Imaging detection for GRBs & SNe with high sensitivity andgood polarimetry by Electron Tracking Compton camera

SMILE-II

1.
2.
3.
4.
5.

CONTENS
Problem of MeV gamma ray observation
Electron Tracking Compton Camera
Performance of SMILE (+Polarization measure)
Expected MeV Astrophysics in GRB, SNe & AGNs
Summary

T.Tanimori, H.Kubo, K.Miuchi2, J.D.Parker, S.Komura, S.Iwaki, T.Sawano,K.Nakamura1, S.Nakamura, Y.Matsuoka, T.Mizumoto3, Y.Mizumura, M.Oda. S.Sonoda,A.Takada, D.Tomono,Toru Tanimori
08/11/2013 SN-GRB Workshop
Department of Physics, Kyoto Univ., Kyoto, Japan

1) Department of Physics, Kyoto University, Kyoto, Japan,
2) Department of Physics, Kobe University, Japan,3 )Research Instit. for Sustainable Humanosphere, Kyoto Univ.

COMPTEL(1-30MeV)COMPTEL

SN, GRB-> 1-150keV

INTEGRALV. Schönfelder+ (ApJS, 1993)

gamma

φeventcircleMain reasons of Difficulty
1.
Huge BG of gammas & fast neutrons
2. Obscurity of imaging by circular direction
If no BG, severalx10cm2 => a few mCrab@106sec

Effective Area
~13cm2@1MeV

V.Schönfelder (2004) SuggestionLow background is most important for next
MeV detector
1.
2.
3.
4.
5.

Good angular res.(ARM) = good Energy res.
Redundancies (TOF, Kinematics, dE/dx ）Measurement of electron direction (SPD)!
Low-z material and light weight
Short timing gate

Advanced Compton Camera. Aprile et al(2004)

M. S. Bandstra et al. ApJ 2011

Liquid Xe TPC
2000
No VETO
0.1-10MeV Expected eff.A～20cm2
No. detection for Crabpriority: Large effective Area large

Crab 4s (8hrs) with MLEM meth.
Ge detector with BGO VETOFoV 3str , DARM 7.3o (FWHM)
0.3-1.5MeV Eff.A 6cm2
Simulation 3800 g detection 667 g
B.G. in Crab view~29000(S/N~0.02)
Priority: good energy res.

Electron Tracking Compton Camera(ETCC)
Goal: High sensitivity for Continuum gammas
with > ~50 better than COMPTEL
Strong BG rejection & clear imaging are needed
1. Electron tracking for imaging,Kinematics(a)+dE/dx (multi redundancies)
2. Large FoV. ~3str & No Veto counter! 50cm-cubic 3atm CF4 gas ~110cm2@1MeV
SMILE-II(dE/dX)

cosmic μneutronCompton e-10cm-cube m-TPC & ETCCGSO:Crystal

Timing Projection Chamber (TPC)

3x3 array

ETPCem-PIC
Micro Pixel Chamber

GSO
Pixel
11%@ 662 keV(FWHM)

400mm

protonelectron

SPD ~160oSub-MeV g-ray Imaging Loaded-on-balloon Exp. (SMILE-I)
2006 Sep.
Neutron background

All Trigger # 2.3x105 (3hours)
Signal  ~420(down going) +500(up)Simulation  ~400 (diffuse cosmic)

Diffuse Cosmic g

Event Selection
Takda et al.ApJ (2011)

Crab Observation for 104s with 5s detection
From SMILE-I,
Effective area 1 cm2

DARM 10o

But SMILE-I= : 1mm2 ->x100 Improvement① Physical process• Recoil e stopping in TPC• Scattered gamma absorbing②Reconstruction Inefficiency; ~10% in SMILE-I

TPC30cmGSO

GSOGSO

If Recont. Eff. -> 100% SMILE-II(30 cm)3 TPC x 20 times of SMILE-I
Reconst. Eff. ⇒ X 10 Angular Res. 20o=>5.3oImaging Test in 30cm ETCC
137Cs(～0.85MBq)

Noise reduction by Energy
loss rate dE/dx⇒ Continuum fully gamma events
selected by dE/dx cut

Energy Cut
Diffusegamma

Performance in 30cm-cube ETCC

 Field of View (3str)

137Cs(～0.85MBq) 2m

137Cs

dE/dX cut

BG30°

Angular Resolution & Energy band in 30cm-cube ETCC
Angular Resolution（FWHM）@662keV
5.3 deg.

Energy Resolytion (FWHM)

93 deg.
18 %＠ 166 keV Multi energy > 300 keV
137Cs
sources

11 %＠ 662 keV

@ 2m
22Na

30°

LaBr3(simulation)

133Ba

GSO(simulation)60°

0.85 MBq
0.16 MBq
0.63 MBq

Imaging Improvement bySPD
LegacyRyan, J. M., NewAR, 48, 199 (2004).

:Advanced(SPD=200°)

137Cs×3

3.2MBq
0.85MBq
0.74MBq

RI⇒ (～4times better contrast image

Detection Efficiency & Effective Area

 Present Eff. Area～1cm2Eff. Area～1cm2
SMILE-II(30cm FM)

Compton electrons in TPC->100% detection

without side PSAs

SMILE-II(10cm proto.)

Simulated Effective Area

SMILE-I(10cm)

Further improvement⇒CF4 + 3atm Eff. Area ～10cm2+ double of Scintillator ->Total ~20 cm2 @ SMILE-II

Similar effective area to COMPTEL
But 3str FoV, Low background, Clear Imaging in SMILE-II

Weak source detection such as Crab
 RI：22Na
Zenith = 26o.
z = 2m, 31 kBq
1/4 of total system
Operation22Na
22Na

BG
Spectrum after dE/dx Advanced Compton Image

S/N = 0.019
a few times stronger source
than crab for SMILE-IIPerformance Test under intense radiation condition
using 140MeV proton beam 2013 –Oct.
150MeV proton

Trigger rate 300-500HzBalloon trigger rate 60HzETCC operation under intense MeV Gammas& Neutrons from water target

Modulation Factor in SMILE-II in Simulation

Un-polarized, Cos θ < 0.7 0o, 100%, Cos θ < 0.7#EventMaxMinMF

Un polarized

5.33e50o, 100%

4.69e5

1.4

0.35

0.60

45o, 100%

4.83e5

1.45

0.35

0.61

MF = (max-min)/(max+min)

45o, 100%, Cos θ < 0.7

New Balloon Exp. （SMILE-II & III）

天文学会
（＠東北大学）2013/09/11 (水)106 sec, 3σ detection

Crab SMILE-IIPreliminary

KirunaJapan
Eff.Area 2cm2

SMILE-III (10cm2)

SMILE-satellite

 ＳMILE-II （in USA）

 Collaboration with Goddard( now planning) 30cmETCC with 1~4cm2
 Detection Crab ,CygX-1 at >5s
 Polarization

SMILE-Satellite
40cm-ETCC (eff.A ~40cm2)x4

 ＳMILE-Ⅲ（Polar region）
 upgrade to ~15cm2 X2 ETCCs

 Deep Survey for galactic plane

TerminatedSETCC(4unit)

ACTGRIPSCASTScatt, material

gas

SiSiSiSi

Absorber

GSO/LaBr3Ge

LaBr3

CdTe

CsIgVETO

nothing

BGO/CsI

nothing

BGO

nothing

Tracking○×△×△

Eff. Area

40x4 cm2~103 cm2

190m2

10-30 cm2

20 cm2ARM

2.3°@ 1 MeV

1.2°@ 1 MeV

1.8°@ 1 MeV

2.5°@ 1 MeV

2.0°/5.5°@ 1 MeV

FoV

3 str

3 str

Sensitivity
MeV/cm2/s

4.4e-6 @ 0.5 MeV
6.5e-6 @ 1 MeV
4.7e-5 @ 5 MeV

1e-5 @ 1 MeV

3e-5 @ 1 MeV
7e-4 @ 5 MeV

MEGA

6e-5 @ 1 MeVCrab & CygX-1 fluxes ( SMILE-II)
Crab polarization above 200keV(Integral/IBIS)
P=0.46+0.3-0.19(Integral/SPD)
P=0.4+10-10%

Cyg X-1
Crab flux

Cyg X-1 above 400keV
P=67+30-30%
IBIS M=0.3 SPI were notcalibrated on the ground as apolarimeter.

E>100keV, 1cm2 ETCC 1300 gamma /10hrs from Crab
BG 6500 gamma /10hrs MPD＝28/M %4cm2 MPD=12/M
10cm2 28/3.3=8.5/M %M:modulation factor M > 0.6 expected for ETCC (Low backgroundcompared to IBIS due to real imaging )Anisotropyof MeV CMB（from Y.Inoue）
Precise measurement of MeV CMB• 0.1-10MeV Dominant
contribution is unclear
Seyfert or FSRQ?
• SMILE-III Polar flight

Polar Flight (~106 sec) ⇒ >106 events⇒ precise spectrum of CMB
Anisotropy⇒ >105 events is enough forseparation ofSeyfert and FSRQ with 5s

GRB Detection with Swift
BAT 15-100keV X-rays

Swift GRB(08-09)
z Relativisitc dilationhz~(1+z)-1htime

Trigger bias looks to appear above for long GRB with z>4

Imaging GRB Trigger in Sub-MeVImaging ability for each photon
Even 10o x10o -> 1/100 B.G. of 1
str Detector->Imaging Trigger photon byphoton in ETCC
GRB detection limit~70 ph. >100keV in 4ox4o@~100cm2 in 103 sec (8s)
Point Accuracy for GRBs
<0.2o for 300g, 0.5o for 30g

GRB Cosmology~650 GRBs/one year &10 with z>10 /10years
from GRIPS proposal

POP-III

Expected g in S-ETCC for GRB @z=20 &Eiso=1052 erg -> a few x100 ph.

Fluence

ETCC could detect weak flux long duration
GRB efficiently
At least relativistic dilation effect (x~10)

POP-III

From Dr. Suwa40cm-cube ETCCGRB of 10-2x10-10erg/cm2s (900Msolar)
Eff.Area 40cm2• 103s 200g B.G. 35g in 4x4o S/N ~18s
• 105s 2x104g B.G> 3.5x103g S/N=330s• 5s detection during 105s -> ~300g
a few 10 Msolar Super long bursts OK!

GRB detection in SMILE-IIIObservations
1.

GRB 021206: 80+-20% (Coburn & Boggs 03)

2.

. GRB 930131, GRB 960924: > 30% (Willis et al. 05)

3.

GRB 041219a: 96+-40% (Kalemci et al. 07; McGlynn et al. 07)]

4.

GAPS 27+- 11%, 84+16-28%, 70+-22% Yonetoku et al.2011••

SMILE-III GRB~ No background
Calibration by Crab!
ETCC M＞0.6 FoV 3str, Eff. Area 30cm2@200 keV
GRB 10-6erg/cm2s ~250 photon/s T90=40s 250x40s ~104
MDP = 4.3/M % (3s) (M＞0.6 )7% polarization OK！
GRB 10-7erg/cm2s- 24% polarizationa few GRBs (10-6erg/cm2s) ~10 (10-5erg/cm2s) with one-month& low fluence and long duration GRB•

Satellite ETCC～160㎝2 （Sensitivity~1mCrab@106sec）
10-7erg/cm2s GRB
MDP =5/M % (>100 GRB/year)
10-6erg/cm2s GRB
MPD= 2/M % (several 10 GRB/year)

MeV Gammas from SNe• SMILE with laBr3 dE/E ~3%@900keV(FWHM)• Sensitivity for line g ~5x10-6 g/cm2s (SMILE=III Eff.Area 30cm2)~5x10-7 g/cm2s (Satellite-ETCC: Eff. Area ~160cm2)

From Maeda et al ApJ (2012 )SN 1a ~20 /several years observation within 20Mpc
Collapse type SNe ~5 from GRIPS proposal

Galactic lines of SMILE-III
3511keV, 1804keV(Al-26), 4MeV (C-12)
511keV map (INTEGRAL)

137Cs×3 @ 2m21~30°
0.74 MBq

0.85 MBq

0-1
3.2 MBq-2-330°30°

0.00150.002

0.0025

L. Bouchet+ (2010)
1 pixel = 5°×5°

0.003-3-2-101

23X [m]

Simple backprojection image
More fine imaging is
obtained by using
MLEM

Photons/cm2/sec

Polar Flight (SMILE-II 10 cm2, 106 sec) ⇒ > 103~104 event/pixelMore detailed map of 511keV due to point-like direction of gamma rays
In addition, survey for galactic plane ⇒ possible detection of new sources
due to low background and point-like directional imaging of ETCCETCC have obtained both strong background rejection abilities andhigh contrast imaging by direction of recoil electron.
ETCC has nearly one order better sensitivity than usual CC withsimilar effective area.
ETCC also is a good polarimeter with MF>0.6 in sub-MeV region.
SMILE-II having 1-4cm2 @0.3MeV effective area will be planned inUSA in 2014, 15 for the observation of Crab and Cyg.X-1 with oneday flight. (>5shigma detection, and Polarization)
SMILE-II will be improved to SMIEL-III having > 10cm2 ( severaltimes better sensitivity of COMPTEL) in 2016.
In the long duration flight around the Polar cap, SMILE-III willmeasure ~10 Celestial objects, MeV-Cosmic Background and several
GRBs with polarization.