TibetIII (2003-)观测站西藏羊八井， 海拔 4300m （大气深度 606g/cm2)

现有阵列 :50,400 m2 闪烁体探测器 :0.5 m2 x 789 个其中： 快时间光电倍增管761 个，动态范围： 0 － 15 个粒子，时间分辨 0.8ns

大动态光电倍增管277 个，动态范围： 15 － 500 个粒子Energy resolution:10 TeV ~+70%-40% 100 TeV ~+40%-30%Angular resolution: 10TeV:0.5o

100TeV:0.2o

TibetIII (2003-)观测站西藏羊八井， 海拔 4300m （大气深度 606g/cm2)

现有阵列 :50,400 m2 闪烁体探测器 :0.5 m2 x 789 个其中： 快时间光电倍增管761 个，动态范围： 0 － 15 个粒子，时间分辨 0.8ns

大动态光电倍增管277 个，动态范围： 15 － 500 个粒子Energy resolution:10 TeV ~+70%-40% 100 TeV ~+40%-30%Angular resolution: 10TeV:0.5o

100TeV:0.2o

优势：高海拔

全天候，

宽视场

缺点：不能有效区分宇宙线

强子与电磁成分

Mrk501 ， 1997

TeV 能区伽马点源的观测 :Crab,Mrk421,Mrk501

Crab （ 6.3σ ）

MrK421 高态爆发， 2000&2001 (6.9σ)

All Sky Significance map

Solid line--all sky;Dashed line-gaus fit;Dotted line-without Mrk421 and Crab;Dot-dashed line-without Mrk421,Crab and MGRO J2019+37;

MGRO J2019+37

—Smooth radius is optimal angular resolution(0.99 °) thinking about the extension 0.32 ° of MGRO J2019+37

HEGRA J2032+4130MGRO J2031+41

MILAGRO C1

Mrk421

Crab

中日数据间接寻找暗物质湮灭信号湮灭截面

暗物质质量

中日数据间接寻找暗物质湮灭信号湮灭截面

暗物质质量

灵敏度不够！

Preliminary results on γ/e emission at 100TeV without having MUON detector

Upper ： Hints of 100TeV γ/e emission?

Tibet-MUON will give an answer, which is due to contribute to origin problem of CRs.

Lower: γ ray observationby famous sateliteexperiment EGRETat GeV energy.

(Zhaoyang Feng et al, ICRC2009)

Middle : EAS-1000 prototypearray from 100TeV to 10 PeV.

Preliminary results on γ/e emission at 100TeV without having MUON detector

Upper ： Hints of 100TeV γ/e emission?

Tibet-MUON will give answer and making important contribution to CRs research.

Lower: γ ray observationby famous sateliteexperiment EGRETat GeV energy.

(Zhaoyang Feng et al, ICRC2009)

Middle : EAS-1000 prototypearray from 100TeV to 10 PeV.

灵敏度不够！

排除 CR 本底的两种办法：横向分布和 μ 子数

100TeV 伽马射线簇射在 ybj 高度 100TeV 质子簇射在 ybj 高度

分辨一：

横向分布差别

分辨二：

缪子数差别

Tibet MD ： 10,000m2 underground Muon Detector 10-100TeV 能区世界上最灵敏的探测器

MD array --- 12 x 16 =192 muon detectors (~10,000 m2) --- 2.5m underground (~515g/cm2, ~19X0)

Each muon detector --- Water pool, made of concrete --- 7.2m x 7.2m x 1.5m depth 　 --- White waterproof surface --- 20” inch PMT x 2 (HAMAMATSU R3600)

Tibet MD ： 10,000m2 underground Muon Detector 10-100TeV 能区世界上最灵敏的探测器

MD array --- 12 x 16 =192 muon detectors (~10,000 m2) --- 2.5m underground (~515g/cm2, ~19X0)

Each muon detector --- Water pool, made of concrete --- 7.2m x 7.2m x 1.5m depth 　 --- White waterproof surface --- 20” inch PMT x 2 (HAMAMATSU R3600)

Inside view of MD prototype

88

:Sum of particle density by all scintillation det.

Shower Size （ a measure of energy ）

NPE :Sum of photoelectrons by all muon det.

the number of muons in air showers

E: 1.9 10 100 1000 TeV

8

Number of muons vs. Shower Size (Simulation)

Survival Efficiency (Simulation)

Energy 1.9TeV 10 TeV 100 TeV

NPE cut value

10PEs ~30 PEs ~910 PEs

BG rejection 95.4% ~99.7% >~99.99%

survival 59% ~61% ~99%

Sensitivity2.8 times improved

~11 times improved

BG free

5 or 10 ev. sensitivity to Point-like Gamma-ray Source 10-100TeV 能区世界上最灵敏的探测器

Background free10 gamma-ray eventssensitivity

A&A ， 464(2007)235-243

强子模型

SNR RXJ1713.7-3946 已有的多波段观测 + 100TeVγ 射线观测有助于确定宇宙线强子源

极大地增强了我们对宇宙线强子源的认识，有望回答宇宙线起源的问题

宇宙线轻子起源与强子起源，多波段联合观察

Indirect Detection of DM at 10TeV region

In a model independent way, χχ-> e+ e- , Natural Scale: <σv> = 3*10-26cm-3s-1 Einasto distribution, only considering the main halo Considering transportation （ GALPROP ）

FOV of YBJ

-180o180o

-90o

90o

Background and signal

Simulation study and data selection Full simulation of Tibet III and MD for CRs and electron

Data selection to get maximum S/B ratio ：

Theta<25o （ secTheta<1.1)

R<50m

Performace@10TeV ：

Energy Resolution ： -30%-+50%

Angular Resolution: 0. 5o

Simulation study and data selection Full simulation of Tibet III and MD for CRs and electron

Data selection to get maximum S/B ratio ：

Theta<25o （ secTheta<1.1)

R<50m

Performace@10TeV ：

Energy Resolution ： -30%-+50%

Angular Resolution: 0. 5o

Simulation study and data selection Full simulation of Tibet III and MD for CRs and electron

Data selection to get maximum S/B ratio ：

Theta<25o （ secTheta<1.1)

R<50m

Performace@10TeV ：

Energy Resolution ： -30%-+50%

Angular Resolution: 0. 5o

Event number by 1yr operation

10TeV 100TeV

Sensitivity to diffuse electron

暗物质间接探测灵敏度：Sensitivity for diffuse electron

vs electron fluxes from DM annihilation

e+e- pair production between CR s and radiation BKG => knee

ApJ 700:L170–L173, 2009 August 1; (astro-ph/0901.1520)

=> electron, positron excesses

ApJ 700:L170–L173, 2009 August 1; (astro-ph/0901.1520)

Pulsar Production of e+e-arXiv:0812.4457

Potential power in detecting the electrons from nearby pulsar

Summary Tibet ASγ Experiment has been successfully operated since 1989 and fruitful results have been obtained.

5 out of 12 MUON detectors are under construction in 2010. TibetIII-MD is expected to resume data taking in 2011. Sensitivity of ASγ experiment for observing the γ ray point source will beImproved by about a factor of 10 at several tens of TeV.

e+ e- from DM annihilation could be detected in 10TeV region by TibetIII+MD, If it follows the DM models used toexplain the ATIC and PAMELA excess.

Tibet III-MD will be sensitive in testing the models related to the astrophysics origin of e+/e- excesses

Advances in Space Research,Volume 27, Issue 4,2001, 653-658

Pulsar Production of e+e-

Survival efficiency

Pollution of CRs and diffuse γ

• Systematic error of cosmic rays survival efficiency

----Calibrated by Crab and Moon Shadow

Galactic and extra-Galactic diffuse γ rays at 10TeV region

----Detailed consideration, other experiments, theoretic calculation

蟹状星云一年观测预期事例数ECR ： 4.0 5.0 7.0 11.1 19 39 80 184 348 900 TeV

Eγ ： 1.9 2.4 3.5 5.6 9.8 20 39 89 210 550 TeV

Sensitivity to DM electron

Constrain to e+e- cross section

TibetIII+MD （ 5pool)+Einasto

P, He by Tibet hybrid Experiment (Phys. Lett. B, 632, 58 (2006))

Primary Proton spectrum Primary Helium spectrum (All - (P+He)) /All

1) Our results shows that the main component responsible for the knee structure of the all particle spectrum is heavier than helium nuclei.

２） The absolute fluxes of protons and helium nuclei are derived within 30% systematic errors depending on the hadronic interaction models.

GeV-TeV 伽马射线源观测Fermi 卫星发射后前 11 个月观测到的 1451 个点源（ 100MeV-100GeV)

106 个 TeV point Source

（ 61 gal + 45 extra-gal, up to 2010/11/11 ）

宇宙线起源之谜

“ 膝”区（ 4PeV ）以下是河内起源？

1011

能量

103

0流

强

河外？

主要是原子核： P ， He ，… , Fe,…

也有：， e±

还有： γ ， ν

非热能谱

dN/dE∝E-α

各向同性的分布

一些能区有微弱各向异性

P

1912-, Hess ，但• 哪里产生？• 如何加速？

CR+photon->CR+(e+e-)• CR knee has a energy of 4PeV, and is related

mainly with proton and Helium.• Many observation suggests that the major

component is He. • 4PeV energy to He corresponds to a Lorentz factor

of 106, just the right value for (e+e-) pair production when interacting with 5000Ko (~1eV) background photon and can produce e+/e- at ~500GeV!

• The energy flow of ATIC excess electron is 10-4

GeV/cm2sSr, between 80GeV- 900GeV, as same as the energy loss of CRs assuming that the cosmic rays change their spectrum indices from -2.7 to -3.1 above ~ PeV;