2020/11/18

第11回 光赤外線大学間連携ワークショップ
2020.11.10-12 於 online

小口径望遠鏡用可視補償光学の開発
東京大学天文学教育研究センター
峰崎岳夫

1

本日のお話
• 小口径望遠鏡可視補償光学：私の歩み(2012-18)– 開発のきっかけ– 試験装置の開発– 国内試験観測– チリでの試験観測• 小口径望遠鏡可視補償光学装置：海外– Robo-AO• 「新しい技術と将来」– 試験装置から実用機に向けて

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2020/11/18

補償光学（AO）と私• 私は補償光学の専門家ではありません– 門前の小僧• 学部4年：早野先生の修士論文発表会（岡山188cmでのtip/tilt 補正実験）を聞いていた• 大学院生：すばるAO36の開発（高見先生、大坪さん他）を当時の国立天文台開発実験センターで横で見ていた• 助教：すばるAO188を使った観測研究（共同研究）– 2012年秋の思いつきから手を動かし始める• 2013年度から予算化• 2018年4月の試験観測でひと段落

3

思いつき
小口径望遠鏡
可視波長

大口径望遠鏡
赤外線波長r0〜0.2 m
＠λ=0.5um
r0〜1m ＠λ=2.0um

望遠鏡口径 D=5-10m

望遠鏡口径 D=1-2m• 同様の可変形鏡素子数で同様の角度分解能– D/r0 がほぼ同様（!! ∝ ##⁄$）– λ/D がほぼ同様 → FWHM〜0.1 arcsec

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開発の動機
466

• 補償光学を使った高空間分解能観測
SAKATA ET AL.

Vol. 711– 明るい対象も多い（AGN、重力レンズ、トランジット）– モニター観測、突発現象対応; 気軽に使いたい– 33 –• 中小望遠鏡に補償光学装置がつけばいい

SAKATA ET•AL.可視光なら中小望遠鏡でも sub-arcsec
Vol. 711
分解能が達成可能

Optical flux density(mJy)2−10 keV flux
(10-11 erg s-1 cm-2)

4
3

Epoch 1 2 3 4 5

6

7

2
1

5×Reflection0

Main hard PL

-1
2
1.5
1
0.5
0

-0.5
56300

56400

56500

56600
MJD

56700

56800

16hard PL continuum (filled circles),light curveTM+of the main
Sakata, TM+ 06、画像は HST archive Fig. 4.— (Top) The 2–10 keV fluxNoda,
and that of the reflection component including the Fe-Kα line, after multiplying by 5 (opencircles), both corrected for absorption. (Bottom) A light curve of the B-band flux density of
the NGC 3516 nucleus, derived by applying the differential image photometry to the data of
the Pirka (red), Kiso Schmidt (green), Nayuta (blue), and the Kanata telescope (cyan). The
g ! -band flux density obtained by the MITSuME telescope (magenta) is also plotted, with anoffset of 0.5 mJy added after being scaled (see text).

5

Figure 12. Result of surface brightness fitting for the HST images of NGC3227, NGC3516, NGC4051, and NGC4151. Shown are the HST/ACS images corrected forthe geometric distortion (left panels), the model images of host galaxy+PSF (second left panels), the residual images calculated by subtracting the host-galaxy modelfrom the nucleus-free images (second right panels), and the nucleus-free images calculated by subtracting the distortion-uncorrected model PSF from the original
HST/ACS images then correcting them for the geometric distortion (right panels). All images are aligned as the north is up and the east is left.

小望遠鏡用可視AOの意義

a convergent result with any initial values of the parameters.
3.2. Decomposition of MAGNUM Images into AGN andWe performed the galaxy decomposition by setting almost all
Host Galaxy
parameters to be fitted except for the disk parameters. Since
re 12. Result of surface brightness fitting for the HST images of NGC3227, NGC3516, NGC4051, and NGC4151. Shown are the HST/ACS images corrected forthedisk
parameters
often
convergedatunrealistic
valuesor
To accurately
estimate the host galaxy, we selected a modeometric distortion (left panels), the model images of host galaxy+PSF (second left panels), the residual images calculated by subtracting the host-galaxy
model
diverged images
without
any restriction,
the disk centerat PSF fromthe nucleus-free images (second right panels), and the nucleus-freecalculated
by subtractingwe
thefixed
distortion-uncorrectedmodel
the original
erate
number of observations for each target and filter from/ACS images then correcting them for the geometric distortion(right panels).
All imagesaligned as thethe
north
is up
and theeast isandleft.
the nucleus
locationand areconstrained
disk
scale
lengthMAGNUM monitoring data taken under good and stable seeing
axis ratio within the respective ranges that were defined fromconditions and in the AGN-faint phase. The PSF image wasmajor and minor 3.2.
isophotal
diameters ofofMAGNUM
the target Images
galaxy into AGN
madeandfrom the images of nearby reference stars for each target
nvergent result with any initial values of thetheparameters.
Decomposition
taken
fromallNED. However, we adopted theHost
best-fitdisk scale
AGN. These stellar images were not taken simultaneously withperformed the galaxy decomposition by setting
almostGalaxylength to
be much smaller than those expected from the isophotal
the AGN images, so stable seeing was required for accurate fitmeters to be fitted except for the disk parameters.
Since
diameterNGC 4593,estimate
and 3C120,
smallting. aInmodthis way, more than five nights of images were selecteddisk parameters often converged at unrealistic
valuesforor NGC 3516,
To accurately
the because
host galaxy,
we selectedscale
structureinthecentralregionwithcomplicatedprofileeachfromband, although for some AGNs fewer than five nights
rged without any restriction, we fixed the disk center at
erate number of observations for each target andinfilter
fittedbyanexponential
profileforwereselected
nucleus location and constrained the disk scaleseemed
length toandbe practically
MAGNUM monitoring data taken under good and stable seeing in each band because of the lack of appropriate
NGC 3516
4593 and(Ferruit
et AGN-faintal. 1998; Kormendy
Then,ratio within the respective ranges that were definedfrom and NGC
conditionsin thephase. The PSFdata.
image
was we combined the AGN images and stellar images
et al. galaxy2006), and because
thetheisophotal
diametera bulgenight, respectively, to increase the signal-to-noise ramajor and minor isophotal diameters of the target
made fromimages of
nearby ofreferencestars forfrom
eacheachtargetdominatedwouldThesenot bestellar
a goodindicator
disk
tio and clippedn from NED. However, we adopted the best-fit
disk scalegalaxy AGN.
imageswere fornot thetaken
simultaneouslywith the field region that is the same as the HST field
scale
lengthfor
3C120.
Initialvaluesoftheparameters
wereeach AGN.
th to be much smaller than those expected from the isophotal
the AGN images, so stable seeing was required for for
accuratefitset at smallthose roughly
with
IRAF,
combined and clipped images of target AGNs for eachmeter for NGC 3516, NGC 4593, and 3C120, because
ting.estimatedIn this way,morethanandfive thennightsslightlyof images wereThese
selected
different
values wereselectedtoexaminehow
finalvalues
of
night
were
e structure in the central region with complicatedprofilein each band, although for some AGNs fewer than five nightsfitted to the PSF made as described for the nucleus
parameterswithdifferent
initialband
values.
The skylevellack of component
med to be practically fitted by an exponentialtheprofilefor varied
wereselectedin eachbecauseof theappropriateand to analytic functions for the galaxy component
the parametersdata.
was Then,fitted we
withcombined
its initialthevalue
to beand stellarof bulge
and disk, with the parameters of host-galaxy shape
C 3516 and NGC 4593 (Ferruit et al. 1998;ofKormendy
AGNsetimagesimagesvaluesthetobest-fit
values(scale lengthl. 2006), and because the isophotal diameterzero.
of a Whenbulge-the fitted
from
eachwerenight,unrealistic,
respectively,
increase
the signal-to-noise
ra- and axis ratio) fixed at the best-fit values of thesearched
thetheskyfieldlevel
manually,
the as thesurfacebrightness fitting using the HST data. The sky level wasminated galaxy would not be a good indicator were
for thedisk for bytio changing
and clipped
regionthat isuntil
the same
HST field
resultantwere
sky fluxes
fixed at the mean sky value of reference star images. When χ 2e length for 3C120. Initial values of the parameters
forwereeach found
AGN. to be comparable with those
calculated
from the HRC
user’smanual.
Finally,weadoptedthewasobviouslyat those roughly estimated with IRAF, and thenslightly
These combined and clipped images of target AGNs for each large, we did not fix the disk scale length. Thisvaluesof parameters
thatwereminimized
thethereducedχ 2 . Figures
12– foroccurred
erent values were selected to examine how final
valuesofmainly in the B and I images, probably because ofnight
fitted to
PSF made
as described
the nucleus
14 show
the best-fit
and residual
the HSTparameters varied with different initial values. The
sky level
radial color gradient in a galaxy, arising either fromcomponent
and to images
analytic offunctionsfordata.
the galaxypossible
component
Thesetbest-fitof theare listedofinhost-galaxy
he parameters was fitted with its initial value
to beparametersstellar shape
population gradient or from metallicity gradient (e.g., deof bulge
andgalaxydisk, components
with the parameters
Table 4.
. When the fitted values were unrealistic, the best-fit
valuesJong 1996;(scale length and axis ratio) fixed at the best-fit valuesof theTaylor et al. 2005). However, this had eventually little
e searched for by changing the sky level manually, until thesurface brightness fitting using the HST data. The sky level was
ltant sky fluxes were found to be comparable with those
fixed at the mean sky value of reference star images. When χ 2ulated from the HRC user’s manual. Finally, we adopted thewas obviously large, we did not fix the disk scale length. This2
es of parameters that minimized the reduced χ . Figures 12–
occurred mainly in the B and I images, probably because ofshow the best-fit and residual images of the HST data.
possible radial color gradient in a galaxy, arising either frombest-fit parameters of the galaxy components are listed instellar population gradient or from metallicity gradient (e.g., dee 4.
Jong 1996; Taylor et al. 2005). However, this had eventually little

望遠鏡口径
観測波長
角度分解能
観測可能夜数費用
観測目的

大望遠鏡用赤外線

6-10m
近赤外線（1-4um）〜0.1 arcsec
数晩
高価
暗い天体
高精度観測

小望遠鏡用可視

1-2m
可視(0.4-0.8um）〜0.1 arcsec
豊富「安価」
明るい天体のサーベ
イ、モニター、突発現象

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先行研究• Robo-AO (Baranec et al 2012)– 中小口径望遠鏡(KPNO 2.1m 他)、可視・近赤、LGS– 高度な観測自動化 → large surveys– 高見先生による紹介「中小口径望遠鏡と補償光学系」(2016年）

sensor are dominated by mechanical vibration and pointing errors. The tip-tilt signal is used to drive the laser system’s
uplink tip-tilt mirror, thus keeping the Shack-Hartmann pattern centered on the wavefront sensor.
The high-order wavefront corrector within Robo-AO is a micro-electro-mechanical-systems (MEMS)
deformable mirror16 (Boston Micromachines Multi-DM). Robo-AO uses 120 of the 140 actuators to adjust theilluminated surface of the mirror, sufficient in spatial resolution to accurately fit the calculated correcting shape. The
actuators have a maximum surface deviation amplitude of 3.5 ȝm which corresponds to optical phase compensation of
up to 7 ȝm. In typical seeing at Palomar observatory (median ~1.1"), this compensation length is greater than 5-sigma of
the amplitude of the turbulence induced optical error and therefore results in significant correction headroom.
Furthermore, the deformable mirror is used to compensate for static optical errors arising from the instrument andtelescope at the cost of reduced dynamic range.

https://drive.google.com/file/d/0B7UrUVi26zHwUk1Ja2gtT3ZyRWs/view

Baranec +12

Robo-AO Kepler survey
now 3857 stars(Ziegler+16, 18)

Robo-AO M dwarf multiplicity survey
An Adaptive Optics Survey of Nearby M Dwarfs
6793 targets (Lamman+20)

3

expect less than 45 of the remaining objects to be background giants based on cuts presented in (Lepine & Gaidos 2011). Estimated LSPM photometric distances initially placed the majority of our targets within 30pc,
which often turned out to be a significant underestimatebased on Gaia DR2 parallax measurements (Section 4).
2.2. Robo-AO

Figure 2. The Robo-AO adaptive optics system and science instruments. Light focused from the telescope secondary mirror
enters through a small hole at the center of the instrument before being reflected by 90 degrees by the first fold mirror
towards an off-axis parabolic (OAP) mirror. This mirror images the telescope pupil on the deformable mirror surface. After
reflection from the deformable mirror, an UV dichroic splits off the laser light (violet) and directs it to the laser wavefront
sensor. An additional reversed OAP mirror within the wavefront sensor corrects the non-common path optical errors
introduced by the 10 km conjugate focus of the laser reflecting off of the first OAP mirror. The visible and near-infrared
light (green) passing through the UV dichroic is relayed by a pair of OAP mirrors to the atmospheric dispersion corrector.
The light is then reflected by the tip-tilt correcting mirror to a final OAP mirror which focuses the light towards the visible
dichroic. The visible dichroic reflects the visible light (blue) to the electron-multiplying CCD and transmits the near-infrared
light (red) to a fold mirror and ultimately to the infrared camera. The combined UV, visible and near-infrared light from thetelescope and source simulator can be directed to the adaptive optics and science instruments by translating the first foldmirror out of the way.

7

Figure 1. Our color selection from LSPM with lines of constant photometric distance. These distances are estimatedfrom empirical magnitude-distance relations (Pecaut & Mamajek 2013) and are based on the assumption that these are
all single, main-sequence stars. As high-proper motion, red
objects, the majority of these are likely nearby, northern M
dwarfs.
2. TARGET SELECTION AND OBSERVATIONS

We selected nearby red dwarfs and observed each target with Robo-AO. Follow-up observations were later
done on select targets with Keck. This section presents
the details of the target selection and these observations.
2.1. Target Selection

試験装置の開発

To focus on nearby stars, we selected 7,083 northern (dec > 0 ) targets from the Lépine and Shara
Proper Motion (LSPM) catalog (Lepine & Shara 2005).
Every star in this catalog has a high proper motion(> 0.00 15/yr); nearby objects generally move faster on
the sky than background stars, so a high proper motion
is typically indicative of a close star. To ensure that
our sample of close stars was also apparently bright andred, we then made cuts of V < 16 mag and V J > 3
mag, using the given LSPM values (Fig 1). These cuts
approximately correspond to masses less than 0.6M
and spectral
coolerthan M0 for typical, mainFigure 6. Normalized log-scale cutouts of 32 KOIs with multiple companions with separations<4”types
resolvedwith Robo-AO.
The angular scale and orientation (displayed in the first frame) is similar for eachsequence
cutout, andcirclesare centeredon the& Mamajek 2013).
stars
within50pc (Pecaut
detected nearby stars. Three targets (KOIs 3214, 3463, and 6800) have a possibleAlthoughthird companion,marked arewithdesigned
arrows, to select only inthese criteria
outside our 4” separation cuto↵, as described in Section 4.0.3.
trinsically faint, red stars, seven objects were brighter
than expected for dwarfs (< 6V mag), and we confirmed
all to be known red giants through SIMBAD (Wenger
et al. 2000). These were discarded from analysis. We• まずは「やってみる」– 「技術実証」に目標を再定義– 基本的な SCAO

We obtained 7046 high-angular-resolution images of6793 unique targets over the course of 211 nights between 2015 December 18 through 2017 June 8. Out of
the original sample, 4% (290) of the targets were not observed with the intelligent queue. Each image was takenin the i0 -band with a 90s exposure time. The observations were performed using the Robo-AO laser adaptive
optics system (Baranec et al. 2014) mounted on the Kitt
Peak 2.1-m telescope, masked to a 1.85-m aperture. The
adaptive optics system runs at a loop rate of 1.2 kHz tocorrect high-order wavefront aberrations and images arerecorded on an electron-multiplying CCD (EMCCD) at
8.6Hz which allowed for post-facto image displacement
correction in software using the target as a natural guidestar. The median seeing at the 2.1-m telescope was 1.00 44
which resulted in an average i0 -band Strehl ratio of 4%
and a full-width at half-maximum of ⇠ 0.00 12 (JensenClem et al. 2018). Specifications of the Robo-AO M
dwarf survey are summarized in Table 1.
Table 1. Robo-AO M dwarf survey specifications
Number of targets

6793

Telescope

Kitt Peak 2.1m telescope

CameraAndor iXon DU-888

Observation Wavelengthi0

Exposure time
Field of view

90s
3600 ⇥ 3600

Pixel scale

35.1 mas/pixel

Detector format

10242 pixels

Observation date range

2015 December 18 - 2017 June 82.3. Automated Imaging Pipeline
At the end of each observing night, the Robo-AO system processes and archives observations via automatic
pipelines, detailed in Jensen-Clem et al. (2018). To
summarize, data is first shifted and added in a process that is optimized for either high or low signal-tonoise images. Then, to better detect faint companions,a “high-contrast imaging pipeline” creates a custom, locally optimized PSF-subtracted image of a 3.00 5 cut-out• 可搬型にして複数望遠鏡で試験観測– AOシステム全般にわたる基本技術の習得• AO自体＋調整、較正、望遠鏡取付、観測手順• 安価で「手頃な」AO装置– 可視（R band）– 可変形鏡、波面センサーカメラは安価な市販品– 既製品のレンズ光学系、星像性能評価用小型カメラ– Windows7/10 PC– 性能評価→実用的なシステムの検討

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AO instrument with a laser-guide star system, is mounted on the Palomar observatory 60-inch telescope and the Kitt-Peak
2.1-m telescope and used for research in astronomy.
We started the development of the AO systems for small telescopes, and now we made a compact optical AO instrument
to demonstrate the AO capability. The engineering observation was successfully done in Japan, however, the seeing was
not good. The best performance will be achieved when it is mounted on a telescope at a good seeing site like observatories
in Chile, and we hope to mount it on the 1-m telescope in La Silla observatory to demonstrate the AO capability of 0.1-0.2
arcsec angular resolution. We will briefly overview our AO instrument and show its performance in the engineeringobservation.

2. A COMPACT AO INSTRUMENT FOR SMALL TELESCOPES
2.1 Instrument overview

可視AO試験装置• 体制

TheonAO
we have developed
is a demonstratorof the AO capability for small telescopes in optical wavelength.
AO instrument with a laser-guide star system, is mounted
theinstrument
Palomar observatory
60-inch telescope
and the Kitt-Peak
2.1-m telescope and used for research in astronomy. A bright star is used as the natural guide star for the measurement of the atmospheric wavefront distortion, and it is also
the target, which is observed by the integrated science camera (SC) to measure the point-spread function (PSF) after the
We started the development of the AO systems for small
andnowawemade a optics
compact
optical
AO instrument
AOtelescopes,
system. We
adopt
refractive
using
ready-madecommercial lenses by limiting the observing wavelength to theto demonstrate the AO capability. The engineering observation
was successfully
doneJapan,
however,the seeing
optical. Affordable
camerasare inused
for theWFS andthe SC,wasbecause modest sensitivity is enough to demonstrate andnot good. The best performance will be achieved when it
is mounted
telescope at a goodseeing siteexaminethe on
AOa performance.
The control
PC likeis a observatories
usual desktop PC operated by Windows 7. Accordingly, our AO
in Chile, and we hope to mount it on the 1-m telescope in
La Silla observatory
to demonstrate
the AO capabilityof 0.1-0.2
instrument
becomes a compact
and inexpensive
system witha simple optics. Based on these concepts, we contracted witharcsec angular resolution. We will briefly overview our
AO instrument
showJapan)
its performancein theNishimura
Co. Ltd. and(Kyoto,for the designand engineeringfabrication. The external and internal views of our AO instrument
observation.
are shown in Figure 3.

– 調査、概念設計（峰崎）
2. A COMPACT AO INSTRUMENT FOR SMALL TELESCOPES
2.1 Instrument overview– 設計、製作（西村製作所）
The AO instrument we have developed is a demonstrator of the AO capability for small telescopes in optical wavelength.
A bright star is used as the natural guide star for the measurement of the atmospheric wavefront distortion, and it is also
the target, which is observed by the integrated science camera (SC) to measure the point-spread function (PSF) after the– 制御改良、実験観測、性能評価
AO system. We adopt a refractive optics using ready-made commercial lenses by limiting the observing wavelength to theoptical. Affordable cameras are used for the WFS and the SC, because modest sensitivity is enough to demonstrate and（河野東大４年生卒業研究）examine the AO performance. The control PC is a usual desktop PC operated by Windows 7. Accordingly, our AO
instrument becomes a compact and inexpensive system with a simple optics. Based on these concepts, we contracted with
Nishimura Co. Ltd. (Kyoto, Japan) for the design and fabrication. The external and internal views of our AO instrumentἼ㠃䝉䞁䝃– アドバイザー（大屋先生）
are shown in Figure 3.
Figure 3. The external (left) and internal (right) views of the AO instrument we have developed in thelaboratory.

11x11⣲ᏊShack-Hartmann䝉䞁䝃Figure 4 shows the assembly drawing of the inside of our AO instrument. The incident beam from the telescope is folded
into the optics by M1, collimated by a collimator lens to illuminate the DM. Then, the collimated beam is focused on the
SC by a camera lens, and also the focusing beam is split and folded into the WFS by a dichroic mirror. The optics isdesigned to match the telescope having a focal ratio of F/12. In addition to these main components for the AO system, alaser light source is integrated in the instrument to examine the alignment of the internal optics as well as that between thetelescope and our AO instrument. A calibration light source for the WFS and the SC is also integrated. The base of thechassis is smaller than 50 cm square with a height of smaller than 20 cm, and the total weight is approximately 20 kg. We
summarize the basic specifications of our AO instrument in Table 1.

Allied Vision Tech GE680
䝉䞁䝃䞊䝍䜲䝥CCD⏬⣲ᩘ

640 x 480

䝢䜽䝉䝹䝃䜲䝈

7.4 Pm x 7.4 Pm

可変形鏡
4.74 mm x 3.55 mm
Thorlabs.
DMP40
᭱኱䝣䝺䞊䝮䝺䞊䝖205 fps (@䝣䝹䝣䝺䞊䝮)ཷග㠃䝃䜲䝈
A/Dศゎ⬟(ピエゾユニモルフ40ch
12bit

tip/tiltarm)ㄞ䜏ฟ䛧䝜䜲䝈 with 䡚18e(RMS)䜲䞁䝍䞊䝣䜵䞊䝇

9波面センサーカメラ
wavefront corrector is a piezoelectric deformable mirror DMP40 (provided by Thorlab Inc.). The number of segments
Allied Vision GE680 The
of the deformable mirror is 40, which is more than that required for the optical AO system mounted on a 1-m telescope at
2(400
fps with binning)
the best
seeingsite, (D/rwe
Usually, theamplitude of wavefront tilt caused by the atmospheric turbulence is so large
Figure 3. The external (left) and internal (right) viewsof the
AO instrument
have developedin the0) ≈25.

laboratory.

GigE Vision (1000BaseT)

౯᱁ ~ 25୓෇ 4ྎ౑⏝Figure 4 shows the assembly drawing of the inside of our AO instrument. The incident beam from the telescope is folded
into the optics by M1, collimated by a collimator lens to illuminate the DM. Then, the collimated beam is focused on the
SC by a camera lens, and also the focusing beam is split and folded into the WFS by a dichroic mirror. The optics isdesigned to match the telescope having a focal ratio of F/12. In addition to these main components for the AO system, alaser light source is integrated in the instrument to examine the alignment of the internal optics as well as that between thetelescope and our AO instrument. A calibration light source for the WFS and the SC is also integrated. The base of thechassis is smaller than 50 cm square with a height of smaller than 20 cm, and the total weight is approximately 20 kg. We
summarize the basic specifications of our AO instrument in Table 1.
The wavefront corrector is a piezoelectric deformable mirror DMP40 (provided by Thorlab Inc.). The number of segmentsof the deformable mirror is 40, which is more than that required for the optical AO system mounted on a 1-m telescope atthe best seeing site, (D/r0)2 ≈25. Usually, the amplitude of wavefront tilt caused by the atmospheric turbulence is so large

国内試験観測• 広島大学かなた望遠鏡（2016年6-7月）– 大気条件には恵まれず（雲の隙間からの観測）– PSF がシーイングサイズから有意に改善

1052020/11/18

国内試験観測• 兵庫県立大学なゆた望遠鏡（2016年11-12月）– 好シーイングに恵まれる– PSF が FWHM で ~2倍、ピーク強度で ~４倍向上• 回折限界角度分解能にはまだ足りない（ストレール比~0.02）– mv=4.7 mag でもAO動作を確認

AO ON
FWHM = 0.47 arcsec
AO ON

naturalseeing1”

11

国内試験観測• 兵庫県立大学なゆた望遠鏡（2016年11-12月）– 実験と測定、観測と詳細な性能評価（河野卒業研究）AO ON

rms 波面誤差

Zernike mode ごとの補償光学の効果ある Zernike mode の時間周波数特性（AOあり/なし）と制御モデルからの予想

波面揺らぎの移動測定（→風速~30m/s）

1262020/11/18

海外試験観測• 目的– 良シーイング（FWHM< 1 arcsec）サイトでの試験– 回折限界角度分解能（FWHM ~0.1-0.2 arcsec）が目標• サイトと望遠鏡– ESO La Silla 観測所（チリ）– LSOM 望遠鏡• 有効口径 1.0 m、F/13• 2018年3月に観測– 共同研究者

河野志洋（東京大学）
L. Vanzi, A. Zapata, M. Flores,
S. Ramirez（カトリカ大学）
K. Ohnaka （北カトリカ大学）

チリ運搬時の荷姿（日用品込）

13

海外試験観測• 補償光学による星像の改善– FWHM ≈ 0.18 arcsec、ストレール比 ≈ 0.18 を達成– 星像に回折コアが見られる
0

12

25

38

51

64

90

77

102

115

• http://www.ioa.s.u-tokyo.ac.jp/news/20180406.php

natural seeing

AO ON

AO ON
FWHM = 0.18 arcsec* 積分時間 18 秒

14

7

128

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海外試験観測• 補償光学による星像の改善– FWHM で ~4 倍、ストレール比で ~5.2 倍の向上

0.7
0.6

調整ミスを特定→さらなる性能向上の余地あり
Strehl ratio (bright stars, 18 sec integ.)
PSF •FWHM(bright stars, 18 sec integ.)
0.2
FWHM

ストレール比0.1

0.4

at AO ONat AO ON (arcsec)

0.5

0.3

0.2

0.05

0.03
0.02

0.6 0.7 0.8 0.9 1
2
at AO OFF (arcsec)

0.005

0.01
0.02
at AO OFF

0.03 0.04

15「新しい技術と将来」• 小口径望遠鏡用可視補償光学– 「新しく」はない• Robo-AO SPIE paper 2012
Robo-AO

http://www.ifa.hawaii.edu/Robo-AO/team.html– 「完成品」を「購入する」のも選択肢の一つ• Robo-AO コピー機普及活動• 開発に要する労力を削減
たぶん時間も削減• 独自性はサイエンスで
Robo-AO でやっていないこと

Robo-AOの開発体制(2016年調査、Robo-AO の webから)

16

Robo-AO

The Robo-AO Team (Palomar 2009-2015)
Principal Investigator
Project Scientist
Co-Investigator
Software Lead

Christoph Baranec (U. Hawai'i)
Nicholas Law (UNC Chapel Hill)
A. N. Ramaprakash (IUCAA)
Reed Riddle (Caltech)

The Robo-AO Kitt Peak Team (2015-)
Principal Investigator
Project Scientist
Data Scientist
Robo-AO PI/Inst. Scientist
Robo-AO PS

Shri Kulkarni (Caltech)
Reed Riddle (Caltech)
Dmitry Duev (Caltech)
Christoph Baranec (U. Hawai'i)
Nicholas Law (UNC Chapel Hill)

Students
Graduate

Rachel Bowens-Rubin (U. Hawai'i)*Maïssa Salama (U. Hawai'i)*
Rebecca Jensen-Clem (Caltech)*Dani Atkinson (U. Hawai'i)*Carl Ziegler (UNC Chapel Hill)*
Larissa Nofi (U. Hawai'i)
Amy Ray (Mississippi State)
Gina Duggan (Caltech)
Avinash Surendran (IUCAA)
Kristina Hogstrom (Caltech)
Shriharsh Tendulkar (Caltech)
Undergraduate Jessica Schonhut (U. Hertfordshire/U. Hawaii, '17)*
Celia Zhang (Caltech '18)*
Bianca Avalani (Caltech '17)
Rachel Thorp (Caltech '16)
Chatarin "Mee" Wong-u-railertkun (Caltech '14)
Dan Filler (Univ. of Utah '13)
Corinne Vassallo (Carnegie Mellon '13)
Victoria "Ashley" Villar (MIT '14)
Athanasios Papadopoulos (Aristotle U., Thessaloniki '13)
Ankit Arya (Mississippi State '12)
Alexander Rudy (Pomona '11)
Marland Sitt (Caltech '11)

http://www.ifa.hawaii.edu/Robo-AO/team.html

Christoph Baranec
Rebecca Jensen-Clem
Nicholas Law
Morgan Bonnet

Reed Riddle
Dmitry Duev
Michael Feeney

Observing team (Kitt Peak)
Amy Ray
Mark Trueblood

Megan Nieberding

Science team (Palomar)
Christoph Baranec
John Johnson
Shri Kulkarni
Timothy Morton
A. N. Ramaprakash
Shriharsh Tendulkar
Sergi Hildebrandt
Michał Drahus

Richard Dekany
Mansi Kasliwal
Nicholas Law
Eran Ofek
Reed Riddle
Lynne Hillenbrand
Gregg Hallinan
Leon Harding

Technical team (Palomar)
Christoph Baranec
Mahesh Burse
Hillol Das
Ernest Croner
Jason Fucik
Sujit Punnadi
Reed Riddle
Shriharsh Tendulkar
Kristina Hogstrom
Gina Duggan

Khanh Bui
Pravin Chordia
Jack Davis
Richard Dekany
Nicholas Law
A. N. Ramaprakash
Roger Smith
Jeff Zolkower
Dani Atkinson
Avinash Surendran(* currently active students on project)

Science team (Kitt Peak - under construction)
Shri Kulkarni
Nicholas Law
Rebecca Jensen-Clem

Christoph Baranec
Reed Riddle
Dmitry Duev

Original CAMERA concept and testbed team
Matthew Britton
Viswa Velur
Dan Beeler (Pomona '09)

Technical team (Kitt Peak - under construction)

1/2

Nicholas Law
Lothar Ratschbacher (U. of Vienna '08)
Wojciech Makowiecki (Jagiellonian U. '08)(c) 2009-2015 Robo-AO Collaboration.

2016/11/25 3:19

2/2

2016/11/25 3:19

8

2020/11/18

実用機開発に向けて• 試験機の限界– 可変形鏡の応答速度とストローク– WFS カメラの読み出し速度と感度– → 試験機ほど「安価に」というのは難しい• 可視補償光学の原理的な難しさ– 制御速度がより高速– 明るいガイド星が必要– 視野が狭いフリード長%! ∝ '#⁄$

Coherence 時間&'( ∝ '#⁄$×*%

WFS サブアパーチャ内
露出あたりフラックス&'+ ∝ ''(⁄$×*%

補償可能視野,! ∝ '#⁄$×ℎ&'

17

実用機開発に向けて• レーザーガイド星が必須– ナトリウムレーザー（すばる望遠鏡ほか）• ナトリウム層（~80-100 km 上空）で励起– レーリーレーザー（Robo-AO）• パルスレーザーの後方散乱シグナルの受信タイミングを制御– ガイド星高さは低い（~10 km 上空）が小口径なのでOK• 紫外線レーザー– 「eye safe」でスポッター不要→自動化• 市販品、ナトリウムレーザーより安価• 光学系、WFS カメラが紫外線に対応する必要– 国内の法的規制は？

1892020/11/18

実用機開発に向けて• やっぱり赤外線（J band)– 可視補償光学の原理的な困難がそこそこ緩む• R band → J band で波長は 〜２倍– 国内シーイング条件下での波面補償性能向上– 装置開発の観点から• 可視波長域全部を WFS に使える
• レンズ系もわりと普通に使える– 試験観測の結果からざっくりと性能予想• シーイング FWHM=1.0 arcsec（R band）、口径 2m– →可視補償光学より角度分解能が向上

R band with AO（実績）
J band with AO

ストレール比FWHM

0.02

0.5 arcsec

0.1-0.18(回折コア:0.13 arcsec)

19

4.2 Synergistic projects
We have established an educational collaboration with Pomona College which has proven to be particularly fruitful. This
4.2inspired
Synergistic
projects of a new AO lab at Pomona aimed at hands-on education of undergraduates, and thecollaboration
the creation
deploymentWeof havea natural-guide-starversion collaborationof Robo-AOwith
on Pomona
their 1-m
telescopeat Table
As partof theestablished an educational
Collegewhich hasprovenMountain.
to be particularly
fruitful.
This
ongoing collaboration,the
Robo-AO
has supplied
AO systemwiththe full
real-time
Robo-AO software
collaboration inspired
the creationof a new the
AOPomona
lab at Pomona
aimed athands-oneducationof undergraduates,
and theengine. The
prototypeofPomonasystem, dubbed
൏KAPAO-Alpha൏,whichbasic operation
naturaldeploymenta natural-guide-starversionof Robo-AO on
their demonstrates
1-m telescopetheat Table
Mountain. of
Asapartof the20
guide star adaptive
system thehasRobo-AO
recently closed
the AOtheloop
on-skytheir withresults
reported.
ongoing optics
collaboration,
has supplied
PomonaAOand
systemthehavefull recently
real-time been
Robo-AO
softwareengine. The
prototype൏KAPAO-Alpha൏,
whichdemonstrates
basic operationof a natural
The final KAPAO
system(no Pomona൏Alpha൏),system,
whichdubbed
will bea remote-accesssystemofferingthesimultaneousdual-band,
20
guide
star
adaptive
opticssystemhas
recentlyclosedtheAO
loop
on-skyandtheirresults
haverecentlybeenreported
diffraction-limited imaging at visible and near-infrared wavelengths, delivering an order-of-magnitude improvement in .
final KAPAO
systemresolution(no ൏Alpha൏),whichwillcurrent
be a remote-accesssystemoffering simultaneousdual-band,
point sourceThesensitivity
and angular
relativeto theseeing limits isin development
and is expectedto21
diffraction-limited
imagingatvisibleandnear-infrared
wavelengths,
deliveringanorder-of-magnitudeimprovement
be deployed in the near future . Beyond the expanded scientific capabilities enabled by AO-enhanced resolution and insource sensitivitynature
and angular
to the current
limitsin development
and is expected
sensitivity, point
the interdisciplinaryof the resolution
instrumentrelative
development
effort seeing
providesan is
exceptional
opportunity
to train to
be deployed in the near future21. Beyond the expanded scientific capabilities enabled by AO-enhanced resolution anda broad rangeof undergraduate STEM students in AO technologies and techniques. The Pomona Table Mountain AO
sensitivity, the interdisciplinary nature of the instrument development effort provides an exceptional opportunity to trainsystem is an exciting example of how Robo-AO can expand the interaction between research and learning througha broad range of undergraduate STEM students in AO technologies and techniques. The Pomona Table Mountain AO
adaptive optics.
system is an exciting example of how Robo-AO can expand the interaction between research and learning through

天文学研究以外の意義• 技術習得と学生教育– 試験装置の開発は大変に有意義であった
adaptive optics.

• The
全体が理解できる、気軽に実験できる、簡単に改善できる
4.3 Outreach
Robo-AO
collaboration has published a web site detailing the goals, science and technical details of the project,
4.3 Outreachaccessibility to the general public: http://www.astro.caltech.edu/Robo-AO/. Updates are provided,
highlightinggeared
major towards
project milestones.
– 最先端補償光学装置開発との距離が遠い？
highlighting major
projecttomilestones.
Disseminationof results
the broader public, including interpretation of science discovery and its impact ongeared towards
accessibility
to the generalpublic:http://www.astro.caltech.edu/Robo-AO/.
Updates
areofprovided,
The Robo-AO
collaboration
has publisheda website detailing the goals, science and technicaldetails
the project,broader public,
interpretationof science discovery
and its impact
are Dissemination
madetoof results
theto thepublic
by including
Palomar
Observatory’s
VisitorCenter on• society,
学生の「形に残る」成果、キャリアパス、安定した予算
society,
are
made
to
the
by 100,000
Palomar
Visitor kiosk
Center(http://www.astro.caltech.edu/palomar/exhibits/)
which publicdraws overvisitorsObservatory’s
annually. A web-based(http://www.astro.caltech.edu/palomar/exhibits/)
which
draws
over
100,000
visitorsannually.
A
web-basedkiosk
highlighting adaptive optics science is on display in the Visitor Center and available on the web. The
presentation highlighting adaptive optics science is on display in the Visitor Center and available on the web. The• presentation
最先端大型プロジェクトの一部を分担するほうが近い？
observatory
has also embraced other online social media, and the results Robo-AO commissioning have appeared on
observatory has also embraced other online social media, and the results Robo-AO commissioning have appeared on• アウトリーチ

Palomar Observatory’s
blog and Facebook page.
Palomar Observatory’s blog and Facebook page.
In addition,In Robo-AO
has recently
been augmented
with anwith
eyepiece
for theviewingof visible-light
addition, Robo-AO
has recently
been augmented
an eyepiece
fordirect
the direct
viewingof visible-light
adaptive optics
corrected
objects (Fig.
7).(Fig.
The 7).
eyepieceis fed isbyfed
a selectablevisiblebeam
splittingmirroradaptive
optics astronomicalcorrected astronomical
objects
The eyepieceby a selectablevisiblebeam
splittingmirrormounted onaremovable
kinematic
base
betweenthevisibledichroic
andvisiblefilterwheels.
This
allowsforformounted on a removable kinematic base between the visible dichroic and visible filter wheels. This
allowssimultaneous
imaging withthe visible
While accesscurrently
limited,we intend
to support
futureeyepiecesimultaneous
imagingwith thecamera.
visible camera.
While isaccessis currently
limited,we intend
to support
futureeyepieceobserving byvisitingby
astronomyclasses from
Caltechand Pomona
College.
observing
visiting astronomy
classesfrom Caltech
and Pomona
College.

– 眼視補償光学

Robo-AO
Baranec +12

Figure 7. Members of the Robo-AO team observing Mars with the eyepiece attached to Robo-AO (left). Simultaneous i-

20band imagesof Robo-AO
Mars captured
adaptive
optics(middle)and with
the Robo-AO
running (right).
Figure 7. Membersof theteamwithoutobservingMars
withcorrection
the eyepiece
attached
to Robo-AO(left).system
Simultaneous
iband images of Mars captured without adaptive optics correction (middle) and with the Robo-AO system running (right).

5. FUTURE WORK
5.1 Infrared camera upgrade

5. FUTURE WORK

5.1 Infrared
upgradeThecamera
Robo-AO
collaboration is currently in the process of upgrading the infrared imaging system from an engineering
grade camera to a low-noise wide-field imager using a 2.5 ȝm cutoff Teledyne HAWAII-2RG™/HgCdTe detector (H2The Robo-AO
collaboration is currently in the process of upgrading the infrared imaging system from an engineering
RG). The science grade H2-RG detector has ~ 0.01 e-/sec dark current, < 5 e- readout noise22 and slightly higher
grade camera
to a low-noise wide-field imager using a 2.5 ȝmcutoff Teledyne HAWAII-2RG™/HgCdTe detector (H2quantum efficiency than the InGaAs, offering 45-80
times more sensitivity (Table 3).The new camera will consist of a
RG). The science grade H2-RG detector has ~ 0.01 e-/sec dark current, < 5 e- readout noise22 and slightly higher
quantum efficiency than the InGaAs, offering 45-80 times more sensitivity (Table 3).The new camera will consist of a10

2020/11/18

まとめ• 小口径望遠鏡可視補償光学– Sub-arcsec 高角度分解能+ サーベイ、モニター、突発天体; 気軽に観測• 試験装置の開発– 安価な可搬型SCAO装置– 試験観測：国内望遠鏡→海外適地で回折コアの観測成功• 新しい技術と将来– 実用機にはレーザーガイド星が必要(新しくはない)– J band なら可視より良い星像が得られそう（国内向き）– 学生教育: 最先端補償光学研究への橋渡し– アウトリーチ的にアピーリングかも– 開発する意義と予算

21

11