SUPPORTING ONLINE MATERIAL FOR
The Genesis Solar Wind Concentrator:
Flight and Post-Flight Conditions and Modeling of Instrumental
Fractionation
By R.C. Wiens et al.
Operation Times
Operation times at the L1 Lagrangian point for the Genesis Solar Wind
Concentrator are given in Table S1. Overall the instrument operated over 112
intervals. The table gives the start and stop dates of each interval, giving the
fraction of the day to three decimals (1.4 minutes), and gives the duration of the
interval it was powered on as well as the duration between operation times. The
station keeping maneuvers initially took a large fraction of a day, but later were
accomplished in about eight hours. While there are many outages due to crossing
the high-speed wind threshold (> 800 km/s for most of the mission), most of their
durations are less than twenty minutes. Activity associated with the October,
2003, (DOY295) solar storm, with wind speeds > 1850 km/s (Skoug et al. 2004),
resulted in temporary malfunction of the spacecraft’s star tracker and the
spacecraft placed itself in safe mode prior to the onset of high-speed wind. The
Concentrator was off for a total of 12.4 days. Another outage of 6.3 days occurred
on 2004 DOY28 when the maximum operable H rejection grid voltage dropped in
response to hot spacecraft temperatures at perihelion. It was decided to lower the
solar wind speed threshold from 800 km/s to 600 km/s to limit the amount of
proton radiation to the target, as the principal occurrences for protons passing the
H rejection grid were during high speed flows. Thereafter the maximum
operational solar wind speed remained 600 km/s.
Solar Wind Angular Distributions
The Genesis spacecraft was pointed an average of 4.5 ahead of the Sun in order
to compensate for the spacecraft’s forward motion which resulted in an apparent
slightly forward velocity vector to the solar wind. Automated daily stationkeeping maneuvers kept the spacecraft within 0.5 of this average pointing
direction, as shown in Fig. S1. The resulting angle between the spacecraft spin
axis and the instantaneous solar wind flow is shown in the bottom half of the
figure.
Table S2 provides total fluences for each Genesis Ion Monitor (GIM) detector
over the course of the Concentrator operation period. The ratios of the fluences,
along with the orientation of each GIM channel, were used to determine the
angular distribution of the solar wind over the course of the Concentrator
operation period for each velocity bin.
H Rejection Grid Voltages
Fig. 5 in the main text shows the maximum H rejection grid potentials over the
course of the mission. The data from which the figure was produced is provided in
Table S3.
Backscatter Modeling
As described in the main text, backscattering was modeled as a function of angle
and energy using SRIM. The results were fit in three dimensions using Eq. 1. The
coefficients are given in Table S4.
Relationship Between Velocity and Distribution on the Target
As the solar wind velocity changes, the focus pattern on the target also changes.
This is because at higher velocity the acceleration grid does a poorer job of
straightening the ion trajectories, resulting in a greater fraction of ions missing the
target at high velocities and an overall flatter spread for the ions that do hit the
target. For oxygen the fraction hitting the target, of those ions that traverse all of
the grids, starts near 82% for 350 km/s ions and drops progressively through 77%,
68%, and 63% for the next several velocity bins. The fraction rises slightly, to
65%, at 750 km/s because of the slightly better focusing properties for ions
reflecting closer to the mirror electrode. The relative contributions of each
velocity bin to each radial annular strip are given in Table S5 for oxygen ions. The
pattern is remarkably the same for all elements up through Mg, and then for Si, S,
and Ar the 750 km/s fraction drops to zero in all annular bins as the atomic mass
increases.
Complete Results for Neon
Tables S6-S8 presents the complete modeling results for all three isotopes of
neon, along with the statistical uncertainties of each velocity and radial bin. Using
this one can see that the velocity-averaged results are consistent with massdependent fractionation. The uncertainties are mostly representative of the results
for all of the different elements.
Table S1. Operation intervals for the Genesis Solar Wind Concentrator.
Start
Day
2001
339.972
2001
340.920
unavailable
2001
341.913
2001
347.847
2002
9.776
2002
17.627
2002
22.962
2002
31.889
2002
42.847
2002
80.097
2002
86.866
2002
86.922
2002
88.826
2002
93.931
2002
95.910
2002
114.963
2002
143.104
2002
143.760
2002
144.087
2002
144.177
2002
144.264
2002
144.382
2002
144.868
2002
145.087
2002
145.142
2002
145.233
2002
168.897
2002
175.726
2002
200.910
2002
201.031
2002
201.351
2002
201.385
2002
201.490
2002
201.556
2002
205.983
2002
268.941
2002
282.915
2002
308.987
2002
345.258
2002
352.635
2003
28.971
2003
38.069
2003
79.307
2003
94.772
2003
106.942
2003
129.535
2003
150.799
2003
154.139
2003
154.774
2003
154.871
2003
155.614
2003
159.470
2003
162.992
unavailable
2003
187.909
2003
198.910
2003
211.970
2003
212.473
2003
212.647
2003
212.997
2003
213.031
2003
213.488
2003
213.634
2003
267.949
2003
307.904
2003
310.868
2003
324.040
2003
344.778
2003
344.926
2003
345.001
End
2001
2001
Day
340.804
341.901
Duration
days
0.83
0.98
Time
Off
0.12
0.01
Reason Off
New Rej Grid Voltage
Monitor data
2001
2002
2002
2002
2002
2002
2002
2002
2002
2002
2002
2002
2002
2002
2002
2002
2002
2002
2002
2002
2002
2002
2002
2002
2002
2002
2002
2002
2002
2002
2002
2002
2002
2002
2002
2002
2002
2003
2003
2003
2003
2003
2003
2003
2003
2003
2003
2003
2003
2003
2003
346.601
9.771
16.628
22.721
31.840
42.797
79.719
86.837
86.872
88.813
93.828
95.899
107.817
142.705
143.444
143.885
144.163
144.253
144.365
144.406
144.889
145.130
145.188
168.839
175.703
200.708
200.958
201.125
201.361
201.420
201.517
205.622
268.642
282.835
308.983
344.972
352.630
28.882
37.507
79.298
94.708
106.632
129.223
150.774
154.093
154.770
154.792
155.599
159.467
162.674
187.872
4.69
26.92
6.85
5.09
8.88
10.91
36.87
6.74
0.01
1.89
5.00
1.97
11.91
27.74
0.34
0.13
0.08
0.08
0.10
0.02
0.02
0.04
0.05
23.61
6.81
24.98
0.05
0.09
0.01
0.03
0.03
4.07
62.66
13.89
26.07
35.99
7.37
41.25
8.54
41.23
15.40
11.86
22.28
21.24
3.29
0.63
0.02
0.73
3.85
3.20
24.88
1.25
0.01
1.00
0.24
0.05
0.05
0.38
0.03
0.05
0.01
0.10
0.01
7.15
0.40
0.32
0.20
0.01
0.01
0.02
0.46
0.20
0.01
0.05
0.06
0.02
0.20
0.07
0.23
0.02
0.07
0.04
0.36
0.30
0.08
0.00
0.29
0.00
0.09
0.56
0.01
0.06
0.31
0.31
0.03
0.05
0.00
0.08
0.01
0.00
0.32
0.04
SKM-1A
New Mach # Table
SKM-1B
Rej Grid Test
New Rej Grid Voltage
WIND upload
SKM-1C
Rej Grid Test
Rej Grid Test
Upload Rej. Grid Patch
Rej Grid Test
New Rej Grid Voltage
Conc Safed
SKM-2A
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Rej Grid Test
Upload Rej Reset Patch
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
SKM-2B
SKM-2C
Rej Grid Test
??
SKM-3A
Lower max rej grid V
Rej Grid Test
SKM-3B
Hi-Speed Wind
Rej Grid Test
SKM-3C
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
SKM-4A
Monitor data
2003
2003
2003
2003
2003
2003
2003
2003
2003
2003
2003
2003
2003
2003
2003
2003
198.833
211.649
212.456
212.624
212.976
213.013
213.448
213.624
267.633
295.510
310.802
323.737
344.774
344.894
344.936
345.062
10.92
12.74
0.49
0.15
0.33
0.02
0.42
0.14
54.00
27.56
2.90
12.87
20.73
0.12
0.01
0.06
0.08
0.32
0.02
0.02
0.02
0.02
0.04
0.01
0.32
12.39
0.07
0.30
0.00
0.03
0.06
0.01
Rej Grid Test
SKM-4B
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
SKM-4C
Conc Safed; S/C Safed
Rej Grid Test
SKM-5A
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
2003
2003
2003
2003
2003
2003
2003
2003
2003
2003
2003
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
345.073
345.207
345.240
345.337
345.406
345.476
345.808
345.875
347.260
347.867
347.979
15.009
34.868
46.986
47.182
47.477
47.569
48.124
54.988
60.194
61.115
61.224
62.856
63.342
63.728
64.113
70.981
71.818
71.846
71.994
72.031
72.088
72.348
72.395
87.524
87.576
89.247
89.431
89.463
89.613
89.656
89.797
89.840
2003
2003
2003
2003
2003
2003
2003
2003
2003
2003
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
2004
345.177
345.215
345.326
345.389
345.458
345.799
345.842
347.255
347.860
347.906
14.688
28.547
46.970
47.168
47.474
47.566
47.703
54.978
60.103
60.205
61.125
61.234
62.877
63.354
64.099
69.955
70.988
71.827
71.859
72.021
72.085
72.108
72.362
87.515
87.557
87.726
89.420
89.444
89.569
89.639
89.709
89.825
92.672
0.10
0.01
0.09
0.05
0.05
0.32
0.03
1.38
0.60
0.04
31.71
13.54
12.10
0.18
0.29
0.09
0.13
6.85
5.12
0.01
0.01
0.01
0.02
0.01
0.37
5.84
0.01
0.01
0.01
0.03
0.05
0.02
0.01
15.12
0.03
0.15
0.17
0.01
0.11
0.03
0.05
0.03
2.83
0.03
0.02
0.01
0.02
0.02
0.01
0.03
0.00
0.01
0.07
0.32
6.32
0.02
0.01
0.00
0.00
0.42
0.01
0.09
0.91
0.10
1.62
0.47
0.37
0.01
1.03
0.83
0.02
0.13
0.01
0.00
0.24
0.03
0.01
0.02
1.52
0.01
0.02
0.04
0.02
0.09
0.02
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
SKM-5B
Conc Safed
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Max v chg to 600 km/s
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
Hi-Speed Wind
End of Collection
Rej Grid = H rejection grid; SKM = station keeping maneuver; Conc = Concentrator; S/C = spacecraft; Max v
chg = maximum voltage change
Table S2. Total fluences, in arbitrary units, for each Genesis Ion Monitor channel
electron multiplier (CEM) per 100 km/s velocity bin, with median angle from the spin
axis for each detector.
v (km/s)
CEM 1
CEM 2
300-400
7.03e11 9.21e12 1.08e13 5.19e12 2.05e12 4.61e11 1.19e11 2.89e10
400-500
6.23e11 8.73e12 1.12e13 5.73e12 2.46e12 6.51e11 2.03e11 6.14e10
500-600
3.50e11 5.06e12 6.58e12 3.34e12 1.40e12 4.11e11 1.51e11 5.56e10
600-700
1.88e11 2.76e12 3.83e12 1.87e12 6.98e11 1.78e11 5.68e10 1.90e10
700-800
8.15e10 1.29e12 1.85e12 8.21e11 2.61e11 5.95e10 1.74e10 5.29e09
Angle (deg)
0.28
2.78
CEM 3
5.78
CEM 4
8.77
CEM 5
11.77
CEM 6
14.77
CEM 7
17.77
CEM 8
20.77
Table S3. Maximum H rejection grid voltages allowed by software.
Start
Day
Max
Volts
2001
339.965
1300
2001
341.913
1500
2002
31.889
1600
2002
88.826
1880
2002
95.908
2060
2002
114.963
1980
2002
143.104
1880
2002
175.726
2060
2002
352.635
1980
2003
211.970
2120
2003
307.904
1980
2004
34.868
1650
2004
89.840
0
Table S4. Backscattering fit coefficients for various ions using Eq. 1. Unless otherwise noted, the substrate is SiC. Subscripts denote the power of the terms in the polynomial.
3He
4He
6Li
7Li
x0
4.97E0
4.98E0
4.50E0
3.09E0
x1
1.30E-2
1.17E-2
7.46E-3
x2
1.83E-3
1.83E-3
1.97E-3
x3
9.80E-7
1.07E-6
9.61E-7
x4
1.93E-6
1.94E-6
1.83E-6
y0
3.01E0
3.03E0
y1
1.13E-3
y2
9.69E-7
y3
y4
residual
12C
in Si
13C
in Si
14N
15N
16O
18O
20Ne
22Ne
24Mg
26Mg
2.20E-1 1.15E-1
36Ar
38Ar
4.46E0
3.32E0
9.66E-1
9.27E-1
1.26E0
5.90E-1
5.74E-1
3.80E-1
5.00E-2
5.46E-2
6.79E-4
0.00E0
-6.27E-4
-6.79E-3
-6.55E-3
-1.26E-2
-9.99E-3
-1.48E-2
-1.50E-2 -2.39E-2 -2.04E-2 -4.70E-2
-4.65E-2
5.85E-3
2.17E-3
5.96E-3
5.09E-3
5.07E-3
4.94E-3
4.93E-3
5.12E-3
4.96E-3
5.15E-3
5.13E-3
-1.53E-4
0.00E0
-1.57E-4
-1.68E-4
-1.68E-4
-1.68E-4
-1.68E-4
-1.68E-4
-1.70E-4 -1.71E-4 -1.34E-4 -1.82E-4
-1.83E-4
3.34E-6
1.90E-6
3.42E-6
3.14E-6
3.14E-6
3.13E-6
3.13E-6
3.13E-6
3.14E-6
3.16E-6 2.82E-6
2.62E-6
2.60E-6
2.50E0
1.55E0
2.19E0
1.52E0
3.45E-1
3.53E-1
5.26E-1
1.96E-1
1.51E-1
1.03E-1
4.21E-2 1.17E-2
1.24E-3
1.11E-3
1.24E-3
6.22E-3
2.84E-2
4.85E-3
2.24E-2
1.92E-2
1.88E-2
1.74E-2
1.60E-2
1.74E-2
1.30E-2
5.08E-3 1.37E-3
2.33E-5
2.13E-5
9.61E-7
7.33E-7
5.95E-4
6.93E-7
8.93E-4
4.35E-4
4.42E-4
3.08E-4
4.15E-4
4.36E-4
4.74E-4
4.62E-4 4.05E-4
1.65E-5
1.71E-5
6.49E-5
6.45E-5
5.34E-5
1.25E-6
4.52E-5
-1.20E-5
-1.44E-5
-1.43E-5
-1.43E-5
-1.41E-5
-1.61E-5
-1.65E-5 -1.75E-5 -1.67E-5 -3.75E-6
-3.79E-6
2.5E-7
2.45E-7
2.48E-5
8.51E-7
2.40E-7
8.53E-7
7.39E-7
7.39E-7
7.16E-7
7.13E-7
7.08E-7
7.00E-7
3.18E-7
3.15E-7
8.39
7.07
9.85
9.77
9.76
7.84
5.76
4.72
8.13
7.33
4.95
4.41
3.92
3.49
4.72E-3 3.45E-3
6.77E-7 6.93E-7
6.13
6.94
Table S5. Relative contributions of each velocity bin to each radial strip.
R (mm)
350 km/s
450 km/s
550 km/s
650 km/s
750 km/s
Total
0-5
0.28
0.33
0.19
0.12
0.08
1.00
5-10
0.27
0.33
0.20
0.13
0.08
1.00
10-15
0.24
0.33
0.21
0.14
0.08
1.00
15-20
0.20
0.34
0.22
0.15
0.09
1.00
20-25
0.15
0.33
0.24
0.18
0.10
1.00
25-30
0.11
0.32
0.26
0.20
0.11
1.00
Table S6. Modeling results for all three isotopes of neon.
Radial Bin
(mm)
Ne-20 IONS ON TARGET
368 km/s
475 km/s
580 km/s
Ne-21 IONS ON TARGET
686 km/s
790 km/s
368 km/s
475 km/s
580 km/s
Ne-22 IONS ON TARGET
686 km/s
790 km/s
368 km/s
475 km/s
580 km/s
686 km/s
790 km/s
0-5
158206
112814
67247
39247
53721
160866
114187
91687
59549
43867
160968
116355
70224
40364
43532
5-10
413887
309078
185058
106679
143976
415791
310617
250763
161841
114656
416883
312071
190321
109864
114189
10-15
461069
388455
243072
142669
185989
458405
388018
324069
216138
148071
456980
387526
244741
144969
146109
15-20
328714
337466
227360
141360
173627
324848
335907
299971
212709
137790
322542
333311
224503
142031
134504
20-25
176185
231390
170150
112648
132892
176293
229721
226095
168309
104875
175677
228804
168645
111701
103663
25-30
84108
140482
115341
78081
90237
84664
139236
153226
116400
71696
86523
138560
114100
77333
70239
Total on tgt*
1632790
1541315
1027692
633748
795430
1631710
1539055
1371285
954310
632609
1630722
1538054
1031925
639006
623564
Total flown
2.00E+06
2.00E+06
1.50E+06
1.00E+06
1.25E+06
2.00E+06
2.00E+06
2.00E+06
1.50E+06
1.00E+06
2.00E+06
2.00E+06
1.50E+06
1.00E+06
1.00E+06
*includes a bin for 30-31 mm, out to the edge of the target assembly; the statistics of that bin by itself are insignificant
Table S7. Calculated instrumental fractionation for neon isotopes, from results in Table S6
Radial Bin
(mm)
0-5
5-10
10-15
15-20
20-25
25-30
Total
368
km/s
16.81
4.60
-5.78
-11.76
0.61
6.61
-0.66
d-21Ne (permil)
d-22Ne (permil)
475
580
686
790
Velocity- 368
475
580
686
790
Velocitykm/s
km/s
km/s
km/s
Averaged km/s
km/s
km/s
km/s
km/s
Averaged
12.17
22.58
11.53
20.71
16.07
17.46
31.39
44.27
28.46
12.92
28.20
4.98
16.29
11.39
-4.56
7.17
7.24
9.68
28.44
29.86
-8.61
13.84
-1.12
-0.08
9.97
-4.84
-0.82
-8.87
-2.39
6.87
16.12
-18.03
-0.78
-4.62
-10.48
3.16
-8.00
-6.44
-18.78
-12.31
-12.57
4.75
-31.66
-12.70
-7.21
-3.40
-3.92
-13.53
-5.13
-2.88
-11.18
-8.85
-8.41
-24.93
-10.19
-8.87
-3.65
-6.16
-6.84
-4.96
28.71
-13.68
-10.76
-9.58
-27.02
-8.59
-1.47
0.75
3.88
-5.87
-0.39
-1.27
-2.12
4.12
8.30
-20.08
-0.57
Table S8. Statistical uncertainties on the entries in Table S7.
Radial Bin
(mm)
0-5
5-10
10-15
15-20
20-25
25-30
Total
d-21Ne Uncertainty (permil)
d-22Ne Uncertainty (permil)
368
475
580
686
790
Velocity- 368
475
580
686
790
Velocitykm/s
km/s
km/s
km/s
km/s
Averaged km/s
km/s
km/s
km/s
km/s
Averaged
3.60
4.25
5.19
6.58
6.57
2.23
3.60
4.31
5.63
7.29
6.53
2.31
2.21
2.55
3.11
3.99
3.94
1.34
2.21
2.56
3.36
4.43
3.93
1.39
2.07
2.27
2.68
3.45
3.47
1.19
2.07
2.26
2.88
3.79
3.43
1.22
2.44
2.43
2.75
3.44
3.58
1.28
2.43
2.41
2.94
3.77
3.52
1.30
3.37
2.92
3.20
3.83
4.07
1.57
3.36
2.92
3.41
4.19
4.04
1.59
4.90
3.75
3.88
4.60
4.97
2.05
4.98
3.73
4.13
5.02
4.90
2.10
1.11
1.14
1.31
1.63
1.67
0.60
1.11
1.14
1.40
1.79
1.66
0.61