NEI Modeling
What do we have? What do we need?
2012.08.09 AtomDB workshop
Hiroya Yamaguchi (CfA)
Fe ion population in CIE (AtomDB v.2.0.2)
Fe16+
Fe26+
Fe24+
Fe25+
Temperature (keV)
APED/APEC
state-of-the-art dataset for
He- & H-like ions of Z<=30
(+ DR lines of Fe)
X-ray-emitting plasma:
T = 106-8 K (0.1-10 keV)
most of atoms are ionized to be
He- or H-like states in CIE
Supernova Remnants = NEI !!
E0102-72
metal-rich, almost neutral
H-dominant (solar abundance) matter
heavy elements are neutral
Shock-heated electrons ionize heavy elements.
t = ne t = 1012 (cm-3 s)
t = 30000 (ne /1cm-3)-1 yr
Supernova Remnants = NEI !!
Fe ion population in NEI (AtomDB v.2.0.2)
typical SNRs
Fe16+
Fe24+
Fe26+
Fe25+
kTe = 20 keV
ne t (cm-3 s)
- Inner-shell process is essentially important for SNRs!
- APEC can calculate ion population, but doesn’t output emission.
SNRs’ spectra of Fe K-shell band
Cr
Fe
Mn
Ni
neutral
3C397
(Type
II)
Ne-like
He-like
W49B
N103B
CasA
0519
0509
Tycho
Kepler
G344
3C397
G349
N132D
RCW86
Kepler
(Type
Ia)
G292
G350
G272
SN1006
Fe Kb
9
6.44 keV
-> Fe XVII-XVIII (Palmeri+03)
Innershell process
- Innershell ionization/excitation
- Fluorescence or Auger (Kaastra & Mewe 93)
… SPEX, XSPEC NEI v.1
Innershell ionization of Be-like ions
Li-like : 1s2s2 (2S) -> wK = 0 (for single-configuration wave function)
in fact, K&M(1993) gave zero values for every Li-like ions.
Configuration interaction (CI) effect cannot be ignored
yCI = c1 1s2s2 (2S) + c2 1s2p2 (2S) ; c2 ~ 0.3 (Gorczyca+2006)
(Gorczyca+06)
wK ≠ 0 !
this work
l
Li-like
K&M93
Fe Ka a energy
(Mendoza+04)
# of electrons
Atomic data for emission above 5 keV
Fe I-XVI
XIX-XVI
Cr, Mn
Palmeri+03a
Mendoza+04
l (Kb)
x-sec (EII)
phenomenological
formula (Haque+06)
x-sec (EIE)
(IRON Project)
Hasogle 08 (thesis)
Palmeri
+03b
Palmeri+08a
(not detected)
Palmeri+12
Kris
l (Ka)
Ni I-XVIII
Gorczyca+03;06
Kris
Ar, Aa
XVII-XIV
(not detected)
DR data for Fe
e.g., Bautista & Badnell 07
Atomic data for emission below 5 keV
Ar, Aa, l (Ka) for all ionization states
Palmeri+08b, Kucas+12: Ne, Mg, Si, S, Ar, Ca
Palmeri+11: Al
Palmeri+12: Na, Cl, Ti, Zn, etc.(Z <= 30)
No longer need Kaastra & Mewe’s data
Lighter elements are usually ionized
to be He-like state.
Si XII
Fe L
S XIV
Ar XVI
Ca XVIII
Kepler
Fe
but a few exception…
0509-67.5: Kb from low-ionized Si
(Warren & Hughes 04)
Tycho: low-ionized Ca (Hwang+98)
Also needed:
Si thru Ca (Ne-like – Li-like)
and L-shell data for Fe, Ca, Ni, …
Recombining plasma
W49B (Ozawa+09)
Fe24+ Ka
What’s the origin?
- collision with dense stellar wind matter
and following adiabatic cooling? (HY+09)
- thermal conduction into cloudy matter?
(Zhou+11)
Abundance & density are important information.
RRC (Fe25+ -> Fe24+)
Recombining plasma
W49B (Ozawa+09)
Fe24+ Ka
RRC (Fe25+ -> Fe24+)
a (recomb rate) : Badnell+06
k = nFe25+ / (nFe26+ + nFe25+ + nFe24+ + …)
We only know nFe25+ /nFe24+ from the RRC/line ratio…
(~ 0.06 in W49B)
Fe16+
Fe24+
Fe26+
Fe25+
Fe ion population in CIE (Mazzotta+98)
We (wrongly) assumed that ion pop in
arbitrary recomb plasma is consistent
to that in CIE plasma with a certain
electron temperature.
then, used k = 0.04 to estimate
Fe abundance and density.
Temperature (keV)
Recombining plasma
Fe26+
Fe24+
CIE
Fe16+
Fe25+
temperature (keV)
kTe = 0.5 keV
ne t (cm-3 s)
Recombining plasma model in XSPEC
must be useful.
We do already have atomic data!
Ionizing
ne t (cm-3 s)
Some difficulty…
Ionizing: kTe, net, abundances, normalization
Recombining: + initial ion population -> 3-dimensional
Summary
Ionizing NEI plasma
- APEC is ready.
- Fluorescence data are completed for all elements (Z <=30)!
except for Kb lines from lowly-ionized atoms
(Kaastra & Mewe’s is no longer needed.)
- EII/EIE rates for Fe & Ni are calculated by Kris & collaborators!
- EII/EIE rates for Cr & Mn would be mostly important now.
- and other abundant elements, Si, S, Ca…
Recombining plasma
- APEC & APED are both (almost) ready.
- one more parameter (init ion pop.) is needed.