multiple ionization of ne, ar, kr, and xe by different ions c. c. montanari 1, j. e. miraglia 1 and...
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Multiple ionization of Ne, Ar, Kr, and Xe by
different ions
Multiple ionization of Ne, Ar, Kr, and Xe by
different ions
C. C. Montanari1, J. E. Miraglia1 and E. Montenegro2
1Instituto de Astronomía y Física del Espacio and Universidad de Buenos Aires, Buenos Aires, Argentina
2Instituto de Física, Universidade Federal do Rio de Janeiro, Brazil
CAARI 2010-Fort Worth
102 103
10-3
10-2
10-1
100
101
102
103M
ultip
le io
niza
tion
cros
s se
ctio
ns (
Mb)
Cavalcanti et al (2002) DuBois (1984) Syage for e+Kr (1992)
Energy (keV/amu)
Kr4+x 10-3
Kr3+x 10-1
Kr2+
Kr+
H+ + Kr
10-18
sec
projectile
photon
3+
photon10-15 sec
10-5
sec
6+
Multiple ionization data includes PCI
PCI=time delayed electron emision
Independent of the projectile
CDW-EIS for multiple ionization of Ne, Ar, Kr, and Xe 7
Table 1. Compilation of experimental photoionization branching ratios.
N e
1s 2s 0 0.0193 1.00 1 0.921 0.00 2 0.0571 0.00 3 0.0028 0.00 4 0.000 0.00
A r
2s 2p 3s 0 0.000 0.005 1.00 1 0.010 0.863 0.00 2 0.890 0.128 0.00 3 0.100 0.003 0.00 4 0.000 0.001 0.00
K r
3s 3p 3d 4s 0 0.00 0.00 0.005 1.00 1 0.01 0.02 0.670 0.00 2 0.12 0.60 0.320 0.00 3 0.66 0.36 0.005 0.00 4 0.21 0.02 0.00 0.00
Xe
4s 4p 4d 5s 0 0.00 0.00 0.00 1.00 1 0.01 0.05 0.80 0.00 2 0.165 0.89 0.20 0.00 3 0.774 0.06 0.00 0.00 4 0.051 0.00 0.00 0.00
In Table 1, we present a rather complete compilation of di¤erent experimentalbranching ratios, of equation (8), for Ne, Ar, Kr and Xe, due to an initial singlevacancy in the -subshell. The vertical sumof each column is equal to 1. In this work,weusetheratios indicated with bold numbers in Table 1.
Auger emission in these targets is energetically possible for initial vacancies fromthedeepest to the subvalence shells [43]. This fact, already mentioned by Krause andCarlson [4, 6] and Saito et al [20], is expressed in Table 1 in thecolumns 2 for Ne, 3for Ar, 4 for Kr and 5 for Xewith = 0 (meaning that single ionization of theseshells does not contributeto PCI [4, 6, 7, 21, 23, 28, 43]).
This is an important point because, in recent works [9, 10, 12, 42], thePCI of Neand Ar targets were included by using the experimental data of Table IV by Carlsonet al [3]. These values represent the charge-state distribution after photoabsortion ofx-rays with energies chosen in order to determine theshell that dominates thevacancy
nF,n = 1
2p
2s
1s
Ne
no of Auger electrons
Single ionization of an electron in
the subshell
Fn
Landers et al 2009, Phys. Rev Lett
Krause & Carlson in the 60s
Brünken et al 2002, Phys. Rev A
Tamenori et al 2004, J. Phys. B
PCI
onlysubvalence electrons
Hikosaka et al 2004, Phys. Rev. AHayaishi et al 2002, J.Phys. B
Direct multiple ionizationDirect multiple ionization
Cross section for ionization of q target electronsCross section for ionization of q target electrons
dbbbPqq )(2
independent electron modelindependent electron model
Binomial distributionBinomial distribution
)1()(... 121
qNi
qi
qqqq
N
i i
iq pp
q
NbP iii
N
single ionization probability per electron single ionization probability per electron for the i atomic subshellfor the i atomic subshell
Multiple ionization including PCIMultiple ionization including PCI
Binomial distributionBinomial distribution
)(... 121 qqqq
N
i
iq ( pi x 1 )
qi
q
NbP
N
)1( qN
ip ii
n Fi,n = 1
Multiple ionization including PCIMultiple ionization including PCI
Binomial distributionBinomial distribution
)(... 121 qqqq
N
i
iq ( pi n Fi,n)
qi
q
NbP
N
)1( qN
ip ii
n Fi,n = 1
P(b)= P PCI
i1s2s…
PCI
including PCI
Number of total emitted electron (direct+PCI) P PCI
1s (2) = P1s (1) F1s,1 + P1s (2)[F1s,0 ]2
Montanari et al J. Phys B 43, 165201 (2010)
Ne
102 103 104
10-3
10-2
10-1
100
101
102
CDW-EIS
CDW-EIS
Cavalcanti (2002) Andersen (1987) DuBois (1984) Schram for e+Ne (1966)
Ne3+x 10-1
ne3+x 10-1
Ne2+
Ne+
M
ulti
ple
ion
iza
tion
cro
ss s
ect
ion
(M
b)
Energy (keV/amu)
H+ + Ne
Born
CDW-EIS
102 10310-5
10-4
10-3
10-2
10-1
100
101
102
CDW-EIS
CDW-EIS
Santos (2001) DuBois (1989)
Energy (keV/amu)M
ultip
le io
niza
tion
cros
s se
ctio
n (M
b)
Ne4+x 10-2
Ne3+x 10-1
Ne2+
Ne+
Born
CDW-EIS
He+ + Ne
100 100010-5
10-4
10-3
10-2
10-1
100
101
102
103
CDW-EIS
CDW-EIS
CDW-EIS
Born
Born
Born, including PCI CDW, including PCI CDW direct DuBois, PRA36.2585 (1987)
Ne+5 x 10-2
Ne+4 x 10-2
Ne+3 x 10-1
Ioni
zatio
n cr
oss
sect
ions
(M
b)
E (keV/amu)
Ne+
Ne+2
He+2 on Ne
without PCI
Born
CDW-EIS
Ar
102 103 10410-4
10-3
10-2
10-1
100
101
102
103
Andersen (1987) Cavalcanti (2002) DuBois (1984)
Ar4+x 10-2
Ar3+x 10-1
Ar2+
Ar+
M
ulti
ple
ion
iza
tion
cro
ss s
ect
ion
s (M
b)
Energy (keV/amu)
H+ + Ar
102 103
10-7
10-6
10-5
10-4
10-3
10-2
10-1
100
101
102
103
He+ + Ar
DuBois (1987) Santos (2002)
Ar5+x 10-5
Mu
ltip
le io
niz
atio
n c
ross
se
ctio
n (
Mb
)
Energy (keV/amu)
Ar4+x 10-3
Ar3+x 10-1
Ar2+
Ar+
Kr
102 10310-4
10-3
10-2
10-1
100
101
102
103
H+ + Kr
Cavalcanti et al (2002) DuBois (1984) Syage for e+Kr (1992)
Mu
ltip
le io
niz
atio
n c
ross
se
ctio
ns
(Mb
)
Energy (keV/amu)
Kr4+x 10-3
Kr3+x 10-1
Kr2+
Kr+
102 10310-7
10-6
10-5
10-4
10-3
10-2
10-1
100
101
102
103
Santos et al (2001) DuBois (1989)
Kr5+x10-5
Energy (keV/amu)
Mu
ltip
le io
niz
atio
n c
ross
se
ctio
n (
Mb
)
Kr4+x10-3
Kr3+x10-1
Kr2+
Kr+
He+ + Kr
Xe
102 10310-3
10-2
10-1
100
101
102
103
Santos et al (2001)
He+ + Xe
Xe3+x 10-2
Xe4+x 10-3
Mu
ltip
le io
niz
atio
n c
ross
se
ctio
n (
Mb
)
Energy (keV/amu)
Xe2+x 10-1
Xe+
102 10310-6
10-5
10-4
10-3
10-2
10-1
100
101
102
103
Cavalcanti (2002) Syage for e+Xe (1992)
Xe5+x 10-5
Energy (keV/amu)
Mu
ltip
le io
niz
atio
n c
ross
se
ctio
ns
(Mb
)
Xe4+x 10-3
Xe3+x 10-1
Xe2+
Xe+
H+ + Xe
Concluding remarks Concluding remarks
Multiple ionization with CDW-EIS and first Born approx.
Concluding remarks Concluding remarks
Multiple ionization with CDW-EIS and first Born approx.
Auger type contributions
Concluding remarks Concluding remarks
Multiple ionization with CDW-EIS and first Born approx.
Auger type contributions
Kr and Xe for the first time (within independent electron model)
Concluding remarks Concluding remarks
Multiple ionization with CDW-EIS and first Born approx.
Auger type contributions
Kr and Xe for the first time (within independent electron model)
Ar and Kr CDW-EIS very good for E>200 keV/amu
H impact, very good!
Born He+, little high for E<70 keV
Ne CDW-EIS good for E>300 keV/amu
Born good even intermediate energies for H+
not so good for He2+
Xe good for H+ impact but not for He+
more experimental data is needed!
Concluding remarks Concluding remarks
Multiple ionization with CDW-EIS and first Born approx.
Auger type contributions
Kr and Xe for the first time (within independent electron model)
Ar and Kr CDW-EIS very good for E>200 keV/amu
H impact, very good!
Born He+, little high for E<70 keV
Ne CDW-EIS good for E>300 keV/amu
Born good even intermediate energies for H+
not so good for He2+
underestimate PCI for H+ + Ne (excitation-ionization channel? Shake-off?)
Xe good for H+ impact but not for He+
more experimental data is needed!
Thank you!
Buenos Aires, Argentina
0 2 4 6 8 100.00
0.02
0.04
0.06
0.08
0.10
0.12
Cro
ss S
ect
ion
(M
b)
Proton energy (MeV)
CDW-EIS for Kshell ionization
H + Ne
102 103 104
10-3
10-2
10-1
100
101
102
Cavalcanti (2002) Andersen (1987) DuBois (1984) Schram for e+Ne (1966)
Ne3+x 10-1
ne3+x 10-1
Ne2+
Ne+
Mu
ltip
le io
niz
atio
n c
ross
se
ctio
n (
Mb
)
Energy (keV/amu)
H+ + Ne
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