apr 17-22, 20061 tunable filter wavelength scan and calibration of intensity ripple y. katsukawa...
TRANSCRIPT
Apr 17-22, 20061
Tunable filter wavelength scan and calibration of intensity ripple
Y. Katsukawa (NAOJ) and SOT team
Apr 17-22, 2006 2
TF wavelength scan
Wavelength scan by the tunable filter was performed to verify spectroscopic performance and its uniformity over the field-of-view.
Two data sets– Solar spectra to check spectrum line profiles and their
uniformity– Lamp source (emitting continuum light) to check
intensity variation through the scan
Each full FOV image is divided into 8x4 sub-images, and spectrum is created in each sub-image.
0 005 0001 0051 00020
002
004
006
008
0001
Apr 17-22, 2006 3
Wavelength scan of the solar spectrum lines (1)
Mg I 5172A
Fe I 5250A
Black: Measured spectraRed: Atlas +TF ideal profiles
2.0
4.0
6.0
8.0
0.1
no
rma
lize
d in
ten
isty
0001- 005- 0 005 0001)Am(
2.0
4.0
6.0
8.0
0.1
no
rma
lize
d in
ten
isty
0001- 005- 0 005 0001)Am(
Apr 17-22, 2006 4
Wavelength scan of the solar spectrum lines (2)
Fe I 5576A
Na I 5896A
2.0
4.0
6.0
8.0
0.1
no
rma
lize
d in
ten
isty
0001- 005- 0 005 0001)Am(
2.0
4.0
6.0
8.0
0.1
no
rma
lize
d in
ten
isty
0001- 005- 0 005 0001)Am(
Black: Measured spectraRed: Atlas +TF ideal profiles
Apr 17-22, 2006 5
Wavelength scan of the solar spectrum lines (3)
Fe I 6302A
H I 6563A
2.0
4.0
6.0
8.0
0.1
no
rma
lize
d in
ten
isty
0001- 005- 0 005 0001)Am(
2.0
4.0
6.0
8.0
0.1
no
rma
lize
d in
ten
isty
0001- 005- 0 005 0001)Am(
Black: Measured spectraRed: Atlas +TF ideal profiles
Apr 17-22, 2006 6
Solar spectra by NFI
These data sets show the line profiles are roughly consistent with the atlas spectra, and roughly uniform over the FOV.
Two features can be seen in the spectra1. Periodic intensity variation, especially significant in 5250A.
2. The line profiles are slightly shallower than the atlas spectra.
In order to distinguish the solar spectrum features and intensity variation caused by the instrument, wavelength scans were carried out using a lamp source emitting continuum light.
Apr 17-22, 2006 7
Wavelength scan of a lamp source (1)
Mg I 5172A
Fe I 5250A
0.8
0.9
1.0
1.1
1.2
norm
alize
d inte
nis
ty
-1000-500 0 500 1000(mA)
0.8
0.9
1.0
1.1
1.2
norm
alize
d inte
nis
ty
-1000-500 0 500 1000(mA)
Black: Measured intensityRed: Fitting result
Apr 17-22, 2006 8
Wavelength scan of a lamp source (2)
Fe I 5576A
Na I 5896A
0.8
0.9
1.0
1.1
1.2
norm
alize
d inte
nis
ty
-1000-500 0 500 1000(mA)
0.8
0.9
1.0
1.1
1.2
norm
alize
d inte
nis
ty
-1000-500 0 500 1000(mA)
Black: Measured intensityRed: Fitting result
Apr 17-22, 2006 9
Wavelength scan of a lamp source (3)
Fe I 6302A
H I 6563A
0.8
0.9
1.0
1.1
1.2
norm
alize
d inte
nis
ty
-1000-500 0 500 1000(mA)
0.8
0.9
1.0
1.1
1.2
norm
alize
d inte
nis
ty
-1000-500 0 500 1000(mA)
Black: Measured intensityRed: Fitting result
Apr 17-22, 2006 10
Intensity ripple in TF wavelength scan
Amplitudes of the ripple are around 10 – 20 %, and are position dependent over FOV. They are also dependent on wavelengths.
Periodic variation is dominant in 5172A and 5250A. We found two periods are dominant in the ripples.
For the longer wavelengths, the ripple profiles are more complex. Many periods may be superposed.
Apr 17-22, 2006 11
Model of the intensity ripple
TF consists of 8 calcite blocks and 8 tuning elements (motors). Each calcite block has a halfwave plate in the middle of the block to make wide fields.
The tuning elements move periodically through the scan, and their periods are different from each other.
The intensity ripple can be reproduced by giving errors to retardation of the halfwave plates in the calcite blocks 3 and 6.
block# composition length (mm) normalized0 Entrance window
0 1 calcite-0a 4.4052 halfwave-0 5.0343 calcite-0b 4.4054 quaterwave-05 halfwave Motor-06 polaroid Motor-1
1 7 quaterwave-18 calcite-1a 5.2859 halfwave-1 6.040
10 calcite-1b 5.28511 polaroid
2 12 calcite-2a 7.01013 halfwave-2 8.01114 calcite-2b 7.01015 quaterwave-216 halfwave Motor-217 polaroid Motor-3
3 18 quaterwave-319 calcite-3a 55.95020 halfwave-3 63.94321 calcite-3b 55.95022 partial polaroid
4 23 calcite-4a 28.02024 halfwave-4 32.02325 calcite-4b 28.02026 quaterwave-427 halfwave Motor-428 polaroid Motor-5
5 29 quaterwave-530 calcite-5a 28.00031 halfwave-5 32.00032 calcite-5b 28.00033 partial polaroid
6 34 calcite-6a 13.97535 halfwave-6 15.97136 calcite-6b 13.97537 quaterwave-638 halfwave Motor-639 polaroid Motor-7
7 40 quaterwave-741 calcite-7a 3.46042 halfwave-7 3.95443 calcite-7b 3.46044 Ext window
292.210
halfwave-6; del=0.1, halfwave-3; del=0.05, 5250A
Apr 17-22, 2006 12
Calibration of the intensity ripple
If the intensity ripple is caused by the halfwave plates in the calcite blocks, the intensity modulation can be represented as a function of the motor positions (provided by encoders) of the tuning elements.
Calcite block Motor pos
Calcite-02*(Motor-0)+(Motor-1)
Calcite-1 (Motor-1)
Calcite-22*(Motor-2)+(Motor-3)
Calcite-3 (Motor-3)
Calcite-42*(Motor-4)+(Motor-5)
Calcite-5 (Motor-5)
Calcite-62*(Motor-6)+(Motor-7)
Calcite-7 (Motor-7)
)sin(7
00 i
iiii baII
ia
ib
: Intensity amplitude for ith calcite block (Position dependent)
: Phase of the motor position for ith calcite block (Position dependent)
i : Motor positions corresponding to ith calcite block
ai and bi are derived by fitting of the intensity profiles at each position in FOV.
Apr 17-22, 2006 13
5250A amplitude and phase distribution @ T21C
Amplitude of Period-1
0 500 1000 1500 20000
200
400
600
800
1000
0.04 0.06 0.08 0.10 0.12 0.14 0.16
Phase of Period-1
0 500 1000 1500 20000
200
400
600
800
1000
16 18 20 22
Amplitude of Period-2
0 500 1000 1500 20000
200
400
600
800
1000
0.015 0.020 0.025 0.030 0.035
Phase of Period-2
0 500 1000 1500 20000
200
400
600
800
1000
-6 -4 -2 0 2 4
Calcite-6
Calcite-3
Amplitude
Amplitude Phase
Phase
Apr 17-22, 2006 14
Amplitude of Period-1
0 500 1000 1500 20000
200
400
600
800
1000
0.04 0.06 0.08 0.10 0.12 0.14 0.16
Phase of Period-1
0 500 1000 1500 20000
200
400
600
800
1000
18 20 22 24
Amplitude of Period-2
0 500 1000 1500 20000
200
400
600
800
1000
0.015 0.020 0.025 0.030 0.035
Phase of Period-2
0 500 1000 1500 20000
200
400
600
800
1000
-4 -2 0 2 4 6
5250A amplitude and phase distribution @ T25C
Calcite-6
Calcite-3
Amplitude
Amplitude Phase
Phase
The amplitude and phase are almost the same as those at T21C.
Apr 17-22, 2006 15
Spectra after calibration of I-ripple: 5250A
Fe I 5250A
Black: After correctedRed: Atlas +TF ideal profiles
Black: Measured Red: Atlas +TF ideal profiles
0.2
0.4
0.6
0.8
1.0
norm
alize
d inte
nis
ty
-1000-500 0 500 1000(mA)
2.0
4.0
6.0
8.0
0.1
no
rma
lize
d in
ten
isty
0001- 005- 0 005 0001)Am(
Apr 17-22, 2006 16
Calcite-3: Amplitude
0 500 1000 1500 20000
200
400
600
800
1000
0.020 0.025 0.030 0.035 0.040 0.045Calcite-3: Phase
0 500 1000 1500 20000
200
400
600
800
1000
2 4 6 8 10 12
Calcite-6: Amplitude
0 500 1000 1500 20000
200
400
600
800
1000
0.02 0.04 0.06 0.08Calcite-6: Phase
0 500 1000 1500 20000
200
400
600
800
1000
20 30 40 50 60
Calcite-5: Amplitude
0 500 1000 1500 20000
200
400
600
800
1000
0.10 0.12 0.14 0.16 0.18 0.20Calcite-5: Phase
0 500 1000 1500 20000
200
400
600
800
1000
14 16 18 20 22 24 26
6302A amplitude and phase distribution
Calcite-6
Calcite-3Amplitude Phase
Amplitude Phase
Amplitude Phase
Calcite-5
Apr 17-22, 2006 17
Spectra after calibration of I-ripple: 6302A
Fe I 6302A
Black: After correctedRed: Atlas +TF ideal profiles
0.2
0.4
0.6
0.8
1.0
norm
alize
d inte
nis
ty
-1000-500 0 500 1000(mA)
2.0
4.0
6.0
8.0
0.1
no
rma
lize
d in
ten
isty
0001- 005- 0 005 0001)Am(
Black: Measured Red: Atlas +TF ideal profiles
Apr 17-22, 2006 18
Spectra after calibration of I-ripple: 5576A
Fe I 5576A
Black: After correctedRed: Atlas +TF ideal profiles
Black: Measured Red: Atlas +TF ideal profiles
0.2
0.4
0.6
0.8
1.0
norm
alize
d inte
nis
ty
-1000-500 0 500 1000(mA)
2.0
4.0
6.0
8.0
0.1
no
rma
lize
d in
ten
isty
0001- 005- 0 005 0001)Am(
Apr 17-22, 2006 19
Spectra after calibration of I-ripple: 5172A
Mg I 5172A
Black: After correctedRed: Atlas +TF ideal profiles
Black: Measured Red: Atlas +TF ideal profiles
0.2
0.4
0.6
0.8
1.0
norm
alize
d inte
nis
ty
-1000-500 0 500 1000(mA)
2.0
4.0
6.0
8.0
0.1
no
rma
lize
d in
ten
isty
0001- 005- 0 005 0001)Am(
Apr 17-22, 2006 20
Spectra after calibration of I-ripple: 5896A
Na I 5896A
Black: After correctedRed: Atlas +TF ideal profiles
Black: Measured Red: Atlas +TF ideal profiles
0.2
0.4
0.6
0.8
1.0
norm
alize
d inte
nis
ty
-1000-500 0 500 1000(mA)
2.0
4.0
6.0
8.0
0.1
no
rma
lize
d in
ten
isty
0001- 005- 0 005 0001)Am(
Apr 17-22, 2006 21
Spectra after calibration of I-ripple: 6563A
H I 6563A
Black: After correctedRed: Atlas +TF ideal profiles
Black: Measured Red: Atlas +TF ideal profiles
0.2
0.4
0.6
0.8
1.0
norm
alize
d inte
nis
ty
-1000-500 0 500 1000(mA)
2.0
4.0
6.0
8.0
0.1
no
rma
lize
d in
ten
isty
0001- 005- 0 005 0001)Am(
Apr 17-22, 2006 22
Summary
On orbit, the ripple patterns move with respect to the solar spectrum lines because the satellite Doppler motion and temperature changes in TF. But we can calibrate them because they are the patterns fixed to the motor positions.
The spectrum line profiles are significantly improved by the calibration of the intensity ripple using the motor positions of the tuning elements.
Similar wavelength scan data will be obtained at times in flight in order to verify tuning accuracy and the calibration function (amplitude and phase distribution) of the intensity ripple.
Apr 17-22, 2006 23
Broadband Filter Imager (1)
CN bandheadCenter: 388.35nmFWHM: 0.7nm
Ca II HCenter: 396.85nmFWHM: 0.3nm
Apr 17-22, 2006 24
Broadband Filter Imager (2)
G-bandCenter: 430.50nmFWHM: 0.8nm
Blue continuumCenter: 450.55nmFWHM: 0.4nm
Apr 17-22, 2006 25
Broadband Filter Imager (3)
Green continuumCenter: 555.05nmFWHM: 0.4nm
Red continuumCenter: 668.40nmFWHM: 0.4nm