スライド 1 - (CTA) Japan
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Transcript スライド 1 - (CTA) Japan
井岡
邦仁
(KEK)
共同研究者： 川中宣太 (KEK)
Positron excess above the predicted secondary
Positron
Excess
⇒ Primary sources
- Dark matter?
- Astrophysical?
⇒ Many papers
>400
Solar
modulation
Expected
Secondary
Adriani+ 08
Jul 06 - Feb 08
151672 e-, 9430 e+
An Excess also in (e++e-) Spectrum
ATIC/PPB-BETS
Peak+Cutoff
~600GeV DM?
Fermi
Smooth E-3
No peak
Aug 08 – Jan 09
4M eAbdo+ 09
有効面積大
5×104 m2 @1TeV
~8.5×107 m2 sr s
(2004-2007)
◉Consistent with
Fermi
◉No ATIC peak
(but not rule out)
◉Steep at >1TeV
Aharonian+ 09
Primary sources
視野・台数増 ⇒ 有効面積大 ⇒ より高エネルギー
計画
CTA
2013~
AMS-02
2010~
CALET
2013~
e/p
Exposure
(m2 sr s)
??
~103-4?
~109
(1 yr)
1~1,000
~2.5%
@100 GeV
~104
(×102 by
TRD)
3×106
(1 yr)
1~10,000
~2%
(>100 GeV)
~105
4×106
(1 yr)
帯域
(GeV)
10~15,000
DE/E
注: シミュレーションでproton backgroundの評価
⇒ E~15%不定性 ⇒ w/ LHCf ?
r(proton)
~1eV/cm3
~超新星残骸
e-2.7
0903.1987
r(electron)
~10-2eV/cm3
r(positron)
~10-3eV/cm3
~ 0.1% of p
起源が不明
ガンマ線、電波
e± cooling
We are here
Our galaxy
e± lose energy (cool)
via inverse Compton
and synchroton
ecut
1
4 T c B
~ , b
U
2
bt
3mc 2 8
2
Positron source
d<~1kpc
Decay
Annihilation
DM
e
e
DM
DM
e
Q ~ n2
Ecut ~ mDM
<v>~3x10-24cm3/s
>3x10-26cm3/s
boost factor ~100
c
Q~n
Ecut ~ mDM/2
tdecay~1026sec (>H-1)
郡さんのトーク
Pulsar
mQSO
SNR
GRB
Shen 70; Aharonian+ 95;
Atoyan et al. 95; Chi+ 96;
Zhang & Cheng 01;
Grimani 07; Yuksel+ 08;
Buesching+ 08;
Hooper+ 08; Profumo 08;
Malyshev+ 09; Grasso+ 09
Kawanaka, KI & Nojiri 09;
Shen & Berkey 68;
Pohl & Esposito 98;
Kobayashi+ 04;
Shaviv+ 09; Hu+ 09;
Fujita+KI 09; Blasi 09;
Blasi & Serpico 09;
Mertsch & Sarkar 09;
Biermann+ 09
Propagatio
Proton Comtami. n
Fazely+ 09; Schubnell 09
Delahaye+ 08;
Heinz &
Sunyaev
02
KI 08
Cosmic-ray Nuclei energy
10-3 x 1050erg/SN
~ (1sec pulsar)/SN
~ 1050erg/103SN
Power-law Spectrum
ee
B
dEe
de e
Burst-like
injection
e
2
e
ee
2
2
f t,ee , x K ee f
b
e
e f q t,ee , x
t
ee
Diffusion
b ~ 1016 GeV -1s1
Energy loss by
IC & synchro.
ee
28
2 1
K ee ~ 5.8 10 cm s 1
4GeV
Injection
13
← B/C ratio
e Power law spectrum
For a single burst with q
q0ee
2 d d
f 3 2 3 1 btee e
1
ddiff
e
2
diff
ddiff t,ee ~ 2K ee t
12
Atoyan+ 95, Shen 70
ecut ~
bt
We can fit the PAMELA data well
KI 08
d=1kpc
(a)
0.9d50 erg
2d5 yr
=2.5
(b) Harder
0.8d50 erg
5.6d5 yr
=1.8
(c) Older
3d50 erg
3d6 yr
=1.8
ATIC/PPB-BETS & Fermi/HESS
KI 08
d=1kpc
(a)
0.9d50 erg
2d5 yr
=2.5
(b) Harder
0.8d50 erg
5.6d5 yr
=1.8
(c) Older
3d50 erg
3d6 yr
=1.8
Due to cooling
ATIC peak
HESS cutoff
Independent
of initial emax
KI 08
t cool e
1
e
e
e e
2
Q
(
t
)
r
2
0 e
F
(
t
,
)
d
t
1
b
t
exp
e
e
3
/
2
3
2
r
r
diff
dif
0
t
Case 1: pulsar-type decay
E
t ot
Q
(
t
)
L
0
sp in d o wn
2
1
t
/0
0
t t
t0
Case 2: exponential decay
E
ln
4 t
ln
4
to
t
Q
(
t
)
exp
0
0
0
t
t
t0
Cutoff width Decut
CTA
Dt~105yr
e-t decay
Cutoff width
Kawanaka+ 09
Dt~105yr
t-2 decay
Dt~104yr
t-2 decay
CTA
Kobayashi+ 04
現在見えているとは
限らない。t<104-5y
tcool~105yr @TeV
tSN~105yr @<kpc
分散
CTA
Kawanaka+ 09
A single source ⇒ A relatively large anisotropy
I max I min
I max I min
3K f
cf
3d
~
@ e e ~ e max
2 ct
Challenging
DM clump
KI 08; Mao & Shen 72
Fermi~6×106 erg sr s
CTA~109 erg sr s
Anti-proton
fraction
Fujita, Kohri, Yamazaki, KI 09
Blasi+ 09
SNR model:
pp → → e+,e(w/ ISM/DC)
Inevitably
⇒ anti-proton
excess above
~100 GeV
⇒ AMS-02
e-, e+, , anti-p
Moon shadow
の位置が異なる
⇒ 分離可能
CTA:
150GeV~3TeV
detection<5hr
月の散乱光が
background
Colin+ 09
Hadronic models ⇒ Secondary Nuclei Excesses
Boron-to-carbon ratio
Titanium-to-iron ratio
Z=22
Z=5
Mertsch and Sarkar 09
Z~7-40 with DZ/Z~5% for 10~1000TeV
Fe
balloon/space
shower
CTA
PHYS-WP-heavy nuclei
Source #
~100
1-10TeV e
⇒ IC
⇒ ~TeV
観測から
電子ソース
E>1048erg
~0.5 Crab
@2kpc
閉じ込め~105yr
N∝R2∝F-1
点源（カロリメトリッ
⇔ 柴田さん：diffuse
Fmin(電子ソース)
＠20kpc
閉じ込め~10４yr
N∝R2∝F-1
~PSR J1826-1334
閉じ込め中
エネルギーが
大きい場合
Diffusion
coefficient
などにもよる
電子・陽電子宇宙線の起源
Astrophysical? Dark Matter?
直接観測は今後進展
有効面積： CTA >> AMS-02, CALET
⇒ >TeV: Discreteness, Injection History
非等方性: Single or Multiple
pbar, Heavy: Hadronic or Leptonic
TeV電子ソース ⇒ TeVガンマ線ソース
閉じ込め時間は短い? or DM?
サーベイ、広がったソース
PHYS-WP
計23人
Dark Matter / Fund. Physics 6
6
EBL / Cosmology
AGNs
9
CR / Clusters / Starbursts
8
MQ / Binaries
3
CR / SNRs / Mol. Clouds
11
PWNe
3
Pulsars / Glob. Clusters
3
MW / Transients / GRBs
7
Surveys / Sub-arrays
1
Extended / Diffuse Srcs.
4
Intensity Interferometry
0
DC Light / CR composition
1
◉ まずは、論文を書くとき
CTAについて議論
◉ CTA-Japanは後発
◉ 長期的には組織的に
力を合わせたほうがいい
◉ アイデアが必要
- 論文を全員に回覧
- CTA-Japan Paperを
重要なものに関しては書く
Task A, Bの日本版
-…