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Journal Club
• 매주 목요일– 3:45-4:00 다과회– 4:00-4:45 발표 및 토론회
• 2009 년 1 월 22 일 – HEP 101• 2009 년 1 월 29 일 – 대칭성• 2009 년 2 월 5 일 - 검출기• …..
용평 국제입자물리학술대회• 제목 : APCTP 2009 YongPyong (YongPyong Astro-Particle and Conformal Topical Physic
s 2009)• 일시 : 2008 년 2 월 23~27 일• 장소 : 강원도 용평 리조트• 내용 : 세계 3 대 입자물리 겨울 학회
– 북미 (Aspen), 유럽 (Moriond), 아태 ( 용평 )– 핵입자물리연구회 봄미팅과 연계– Plenary 세션 & Parallel ( 끈이론 , 현상론 , 실험 / 컴퓨팅 )
• 주최 : 아태이론물리센터 , 서강대 양자시공간연구센터 , 고등과학원 , KISTI
• 홈페이지 : hep.kisti.re.kr
High Energy Physics 101
Kihyeon Cho
January 22, 2009
People have long asked,
• What is world made of? and
• What holds it together?
• In Ancient time
What is world made of?
water
fire
earth
air
What is World Made of?
Standard Model
• t, b, c are heavier than other quarks - heavy flavor quarks
• W, Z, top are stand out from the rest.
Matter
• Hadron (Quark) - size– Baryon (qqq): proton, neutron– Meson (q qbar): pion, kaon
• Lepton – no size– Point particle
How to know any of this?(Testing Theory)
• Example
– Light bulb (Source)– Tennis ball (target)– Eye (detector)
• Accelerators solve two problems:
– High energy gives small wavelength to detect small particles. (Lambda = h /p )
– The high energy create the massive particles that the physicist want to study.(E=mc^2)
How to detect?
Accelerator design
• Shapes– Linacs (SLAC)– Synchrotrons (Fermilab)
• Collision types– Fixed target (E687, FOCUS)– Colliding beams (CDF, Belle, BTeV) => CM = 1TeV+1TeV => 2TeV
High Energy Experiment
Fixed target vs Colliding beams
(total energy)2-(total momentum)2 = invariant in all frames of reference
Assume that 800GeV(Ebeam) proton collides in a fixed target(proton).
Center of mom. frame Laboraroty frame
Total energy: ECM Ebeam+mp
Total momentum: 0 Pbeam
Invariant: ECM2 (Ebeam+mp
)2-Pbeam2
E = [ 2(mp2+Ebeammp) ]1/2 = 38.8GeV
We are enough to 19.4GeV+19.4GeV proton beams in collider !!!Question: What’s the advantage of a fixed target experiment?
The Fermi National Accelerator Laboratory
Where is Fermilab?
• 20 mile west of Chicago
• U.S.A
Fermilab
Fermi National Accelerator Laboratory
Highest Energy Accelerator in theWorld
Energy Frontier: CDF, D0 Search for New Physics (Higgs, SUSY, quark composites,…
Precision Frontier: charm, kaon, neutrino physics(FOCUS, KTeV, NUMI/MINOS,BOONE,…etc.
Connection to Cosmology: Sloan Digital sky survey, Pierre Auger,…
Largest HEP Laboratory in USA
2200 employees2300 users (researchers from univ.)Budget is >$300 million
Overview of Fermilab
Main Injectorand Recycler
p source
Booster
CDF
D0
Fixed Target
Experiment
Tevatron Run 1 (1992-1996)
Protons
H source (18 KeV) → Cockcroft Walton accelerator (750 KeV) → Linac (400 MeV) → Booster (8 GeV) → Main Ring (150 GeV) → Tevatron (900 GeV)
Antiprotons Main Ring (120 GeV) → Antiproton Source (Ni) → Debuncher (8 GeV) Accumulator (8 GeV) → Main Ring (150 GeV) → Tevatron (900 GeV)
Tevatron Run II (2001 – 2010)
• Main Injector (150 GeV proton storage ring) replaces Main Ring
• Pbar improved – Cooling system – a new permanent
magnet recycler
• Increased number of p and pbar bunches (6 36 100 )
What holds it together?(The four interactions)
Masses of Fundamental Particles
• t, b, c are heavier than other quarks - heavy flavor quarks
• W, Z, top are stand out from the rest.
Electromagnetic interactions w/ atoms
Weak Electro-magnetic
Strong
Range 1/Mw Infinitive 1F=1/m
Typical Lifetime
(sec)
10^-12 or longer
10^-20~10^-16
10^-23
Typical Cross section(m
b)
10^-11 10^-3 10
TypicalCoupling
10^-6 10^-2 1
Summary of interactions
pp 0 pppp
References
• B.G Cheon’s Summer School (2002)• S.H Yang’s Colloquium (2001)• PDG home page (http://pdg.lbl.gov). K. Cho’s lecture (2004.9.20)