430 likes | 730 Vues
LHAASO @ TeV 物理工作组会议. 曹臻, IHEP ,北京 泰达学院,塘沽, 2009. CRs at TeV. Ultra High Energy Cosmic Rays GZK cut-off related physics. TeV γ ray astronomy. “conventional” model. Propagation effects Fermi acceleration Astro-accelerators?. Out line. TeV γ ray astronomy (introduction)
E N D
LHAASO @ TeV 物理工作组会议 曹臻,IHEP,北京 泰达学院,塘沽,2009
CRs at TeV Ultra High Energy Cosmic Rays GZK cut-off related physics TeV γray astronomy
“conventional” model • Propagation effects • Fermi acceleration • Astro-accelerators?
Out line • TeV γray astronomy (introduction) • CR observational focus @ TeV region • What can LHAASO contribute • Status of the project
All interesting objects • PWN: Crab, Vela … • SNR: RXJ1713, Cas A … • XRB: Cygnus X-1, LS 5039 • ….
Models for γray emission • Electron origin model: synchrotron+IC • Synchrotron photons could be scattered again by electrons (SSC model) • Multi wavelength observation ??? lg10 (E/eV)
Difficulties:RXJ1713.7-3946 Leptonic model ASCA data: (synchrotron X rays) • Fine structures in the radiation morphology points to B>100µG • If leptonic, X/TeV ratio requires B~10µG (with sIC/sSynca B-2 ) Hadronic model favored Hadronic model Still pending: • Hadronic model to be confirmed • Occurence of such objects? (cf scan)
We are looking for good astro-accelerator lab in the sky SN1006: γ ray observation still needs to be improved
The other example: PSR B1259-63 • XRB: TeV emission occurs as the compact object is far away from the Be Star?! Could be an effect of absorption by photons from the B-star, however, is it really against the SSC model? LSI+61 303 is Another example which does not Show difference Of spectral index
LS I +61 303 Radio Outbursts near apastron, ~4yr modulation TeV Activity detected by MAGIC/VERITAS around apastron passage High X-ray activity throughout orbit (strongest at apastron, secondary near periastron) Be Star BH/NS P~26.5 day Earth By Andy Smith at TeVPA 2009, SLAC
All Data 2006-2009 By Andy Smith at TeVPA 2009, SLAC Apastron Preliminary Phases 0.9-0.5 Phases 0.5-0.9 ~4.5σ(pre-trial) 10σ Preliminary Preliminary
Many varying sources > 0.05ICrab at base states ≥10 ICrab during flares Very far sources: EBL absorption is severe above 10TeV
γastronomy: Mrk421flares 5.9σ 2006/07-08 2006/11 2006/10 2006/09 2006/09 • 2006/7~8:5.9σ • 2007:very calm • 2008/1~4:~5.7σ ASM of RXTE ARGO RXTE
Mrk421single flare: 10ICrab • ARGO has seen a 4σeffect for 2008/05/02 transition. Whipple
ARGO RXTE/ASM 2008 June 11-13 day163-165 Multi-wave-length Observation of Flares of Mrk421 For LHAASO, only 1 minute is needed
Multi-wavelength observation:does SSC model work perfectly? More sensitive observation with much larger exposure is essential in TeV regime VERITAS Collaboration
There are many samples “Personality” seems very strong between transient events and objects Many “guesses” with lacks of strong evidences. Strong demanding on population study: full sky survey!
Or some big pieces “dropped” into BH/NS and triggered an outburst??
TeV γRay Astronomy • γRay Burst Search & Exotic phenomena • Yet successfully observed any GRB • Dark matter search • Quantum gravity effect search
Focus of CR observation @ TeV • Knee and second knee • Absolute energy scale at UHECR experiments • Forward region behavior • μ content in a shower
UHECR Research (experiment) access? YBJ
What can LHAASO help? • All sky source survey
Leptonic model ? Hadronic model Scientific Problems and Possible Solutions • TeVγray observation has an opportunity of finding CR origin: 80+ sources discovered • 50+ galactic sources: γat high energy (>30TeV) is crucial (high sensitivity and high energy resolution) • All-sky survey forγsource population is necessary (full duty cycle, wide FOV and sufficient sensitivity) • PeV CR spectra of individual composition • Bridge between space/balloon borne measurements and ground based UHECR measurements • Searching for Dark Matter galactic sub-structures
Charge Particle Array μdetector Array Water C Array Wide FOV C-Telescope Array & Core Detector Array LHAASO Project: γastronomy and origin of CR Large High Altitude Air Shower Observatory
? Forγastronomy ARGO
Proton Iron For Proton and Helium: • 1.5 m spacing • Nb>100 , any 5 (> 30 GeV) For Iron: • 3.75m spacing • Nb>100 , any 21 ( > 30 GeV) Resolution for light and heavy compositionμ-content, Xmax and HE (>30TeV) shower particles
The keys are to lower threshold, making connections with direct measurements & measure spectra up to 100PeV
A bridge between balloon measurements and ground base UHECR experimentcovering both “knees” with absolute energy scale
We are here Second knee knee An unique location
Prototyping • R/D budget: ~$1M • Detector unit prototype @ IHEP
ARGO Hall On Site Prototype Exp. • 1% of the final configuration of LHAASO
预先研究进展 • 1%规模实验计划
CR Energy Spectrum (160k events) resolution < 10% With bias<3% Core resolution <1m From S. P. SWORDY, Space Science Reviews 99: 85–94, 2001.
Conclusion • √s ~ 1TeV for CRs is a very important region associated with a transition from galactic origins to extra-galactic origins • Elab~ 1TeV for γrays is one of the most active astro-particle physics fields. Many sources have been discovered in the last two decades • LHAASO will boost all sky source survey power for population study, also have strong power for galactic CR source discovery • Currently, the R/D for the project goes smoothly