Post on 16-Aug-2020
PHYS 809PHYS 809--001001Special Lecture in Special Lecture in P i l Ph iP i l Ph iParticle PhysicsParticle Physics
Department of Physics and AstronomyTexas A&M Universityy
&Department of Physics
Kyungpook National University
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Course Description: Since March 2010 the LargeLarge HadronHadron ColliderCollider
What I am going to teach … Course Description: Since March 2010, the LargeLarge HadronHadron ColliderCollider(LHC) is delivering proton-proton collisions with a center-of-massenergy of 7 TeVTeV. Both CMS and ATLAS collaborations are reportingresults at low pT physics and re-discoveries of various StandardStandardpT p yModelModel (SM)(SM) particles (e.g., J/psi and Upsilon particles in 70s, W andZ bosons in 80s, top quark in 90’s). The re-discoveries helpunderstanding the detector performance and preparing discoveringnew physics at a TeV scale, which is one of the high priorityprograms at the LHC. Especially, supersymmetrysupersymmetry (SUSY)(SUSY) allows forthe construction of models of particle physics building up to the
dd ifi tiifi ti (GUT)(GUT) l d li ki t ll ii Thigrandgrand unificationunification (GUT)(GUT) scale and linking to earlyearly universeuniverse. Thiscourse is designed as an introductory course for graduate studentsto cover a broad spectrum of particle physics at the LHC, includingbasic concepts of the collider complex and experimental apparatusbasic concepts of the collider complex and experimental apparatusas well as how to probe physics beyond the Standard Model.
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http://faculty.physics.tamu.edu/kamon/teaching/phys809/http://faculty.physics.tamu.edu/kamon/teaching/phys809/
1) LHC The world’s largest accelerator
Key Words1) LHC … The world s largest accelerator2) TeV … Trillion (1012) electron-Volt (1eV = 1.6 X 10�19 J)3) SM … The current theory of particle physics4) SUSY A th f ti l h i ith d k4) SUSY … A new theory of particle physics with a dark
matter candidate5) GUT … Unification of three fundamental interactions)6) Early Universe … ~10-7 sec after Big Bang
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Textbooks:
Textbooks and GradeTextbooks:
Review articles and current literature will be provided. SinceSince mymylectureslectures covercover thethe onon goinggoing researchresearch programprogram atat thethe LHCLHC II willwill useuselectureslectures covercover thethe onon--goinggoing researchresearch programprogram atat thethe LHC,LHC, II willwill useusemymy researchresearch paperspapers along with contents in several populartextbooks:
1) “Introduction to High Energy Physics,” D. Perkins (Cambridge);2) “Particle Physics,” B.R. Martin and G. Shaw (Wiley);3) “Quarks & Leptons,” F. Halzen and A.D. Martin (Wiley);4) “Th Hi H ’ G id ” J F G i H E H b G K d S4) “The Higgs Hunter’s Guide,” J.F. Gunion, H.E. Haber, G. Kane, and S.
Dawson (Addison Wesley);5) “Weak Scale Suppersymmetry,” H. Baer and X. Tata (Cambridge)
Grade:
100% base on 4 homework assignments (Reports written in English)
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My Office: Room 220Contact Information
My Office: Room 220(Feel free to see me even without appointment!)
WCU Office: Room 201 (Ms. BoHwa Kim and Ms. JungEun Choi)
E-mail: kamon@tamu.edu
PleasePlease sendsend meme ee--mailmail fromfrom youryour accountaccount..SoSo II havehave youryour contactcontact informationinformation andandSoSo II havehave youryour contactcontact informationinformation andandkeepkeep youyou informedinformed..
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Any questions?Any questions?
Introduction toIntroduction toIntroduction to Introduction to IntroductionIntroduction
1)1) My CVMy CV2)2) My ResearchMy Researchhttp://faculty physics tamu edu/kamon/research/Cosmology at Colliders/http://faculty physics tamu edu/kamon/research/Cosmology at Colliders/http://faculty.physics.tamu.edu/kamon/research/Cosmology_at_Colliders/http://faculty.physics.tamu.edu/kamon/research/Cosmology_at_Colliders/http://faculty.physics.tamu.edu/kamon/research/LHCpheno/http://faculty.physics.tamu.edu/kamon/research/LHCpheno/
Phys. Lett. B 505 (2001) 161Phys. Lett. B 538 (2002) 121y ( )Phys. Lett. B 611 (2005) 223Phys. Lett. B 618 (2005) 182Eur. Phys. J. C46 (2006) 43Phys. Lett. B 639 (2006) 46Phys Lett B 649 (2007) 73Phys. Lett. B 649 (2007) 73Phys. Rev. Lett. 100 (2008) 231802Phys. Rev. D 79 (2009) 055002hep-ph/1008.3380, submitted to Phys. Rev. D.
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Elementary Schoole e y Sc oo
High SchoolTexas A&M University –Mitchell Institute for Fundamental Physics and Astronomy
Junior High School
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10
3
2
8
(USA near Chicago)(USA near Chicago)
Tevatron (proton-antiproton collider)
(USA, near Chicago)(USA, near Chicago)
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TevatronTevatron
6.3 km ringCenterCenter--ofof--mass energymass energy= 2 TeV
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CERNCERN(Switzerland near Geneva)
LHC (proton-proton collider)
(Switzerland, near Geneva)
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27 km ring
10
CenterCenter--ofof--mass energymass energy= 14 TeV
~
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[Research] Search for Dark Matter at LHC
a) What are we made of?b) Is the dark matter a new elementary particle?b) Is the dark matter a new elementary particle?c) how to detect the dark matterd) Interconnection between particle physics and cosmology
(earl ni erse)(early universe)
[Funding][Funding]a) US Department of Energy (DOE)b) National Research Foundation (NRF) of Korea
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���� What are we made of?What are we made of?�� Is the dark matter a new particle?Is the dark matter a new particle?
H t d t t th d k ttHow to detect the dark matterInterconnection between particle physics and cosmologygy
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What Are We Made Of?What Are We Made Of?
10 cm
14
10 cm
Standard ModelStandard Model12 l t ti l d 4 f d t l i t ti12 elementary particles and 4 fundamental interactions
gg �� WW GG
g’s (gluons) � string interaction
�’s (photons) � electromagnetic interaction
W’s (weak bosons) � weak interaction
G (graviton) � gravitational interaction
All masses in MeV.ANIMAL MASSES SCALE WITH PARTICLE MASSES
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What Is The Universe Made Of?What Is The Universe Made Of?[2] Earth [3] galaxy NGC 4414[1] Human
[4]
~17,000 parsecs in diameter (1 pc = 30.857×1015 m)
[5]
Dark Matter
[4]
Dark Energy
[5]
Dark Matter(23%)
Dark Energy(73%)
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23% Is Dark Matter23% Is Dark Matter3 El t3 El t3 Elements3 Elements
Is dark matter a Is dark matter a new particle?new particle?
Ordinary Matter
Can be explained by the SM17
Splitting ordinary matter and dark matter
Dark Matter in the UniverseDark Matter in the Universe1
Splitting ordinary matter and dark matter– Another Clear Evidence of Dark Matter –
(8/21/06)Ordinary Matter(NASA’s Chandra X
2
(NASA s Chandra XObservatory)
tim
e
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Approximately
February 9, 2008 Dark Particle Hunters
Dark Matter(Gravitational Lensing)
Approximatelythe same size asthe Milky Way
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Is Dark Matter a SM Particle?Is Dark Matter a SM Particle?Dark matter particles:Dark matter particles:(1) Weakly interacting(2) Neutral(3) Heavy … relativistically slowly moving
[A] Quarks, electron, muon, and tau cannot be dark matter,because they are interacting via strong and/or electromagneticforces. Neutrinos are too light.
What should we do?A new idea based on symmetry
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[Ref.] Symmetry in SMSymmetry in SM
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Supersymmetry (SUSY)Nature loves symmetry!Nature loves symmetry!Nature loves symmetry!Nature loves symmetry!
SM
D k M tt P ti lD k M tt P ti l
0�~Dark Matter ParticleDark Matter Particle
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1� SUSYNeutralNeutral--inoino ss--leptionleption ss--quarkquark
Wh t d f?What are we made of?Is the dark matter a new particle?
�� How to detect the dark matterHow to detect the dark matterHow to detect the dark matterHow to detect the dark matterInterconnection between particle physics and cosmology
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E 2
Collider and Physics MagicCollider and Physics MagicE = mc2
In proton-(anti-)proton collisions, top quarks as well as new heavyparticles (e g dark matter) can be createdparticles (e.g., dark matter) can be created.
Dark Particle Hunters 23
Fast pingFast ping--pong balls pong balls �� Slow steel ballsSlow steel balls
My DreamMy DreamPossible to create really heavy new particlesPossible to create really heavy new particles.
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My Wife’s DreamMy Wife’s Dream
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Recap: “TeV”, “Dark Matter”, “SM”, “SUSY”. Any questions?Any questions?
CERN, LHC, 4 Detectors
CMS
pp
GenevaGenevaAirportAirport
LHCb
p
ALICEATLASATLAS
The LHC at CERNCERN (known as European Organization for Nuclear Research in Geneva, Switzerland) provides the proton-proton (pp) collisions. The smashing power is 3.5 times larger than that of the Tevatron at Fermilab (Batavia, IL, USA).
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[Ref.] World Wide Web (WWW)Twenty year ago an event at CERN changed the worldTwenty year ago, an event at CERN changed the worldforever …
Tim Berners-Lee We learned Englishgfrom WWW.
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LHCLHC
27 km ring
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[LHC] Each proton can be accelerated up to 99 999999% of
Magnets, Magnets & MagnetsMagnets, Magnets & Magnets[LHC] Each proton can be accelerated up to 99.999999% ofspeed of light, using 1232 14.3m-long dipole magnets and8000 other types of magnets. Equivalently, we need11 200200 000000 000000 000000 ((11 22 )) 12 V b tt i f it11,,200200,,000000,,000000,,000000 ((11..22 )) 12-V car batteries for itsoperation.
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14,000 x mass of proton (14 TeV) = Collision Energy
Welcome to Physics CasinoWelcome to Physics Casino, p ( ) gy
Protons fly at 99.999999% of speed of light2808 = Bunches/Beam
100 billion (1011) = Protons/Bunch
7.5 m (25 ns)7.5 m (25 ns)
1414 TeVTeV ProtonProton--ProtonProton CollisionsCollisionsBunch Crossing 40 million (10Bunch Crossing 40 million (1066) Hz) Hz
Proton Collisions 1 billion (10Proton Collisions 1 billion (1099) Hz) Hz
One “discovery” event One “discovery” event inin
10,000,000,000,00010,000,000,000,000
Parton CollisionsParton Collisions
New Particles 1 Hz to 10 micro (10New Particles 1 Hz to 10 micro (10--55) Hz) Hz(Higgs, SUSY, ....) (Higgs, SUSY, ....)
10 trillion 10 trillion collisionscollisions30
LHC Now LHC Now –– “150 ns” Scheme“150 ns” Scheme� n trains (injections) of eachone train of m bunchesone train of m bunches � n trains (injections) of each
m bunches�� NN = n x m = Total number of
one train of m bunches
shifted by �3 x 25ns slots
one train of m bunches
shifted by �3 x 25ns slots�3
bunches� M = NN – n/4 = Number of
collisions in each of IP1 IP5collisions in each of IP1, IP5and IP8
-3 +3
� Example (NN = 48= 48):n = 12 & m = 4 � M = 45
4 & 12 � M 47
-3-3k
n = 4 & m = 12 � M = 47
� Add k bunches for ALICE m m m
at IP2. Typically k = ~ N/16
31NN can be ~2800 at a full strength of the LHC.can be ~2800 at a full strength of the LHC.
Aiming for 10Aiming for 103232 by End of 2010by End of 2010l k f ( k i h h i l i i )l k f ( k i h h i l i i )9 real weeks to go for pp (+1 or 2 weeks with a technical stop in it)
To reach ~400 bunches we would need steps of 2.7 MJ/week (48 bunches)9 real weeks to go for pp (+1 or 2 weeks with a technical stop in it)To reach ~400 bunches we would need steps of 2.7 MJ/week (48 bunches)
6 12 12 24 24 24 48 48 48 96 144
Commissioning trains.Complete crossingCommissioning trains.Complete crossing
2 shifts pilot HI commissioning2 shifts pilot HI commissioningp g
schemes start with 48b.
p gschemes start with 48b.
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384192 240 288 336??
??
??
HI run: to be discussedHI run: to be discussed 32
Luminosity ParametersLuminosity Parameters2
][Hz/cm104
231
T
2
����� *
b NkfL
Parameter Value now Realistic target Ratio
using �T =3.5 m , N=1011 , kb=35 , �*=3.5 m
gfor 2011
N 9 1010 11 1010 11/9 = 1.22
�* 3.5 m 2 m 3.5/2 = 1.75
��T ~4…7 μm 3.75 μm 4…7 / 3.75 = 1 … 2� T μ μ
kb 35 ~800 800/35 = 23 !!
The only parameter which is still far away from a “realistic 2011 target”is the number of bunches � first priority
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AnalysisAnalysisHHST
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DetectorDetector –– Where?Where?
Prof. Steve Hawking, visiting the CMSexperimental site.
79 ft high x 173 ft long79 ft high x 173 ft longLowering the 1st heavy element of theCMS detector
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DetectorDetector –– How Big?How Big?
Me!Me!
21 m x 15 m x 15 m, 12,500 ton36
“HEP” Equation“HEP” EquationN b = (cross section) x (luminosity) x (acceptance)
� � ALddALNTT
�
����
Nobs = (cross section) x (luminosity) x (acceptance)
� � ALdtdtALN �
����� ��
00
��
1 cm2 1 cm-2
1 barn = 10-24 cm2 1 b-1
1 pb = 10-12 b 1 pb-1
(inverse pico barn)
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“Ph.D.” View“Ph.D.” View
NT ��
�� exptheory ��ALdt
T
�
����
��0
e peo y
Experimental Ph.D.Theory Ph.D. Accelerator Ph.D.
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““DimuonDimuon” View” View
� ALdtXBrXppNT
�
����
���� ��� )()(
����0
Total efficiency for accepting two muonsin any pp collision :
Ageom() * Akin() * �trig * (�ID)2
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ReRe--Discovery : Discovery : DimuonDimuon ResonancesResonances
1974 J�� � +–
1977 � � +–
LHC is powerful enoughto re-discover those
1983 Z� +–
particles in 4 months.
983 �
(~80 x 10(~80 x 1099 pppp collisions)collisions)
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pppp
M(M() at CDF, D0, and CMS) at CDF, D0, and CMS“Trigger” does matter.
Rare BRare B
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[Ref.] “Resonance” Particles[Ref.] “Resonance” Particles
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Mesons vs. QuarksMesons vs. Quarks
XBrJX PC
nDescriptioQuark
)( � ��
dduu2
10)28.055.4(1)770(
nDescriptio50 �
�� ����
dduu10)1.30.9(1)782(
250 �
�� ����
�
ss10)19.087.2(1)1020(2
)()(40 �� ����
bbccJ
)%05.048.2(1)S1()%06.093.5(1)S1(/
� �
��
���
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[Ref.] Parity Operation[Ref.] Parity Operation
)()()()()(
)()(:Parity
PrrPrP
z,y,xz,y,x
��
������ ���
����
)()( rrP �� ��
112 ��!�" PP
0)-spinforscalar-psudo(e.g.,odd""10)-spinforscalar(e.g.,even""1
11
����
��!�"
PP
PP
proton 1�#� PPPP duu
)pp( g ,
bosonantiboson
fermionantiferimion
p
�
�
����
PPPP
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Parity of TwoParity of Two--Particle SystemParticle System�)1()( PPffP )1()( �� ff PPffP
Exercise 1: Find the parity of a system of two spin-0ti lparticles.
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Parity of ThreeParity of Three--Particle SystemParticle System
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Natural UnitsNatural UnitsUnits of Mass, Momentum, Energy are eV/c2, eV/c, eV, where 1 eV = 1.6 x 10-19 J
In physics, natural units are physical units of measurementdefined in such a way that certain selected universalphysical constants are normalized to unity; that is, theirnumerical value becomes exactly 1.
In particle physics, the phrase" t l it " ll"natural units" generally means:
1B ��� kc �
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B
[Q] ?
![Q] ?[A]
[Q] ?[Q] ?[A] A & M .
[Q] ?[A]
[Q] .?
[A] 1[A] 1
[Q] ???[ ][A] 1 ?
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[Q] Where are you from?
Be Careful at Passport Control![Q] Where are you from?[A] Japan
[Q] Wh t i j b?[Q] What is your job?[A] Faculty at Texas A&M
[Q] Oh, Aggies! What do you teach?[A] Physics
[Q] Oh, I took a physic course. Then whatis the value of speed of light?
[A] 1[A] 1
[Q] What???[ ][A] What is wrong with “1”, Sir?
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Wh t d f?What are we made of?Is the dark matter a new particle?How to detect the dark matter
�� Interconnection between particle Interconnection between particle physics and cosmologyphysics and cosmologyp y gyp y gy
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CBS comedy “Big Bang Theory”CBS comedy “Big Bang Theory”(Season 1 Episode 15)(Season 1 Episode 15)
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International WorkshopsInternational WorkshopsInterconnection between Particle Physics and CosmologyInterconnection between Particle Physics and CosmologyInterconnection between Particle Physics and CosmologyInterconnection between Particle Physics and Cosmology
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[Example] Top Quark Discovery in 199543 did t i 3 443 did t i 3 4 10101212 lli illi i43 candidates in 3.443 candidates in 3.4 x 10101212 collisionscollisions
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Dark Matter Discovery in 20**Dark Matter Discovery in 20**(10 10 000) 1012 C lli i(10-10,000) x 1012 Collisions
p
DM
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1) LHC The world’s largest accelerator
Recap1) LHC … The world s largest accelerator2) TeV … Trillion (1012) electron-Volt (1eV = 1.6 X 10�19 J)3) SM … The current theory of particle physics4) SUSY A th f ti l h i ith d k4) SUSY … A new theory of particle physics with a dark
matter candidate5) GUT … Unification of three fundamental interactions)6) Early Universe … ~10-7 sec after Big Bang
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REMARKSREMARKSYOU relax and enjoy the YOU relax and enjoy the
iitopics.topics.
[ 4%] Can be explained by the SM[23%] New particle(s)? Expected to be[23%] New particle(s)? Expected to be studied at the LHC[73%] Still major puzzle[73%] Still major puzzle
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Detectors in Movies [Part 1]
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Detectors in Movies [Part 2]
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Dark Particle Hunters
Solution will be posted at URL:http://faculty.physics.tamu.edu/kamon/research/talk/
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Backup
Snapshots of Discoveries
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Observation of an e–e+ pairin �0�� e–e+ decay mode
e+
e–
–n �
�
�–
p
n�0
�
p
�–
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Liquid-hydrogen bubble-chamber photograph of antiprotoncolliding with a proton, producing $ and anti-$.
_ __u d s%&=2.6x10�10 s
_ __
d s s% =1 64x10�10 s
___
Elementary Particles
%$=1.64x10 s
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p + p � 8�’s–
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The first '– event (Barnes et al., 1964) in K– + p interaction.
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A Neutral Current (Z0 Boson)ReactionReaction
Z0
((
Feynman Diagrams
(
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A Neutral Current (Z0 Boson)ReactionReaction
Z0
((
Feynman Diagrams
(
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A Neutral Current (Z0 Boson)
Feynman Diagrams 68
Particle ClassificationParticle Classification
The Quark IdeaThe Quark Idea
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Elementary Particles Elementary Particles –– Building Building BlocksBlocks
Hadrons, MesonsScale
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AntiAnti--MattersMatters
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