anisotropic dielectronic resonances from magnetic-dipole lines yuri ralchenko national institute of...
TRANSCRIPT
![Page 1: Anisotropic dielectronic resonances from magnetic-dipole lines Yuri Ralchenko National Institute of Standards and Technology Gaithersburg, MD, USA ADAS](https://reader038.vdocument.in/reader038/viewer/2022103100/56649f095503460f94c1df53/html5/thumbnails/1.jpg)
Anisotropic dielectronic resonancesfrom magnetic-dipole lines
Yuri Ralchenko
National Institute ofStandards and TechnologyGaithersburg, MD, USA
ADAS Workshop, 2013Supported in part by the Office of Fusion Energy Sciences, U.S. DoE
![Page 2: Anisotropic dielectronic resonances from magnetic-dipole lines Yuri Ralchenko National Institute of Standards and Technology Gaithersburg, MD, USA ADAS](https://reader038.vdocument.in/reader038/viewer/2022103100/56649f095503460f94c1df53/html5/thumbnails/2.jpg)
Analyzing 10,000-eV dielectronic resonanceswith 80-eV forbidden lines
Yuri Ralchenko
National Institute ofStandards and TechnologyGaithersburg, MD, USA
ADAS Workshop, 2013Supported in part by the Office of Fusion Energy Sciences, U.S. DoE
![Page 3: Anisotropic dielectronic resonances from magnetic-dipole lines Yuri Ralchenko National Institute of Standards and Technology Gaithersburg, MD, USA ADAS](https://reader038.vdocument.in/reader038/viewer/2022103100/56649f095503460f94c1df53/html5/thumbnails/3.jpg)
Yu. Ralchenko & J.D. GillaspyPhysical Review A 88, 012506 (2013)
![Page 4: Anisotropic dielectronic resonances from magnetic-dipole lines Yuri Ralchenko National Institute of Standards and Technology Gaithersburg, MD, USA ADAS](https://reader038.vdocument.in/reader038/viewer/2022103100/56649f095503460f94c1df53/html5/thumbnails/4.jpg)
Radiative recombination
Continuum
Bound states
𝐴( 𝑍+1 )+¿+𝑒 → 𝐴𝑍 +¿+h𝜈 ¿¿
Ion recombined
![Page 5: Anisotropic dielectronic resonances from magnetic-dipole lines Yuri Ralchenko National Institute of Standards and Technology Gaithersburg, MD, USA ADAS](https://reader038.vdocument.in/reader038/viewer/2022103100/56649f095503460f94c1df53/html5/thumbnails/5.jpg)
DR step 1: dielectronic capture
Continuum
Bound states
Resonant process!
𝐴( 𝑍+1 )+¿+𝑒 → 𝐴𝑍 +∗∗¿
![Page 6: Anisotropic dielectronic resonances from magnetic-dipole lines Yuri Ralchenko National Institute of Standards and Technology Gaithersburg, MD, USA ADAS](https://reader038.vdocument.in/reader038/viewer/2022103100/56649f095503460f94c1df53/html5/thumbnails/6.jpg)
Continuum
Bound states
Dielectronic capture + autoionization= no recombination
DC and AI aredirect and inverse
![Page 7: Anisotropic dielectronic resonances from magnetic-dipole lines Yuri Ralchenko National Institute of Standards and Technology Gaithersburg, MD, USA ADAS](https://reader038.vdocument.in/reader038/viewer/2022103100/56649f095503460f94c1df53/html5/thumbnails/7.jpg)
DR step 2: radiative stabilization
Continuum
Bound states
𝐴( 𝑍+1 )+¿+𝑒 → 𝐴𝑍 +∗∗ → 𝐴𝑍 +∗+h𝜈¿
Stabilizing transition:Mostly x-rays
![Page 8: Anisotropic dielectronic resonances from magnetic-dipole lines Yuri Ralchenko National Institute of Standards and Technology Gaithersburg, MD, USA ADAS](https://reader038.vdocument.in/reader038/viewer/2022103100/56649f095503460f94c1df53/html5/thumbnails/8.jpg)
Dielectronic recombination in plasmas
Z
Z+1…
Maxwellian
Electrons are presentat all energies
(Infinite) Series of transitions areto be accounted for
DR
![Page 9: Anisotropic dielectronic resonances from magnetic-dipole lines Yuri Ralchenko National Institute of Standards and Technology Gaithersburg, MD, USA ADAS](https://reader038.vdocument.in/reader038/viewer/2022103100/56649f095503460f94c1df53/html5/thumbnails/9.jpg)
DR measurements on EBITs
EBIT electronbeam
extractedions
Is ionization distribution the sameinside and outside the trap?..
NO!
1. Extract ions2. Measure ionization distribution
Beam energy
time
ER
ER
ER
Fast beam ramping
DR energy generally does not coincide with the energy of max abundance
![Page 10: Anisotropic dielectronic resonances from magnetic-dipole lines Yuri Ralchenko National Institute of Standards and Technology Gaithersburg, MD, USA ADAS](https://reader038.vdocument.in/reader038/viewer/2022103100/56649f095503460f94c1df53/html5/thumbnails/10.jpg)
DR resonances with M-shell (n=3) ions
LMN resonances:L electron into M,free electron into N
1s22s22p63s23p63dn
![Page 11: Anisotropic dielectronic resonances from magnetic-dipole lines Yuri Ralchenko National Institute of Standards and Technology Gaithersburg, MD, USA ADAS](https://reader038.vdocument.in/reader038/viewer/2022103100/56649f095503460f94c1df53/html5/thumbnails/11.jpg)
Calculation of LMn DR strength: Ca-like 3d2 W54+
2s1/2 3d2p1/2 3d2p3/2 3d
e 3de 4le 5l
1s2(2s2p)83s23p63d + e 1s2(2s2p)73s23p63d2nl
Relativistic model potential+ QED corrections(Flexible Atomic Code, Gu 2008)
![Page 12: Anisotropic dielectronic resonances from magnetic-dipole lines Yuri Ralchenko National Institute of Standards and Technology Gaithersburg, MD, USA ADAS](https://reader038.vdocument.in/reader038/viewer/2022103100/56649f095503460f94c1df53/html5/thumbnails/12.jpg)
Strategy1. Scan electron beam
energy with a small step (a few eV)
2. When a beam hits a DR, ionization balance changes
3. Both the populations of all levels within an ion and the corresponding line intensities change as well
4. Measure line intensity ratios from neighbor ions and look for resonances
5. EUV lines: forbidden magnetic-dipole lines within the ground configuration
A(E1) ~ 1015 s-1
A(M1) ~ 105-106 s-1
I = NAE (intensity)
Ionization potential
Ca-like W54+
![Page 13: Anisotropic dielectronic resonances from magnetic-dipole lines Yuri Ralchenko National Institute of Standards and Technology Gaithersburg, MD, USA ADAS](https://reader038.vdocument.in/reader038/viewer/2022103100/56649f095503460f94c1df53/html5/thumbnails/13.jpg)
Beam energy: 0.1 keV – 30 keVBeam resolution: ~50 eVBeam current: ≤ 150 mABeam radius: ~30 μmElectron density: ~1012 cm-3
Can produce > 60-timesionized atoms
Ar, Kr, Xe, Sn, Ti, Sm, Gd, Dy,Er, Hf, Ta, W, Pt, Au, Bi,…
NIST Electron Beam Ion Trap1.0
0.8
0.6
0.4
0.2
0.0
No
rma
lize
d C
ross
Se
ctio
n
140120100806040200
Speed [106
m/s]
EBIT Electron Beam (width x10) Maxwell-Boltzmann distribution
8 keV
x10
Monoenergetic beam allows one to “touch” dielectronic resonances
![Page 14: Anisotropic dielectronic resonances from magnetic-dipole lines Yuri Ralchenko National Institute of Standards and Technology Gaithersburg, MD, USA ADAS](https://reader038.vdocument.in/reader038/viewer/2022103100/56649f095503460f94c1df53/html5/thumbnails/14.jpg)
Yu. Ralchenko et al, Phys. Rev. A 83, 032517 (2011)
Almost all lines are M1Good statisticsIsolated lines
Pair of lines:(a) within 3d in K-like W55+ (b) within 3d2 in Ca-like W54+
EUV spectrum of W47+-W56+: M1 lines within 3dn ground configurations
![Page 15: Anisotropic dielectronic resonances from magnetic-dipole lines Yuri Ralchenko National Institute of Standards and Technology Gaithersburg, MD, USA ADAS](https://reader038.vdocument.in/reader038/viewer/2022103100/56649f095503460f94c1df53/html5/thumbnails/15.jpg)
[Ca]/[K]
𝑊 54+¿3 𝑑2𝐽 =2 −3𝑑 2
𝐽=3
𝑊 5 5+¿3 𝑑3/ 2 −3𝑑5 /2 ¿¿
![Page 16: Anisotropic dielectronic resonances from magnetic-dipole lines Yuri Ralchenko National Institute of Standards and Technology Gaithersburg, MD, USA ADAS](https://reader038.vdocument.in/reader038/viewer/2022103100/56649f095503460f94c1df53/html5/thumbnails/16.jpg)
[Ca]/[K]:
𝑊 54+¿3 𝑑2𝐽 =2 −3𝑑 2
𝐽=3
𝑊 5 5+¿3 𝑑3/ 2 −3𝑑5 /2 ¿¿
THEORY:no DR
Modeling: CR code NOMAD, atomic data from FAC
![Page 17: Anisotropic dielectronic resonances from magnetic-dipole lines Yuri Ralchenko National Institute of Standards and Technology Gaithersburg, MD, USA ADAS](https://reader038.vdocument.in/reader038/viewer/2022103100/56649f095503460f94c1df53/html5/thumbnails/17.jpg)
[Ca]/[K]
𝑊 54+¿3 𝑑2𝐽 =2 −3𝑑 2
𝐽=3
𝑊 5 5+¿3 𝑑3/ 2 −3𝑑5 /2 ¿¿
THEORY:no DR
![Page 18: Anisotropic dielectronic resonances from magnetic-dipole lines Yuri Ralchenko National Institute of Standards and Technology Gaithersburg, MD, USA ADAS](https://reader038.vdocument.in/reader038/viewer/2022103100/56649f095503460f94c1df53/html5/thumbnails/18.jpg)
[Ca]/[K]
𝑊 54+¿3 𝑑2𝐽 =2 −3𝑑 2
𝐽=3
𝑊 5 5+¿3 𝑑3/ 2 −3𝑑5 /2 ¿¿
THEORY:no DRisotropic DR
Non-Maxwellian (40-eV Gaussian) collisional-radiative model: ~10,500 levels
![Page 19: Anisotropic dielectronic resonances from magnetic-dipole lines Yuri Ralchenko National Institute of Standards and Technology Gaithersburg, MD, USA ADAS](https://reader038.vdocument.in/reader038/viewer/2022103100/56649f095503460f94c1df53/html5/thumbnails/19.jpg)
[Ca]/[K]
𝑊 54+¿3 𝑑2𝐽 =2 −3𝑑 2
𝐽=3
𝑊 5 5+¿3 𝑑3/ 2 −3𝑑5 /2 ¿¿
THEORY:no DRisotropic DRanisotropic DR
atomic level degenerate
magneticsublevels
Jm=-J
m=+J
Impact beam electrons are monodirectional
Non-Maxwellian (40-eV Gaussian) collisional-radiative model: ~10,500 levels
![Page 20: Anisotropic dielectronic resonances from magnetic-dipole lines Yuri Ralchenko National Institute of Standards and Technology Gaithersburg, MD, USA ADAS](https://reader038.vdocument.in/reader038/viewer/2022103100/56649f095503460f94c1df53/html5/thumbnails/20.jpg)
[Ca]/[K]
𝑊 54+¿3 𝑑2𝐽 =2 −3𝑑 2
𝐽=3
𝑊 5 5+¿3 𝑑3/ 2 −3𝑑5 /2 ¿¿
THEORY:no DRisotropic DRanisotropic DR
atomic level degenerate
magneticsublevels
Jm=-J
m=+J
Impact beam electrons are monodirectional
Non-Maxwellian (40-eV Gaussian) collisional-radiative model: ~18,500 levels
![Page 21: Anisotropic dielectronic resonances from magnetic-dipole lines Yuri Ralchenko National Institute of Standards and Technology Gaithersburg, MD, USA ADAS](https://reader038.vdocument.in/reader038/viewer/2022103100/56649f095503460f94c1df53/html5/thumbnails/21.jpg)
[Ca]/[K]
𝑊 54+¿3 𝑑2𝐽 =2 −3𝑑 2
𝐽=3
𝑊 5 5+¿3 𝑑3/ 2 −3𝑑5 /2 ¿¿
2p3/2 3de 4l
![Page 22: Anisotropic dielectronic resonances from magnetic-dipole lines Yuri Ralchenko National Institute of Standards and Technology Gaithersburg, MD, USA ADAS](https://reader038.vdocument.in/reader038/viewer/2022103100/56649f095503460f94c1df53/html5/thumbnails/22.jpg)
One EBIT run, several ions…
Can=4 Sc Ti
![Page 23: Anisotropic dielectronic resonances from magnetic-dipole lines Yuri Ralchenko National Institute of Standards and Technology Gaithersburg, MD, USA ADAS](https://reader038.vdocument.in/reader038/viewer/2022103100/56649f095503460f94c1df53/html5/thumbnails/23.jpg)
Where are the 10-keV photons?..
2p53s23p63dn+14l
2s1/22p1/2
2p3/2
3s3p
3d
4s 4p 4d 4f
~8keV~9keV
~11keV
![Page 24: Anisotropic dielectronic resonances from magnetic-dipole lines Yuri Ralchenko National Institute of Standards and Technology Gaithersburg, MD, USA ADAS](https://reader038.vdocument.in/reader038/viewer/2022103100/56649f095503460f94c1df53/html5/thumbnails/24.jpg)
X-ray emission (Ge detector)
2p53/2-4l
2p53/2-3d
2p53/2-3s
B and C: horizontal
A: slant
n>0 transitions into the 2p3/2 hole
![Page 25: Anisotropic dielectronic resonances from magnetic-dipole lines Yuri Ralchenko National Institute of Standards and Technology Gaithersburg, MD, USA ADAS](https://reader038.vdocument.in/reader038/viewer/2022103100/56649f095503460f94c1df53/html5/thumbnails/25.jpg)
Conclusions
•A new in situ method to measure multi-keV dielectronic resonances in 3dn ions using ratios of EUV magnetic-dipole lines
•First resolved measurements of LMN resonances in ~55-times ionized W
•CR modeling shows importance of anisotropic effects on ionization balance
•Isolated resonances allow determination of the beam width