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Intro to Particle and Nuclear Physics and the Long Island Gold Rush. Steven Manly Univ. of Rochester REU seminar June 1, 2005 [email protected]. Inquiring minds want to know. Yo! What holds it together?. Fermi National Accelerator Laboratory (near Chicago). CDF. Minos. - PowerPoint PPT Presentation
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Intro to Particle and Nuclear
Physics and the Long Island Gold
Rush
Steven ManlyUniv. of Rochester
REU seminarJune 1, 2005
Inquiring minds want to know ...Inquiring minds want to know ...
Yo! What holds it together?Yo! What holds it together?
Fermi National Accelerator Fermi National Accelerator Laboratory (near Chicago)Laboratory (near Chicago)
CDFCDF MinosMinos
Stanford Linear Stanford Linear Accelerator CenterAccelerator Center
Event display from the SLD Event display from the SLD experiment at SLACexperiment at SLAC
What forces exist in nature?
What is a force?
How do forces change with energy or temperature?
How has the universe evolved?
How do they interact?
Force Source Range StrengthGravitation mass infinite 10-39
Electromagnetism Electriccharge
infinite 10-2
Strong nuclear Colorcharge
10-15 m 1
Weak nuclear Weakcharge
10-18 m 10-5
quarks leptonsGauge bosons
u c t
d s b
e
e
W, Z, g, Gg
Hadrons
Baryons qqq qq mesons
p = uud
n = udd
K = us or us
= ud or ud
Strong interaction
nuclei
e
atomsElectromagnetic
interaction
Mini-Ph.D. – Quantum Mechanics 101 Mini-Ph.D. – Quantum Mechanics 101
Lesson 1:Lesson 1:
Size actually does matter.Size actually does matter.
Determine the postion and velocity of a car … no problem
Determine the postion and velocity of a small particle … no problem
Problem!
Heisenberg uncertainty
principle
Cannot have perfect
knowledge of both the position
and velocity
Heisenberg
Dear Steve,
Party
relatively hard!
-Al
The fundamental nature of forces: virtual particlesThe fundamental nature of forces: virtual particles
Et h Heisenberg E = mc2 Einstein
e-
ee++ee--
qqqq
ee++ee--
qqqq
ee++ee--
qqqq
ee++ee--
qqqq ee++ee--
qqqqee++ee--
qqqq
ee++ee--qqqq
ee++ee--
qqqq
ee++ee--
qqqq
ee++ee--
qqqq
ee++ee--
qqqq
ee++ee--
qqqq qqqq
qqqq
ee++ee--
qqqq
ee++ee--
qqqq
qqqq
ee++ee--
Much ado about NOTHING:Much ado about NOTHING:
Nothing is somethingNothing is something
Nothing has energy Nothing has energy
Nothing interacts with somethingNothing interacts with something
-R. Kolb
qqqq
qqqq
qqq
qqq
qqq
qqq
The essence of mass at the quantum levelThe essence of mass at the quantum level(quantum field theory)(quantum field theory)
-MSSL astrophysics group
BANG!
TIME
Very hot, dense primordial soup of fundamental particles
At 0.000001 second after bang, protons and neutrons form
At 3 minutes, light nuclei form
At ~300,000 years, t = 3000 degrees, atoms form and light streams freely
t=~13 billion years, Brittney Spears gets married … again
Modern accelerators study processes at energies that existed VERY early in the universe
Another form of time travel !
What were forces like at those temperatures?
What types of particles existed?
Quantum Chromodynamics - QCD
Similar to QED … But ... Gauge field carries the charge
q q
distance
energy density, temperature
rela
tive
stre
ngth
asymptotic freedom
qq qq
confinement
q qqq
Relativistic heavy ions at Brookhaven National Laboratory
The view from above
STAR
Au-Au collision in the STAR detector
The PHOBOS Detector (2001)
Ring Counters
Time of Flight
Spectrometer
• 4 Multiplicity Array
- Octagon, Vertex & Ring Counters• Mid-rapidity Spectrometer• TOF wall for high-momentum PID• Triggering
- Scintillator Paddles Counters- Zero Degree Calorimeter (ZDC)
Vertex
Octagon
ZDC
z
yx
Paddle Trigger Counter
Cerenkov
1m
137000 silicon pad readout channels
Central Part of the Detector
(not to scale)
0.5m
Au-Au event in the PHOBOS detector
Collision region is football shaped
Elliptic flow12
63
9
12 3 6 9 12
Num
ber
of p
arti
cles
(reaction plane)
Flow quantifiedFlow quantified
dN/d(R ) = N0 (1 + 2V1cos (R) + 2V2cos (2(R) + ... )
b (reaction plane)
Elliptic Flow at 130 GeV
Phys. Rev. Lett. 89 222301 (2002)
(PHOBOS : Normalized Paddle Signal)
Hydrodynamic limit
STAR: PRL86 (2001) 402
PHOBOS preliminary
Hydrodynamic limit
STAR: PRL86 (2001) 402
PHOBOS preliminary
Thanks to M. Kaneta
Flow vs Pt and Hydro describes low pt
vs. particle mass, fails at high pt and high-
T. Hirano
(consider velocity and early, self-quenching asymmetry)
Places to learn more:Particle and nuclear physics links
http://pdg.lbl.gov
http://particleadventure.org
http://www.slac.stanford.edu/gen/edu/aboutslac.html
http://www.bnl.gov/bnlweb/sciindex.html
http://www.bnl.gov/rhic/
http://public.web.cern.ch/public/
http://www.fnal.gov/
http://www.er.doe.gov/production/henp/np/index.html
http://www.science.doe.gov/hep/index.shtm