Demonstration of MOTRIMS Probing Capability
description
Transcript of Demonstration of MOTRIMS Probing Capability
Demonstration of MOTRIMS Probing Capability
Hai Nguyen, Richard Brédy, Howard Camp, Takaaki Awata, Kyle Wilson,
Brett DePaola.
OUTLINE
Motivation
Experimental Setup
Review of earlier results
New Results
MOTIVATION
Collisions with excited target
Cross-section measurements provide rigorous test for TC-AOCC.
Optimizing MOTRIMS capabilities.
EXPERIMENTAL SETUP
PREVIOUS RESULTS7 keV Na+ + Rb (5s, 5p)
-5
-4
-3
-2
-1
0
4d 2D5/2
, 4d2D3/2
4f 2F7/2
, 4f2F5/2
5s 2S1/2
4p 2P1/2
, 4p 2P3/2
23Na
4s 2S1/2
3d 2D5/2
, 3d2D3/2
3p 2P1/2
, 3p 2P3/2
3s 2S1/2
12f
4d 2D3/2,5/2
5p 2P3/2
5s 2S1/2
87Rb
Pote
ntia
l Ene
rgy
(eV)
-3 -2 -1 0 1 2 30
2000
4000
6000
8000
10000
12000
14000
16000
4p*
3d*
4d*
5s*
3d
4s*
3p
3p*
3s
Coun
ts
Q value (eV)
PREVIOUS RESULTS7 keV Na+ + Rb (5s, 5p)
-3 -2 -1 0 1 2 30
1000
2000
3000
4000
5000-3 -2 -1 0 1 2 3
0
5000
10000
15000
5s-3p
5s-3sCo
un
ts
Q value (eV)
Off
y0 786 ±0xc1 0.96112 ±0.00163w1 0.21422 ±0.00328A1 1137.9999 ±15.01743xc2 0.4429 ±0.00137w2 0.21877 ±0.00278A2 1390.17651 ±15.17554
5p-3p5s-3s
5s-3p
5p-3d5p-4p
5p-4s
Co
un
ts
Tot
-3 -2 -1 0 1 2 30
5
10
15
20
Q Value (eV)
TAC
Tim
e (
s)
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
PREVIOUS RESULTS7 keV Na+ + Rb (5s, 5p)
offonp
onss
offs TnnA )(
ons
onp
onp
ons
s
p
A
A
n
n
ononss
ons TnA
off islaser when Time T
on islaser when Time T
off islaser when s from capture of Amplitude A
on islaser when s from capture of Amplitude A
on islaser when state iin atoms ofnumber n
off
on
offs
ons
th
i
on
off
offs
ons
ons
onp
onp
T
T
A
A
nn
nf 1
ononpp
onp TnA
PREVIOUS RESULTS7 keV Na+ + Rb (5s, 5p)
0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.400
1
2
3
4
5
P /
S
Excited State Fraction
P /
S
Average P /
S
-3 -2 -1 0 1 2 30
2000
4000
6000
8000
10000
12000
14000
16000
4p*
3d*
4d*
5s*
3d
4s*
3p
3p*
3s
Coun
ts
Q value (eV)
PREVIOUS RESULTSCompared to calculation
1 2 3 4 5 6 7 81
10
100
Collision Energy (keV)
1 2 3 4 5 6 7 81
10
100
Collision Energy (keV)
ss
ps
35
35
sp
pp
45
35
PREVIOUS RESULTS7 keV Na+ + Rb (5s, 5p)
-3.0 -2.5 -2.0 -1.5 -1.0 -0.5 0.0 0.5 1.0 1.5 2.0 2.5 3.00.0000
0.0005
0.0010
0.0015
0.0020 Matrix1
5s-3d
7 keV Na++Rb(5s),Rb(5p) Na*+Rb+
5s-3p
5p-4d
5p-4s
5p-3p
5s-3s
2.000
3.431
5.886
10.10
17.32
29.72
50.99
87.48
150.1
257.5
441.7
757.8
1300
Q value (eV)
Sca
tterin
g A
ngle
(ra
d)
PREVIOUS RESULTSCompared to calculation
0.0 0.5 1.0 1.5 2.00
2
4
6
8
10
12
14
sin x
DC
S (1
0-1
1cm
2 )
0.0 0.5 1.0 1.5 2.00
2
4
6
85P - 3P
E = 2 keVE = 5 keVE = 7 keV
E (mrad)
Expt
. DC
S (1
0-1
1cm
2 )
0 1 2 3 4 50
2
4
6
8
10
12
sin x
DC
S (1
0-1
3cm
2 )
E (mrad)
0 1 2 3 4 50
2
4
6
8
10
E = 5 keV
E = 2 keV
E = 7 keV
5S - 3P
Expt
. DC
S (1
0-1
3cm
2 )
(keV mrad) (keV mrad)
5p-3p 5s-3p
Other Collision Systems: Difficulty
-6
-5
-4
-3
-2
-1
012f
4d 2D3/2,5/2
5p 2P3/2
5s 2S1/2
3p 2P1/2
, 3p 2P3/2
3d 2D5/2
, 3d2D3/2
3s 2S1/2
2p 2P1/2
, 2p 2P3/2
2s 2S1/2
7Li87Rb
Poten
tial E
nerg
y (e
V)
-5
-4
-3
-2
-1
012f
4d 2D3/2,5/2
5p 2P3/2
5s 2S1/2
12f
87Rb
4d 2D3/2,5/2
5p 2P3/2
5s 2S1/2
Pote
ntia
l Ene
rgy
(eV)
CURRENT RESULTS7 keV Li+ + Rb (5s, 5p)
-3 -2 -1 0 1 2 30
5
10
15
20
Q Value (eV)
Tim
e (s
)
1.000
1.886
3.557
6.707
12.65
23.85
44.99
84.84
160.0
-3 -2 -1 0 1 2 30
3000
6000
9000
5s-3s
5p-3p
5s-2p 5p-3s
5p-2p
5s-2s
Coun
ts
Q Value (eV)
total
7 keV Li+ + Rb
Multi-Projectile Source
0 1000 2000 3000 4000 5000 6000 7000
100
1000
10000
7Li+ + Rb
6Li+ + Rb
23Na+ + Rb
Cou
nts
TOF (channels)
Total TOF Spectrum
Probe (Na contaminant)
From Previous Results Na+From Na+ Contaminant
MOT excited state fraction
p
son
off
offs
onp
offs
onp
ons
onp
onp
T
T
A
A
n
n
nn
nf
7 keV Na+ Contaminant
p
son
off
offs
onp
offs
onp
sp
p
T
T
A
A
n
n
nn
nf
04.019.0 f
-3 -2 -1 0 1 2 30
50
100
150
200
250
300
5s-3p
5p-4s
5p-3p
5s-3s
Coun
ts
Q Value (eV)
Total
Na+ Contaminant in Li+ source
p
son
off
offs
onp
offs
onp
ons
onp
onp
T
T
A
A
n
n
nn
nf
From measurements of Li+ Unknown Li+
Cross Sections 7 keV Li+ + Rb
35.048.3 s
p
023.0828.025
s
ps
091.0125.035
p
pp
Waiting for TC-AOCC results
076.0172.025
s
ss
022.0658.035
p
sp
045.0217.025
p
pp
7 keV Li+ + Rb Scattering Angle Information
0 200 400 600 800 10000
1000
2000
3000
4000
5000
6000
7000
8000
Coun
ts
Scattering Angle (rad)
5p-3p, 5s-2p, 5p-3s
-3 -2 -1 0 1 2 30
500
1000
1500
2000
5s-2s
5p-2p
5p-3s5s-2p5p-3p
Q Value (eV)
Scatt
erin
g An
gle (
rad)
1.000
2.400
5.759
13.82
33.17
79.59
191.0
458.4
1100
7 keV Li+ + Rb Scattering Angle Information
0 200 400 600 800 10000
500
1000
1500
2000
2500
Coun
ts
Scattering Angle (rad)
5p-2p, 5s-2s
Grouped scattering angle information are hard to extrapolate (Rb + Rb).
Theoretical Comparison not trustworthy.
Using a weighted method to deduce individual channel scattering angle information.
Weighted Method (Rb+ + Rb)
Consider an even more extreme case: Rb+ + Rb collision system, where s-s & p-p are completely overlapped.
Because lasers are turned
on/off, we know exactly when capture from 5p not possible.
Weighted by excited state fraction we deduce [Qvs]ss & [Qvs]pp separately.
1.59-1.59 0
TA
C ti
me s
Q Value (eV)5s-5p
5p-5s
5s-5s5p-5p
0
20
5s
Weighted Method (Rb+ + Rb)
onpp
onss
ontotal NNN
onpp
onss
ontotal NNN
)1( fNT
TN off
ssoff
ononss
1.59-1.59 0
TA
C ti
me s
Q Value (eV)5s-5p
5p-5s
5s-5s5p-5p
0
20
5s
)1(
1fN
T
TN
fN off
ssoff
onontotal
onpp
)1( fNT
TN off
ssoff
ononss
7 keV Li+ + Rb Scattering Angle Information
-3 -2 -1 0 1 2 30
500
1000
1500
2000
5p-3p 5s-2s5p-2p
5p-3s5s-2p
Q Value (eV)
Scatt
erin
g An
gle(
rad)
1.000
2.306
5.318
12.26
28.28
65.23
150.4
346.9
800.0
-3 -2 -1 0 1 2 30
500
1000
1500
2000
5s-2s
5s-2p
Q Value (eV)
Scatt
erin
g An
gle(
rad)
1.000
2.080
4.325
8.996
18.71
38.91
80.92
168.3
350.0
Laser on Laser off
7 keV Li+ + Rb Scattering Angle Information
0 200 400 600 800 10000
200
400
600
800
1000
Co
unts
Scattering Angle (rad)
NssON
0 200 400 600 800 10000
500
1000
1500
2000
2500
3000
Coun
ts
Scattering Angle (rad)
NppON
DEVELOPMENTS
Double (multiple) species pellets development technique.
Diode lasers control and implementation.
Technique of analysis.
SUMMARY
Multiple species pellets along with extremely high resolution in Q-value allow us to make ‘in situ’ measurements of excited state fraction and relative cross sections.
Kinematically complete collisions study for energetically degenerate channels.
MOTRIMS is a powerful tool for ion-atom collisions.
SIMPLE OPTICS LAYOUT
TRAP
REPUMP
Sat abs
Sat abs
F=40cmAOM 80MHz Com
TRAPPING OPTICS
Blocker
F=40cm
O I/2
O I
/2
DAVLL
DAVLL
SIMPLE OPTICS LAYOUT
PBS
PBS
/2
/2
/4
/4
/4
/4
/4
/4
MirrorM
irror
Mirror
Mirror
Mir
ror
Mirror
From AOM
Projected TOF
0 20 40 60 80 100 120 1404.5x10-5
5.0x10-5
5.5x10-5
6.0x10-5
6.5x10-5
7.0x10-5
7.5x10-5
8.0x10-5
8.5x10-5
9.0x10-5
Cs133
Rb85
K39
Na23
Li6
TO
F s
Mass a.u.
2 KeV 5 KeV 7 KeV
6 8.268E-5 8.548E-5 8.623E-523 7.538E-5 8.086E-5 8.232E-539 7.087E-5 7.801E-5 7.991E-585 6.162E-5 7.216E-5 7.497E-5133 5.442E-5 6.761E-5 7.112E-5
--
Mass a.u. 2 keV s 5 keV s 7 keV s
STIRAP Application
STIRAP Application
MOTRIMS will allow us to monitor relative population.
Gain insights into non-destructive STIRAP physics.
STIRAP Sample Results
-2.0 -1.5 -1.0 -0.5 0.0 0.5 1.0 1.5 2.0
0
1000
2000
3000
7 keV Na+ + Rb(5s),Rb(5p),Rb(4d)
Na(
4d)
Na(
4p)
Na(
3d)
Na(
3p)
Na(
4s)
Na(
4p)
Na(
3d)
Na(
4s)
Na(
3p)
Na(
3s)
Capture on Rb(5s)Capture on Rb(5p)Capture on Rb(4d)
Cou
nts
Q Value (eV)
0 2 4 6 8 100.0
500.0
1000.0
1500.0
2000.0
2500.0
3000.0Laser ONLaser ON Laser OFFLaser OFF
Rb5s Rb5p Rb4d
Coun
t
Time (ms)