GRAINE計画 :気球搭載型大口径エマルション望遠鏡による10MeV-100GeVガンマ線の高解像度・偏光観測高橋 覚 (神戸大)for GRAINE collaboration
Shigeki Aoki(1), Kaname Hamada(2), Toshio Hara(1), Katsumi Ishiguro(3), Atsushi Iyono(4), KeikiKamada(1), Hiroaki Kawahara(3), Nobuko Kitagawa(3), Koichi Kodama(5), Ryousuke Komatani(3),Masahiro Komatsu(3), Motoaki Miyanishi(3), Fukashi Mizutani(1), Saki Mizutani(1), KunihiroMorishima(3), Naotaka Naganawa(3), Tatsuhiro Naka(3), Ryo Nakagawa(1), Yuji Nakatsuka(3),Mitsuhiro Nakamura(3), Toshiyuki Nakano(3), Kimio Niwa(3), Keita Ozaki(1), Hiroki Rokujo(3),Takashi Sako(3), Yoshitaka Saito(5), Osamu Sato(3), Yoshihiro Sato(6), Emi Shibayama(1),Takuya Shiraishi(3), Atsumu Suzuki(1), Kazuya Suzuki(3), Satoru Takahashi(1), KeisukeTamura(2), Syuichi Tawa(1), Ikuo Tezuka(6), Junya Yoshida(3), Tetsuya Yoshida(2) and MasahiroYoshimoto(2)(1)Kobe University, (2)ISAS/JAXA, (3)Nagoya University, (4)Okayama University of science,(5)Aichi University of education, (6)Utsunomiya University

PI : 青木 茂樹 (神戸大)1873 sources

Nuclear emulsion

Microscopic view
10microne+/-Gamma-raye-/+Cross sectional view of an emulsion film
Powerful tracking device>High spatial resolution : ~1micron>Small radiation length : 0.002Xo

Gamma-rayEmulsion

Plasticbase

Emulsione-e+

0.3mm(0.002Xo)
High angular resolution for gamma-ray
Sensitive to gamma-ray polarization

GRAINE

Gamma-Ray Astro-Imager with Nuclear Emulsionγ

Converter
Convertere- e+Emulsion
Emulsion ++ Copper
Copper foil
foilTimestamper
Timestamper
Multi-stage
Multi-stage shifter
shifter

Calorimeter
Calorimeter
Emulsion
Emulsion ++ metal
metal plate
plate

AttitudeAttitude monitor
monitor* 10m2*εtrans*εconv*εdet

StarStar camera
cameraFermi LAT
Angular resolution @100MeV@1GeV

6.0deg (105mrad)

GRAINEx1/6

1.0deg (17mrad)

0.90deg (16mrad) x1/9 0.1deg (1.7mrad)

Energy range

20MeV - 300GeV

10MeV - 100GeV

Polarization sensitivity

NoYes

Effective area @ 100MeV

0.25m2@ 1GeV
Dead time

0.88m226.5μsec(readout time)

x8x3

2.1m2 *
2.8m2 *
Dead time freeHigh resolution imaging
GRAINE(Simulation)

0.5deg

W44
Abdo et al., Science, 2010
Color : 2-10GeV gamma-ray (Fermi LAT)
Contour : IR(Spitzer)

・3flights (41.7m2days)
・>1GeV
・Smearing IR(Spitzer) distribution
with 0.08deg(1.4mrad)
・Considering atmospheric gamma-ray(>1GeV) as BG

Emulsion production
Gelatin1/4, Na type, Fe x 2, MIP (XAA, 20deg, 40min)

New type

GD=86.1+-4.7
FD=2.9+-0.9

OPERA type

GD=34.8+-0.6
FD=3.7+-0.4

Evaluated by K. Kamada (Kobe Univ.)

efficiency [%]Fuji Janet Co., Ltd., Nagoya Univ.

GRAINE 2011

Tracking efficiency
97.7+-0.25 [%]Incident angle

Automated emulsion read-out system (Nagoya Univ.)
Hyper-TS: Next Generation Read-out system

Scanning speed
9000cm2/h (design)Multi-stage shifter~sea level12hours2stages)

RMS

1.5s

Efficiency

98%Reliability97%hour))min.
)))

sec.

S.Takahashi et al., Nucl. Instr. And Meth. A, 620 (2010) 192-195
Consists of emulsion films with Small R.L., High pos & ang resolution
 Low P threshold, High reliability, High efficiency, Large scale
Simple component, Compact, Light, HV free, Low power consumption, Dead time freeAngular resolution
SPring-8 LEPS
UVSOR

Grain
bygrainFermi-LAT(P7SOURCE_V6)

Kinematicallimit

BackTotal
Front

GRAINE(MC)emulsion film(70,180,70) 1film

2films3films100MeV

1GeV

10GeV
Gamma-ray energy

Polarization sensitivity
SPring-8 LEPS

preliminary

N(ω)=p2*{1+p0*cos2(ω-p1-90°)}

Consistent with beam expected

Source sensitivity

byGraingrain

100MeV

1GeV

10GeV

100GeV
Gamma-ray energy

MDP =2 RFsε eff

1flight 10

5x10-6

3C45
4.
3fla

re 2W
LS44 1
PKI+6
S 1315 010 3 1LA-081TPPS SR RJ
J1 2070 219- +444 03C29451C 4C rab .3 1
T 1
PKA 1
PK S 0 2 2S0 132
PG KS 40 9-0em 2 4
1 3C ing83 362 9 fla
a 10 f r
PK273 -21 lare e
1 2flaPK S B flar
S1 12 e 2 re
51 220- +208 169 fla
Vefla rre 2
C la 1rabfla
re 2Minimum Detectable Polarization

Polarization sensitivity

0.5

πS Fsε eff + FBG ΩAeff Teff

Modulation factor : R=0.1
BG : Staib et al. (1973), 4.5GV, 12GV

4.5GV
12GV
12GV, Grain by Grain

12FGL, 2Monitored Source List Light Curves

Flux (>100MeV) Fs [cm-2s-1]

GRAINE roadmap•

8th/June/2011, TARF, JAXA Scientific Ballooning, PI : S. Aoki (Kobe Univ.)
12.5cm x 10cm aperture area, 4.3hours (1.6hours@35km) flight duration– Working test for each component– Connection test between components– Measurement of atmospheric gamma-rays•2014(Planned), Alice Springs, JAXA International Scientific Ballooning
2500cm2 aperture area, 1 day flight duration– Overall test by detecting known gamma-ray source– Observation with highest imaging resolution•

201510m2 aperture area, 7days flight duration– Starting scientific observation

Emulsion chamber
Aperture area : 12.5cm x 10cm

Flatness
Flatness compensation films

Low energy

High energy OPERA film x 2

Converter
Converterγγ

102 emulsion films, 91 copper foils (50µm)
1.1kg, 35.0mm, 0.54Xo(εconv= 34%)

Honeycomb board
Honeycomb boarde+e-e+

OPERA film x 10 (go-ban part)
OPERA film x 88 + Copper foil x 88
New type gel film x 4 + Copper foil x 3-Target & Detector-Precise measurement of incident direction-0.08deg@1-2GeV, 0.93deg@100MeV-Measurement of gamma-rays polarization-Interface of timestamper-Energy measurement of gamma-rays (<~GeV)-Momentum measurement of electron pair with MCSe-TimestamperTimestamper))))))

1st : OPERA film x 2
2nd : OPERA film x 2
3rd : OPERA film x 2
New type gel film x 1

Calorimeter
Calorimeter

32 emulsion films, 10 (0.5mm) & 17 (1mm) lead plates
3.2kg, 31.9mm, 4.0Xo (Shower Max.@ a few GeV)OPERA film x 5 (go-ban part)(OPERA film + lead plate(0.5mm))x10(OPERA film + lead plate(1mm))x17

Number of tracks:8.0×108

10cm

12.5cmFilm#67, 1stNumber of tracks:8.0×108

10cm

12.5cm|tanθproj|<1200micron

Film#67, 1stNumber of tracks

Track reconstruction
RawClustering

Both sides

Between films

BottomTop
Film#

Reconstructed tracks (film#1-16) : 8.7x107 (overlap)

ZY(5mm)2 x10films X
2x104tracks

ZYX

ZYX

10.0cm

12.5cm153events
Reliability 97%

Zoom upOne of gamma-ray events
EventStart
θincident(pβ)left(pβ)rightEγ: 71 6923485: #7: 9.748 [deg]: 60 +20 -12 (25%) [MeV/c]: 32 + 9 - 6 (22%) [MeV/c]: 92 +22 -13 (+24% -14%) [MeV]#73.15mm

0.077mm#1

Establishment of timestamp technique
H.Rokujo, et al., NIM A, 701 (2013) @GRAINE2011“Multi-stage shifter” 1st model

Track rate mesurement@35km
excess
(6.6σ)

Detection of
hadron events
Aperture area: 12.5 x 10 cm2•Correct operation during whole observation time
•Giving time info. to all penetrating tracks•Detection of hadron shower tracks by timing and3-D spatial analysis•Time resolution: 0.15 sec

Hadron induced event
Ev : 2438038
Eγ : 45+33-10[MeV]θγ : 46.61[deg]7:18:34.5 (JST)∆t=+-0.5s
Convergence
1.2cm x 1.2cm
x 16films

Pointing accuracy∆θspace : 0.65deg(0.0114rad)andidate

Ev : 7797344
Eγ : 100+64-23 [MeV]θγ : 38.96 [deg]8:15:52.9 (JST)electronc

Electron induced event∆t=+-0.5s∆r<1mm, ∆θ<60mrad

γe- pairConversion point

67µm, 21mrad

Angular resolution
SPring-8 LEPSUVSORGRAINE2011
Zenith:0-47deg(Preliminary)
Grainbygrain

Fermi-LAT(P7SOURCE_V6)

Kinem
aticallimit

BackTotal
Front

GRAINE(MC)emulsion film(70,180,70) 1film

2films3filmsGamma-ray timing accuracy
RMS : 0.15[sec]Preliminary

Eγ : 45-245[MeV]θγ : 0-47[deg]45[MeV]46.61[deg]

-0.4

-0.2

00.2

0.4

∆t[sec]

大気ガンマ線フラックス

Preliminary

Attitude analysis

Daytime star camera view

Star catalog data

8:11:00(JST) @35km

pattern match

K. Ozaki et al.,Proc. of Balloon Sympo.,
isas12-sbs-022

Working rate: 74 %Monitoring
accuracy: < mrad
Elevation < 0.25mrad
Azimuth < 0.44mrad

Rotation speed of the balloon
95% time during level flightwas ω <0.15deg/sec.

It is important to decide telescope
attitude to celestial coordinate
better than emulsion angularresolution(0.08deg).

We confirmed attitude decisionaccuracy was <ωω σt< 0.02deg.

GRAINE
First Light285683111

139

Exposure
167 [cm2 hour]

GRAINE roadmap•

8th/June/2011, TARF, JAXA Scientific Ballooning, PI : S. Aoki (Kobe Univ.)
12.5cm x 10cm aperture area, 4.3hours (1.6hours@35km) flight duration– Working test for each component– Connection test between components– Measurement of atmospheric gamma-rays•

2014(Planned), Alice Springs, JAXA International Scientific Ballooning
2500cm2 aperture area, 1 day flight duration– Overall test by detecting known gamma-ray source– Observation with highest imaging resolution•

201510m2 aperture area, 7days flight duration– Starting scientific observation

Flight model of multi-stage shifter

12.5cm2011 model

Co-developed with
Mitaka Kohki Co., Ltd.

10cm

Next model
Aperture area : 2500cm2