ionized
  • dielectronic (bool, optional) – whether the ion is the simple dielectronic model
  • xuvtop (str, optional) – the top directory of the CHIANTI database to be used
Returns:

fname – CHIANTI database filename

Return type:

str

ChiantiPy.tools.util.zion2localFilename(z, ion, dielectronic=False)

Convert atomic number and ion number to generic file name with current directory at top.

Parameters:
  • z (int) – The atomic number/nuclear charge
  • ion (int) – the ionization stage, 1 for neutrals, 2 for singly ionized
  • dielectronic (bool, optional)
ChiantiPy.tools.util.zion2name(z, ion, dielectronic=False)

Convert atomic number and ion number to generic name, e.g. (26,13) to ‘fe_13’

Parameters:
  • z (int) – The atomic number/nuclear charge
  • ion (int) – the ionization stage, 1 for the neutral, 2 for the first ionization stage, …
  • dielectronic (bool, optional)
Returns:

thisone – the CHIANTI style ion name, such as ‘fe_13’

Return type:

str

ChiantiPy.tools.util.zion2spectroscopic(z, ion, dielectronic=False)

Convert atomic number and ion number to spectroscopic notation string

Parameters:
  • z (int) – The atomic number/nuclear charge
  • ion (int) – the ionization stage, 1 for neutrals, 2 for singly ionized
  • dielectronic (bool, optional)
Returns:

spect – the spectroscopic notation for the ion, such as Fe XIV

Return type:

str

Module contents

Basic tools and utilities used in ChiantiPy