An Atomic Database for Spectroscopic Diagnostics of Astrophysical Plasmas.
Naval Research Laboratory (USA) -
Universita' degli Studi di Firenze (Italy) -
University of Cambridge (UK)
Rutherford Appleton Laboratory (UK)
December 3, 2003 - CHIANTI v 4.2 released!
Version 4.2 corrects a few errors in the following files:
and improves the wavelengths and energy level values for the following ions:
- O II : o_2.splups
- N VI : n_6.splups
- C V : c_5.splups
- S II : s_2.wgfa
- Si II : si_2.wgfa
- Ne III : ne_3.wgfa
- Al XII : al_12.wgfa
- Fe XIX : fe_19.wgfa, fe_19.splups
- Fe XXIIId : fe_23d.elvlc, fe_23d.wgfa
New data for two innershell transitions for Fe XXIII have been inserted: they
have been calculated using the Flexible Atomic Code developed by Dr. Ming-Feng Gu.
- Ca XVIIId : ca_18d.wgfa
- Fe XX : fe_20.wgfa, fe_20.elvlc
- Fe XXIId : fe_22d.wgfa
- Fe XXIVd : fe_24d.wgfa
- Fe XXIV : fe_24.elvlc, fe_24.wgfa
- Fe XXVd : fe_25d.wgfa
Moreover, collisional data for some missing transitions from metastable levels were
inserted for the following ions: Ar IV, Fe VIII, N I, Ne VII, Ni XIII and Ni XVI.
Details for these changes have been inserted in the comments of each modified file.
The software was corrected for an error that affected all the satellite lines in
the X-rays, a bug in the calculation of the freefree continuum, and a few minor bugs;
many improvements were also added, mostly for Windows-compatibility.
August 8, 2003 - CHIANTI software v 4.1 made available
We have corrected a few minor bugs and added a few improvements. See the HISTORY file for details.
February 6, 2003 - CHIANTI v. 4.02 released!
Since the release of CHIANTI 4.0 we have discovered errors in the ionization
equilibrium (.ioneq) files for the following ions:
Moreover, errors in the original papers were found for the ion fractions of
Ca I and Fe I (Arnaud & Rothenflug 1985).
- 1 - mazzotta_etal.ioneq, mazzotta_etal_ext.ioneq: Ar XII to Ar XIX
- 2 - arnaud_raymond.ioneq, arnaud_raymond_ext.ioneq: Fe VII
- 3 - shull_steenberg.ioneq, shull_steenberg_ext.ioneq: All Fe ions
December 2, 2002 - CHIANTI v. 4.01 released!
Since the release of CHIANTI 4.0 we have discovered errors in
two data files in CHIANTI:
The itoh.dat file is used in the calculation of the bremsstrahlung
continuum radiation. The missing 3-4 transition in Si IX affected
significantly the emissivities of only a few lines in the visible
and of the 258.08 A and 227.36 A lines in the EUV. Corrected versions
of both these files are now distributed in Version 4.01.
- 1 - the "itoh.dat" file was corrupted
- 2 - the file "si_9.splups" was missing the 3-4 transition
In order to improve backward-compatability, we also have included
in Version 4.01 the ion fractions, element abundances and DEM files
from Version 3 in the "version_3" subdirectories within the "ioneq/",
"abund/" and "dem/" directories.
September 2002 - CHIANTI v. 4 released!
We would like to announce the release of the Version 4.0 of the CHIANTI
database for astrophysical spectroscopy. With Version 4, CHIANTI includes
proton excitation rates for most of the ions in the database. New ions have
been inserted, expecially the first neutral species (H I, He I, N I), and data
for many ions have been renewed. Two-photon continuum radiation has been
included, along with a new code for calculating relativistic free-free
continuum. A new feature of the CHIANTI database is the use of 9-point spline
fitting to scaled effective collision strengths, that allows a more accurate
representation of upsilons over large temperature range.
We have completely rewritten the entire software and made it compatible with
Windows NT and VMS. The new software is compatible with the previous versions
of the database.
Atomic Data Updates
The updates contained in Version 4.0 of CHIANTI involve ions emitting at all wavelength
ranges. Updates by iso-electronic sequence are as follows:
- Updates by iso-electronic sequence are as follows:
- Hydrogen sequence
- H I
- Helium sequence
- He I
- Lithium sequence
- C IV, O VI
- Beryllium sequence
- O V, Al X, Si XI, S XIII, Ar XV, Ca XVII, Fe XXIII
- Boron sequence
- Al IX, Si X, S XII, Ar XIV, Ca XVI, Fe XXII
- Carbon sequence
- Ne V, Fe XXI
- Nitrogen sequence
- N I, O II, Mg VI, Al VII, Si VIII, P IX, S X, Ar XII, K XIII, Ca XIV, Ti XVI, Cr XVIII, Mn XIX, Fe XX, Co XXI, Ni XXII, Zn XXIV
- Oxygen sequence
- Ne III, S IX, Fe XIX, Ni XXI
- Fluorine sequence
- Fe XVIII
- Magnesium sequence
- Fe XV
- Phosphorus sequence
- S II, Ar IV, Fe XII
- Scandium sequence
- Fe VI
CHIANTI IDL Procedures Updates
- Completely rewritten
- Compatible with Windows NT and VMS
- Two-photon continuum added
- Free-free modified to include relativistic effects
- effective collision strengths fit
- 9-point spline fit added, to better reproduce effective collision strengths
Dec 20, 2001 - CHIANTI v. 3.03 of the database and software made available
It has recently been pointed out that the CHIANTI (x+y+z)/w intensity ratio of O VII and Si XIII in
the X-ray wavelength range were in disagreement with observations. Disagreements for O VII were moderate,
those for Si XIII were significant. We have discovered a small mistake in the transition energies of
transitions 1-5 and 1-6 in the o_7.splups and si_13.splups files which was the cause of these
disagreements. For this reason, the o_7.splups and si_13.splups files have been corrected (CHIANTI
version 3.03 of the database). We have also corrected a minor error in the 'freefree.pro' routine for
the calculation of the free free continuum. (CHIANTI version 3.03 of the software).
Nov 19 2001 - CHIANTI v. 3.02 of the software made available
We have discovered an error in the calculation of the free-free
continuum in the CHIANTI software package ('freefree.pro'). The error
was associated with the mislabeling of the original data file for the
gaunt factor. The effects of this error are significant only at high
temperatures, where the freefree contribution is most important.
The relevant procedures have been corrected and the whole software
package has been released as v. 3.02.
Apr 30 2001 - CHIANTI v. 3.02 of the database made available
It has recently been pointed out that the intensities of a few O V
lines predicted by the CHIANTI database are in disagreement with
SOHO/SUMER observations on the Sun. The collision rates in the
current (3.01) version of CHIANTI are from distorted wave calculations
from Zhang & Sampson 1992. However, their rates for O V do not appear
to agree well with the other members of the iso-electronic sequence.
It has been found that collisional transition proabilities from
Berrington et al. (1985) provide a better reproduction of the observations.
For this reason, the o_5.splups in the latest version of the CHIANTI
database (version 3.01) has been replaced with the Berrington et al.
(1985) data. The tar files on our web sites have been updated, as
Version 3.02. The only change from version 3.01 is the revised O V
collisional data. Also the files in the SolarSoft package have been updated
with the new data.
Some tests have shown that changes in the emissivities of the O V lines
in the EUV spectral range between 600 A and 800 A are moderate (within 10%),
while the effects on the 1218/1371 line ratio are greater. Electron densities
measured using the 1218/1371 line ratio are now much more in agreement with
estimates from ratios of other ions.
28 November 2000 - new CHIANTI package within SolarSoft made available
reorganised and updated the whole CHIANTI package under SolarSoft:
$SSW/packages/chianti/dbase/ contains the lite version 3.01 of the CHIANTI database
$SSW/packages/chianti/doc/ contains various documentation including
new software notes
replaces the previous CDS software notes #33,37,50 (now obsolete).
$SSW/packages/chianti/idl/ contains all the CHIANTI routines.
In particular, it contains the routines that before could only be found in
$SSW/packages/chianti/idl/extra/ contains some extra routines that Peter Young
contributed. These routines are described in the
28 November 2000 - CHIANTI v. 3.01 of the procedures made available
We have updated some of the CHIANTI IDL routines.
The main changes affect the way the continuum was calculated.
Also, some minor bugs have been fixed.
We have also reorganised the routines into subdirectories,
so you will need to add to your IDL_STARTUP file (if not there
!PATH = '+/data/chianti_pro_v3.01:'+!PATH
!PATH = EXPAND_PATH(!PATH)
The modified routines are:
temperature_ratios, gofnt, setup_ion, conf2n,
density_ratios, read_ioneq, latex_wvl_dem,
28 September 2000 - CHIANTI v. 3.01 made available
Since our announcement of the release of Version 3.0 of the CHIANTI
database we have determined that there are errors in few of the files
in that release. The errors include incorrect collisonal data for the
He II 304 line and two-photon transitions that appear as spectral lines
in some of the helium sequence ions. These files have been corrected
and a new version, Version 3.01, is now available.
If you have downloaded Version 3.0, we highly recommend that you
replace it with Version 3.01.
We regret any inconvenience this has caused you.
1 September 2000 - release of the new CHIANTI v. 3.0
We would like to announce the release of Version 3.0 of the CHIANTI
database for astrophysical spectroscopy. This release extends CHIANTI
into the X-ray wavelength region between 1 and 50 Angstroms.
This has largely been accomplished by including the necessary atomic
data for the hydrogen- and helium-like isoelectronic sequences and
their satellites. In addition, the atomic data for a number of other
ions have also been updated and revised.
In order to include the satellite lines, it has been necessary to
modify the IDL procedures that calculate spectral lines intensities.
Consequently, it is necessary to download both the new data files and
the new set of IDL procedures.
The additions to the database are described in a paper `CHIANTI - an atomic database for emission
lines, IV - Extension to X-ray Wavelengths' by K.P. Dere, E. Landi,
P.R. Young, and G. Del Zanna, and has been submitted to the
Astrophysical Journal Supplement Series.
Atomic Data Updates
The updates contained in Version 3.0 of CHIANTI are primarily concerned
with extending its coverage to include the 1 - 50 Å wavelength
region. The inclusion of emission lines from the hydrogen and helium
isoelectronic sequences and their satellite line and improved models of
highly ionized iron (Fe) ions are the principal ingredients for
achieving this. Below, we list the newly included ions and the ions
which have been modified for improved X-ray coverage.
- Updates by iso-electronic sequence are as follows:
- Hydrogen sequence
- C VI, N VII, O VIII, Ne X, Na XI, Mg XII, Al XIII, Si XIV, S XVI, Ar XVIII, Ca XX, Fe XXVI, Ni XXVIII
- Helium sequence (including satellites to the hydrogen-like lines)
- C V, N VI, O VII, Ne IX, Na X, Mg XI, Al XII, Si XIII, S XV, Ar XVII, Ca XIX, Fe XXV, Ni XXVII
- Lithium sequence satellites to the helium-like lines
- C IV, N V, O VI, Ne VIII, Na IX, Mg X, Al XI, Si XII, S XIV, Ar XVI, Ca XVIII, Fe XXIV, Ni XXVI
- Lithium sequence with inner-shell excitations
- O VI, Ne VIII, Mg X, Al XI, Si XII, S XIV, Ar XVI, Ca XVIII, Fe XXIV, Ni XXV
- Other dielectronic satellites to helium-lines
- Fe XXI, Fe XXII, Fe XXIII
- Beryllium sequence
- Mg IX: R-matrix collision strengths included
- Nitrogen sequence
- Fe XX: R-matrix collision strengths withing the ground configuration
- Neon sequence
- Fe XVII: n=4 levels now included
- Ni XIX: n=4 levels now included
- Silicon sequence
- S III
- Fe XIII: R-matrix collision strengths included for some transitions
- Sulphur sequence
- Fe XI: R-matrix collision strengths included for some transitions
- Chlorine sequence
- Fe X: n=4 and n=5 levels included
CHIANTI IDL Procedures Updates
Procedures for calculating the continuum due to free-free
(bremsstrahlung) and free-bound (radiative recombination) are now
included. Their names are 'FREEFREE' and 'FREEBOUND', respectively. A
procedure ('RAD_LOSS') calculates the total radiative loss rate as a
function of temperature for specified set of abundances and/or
One nice feature initiated in Version 1.03 is that by typing the
name of a procedure, while in IDL, it's correct calling sequence is
We have also renamed some of the utility procedures ('ch_...') so that
they don't conflict with IDL procedures distributed with the Solar
12 April 1999 - CHIANTI version 2 now available
Version 2.0 is now available for downloading at the following site:
Version 2.0 adds atomic data for many of the so called minor
ions, such as fluorine and potassium, not included in the first
version. Because the astrophysical abundances of these elements are
relatively low, only the strongest lines of these elements are
observed. The addition of the minor ions is an important step in our
goal to understand astrophsical spectra in detail. In addition,
Version 2.0 extends the beryllium-like sequence, updates some of the
data in Version 1, and provides an IDL procedure to calculate the
1 March 1999 - CHIANTI Paper III published
Paper III of the CHIANTI series has been published in the Astronomy &
Astrophysics Supplement Series (Vol. 135, 339-346). This paper
describes the updates that will be contained in Version 2 of the
We are still performing checks on the new data and routines contained
in Version 2, but it will be ready for release soon.
20 Feb 1998 - REVISED Ca XVI FILE
The ca_16.splups file has been revised. You can download this
new file below:
18 June 1997 - CHIANTI PAPER II SUBMITTED
The second paper in the CHIANTI series has been submitted to
Astronomy and Astrophysics, and in it we perform a detailed comparison of
theoretical line intensities predicted from the CHIANTI atomic data with
the observed intensities contained in the SERTS-89 active region spectrum.
The paper has been later published in Astronomy & Astrophysics 329, 291-314.
29 April 1997 - VERSION 1.01 RELEASED
We have made the following changes to the CHIANTI data base that is now
released as version 1.01. Because of the number of changes and
correction, we suggest that the complete database should be downloaded
following the standard procedures in the README file. When the version
1.01 tar file is extracted, if will simply overwrite the existing
files. There is no need to remove the version 1.0 files.
Alternately, you could extract it into a new directory, make sure that
your procedures work and then delete the old version.
Changes/corrections to the database are:
- 1. Fe X
- The wavelength of transition 1-5 was corrected to 256.239
- 2. Beryllium sequence
- C III, N IV, O V, Si XI: Peter Young has recalculated the necessary
oscillator strength and A values for these ion and these file have been
- For C III, N IV, O V, Si XI and for Al X, S XIII and Ar XV the A value
for the 1-4 (2s2p 3P1 - 2s2p 3P2) transition was missing and has been
inserted into the version 1.01 files. It begins to dominate the
transition probability to the ground level for high values of Z
begining at Z=8 (Mg XI).
- Relatively small errors in the collision strength files (.splups)
involving the first 10 energy levels have been corrected.
- 3. Boron sequence
- For Si X, the collision strength to energy level 5 has been corrected.
Thanks to Martin Laming for pointing this out.
- For Fe XXII and Ni XXIV, the A values for the 1-2 transitions have been
corrected by roughly an order of magnitude. The correct A values are
Fe XXII: 1.47e+4
Ni XXIV: 3.95e+4
- 4. Fe XX
- The wavelengths and gf and A values are now those from the NIST
database. In particular, some of the strong lines in the EUVE short
wave spectra are better matched with these data. Thanks to Rolf Mewe
for pointing this out.
- 5. Differential emission measures
- In the first release of CHIANTI, the differential emission measures
were defined such that:
Intensity = Integral ( G(T) DEM(T) dlnT )
The advantage of this definition was that it was possible to compare to
isothermal emission measures in a fairly direct fashion. However, the
more standard definition is:
Intensity = Integral ( G(T) DEM(T) dT )
and we have decided to revert to this latter definition. Accordingly,
all the of sample differential emission measures in !xuvtop/dem have
been converted to this definition and the IDL procedures have been
changed to perform the standard integration.
- 6. Ionization equilibria
- The ionization equilibria Arnaud and Raymond (1992) for iron are also
now included in the file 'arnaud_raymond.ioneq' in the standard
directory. The ionization equilibria for all other ions are also
included in this file but the values are taken from Arnaud and
Rothenflug (1985). Thanks to Jeremy Drake for help in producing this
- 7. IDL procedures
- A procedure isothermal.pro, written by Jeff Newmark (GSFC) is now
included in our distribution of CHIANTI IDL procedures. It allows the
calculation of the emitted spectrum at a specified temperature or at
several specified temperatures. The density at each temperature can
also be specified.
- Because of the change in the treatment of differential emission measure
files, it is also necessary to download the latest compressed tar file
of the CHIANTI IDL procedures: CHIANTI_1.02_pro.tar.Z
- The most conventient way to download these files is to go to our web site:
- Please let us know of any problems or difficulties. Also, we believe
that CHIANTI can now be run on VMS machines but needs to be tested.
CHIANTI can also be easily adapted to run on Windows machines (Joan
Schmelz, U. Memphis, has already demonstrated this) and we hope to have
this incorporated into the next release.
- 8. CHIANTI and the Solar Software Library
- CHIANTI is now included as part of the Solar Software Library. The
CHIANTI consortium maintains a set of data files and IDL procedures on
the web and anonymous ftp sites at NRL and Arcetri. We consider these
to be the 'official' CHIANTI files. The Solar Software Library obtains
copies of these files. The data files should be identical. There are
small but significant modifications to the IDL procedures. These
modifications mostly involve the use of IDL system variables by the
CHIANTI IDL procedures and the use of Unix system variables by the
Solar Software Library versions of these programs.
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