Download Momentum Imaging in Atomic Collision Physics

Momentum Imaging in Atomic
Collision Physics
•
BREADTH : MICROMODEL OF ICPEAC
•
WHAT IS IT?
•
FOCUS: DOUBLE IONIZATION
ICPEAC 2003
BREADTH: MODEL OF ICPEAC ?
OF MOLECULES
WHICH EXPLODE
WITH SYNCHROTRON
RADIATION
EVENT BY EVENT
MOMENTUM IMAGING
ION-ATOM COLLISIONS
IONIZATION
WITH INTENSE LASER
PULSES
ICPEAC 2003
COLLISIONS IN MOTS
USE TO ANALYZE MOT
Conceptual COLTRIMS
Projectile
Electron
Recoil
Single detectors
p
p’
p
p
Imaging
p
E
p
p’
p
B
THE DETECTOR
Cold Target Recoil Ion Momentum Spectroscopy
The detector
Well, not
really, but
the idea is
similar
CMS detector at Fermilab
THE BASIC DETECTOR
COILS
REACTION
E
B
P ALONG BEAM FROM TIME
P TRANSVERSE FROM POSITION
POSITION AND
TIME SENSITIVE
DETECTORS
CHOOSE ONE OF EACH
BEAM
LASER BEAM
TARGET
DETECTOR
COILS
E
B
SYNCHROTRON
RADIATION
PHOTON BEAM
(SUPERSONIC)
JET
POSITION AND
TIME SENSITIVE
DETECTORS
l/4
l/4
l/4
MOT
l/4
ION BEAM
CLASSIC CONFIGURATION : IONS ON
JETS
COILS
POSITION AND
TIME SENSITIVE
DETECTORS
E
B
SUPERSONIC
JET
ION BEAM
VARIATION ONE: PHOTONS ON JETS
COILS
POSITION AND
TIME SENSITIVE
DETECTORS
E
B
SYNCHROTRON
RADIATION
PHOTON BEAM
SUPERSONIC
JET
VARIATION TWO: LASERS ON JETS
COILS
POSITION AND
TIME SENSITIVE
DETECTORS
E
B
LASER BEAM
SUPERSONIC
JET
VARIATION THREE: ION BEAMS ON MOT
COILS
POSITION AND
TIME SENSITIVE
DETECTORS
l/4
E
l/4
B
l/4
ION BEAM
l/4
MOT
VARIATION FOUR: LASER BEAMS ON MOT
COILS
POSITION AND
TIME SENSITIVE
DETECTORS
l/4
E
l/4
B
l/4
LASER BEAM
l/4
MOT
Some typical momenta in the
interaction
Momentum carried by photon:
E/c , c=137 in au. : 8 x 10 –3 a.u.
for a 300 eV photon.
Momentum carried by a 10 eV electron ejected from atom:
0.86 a.u.
Momentum carried by 5 eV molecular C+ fragment:
90 a.u.
Momentum of thermal He atom at 300 K / Rb atom at 250 x 10 -6 K
4 a.u.
.017 a.u.
Experimental resolution:
Recoils < 0.2 a.u.
Electrons
< 0.05 a.u.
The physics
Low energy collisions:
Capture by highly charged ions
Ionization : continuum electrons
High energy collisions:
Large Z/v
Single electron processes
Small Z/v…photons
Large Z/v
Two electron processes
Small Z/v…photons
Fixed in space molecules:
inner shells
Intense laser
Electric field caused by a passing Xe 26+ ion
Field from 25+ ion at v=.05 with b=7 a.u.
Electric Field (a.u.)
0.6
Over barrier to make..
H2
0.4
++
0.2
H2
0.0
-500
+
0
Time (a.u.)
500
Q spectra for capture from He by Ar 16+ ions
M.Abdallah, W.Wolff, H.E.Wolf,
E.Y.Kamber,M.Stockli and C.L.Cocke,
Phys.Rev.A 58, 2911(1998).
1
Ar
Energy (a.u.)
0
16+
+ He
-1
n=9
n=8
-2
n=7
n=6
-3
n=5
Ar
15+
+ He
-4
0
10
20
R (a.u.)
30
Q value versus Auger electron energy in double capture
O 6+ on He at 138 keV
O 6+ + He
O 4+ (nl,n’l’) + He ++
O 5+ + e Auger
G. Laurent , M. Tarisien , X. Flechard , et al., Nucl.
Inst. Meth. (2003, to be published).
High resolution Q value spectra from capture by Ne 7+ from He at 0.35 a.u.
pz of recoil
D.Fischer, B.Feuerstein,
R.D.DuBois,
R.Moshammer,
J.R.Crespo-Lopez-Urrutia
et al., J. Phys. B 35, 1369
(2002).
Momentum resolution
0.07 a.u.
Q-value spectra from Ar 8+ on atomic
hydrogen
Experiment:Erge EdguFry, Ph.D.Thesis
Theory: Lee and Lin,
Close coupling AO
700
600
Theory
8.5
19.6
43.4
71.6
13.2
6.3
8.9
28.4
500
counts
Relative populations (%)
Experiment
5s
8.1
5p
14.6
5dfg
29.8
Sum 5 52.5
6s
3.3
6p
32.5
6dfg
10.4
Sum 6 46.3
8+
Ar +H, v=0.32 a.u. fd p s n=5
n=6
fd ps
800
n=7
400
300
n=8
200
100
0
-10
0
10
20
Q(eV)
30
40
50
MOTRIMS Van der Poel
Frauhenhofer diffraction in capture from Na by Li+
Dq ~ 10 -6 rad
M.Van der Poel Ph.D. thesis
Orsted Institute, Univ. Copenhagen
M. van der Poel, C. V. Nielsen, M.-A. Gearba, and N.
Andersen, Phys. Rev. Lett. 87, 123201 (2001).
MOTRIMS results: O 6+ on Na capture
Experiment
CTMC
J.W. Turkstra, R. Hoekstra, S. Knoop, D. Meyer, R.
Morgenstern, and R. E. Olson, Phys.Rev.Lett. 87, 123202
(2001).
KSU MOTRIMS Cs+
R. Brédy, H. Nguyen, H. A. Camp, X. Flechard and B. D.
DePaola, J.R.Macdonald Laboratory, Kansas State Univ.
+
6 keV Cs +Rb(5s),Rb(5p)
*
Cs +Rb
+
5s-6s
2.000
0.0010
3.295
5.429
Scattering Angle (rad)
8.944
5p-5d
14.74
5p-6s
5s-6p
24.28
40.00
5p-6p
65.90
0.0005
108.6
178.9
294.7
485.6
800.0
-2.5
-2.0
-1.5
-1.0
-0.5
0.0
0.5
Q value (eV)
1.0
1.5
2.0
2.5
KSU MOTRIMS Na+
R. Brédy, H. Nguyen, H. A. Camp, X. Flechard and B. D.
DePaola, J.R.Macdonald Laboratory, Kansas State Univ.
Na+ capturing from Rb(5s) and Rb(5p)
5p-3p
5s-3p
15000
Capture from Rb(5s)
Capture from Rb(5p)
Na(3p)
Na(3p)
5.000
6.776
9.183
12.44
16.86
22.85
30.97
41.97
56.88
77.09
104.5
141.6
191.9
260.0
20
15
laser on
Counts
TAC Time (s)
10000
Na(4s)
5000
Na(3s)
10
5
laser off
X 10
Na(3d)
Na(4d)
0
-3
-2
-1
0
1
2
3
Q Value (eV)
0
-3
-2
-1
0
Q value (eV)
1
2
T. G. Lee, H. Nguyen, X. Flechard, B. D.
DePaola, and C. D. Lin
Phys. Rev. A 66, 042701 (2002)
The physics
Low energy collisions:
Capture by highly charged ions
Ionization
Ionization:: continuum electrons
High energy collisions:
Large Z/v
Single electron processes
Small Z/v…photons
Large Z/v
Two electron processes
Small Z/v…photons
Fixed in space molecules:
inner shells
Intense laser
Continuum electrons for fixed scattering plane
5 keV
Doerner et al,
Phys.Rev.Lett. 77,
4520 (1997)
p on He
Projectile
10 keV
Recoil
15 keV
In plane
Electron spectra for He+ on He
1 eV
+
10 keV/u He + He (v p = 0.64 a.u.)
0.0
0.5
1.0
-1.0 -0.5 0.0 0.5
150
0.5
1.0
He+
0-1.5 a.u.
100
0.0
e
tr m om =
50
-0.5
0
250 tr m om =
0.5
He+
200 1.5-3 a.u.
150
0.0
100
50
-0.5
0
200 tr m om =
0.5
counts
v ey /v p
150 3-5 a.u.
0.0
-0.5
100
50
0
300 tr m om =
0.5
5-10 a.u.
200
0.0
100
-0.5
0
0.5
100
tr m om =
10-15 a.u.
0.0
50
-0.5
0.0
0.5
v ez /v p
1.0
0
-1.0 -0.5 0.0 0.5
1.0
v ey /v p
M.A.Abdallah et al., Phys.Rev.81, 3627 (1998).
Electron spectra for Transfer Ionization for He++ on He
0.0
0.5
1.0
1.5
0.0
0.5
1.0
(e) 100
(a)
0.5
1.5
0.0
-0.5
Pt < 2.0a.u.
(b)
0.5
0
(f)
200
-0.5
Pt= 2- 4a.u.
(c)
0.5
0
(g)
300
Counts
Ve, y / Vp
0.0
0.0
Pt= 4- 8a.u.
-0.5
(d)
0.5
0
(h) 200
0.0
A.F.Afaneh, R Doerner, L Schmidt, Th
-0.5
Pt= 8-16a.u.
0.0
0.5
1.0
1.5
0.0
Ve, z / Vp
0.5
1.0
0
1.5
Weber, K E Stiebing, O Jagutzki and H
Schmidt-Boecking, J. Phys. B 35 L229
(2002).
The physics
Low energy collisions:
Capture by highly charged ions
Ionization : continuum electrons
High energy collisions:
Singleelectron
electronprocesses
processes
Single
Large Z/v
Small Z/v…photons
Large Z/v
Two electron processes
Small Z/v…photons
Fixed in space molecules:
inner shells
Intense laser
Electron ejection by charged particle: large q vs small q
V~ e i q.r
Small q………. “optical limit”
Large impact parameter
Projectile delivers energy only
Sets positive charge in
Oscillation against negative charge
Large q exchange with one electron
Rest of atom is spectator
(Rutherford and Marsden)
Single photoionization recoils
80 eV Single Ionization of He
R. Doerner et al., Phys. Rev. Lett. 76, 2654 (1996).
hn
krecoil ion = -ke
Very low perturbation He single ionization:electron – recoil
momentum balance
1 GeV/u U 92+on He
Moshammer et al.,
Phys.Rev.Lett. 79, 3621 (1997).
Kinematically complete: electron spectra for
experimentally controlled q
Photons
Charged particles
q
e
e- He+
“recoil”
q
“binary”
3 keV electrons
q=1.5 a.u.
100 MeV/u C 6+
q=.88 a.u.
A.Dorn, R.Moshammer, C.D.Schroeter, et al., Phys.Rev.Lett.82,2496(1999).
M.Schulz, R.Moshammer, D.H.Madison, R.E.Olson et al., J.Phys.B 34, L305 (2001).
Is everything understood for single ionization in the low
perturbation limit?
100 MeV/u C 6+ on He
Single ionization
electron momentum
distributions
Experiment
M.Schulz et al., Nature 422, 48 (2003)
Calculation (Madison)
Conclusion: nuclear momentum
transfer not being treated
correctly.
High perturbation He single ionization:electron-recoil
momentum balance
3.6 Mev/ Se 28+
on He
Moshammer et al.,
Phys.Rev.A 56,
1351 (1997).
The physics
Low energy collisions:
Capture by highly charged ions
Ionization : continuum electrons
High energy collisions:
Large Z/v
Single electron processes
Small Z/v…photons
Large Z/v
Twoelectron
electronprocesses
processes
Two
Small Z/v…photons
Fixed in space molecules:
inner shells
Intense laser
Two electron removal: how to do it?
TS2
TS1
L.H.Andersen, H.Knudsen,
P.Hvelplund, et al., Phys.Rev.Lett.
57, 2147 (1986).
High perturbation He double ionization: electron pair –recoil
momentum balance
Double ionization:
Electron pair ejection
3.6 MeV/u Au 53+ on He
A.N.Perumal, R.Moshammer,M.Schulz and
J.Ullrich, J.Phys.B 35, 2133 (2002).
He++
q
ee
Single ionization
3.6 Mev/ Se 28+on He
Moshammer et al.,Phys.Rev.A 56, 1351 (1997).
The small perturbation case
Small Z/v or photon
TS1 collision
Shakeoff
Electron distributions:
photodouble ionization of He
E1 selections rules DA=0 implies electrons in p state
k1
k-
e k+ = k1+k2
Jacobi
k- =(k1-k2)/2
k+
J S Briggs and V
Schmidt, J.Phys.B
33, R1 (2000).
k2
Lab
e
k1,k2
E1 selection rules plus ee repulsion;
No back to back, no parallel emission
Opening angle around 120 degrees
Photodouble ionization of He
1 eV
20 eV
excess energy
k+ = k1+k2
e
Electron
momenta
k1, k2
k- = (k1-k2)/2
H. Braeuning, R. Doerner, C.L. Cocke, M.H. Prior et al., J. Phys. B30, L649 (1997).
Can we get out of the “collective motion”
region into the “single particle motion” region?
A.Knapp, M.Walter, Th. Weber, A.L.Landers, et al., .Phys.B L521 (2002).
Photodouble ionization at 529 eV photon energy
slow
Soft electrons are shaken off
fast
e
2eV
The “shaken off” electron
Harder electrons are
generated in ee collisions
30eV
Experiment Theory (CCC:Kheifets)
A.Knapp, A.Kheifets, I.Bray, Th.Weber, A.L.Landers et al., Phys.Rev.Lett.89, 033004 (2002).
Photodouble ionization of H2: the relaxation
of the dipole selection rule Walter and Briggs, PRL
85, 1630 (2000).
Node on cone where
no dipole moment of system
along polarization vector
e
H2: Node is
There but relaxed
Thorsten Weber ,Ph.D. thesis,
Univ. Frankfurt (2003) and
Th. Weber et al., in
preparation (2003) .
Helium:
Node on cone
Photodouble ionization at 529 eV photon energy
Soft electrons are shaken off
The “shaken off” electron
Experiment
Theory (Kheifets)
A.Knapp, A.Kheifets, I.Bray, Th.Weber, A.L.Landers et al., hys.Rev.Lett.89, 033004 (2002).
Shaken electron distribution from transfer ionization
300 keV protons on He:
capture one, other leaves
H. Schmidt-Böcking, V. Mergel, R. Dörner et al., Europhys. Lett., 62 , 477 (2003) .
Correlated “Shakeoff” Shi and Lin
The probability for ionization
The momentum of the shaken electron
T.Y.Shi and C.D.Lin, Phys.Rev.Lett. 89, 163202 (2002).
High velocity TI: CRYRING
fast protons on He , capture one, make He++
recoil pz
H.T. Schmidt, A. Fardi, R. Schuch, et al., Phys. Rev. Lett., 89, 163201-3 (2002)
and Henning Schmidt, private comm. 2003
Charged particle “dipole” double ionization
Photons
He++
Charged particles
q
e
k+ =k
1+k2
Jacobi
k- =(k1-k2)/2
Lab
e
k1,k2
ee
“recoil” q “binary”
“recoil”
“binary”
Electron distributions: double ionization of He
2 keV electrons
DATA
q2
Experiment
q
“recoil”
q1
CCC Kheifets
“binary”
q=0.6a.u.
q2
q1
Photodouble ionization
A. Dorn, A.Kheifets, C.D.Schroeter, B.Jajjari et al., Phys.Rev.Lett.86, 3755(2001
The physics
Low energy collisions:
Capture by highly charged ions
Ionization : continuum electrons
High energy collisions:
Large Z/v
Single electron processes
Small Z/v…photons
Large Z/v
Two electron processes
Small Z/v…photons
Fixed
Fixed in
in space
space molecules:
molecules:
inner
Innershells
shells
Intense laser
Illuminating molecules from within
University Frankfurt:
Reinhard Dörner,Horst
Schmidt-Böcking,Thorsten Weber,Alexandra Knapp, Till Jahnke,
Lothar, Schmidt, Sven Schössler, Harald Bräuning, Achim
Czasch
Kansas State University C. Lewis Cocke, Timur Osipov, Ali
Alnaser
LBNL
Michael H. Prior, Jürgen Rösch, Andre Staudte
Western Michigan U.
Allen Landers
Guest: Amine Cassimi (Ganil/Ciril)
hv + CO  CO+ (1s-1) + e-(photoelectron) (few eV)
 CO 2+ + e-(Auger) (high energy)
 C+ + O +
(10 –17 s)
(10 –14 s)
(10 –13 s)
What determines the angular distribution of
the photoelectrons?
Depends on external radiation
Polarization of incident
Radiation : p-wave
Direction of incident radiation:
(Non-dipole effects?)
Depends on molecular
orientation
e iq.r
Interference of wave
Scattered on other
center
Shape resonance in
potential well of molecule
The sigma (f-wave) resonance in CO
is the photoelectron momentum vector
as you scan the photon energy
A.Landers, in “Photonic, Electronic and Atomic Collisions”,
ed. J.Burdoerger et al., p. 149 (Rinton, Princeton, 2002).
Steps of process and energetics
C 2H 2+
Photoelectron
hn = 309 eV
Auger
C2H2++
D.Duflot et al.,
J.Chem.Phys.10
2,1(1995).
KER
Vinylidene
channel
10
C 2H 2
20
KER spectrum
T.Osipov,KSU
Auger electron angular distributions in CO
Molecule does
NOT remember
how the hole was
made
But for some
channels the
distribution is
very sharp,
even
Headlightlike!
Th. Weber, M.Wedkenbrock, M.Balser, L.Schmidt,
O.Jagutzki et al., Phys.Rev.Lett. 90, 153003 (2003).
Is there an f-wave resonance in C2H2?
B.Kempgens et al., PRL 79, 35 (1997).
The f-wave enhancement in C2H4
Osipov, KSU, 2003
Comparison of C2H2 and C2H4
Recoil momentum spectra of near symmetric breakup for mass 24 or 26
e
Acetylene/Vinylidene
Can the angular distributions tell about the
fragmentation dynamics?
EXPT
Th.Weber et al., JPB 34, 3669 (2001).
THEORY
R.Diez Muino, D.Rolles,
F.J.Garcia de Abajo, F.Starrost,
W.Schattke, C.S.Fadley and
M.A.Van Hove, J.Electron
Spec.Relat.Phenom.99,114(2001
).
Usephotoelectrons
fragments to align
molecule,
look
at
Use
to align
molecule,
look
photoelectron
distributions
at fragmentation
dynamics
Photoemission
C2H2+
10-17 sec
Auger
C2H2++
10-14 sec
Fast?
Slow?
CH2+
C+
Lose molecule-photoelectron angle
CH+
CH+
Keep molecule-photoelectron angle
Photoelectrons for A and V
Rotation angle measured: 20 degrees
Rotation required by mass
rearrangement: 21.6 degrees
Conclusion: Data is consistent with
instantaneous rearrangement.
What is the longest time it could take ?
If additional 10 degrees,
L=2 from Auger decay, calculate
omega(rotational) times rearrangement
time 10 degrees, get
Rearrangement time shorter than 60 fs.
Calculated vibrational period for
bending mode 10 fs.
The physics
Low energy collisions:
Capture by highly charged ions
Ionization : continuum electrons
High energy collisions:
Large Z/v
Single electron processes
Small Z/v…photons
Large Z/v
Two electron processes
Small Z/v…photons
Fixed in space molecules:
inner shells
Intense
Intenselaser
laser
The Knee
B.Walker,B. Sheehy, L.F. DiMauro,
P.Agontino, K.J.Schafer and K.C.Kulander,
Phys.Rev.Lett.73,1227(1994).
Sequential
TS2
Non-sequential
TS1
Sequential ionization
TS2 - like
Non-sequential
TS1, Shakeoff
Momentum spectra for He and Ne ions
Ne
He
2.9 1014 W/cm2
e
3.8 1014 W/cm2
6.6 1014 W/cm2
Th. Weber, M. Weckenbrock, A. Staudte, L. Spielberger,
O. Jagutzki, V. Mergel, F. Afaneh, G. Urbasch, M. Vollmer,
H. Giessen, and R. Dörner, Phys.Rev.Lett. 84, 443 (2000).
R. Moshammer, B. Feuerstein, W. Schmitt, A. Dorn,
C. D. Schröter, and J. Ullrich ,H. Rottke, C. Trump,
M. Wittmann, G. Korn, K. Hoffmann, and W.
Sandner, Phys.Rev.Lett. 84, 447 (2000).
Sequential ionization
Non-sequential
Rescattering
Transition from NS to sequential for Ar
Th.Weber, M.Weckenbrock,
A.Staudte, L.Spielberger,
O.Jagutzki, V.Mergel, F.Afaneh,
G.Urbasch, M.Vollmer,
H.Giessen and R.Dörner,
Below the knee:
NS
J.Phys.B 33, L127 (2000).
Increasing laser intensity
Above the knee:
SI
Ar 2+ p1 vs p2 along polarization vector
Th. Weber, H. Giessen, M. Weckenbrock, G.
Urbasch, A. Staudte, L. Spielberger, O.
Jagutzki, V. Mergel, M. Vollmer and R.
Dörner , Nature 405, 658 (2000).
p2
e
p2
p1
p1
Off diagonal Ar 2+ momentum spectrum
B.Feuerstein, R.Moshammer, D.Fischer, A.Dorn, C.D.Schröter,
J.Deipenwisch, R.R.Crespo Lopez-Urrutia, C.Höhr, P.Neumayer,
J.Ullrich, H.Rottke, C.Trump, M.Wittmann, G.Korn and
W.Sandner, Phys.Rev.Lett. 87, 043003 (2001).
excitation
kinematics
classically
allowed
Comparison of Ar and Ne p1 vs.p2 plot
Ne
Ar
Excitation
plus laser
ionization
Classically
allowed
rescattering
ionization
R.Moshammer, J.Ullrich, B.Feuerstein, et
al., Optics Express 8, 358 (2001).
B.Feuerstein, R.Moshammer, D.Fischer, et
al., Physs.Rev.Lett. 87, 043003 (2001).
Ne double ionization electron energy spectra
R.Moshammer, J.Ullrich, B.Feuerstein, B.Fischer,
A.Dorn, C.D.Schröter, J.R.Crespo Lopez-Urrutia,
C.Höhr, H.Rottke, C.Trump, M.Wittmann, G.Korn
K.Hoffmann and W.Sandner, J.Phys.B 36, L113
(2003).
. R.Moshammer, B.Feuerstein, D.Fischer, A.Dorn,
C.d.Schroeter, J.Deipenwisch, J.R.Crespo Lopez-Urrutia, C.
Hoehr, P.Neumayer and J.Ullrich, Optics Express 8, 358
(2001).
Ne single ionization : dip in the middle
semiclassical model
(with rescattering)
J. Chen, C. Nam
PRA (2002) 053415
I = 0.7.1015 W/cm2
8000
counts
6000
4000
2000
0
-3
-2
-1
0
1
2
pion || [a.u]
R.Moshammer, J.Ullrich, B.feuerstein, D.Fischer,
A.Dorn, C.D.Schroeter, J.R.Crespo Lopez-Urrutia,
C.Hoehr, H.Rottke, C.Trump, M.Wittmann, G.Korn and
W.Sandner, to be published.
3
. R.Moshammer, B.Feuerstein, D.Fischer,
A.Dorn, C.d.Schroeter, J.Deipenwisch,
J.R.Crespo Lopez-Urrutia, C. Hoehr,
P.Neumayer and J.Ullrich, Optics Express 8,
358 (2001).
The physics
Low energy collisions:
Capture by highly charged ions
Ionization : continuum electrons
High energy collisions:
Large Z/v
Single electron processes
Small Z/v…photons
Large Z/v
Two electron processes
Small Z/v…photons
Fixed in space molecules:
inner shells
Intense
Intenselaser
laser on D2
Time of flight spectrum for laser on D2
Polarization along time direction
8 x 1014 W/cm2
Dt=100 fs
d+
counts
Energy in eV of d+
time of flight [ns]
D2+
What is all this structure?
Frazinski et al, PRL 83, 3625
Bond softening : dissociation
Zavriev et al., PRA , 1992.
This is what it is……….
8 x 1014 W/cm2
Dt=100 fs
Bond softening and ATI
d+
counts
Energy in eV of d+
CREI double ionization
Rescattering
time of flight [ns]
D2+
Evidence for rescattering double ionization in D2
Energy release of d+ pairs versus
Net momentum of system
Linear polarization
Circular polarization
The rescattering component
d+ sum energy spectra from
Laser + D2 > d+ + d+ + 2e
Difference
RES
CE = Coulomb explosion via CREI
RES = rescattering CE
0
20
Energy (eV)
Circular
Linear
RES
CE
0
20
Energy (eV)
0
20
Energy (eV)
The schematic
Niikura et al., Nature
417,917(2002)
The model and the clock
Alnaser et al.
CREI
Electrons return at 2/3 of
period plus integral number
of periods of 2.6 fs
Tong and Lin
How does the laser pulse compare to the pulse a passing
charged particle makes?
Comparison of field from laser pulse with that for a passing Xe 26+ ion
Field from 25+ ion at v=.05 with b=7 a.u.
14
2
Field from 8 x 10 W/cm , 8 fs pulse
0.6
Electric Field (a.u.)
Over barrier to make..
H2
0.4
0.2
H2
++
+
0.0
-0.2
-0.4
-500
0
Time (a.u.)
500
Summary
• Recoil momentum spectroscopy is widely applicable
• Collisions and pulses have much in common
CREDITS
The workers
Apologies to the theorists..
J.Briggs, J.Feagin, A.Kheifets,
R.E.Olson, C.D.Lin, ….
Univ. Missouri at Rolla
Ryan Kinney
Natasha
Maydanyuk
Ahmad
Hasan
Michael
Schulz
Kansas State Univ.
M.Zamkov C.Wang M.Benis S.Voss L.Cocke A.Alnaser
T.Osipov
B.Shan C.Maharjan
Univ. Frankfurt
A. Staudte, M. Trummel, T. Jahnke, M. Weckenbrock, Th. Weber, M. Hattaß, R. Grisenti, M. Schöffler, M. Balser, M. Odenweller, A.
Gumberidze, L. Schmidt
J. Nickles, Th. Jalowi, M. Kaesz, R. Dörner, A. Knapp, C. Wimmer, J. Titze, H. Schmidt-Böcking
MPI Heidelberg
Artem Rudenko, Vitor Bastos de Jesus, Robert Moshammer,
Daniel Fischer, Conny Höhr, Joachim Ullrich,
Christina Dimopoulou, Alexander Dorn, Bernold Feuerstein
CRYRING
Afshin
Fardi
Jens
Henning
Jensen
Zettergren
Henning
Henrik
Schmidt
Cederquist
Peter
Reinhed
Thorsten Weber, Ph.D.
R.Dörner, Boss
Part of the ALS Bunch
Osipov, Hertlein, Jahnke, Schriel, Cole, whole Dörner family, Prior, Benis
The End
The N2 movie
The f-wave enhancement in C2H4
Ovipov, KSU
2003
Niikura et al., Nature 417,917(2002)