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VOTada VO Tools and Atomic Data for Astrophysics. Giulio Del Zanna. TRACE image of solar coronal loops. The VOTADA project aims at providing accurate atomic data and derived products/tools for astrophysical applications within the Astrogrid (PPARC-UK) and VO. Peter Young (RAL) - PowerPoint PPT Presentation
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UCL DEPT. OF SPACE & CLIMATE PHYSICS SOLAR & STELLAR PHYSICS GROUP
VOTada VO Tools and Atomic Data for AstrophysicsAtomic Data for Astrophysics
Giulio Del Zanna
TRACE image of solar coronal loops
DAMTP, Feb 2007
• The VOTADA project aims at providing accurate atomic data and derived products/tools for astrophysical applications within the Astrogrid (PPARC-UK) and VO.
• Peter Young (RAL)• Helen Mason (Univ. Cambridge)• Silvia Dalla (Univ. Manchester)• Kevin Benson (UCL/MSSL)
DAMTP, Feb 2007
The CHIANTI database• Collaboration between UK, US and Italy
– K. Dere, E. Landi, H. Mason, G. Del Zanna, M. Landini, P. Young
• Freely available. First release in 1996, regularly updated.
• Provides all atomic data necessary for modelling coronal spectra, but also used for a wide range of astrophysical objects (Chandra, XMM--Newton, FUSE, HST).
• Included in many other spectral codes such as:
• XSTAR (HEASARC/GSFC -- USA); APED/ATOMDB (CfA, Harvard-Smithsonian --USA); XSPEC (HEASARC/GSFC -- USA); ISIS (MIT -- USA);
• PINTofALE (CfA, Harvard-Smithsonian -- USA); Arcetri Spectral Code
• (Italy).
Over 800 citations
DAMTP, Feb 2007
CHIANTI atomic package
Data, programs, User Guides
www.chianti.rl.ac.uk
DAMTP, Feb 2007
CHIANTI Software
• CHIANTI IDL software takes the atomic data and calculates line+continuum emissivities. Line emissivities are:
jijij AN
• Obtain densities, temperatures and elemental abundances from e.g. line ratios.
• Derive DEM curves.• Create synthetic spectra to be compared to observed ones• Create synthetic broad-band images• Calculate instrument response functions• Calculate radiative losses
jiee
jij AN
N
N
N
N
N
N
N
N )H(
)H(
)Fe(
)Fe(
)XII Fe(
XII) (Fe
F(T) Ab(Fe) 0.83
DAMTP, Feb 2007
DAMTP, Feb 2007
CHIANTI data files
• CHIANTI is distributed within Solarsoft – $SSW/packages/chianti
• For each ion there is a directory, e.g.,dbase/fe/fe_12• 4 main files for each ion, e.g.,
fe_12.elvlc Energy levels (theoretical, observed), level descriptions
fe_12.wgfa Radiative decay rates, gf values, wavelengths
fe_12.splups spline fits to the Maxwellian-averaged e- collision strengths
DAMTP, Feb 2007
• CHIANTI emissivities are currently calculated for• equilibrium plasmas (collisional, optically-thin), but
non-equilibrium, non-Maxwellian plasmas will soon be included.
• building a database of radiative and dielectronic
recombination rates, as well as collisional and photo-ionization cross-sections
DAMTP, Feb 2007
1. -Written CHIANTI data in a way to be imported into a MySQL database.
Wavelength, A-value, gf-value configuration, nLSJ, observed, theoretical energy of upper and lower levels
1. -Use DAL Toolkit to install a SLAP server (DMMapper can translate from CHIANTI data model to Line data model)
2. -Data will appear automatically in VOSpec, once registered
DAMTP, Feb 2007
Summary
DAMTP, Feb 2007
DAMTP, Feb 2007
Scattering calculations: Fe XII
From Flower (1977) until Storey Del Zanna, Mason (2005),serious problems with the Fe XII
spectrum were present.
EUV
4S3/2, 2D3/2, 2D5/2, 2P1/2, 2P3/2
2D3/2
4P1/2
4P3/2
2P1/2
SO
•Iron Project•UK Rmax network – new PPARC proposal (APAP network)
DAMTP, Feb 2007
Fe XII: electron densities now 10 times lower.
Of the lowest 41 levels:
15 were not known (identified 12)
6 were incorrectly assigned
14 values revised
21/58 new transitions identified/revised
(Del Zanna & Mason 2005)
DAMTP, Feb 2007
Whittoeft, Badnell,Del Zanna et al. (2006)Del Zanna (2006)
Atomic data make a difference! Fe XII Fe XVIII
Storey, Del Zanna et al. (2005)
Del Zanna & Mason (2005)
DAMTP, Feb 2007
• Hydrodynamic equations in 1-D
0)(
vst
s
Pgv
sv
t
||2 )()(
),(),(])[( 2
5
|| tsEtsEs
TT
svgvPE
st
ERH
Conservation of Mass Momentum
Energy
Y
Z
iiiR YYAbNE
1
1
2 )(83.0
)()( 1111 iiiiiiiiii YRYIYRYINvY
st
Y
Radiative lossess
Time-dependent ionisation
Eq. state
TknP e B2
Heating rateClassical conduction
DAMTP, Feb 2007
Diagnostics of chemical abundances
Widing & Feldman (1992)
Del Zanna et al. (2003)Te of maximum emissivity in ionization equilibrium
Actual Te
Incorrect abundances (by a factor of 10) can be obtained if approximations are used.
Plumes in coronal holes
)()( TeGjiYAb
Iobs
dTTeGji
Iobs
)(
FIP=10
FIP=0