Документ взят из кэша поисковой машины. Адрес оригинального документа : http://hea-www.harvard.edu/PINTofALE/doc/LDB_CHIANTI.howto Дата изменения: Mon Aug 2 20:58:05 2010 Дата индексирования: Tue Oct 2 01:49:42 2012 Кодировка:

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HOW TO CREATE THE CHIANTI LINE EMISSIVITY DATABASE 01Aug2010

NOTES:
a. This version of PINTofALE is designed for use with CHIANTI v6
b. For convenience, we have also provided a tar file containing the
CHIANTI line emissivities computed at various densities, in
http://hea-www.harvard.edu/PINTofALE/PoA_chianti_2.0.tar.gz
The following instructions should be used if you prefer to use a
different grid, or need the emissivities computed at constant
pressure, etc.

1. Obtain the CHIANTI dataset from

http://www.chiantidatabase.org/

and install it, say at /foo/bar/CHIANTI/

2. Start IDL and initialize the variables

WMN=0.0 ;minimum wavelength [Ang] in output database
WMX=3000.0 ;maximum wavelength [Ang] in output database
CHIDIR='/foo/bar/CHIANTI/dbase/'
;full path to CHIANTI installation,
; _including_ the "dbase"
OUTDIR='/foo/bar/PINTofALE/emissivity/chianti'
;full path to output database location,
; _without_ a trailing "/"

NE_MIN=8.0 ;minimum log10 density [cm^-3] in database
NE_MAX=15.0 ;maximum log10 density [cm^-3] in database
D_NE=1.0 ;grid resolution in log10 electron density

P_MIN=13.0 ;minimum log10 pressure [cm^-3 K] in database
P_MAX=20.0 ;maximum log10 pressure [cm^-3 K] in database
D_P=1.0 ;grid resolution in log10 pressure (set to -1
;to avoid making constant pressure database)

These variables set up the IDL script that will extract line
emissivities from CHIANTI and write them out in a fast-access
form. Two directories are created, one containing emissivities
calculated at constant densities ("chiantiD") and one at constant
pressures ("chianti"). Since each of these databases take up 176
MB, in order to save space it may be advantageous to avoid making
the constant-pressure database. This may be achieved simply by
setting D_P=-1.0 in the above initialization.

3. Run the script MK_LCOOL_CHIANTI

.run mk_lcool_chianti

This will take a few hours to complete, but does not need any
intervention. The CHIANTI dataset is read in and emissivities
are computed for each line at a variety of densities, pressures,
and temperatures, which are then saved in a PINTofALE readable
format.

4. To compare PINTofALE calculations with CHIANTI's over some
wavelength range of interest, use the example script chipoacom.
Start IDL afresh,

IDL> .run initale
PoA> v_OUTPS = 'chi42poa.ps'
PoA> .run chipoacom

The output in the postscript file will show the spectra calculated
by PINTofALE and CHIANTI, followed by the fractional differences
between the two. If all goes well, you should see only horizontal
green line at Y=0 in the fractional difference plots.

5. CHIANTI has grown considerably over time, and now the full database
in PINTofALE takes up more than a gigabyte. This database can be
compressed to include only locally strong lines -- i.e., lines which
are within a set threshold (e.g., 1%) of the strongest lines in the
vicinity (e.g., with 1AA). The example script chiompress illustrates
how to extract such lines and write them out to a smaller database.

IDL> .run initale
PoA> chifulldir=!LDBDIR
PoA> outdir='/foo/bar/emissivity/chiompress'
PoA> hwdth=1 ;moving window half-width [Angstrom]
PoA> dynrng=1e2 ;dynamic range threshold within window
PoA> .run chiompress

This will create the shrunken line database directory outdirD/ and
a postscript file that displays which lines were kept and which were
not, for each element.

NOTE: Any errors in these computations are due to us, and
are not the responsibility of the CHIANTI software team.
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