PHYS 3446 – Lecture #1

Monday, Aug. 28, 2006 PHYS 3446, Fall 2006Jae Yu

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PHYS 3446 – Lecture #1Monday, Aug. 28, 2006

Dr. Jae Yu

1. Who am I?2. Class time and location3. Information and communication sources4. Class specifications and style5. Class plans

• Syllabus• Special semester projects

6. Lab7. Evaluation Policy8. This class…


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Who am I?• Name: Dr. Jaehoon Yu (You can call me Dr. Yu)• Office: Rm 342, Chemistry and Physics Building• Extension: x22814, E-mail: [email protected] • My profession:High Energy Physics (HEP)

– Collide particles (protons on anti-protons or electrons on anti-electrons, positrons) at the energies equivalent to 10,000 Trillion degrees

– To understand• Fundamental constituents of matter• Interactions or forces between the constituents• Origin of Mass• Creation of Universe (Big Bang Theory)

– A pure scientific research activity• Direct use of the fundamental laws we find may take longer than we want but • Indirect product of research contribute to every day lives; eg. WWW

mailto:[email protected]


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High Energy Physics

Structure of Matter

10-10m 10-14m 10-15m

<10-18m

10-9m

Matter Molecule Atom Nucleus

u

Quark

<10-19mprotons, neutrons,

mesons, etc.

top, bottom,charm, strange,

up, down

Condensed matter/Nano-Science/ChemistryAtomic Physics

NuclearPhysics

Baryon(Hadron)

Electron(Lepton)

10-2m


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The Standard Model• Assumes the following fundamental structure:

Directly observed in 2000

Discovered in 1995


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Periodic Table

All atoms are madeof protons, neutronsand electrons

Helium Neon

u

du u

d d

Proton NeutronElectron

Gluons hold quarks togetherPhotons hold atoms together


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Mysteries in High Energy Physics? The “STANDARD MODELSTANDARD MODEL” has been extremely successful

BUT… many mysteries

Why so many quarks/leptons??

Why four forces?? Can they all come from one?

Why is there large particle- antipaticle asymmetry?

Does Higgs particle exist?

Where does mass come from??

Are there other theories??


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What are the roles of particle accelerators?• Smash particles together• Act as microscopes and time machines

– The higher the energy, the smaller object to be seen– Particles that only existed at the time of the creation

of the universe can be made• Two method of accelerator based experiments:

– Collider Experiments: pp, pp, e+e-, ep– Fixed Target Experiments: Particles on a target– Each can look for different things


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Fermilab Tevatron and LHC at CERN• Present world’s Highest Energy

proton-anti-proton collider – Ecm=1.96 TeV (=6.3x10-7J/p

13M Joules on 10-4m2) Equivalent to the kinetic energy of

a 20t truck at a speed 81 mi/hrChicago

Tevatron p

p CDF

DØ

Fermilab: http://www.fnal.gov/ ; DØ: http://www-d0.fnal.gov/ CERN: http://www.cern.ch/ ; ATLAS: http://atlas.web.cern.ch/

• World’s Highest Energy proton-proton collider in summer 2007 – Ecm=14 TeV (=44x10-7J/p

1000M Joules on 10-4m2) Equivalent to the kinetic energy of

a 20t truck at a speed 711 mi/hr

1500 physicists130 institutions30 countries

5000 physicists250 institutions60 countries

http://www.fnal.gov/

http://www-d0.fnal.gov/

http://www.cern.ch/

http://atlas.web.cern.ch/




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The International Linear Collider

33km=

21mi

European Design500 GeV (800 GeV)

47 km

=29 mi

US Design500 GeV (1 TeV)

• Long~ linear electron-position colliders

• 10 – 15 years from now

• Takes 10 years to build an accelerator and the detectors


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How can we tell apart particle?

InteractionPoint

electron

photon

jet

muonneutrino -- or any non-interacting particle missing transverse momentum

Ä B

Scintillating FiberSilicon Tracking

Charged Particle Tracks

Calorimeter (dense)

EM hadronic

Energy

Wire Chambers

Mag

net

Muon Tracks

We know x,y starting momenta is zero, butalong the z axis it is not, so many of our measurements are in the xy plane, or transverse


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DØ Detector

• Weighs 5000 tons• As tall as a 5 story building• Can inspect 3,000,000 collisions/second• Record 100 collisions/second• Records 10 Mega-bytes/second• Recording 0.5x1015 (500,000,000,000,000) bytes

per year (0.5 PetaBytes).

30’

30’

50’

ATLAS Detector

• Weighs 10,000 tons• As tall as a 10 story building• Can inspect 1,000,000,000 collisions/second• Will record 200 collisions/second• Records 300 Mega-bytes/second• Will record 2.0x1015 (2,000,000,000,000,000)

bytes each year (2 PetaByte).


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How are computers used in HEP?

Digital Data

Data Reconstruction

pp


13qT

ime

p p

q g

K

“par

ton

jet”

“par

ticle

jet”

“cal

orim

eter

jet”

hadrons

CH

FH

EM

Highest ET dijet event at DØHighest ET dijet event at DØ

0.69 GeV, 472E

0.69 GeV, 475E21

T

11T

How does an Event Look in a Collider Detector?

http://www-d0online.fnal.gov/www/shift/event_pix.html


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Class Time and Location

• Current: 1:00 – 2:20pm, Mon & Wed, SH 105

• Proposal: 1:00 – 2:20pm, Mon & Wed, CPB303


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Information & Communication Source• My web page: http://www-hep.uta.edu/~yu/

– Contact information & Class Schedule– Syllabus– Homework– Holidays and Exam days– Evaluation Policy– Class Style & Communication– Other information

• Primary communication tool is e-mail: Register for PHYS3446-001-FALL06 e-mail distribution list as soon possible Instruction available in Class style & Communication– 5 points extra credit if done by next Wednesday, Sept. 6– 3 points extra credit if done by next Friday, Sept. 8

• Office Hours: 2:30 – 3:30pm, Mondays and Wednesdays or by appointments

http://www-hep.uta.edu/~yu/


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How to subscribe to the class e-mail list?•Log onto your most favorite e-mail account that you read all the time.•Send e-mail to [email protected] without subject and with the following in the body:

Subscribe phys3446-001-fall06 YourFirstName YourLastName

The e-mail should look as follows (note that there are no spaces in the list name):

mailto:[email protected]


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Class Specification• Text Books

– Das and Ferbel, “Introduction to Nuclear and Particle Physics”– R. Fernow, “Introduction to Experimental Particle Physics”

• Reading Assignments– Not just based on the books– We will use published papers as well– Extra credit on class participations and attendances up to 10%

• Homework Assignments: – There will be homework problems randomly assigned throughout the semester

• Two Written Term Exams (15% each)– Term #1: Wed. Oct. 4– Term #2: Wed. Nov. 15

• UTA Large Perpetual Cloud Chamber Projects and Presentations (20%+10%)


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Syllabus• Nuclear Physics (~1/3 of the semester)

– Nuclear Phenomenology– Nuclear Models– Nuclear Radiation

• High Energy Experimental Techniques– Particle energy deposit in matter– Particle detector techniques and detectors– Accelerators

• HEP Phenomenology– Elementary particle interactions– Symmetries– Discrete Transformations– CP violations– The Standard Model


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Syllabus• Neutrinos

– Neutrinos and proton structure functions– sin2W measurements and its impact to Higgs– Neutrino Oscillation

• Electroweak Symmetry Breaking– Standard Model EWSB formalism & Higgs– Minimal Super-symmetric Extension of Standard Model– Other EWSB Theories (SUSY) & Other Types of Higgs– Strategy for Higgs search

• New Phenomena• Will be mixed with appropriate experimental techniques


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Attendances and Class Style• Attendances:

– Will be taken randomly– Will be used for extra credits

• Class style:– Lectures will be on electronic media

• The lecture notes will be posted on the web AFTER each class– Will be mixed with traditional methods– Active participation through questions and discussions are

STRONGLYSTRONGLY encouraged Extra credit….


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Semester Projects• Completion of the UTA Large Perpetual Cloud Chamber

Design– Must participate in a few workshops– Allowed to use the NP lab for your own experiment after the

regular lab• Final project consists of

– A 5 - 7 page paper each (must become a UTA-HEP note): 20% of the total

– A 10 minute power point presentation each: 10% of the total• Report Due and Presentation Dates

– Presentations: Mon. Dec. 4 and Wed. Dec. 6– Report Due: At the beginning of the class on Wed. Dec. 6


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What is the UTA PLCC?• Cloud chamber is a charged particle detection device

– Uses super-cooled, super-saturated, unstable vapor– Displays charged particle trajectories when particles travel through

the vapor– Normally uses ethanol or isopropyl as the medium

• So the chamber involves techniques in both physics and chemistry perfect opportunity for students from the two departments to work together

• New CPB contains a large planetarium with a spacious foyer to display things that stimulate scientific minds– Shows that there are cosmic particles coming from the universe

• They see particle trajectories before and after the planetarium lectures

• This detector can be used for class demonstrations and lab measurements


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Basic Idea of the Cloud Chamber

T=~100oCVisible Track

• Use super-cooled, super-saturated, unstable vapor as the medium• When a charged particle passes through the super-saturated vapor, the

vapor forms droplets along the trajectory of the particle• A strong light beam makes the track appear on the background• The track then falls onto the bottom of the chamber due to gravity


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The Scope of the Project• Dimensions of the proposed chamber:

– The largest such chamber available is 1mx50cm horizontal w/ about 10 cm thick cloud.

– None I have seen had a display that shows an extended trajectory through an entire height.

– All need to be looked at from an angle with respect to horizontal line

• This UTA chamber will therefore be the largest physical dimension in the world

• It will also occasionally show a spectacular breakage of atoms through collisions of heavy particles, such as particles.

1 (H)m 2 (L)m 30 (D) cm


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A Schematic Chamber Diagram

1m

30cm

2mref


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Concerns in the Chamber • Requirements

– The chamber must be very safe!!!– The chamber must look very nice and impressive!!– The chamber must function at all times, continuously!!– The chamber should be require minimal maintenance!!– The chamber should be as compact as possible!!– The chamber shouldn’t be an untouchable!!

• The super-cooled vapor is heavy and settles low on the bottom of the chamber

• Cooling of the vapor should be done evenly and effectively– Cooling coils will be placed at the bottom of the chambers– How do we regulate the temperature?


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Concerns in the Chamber • How do we keep vapor supply continuously without

having to add the medium too frequently?– What medium would be better? – Is there a medium that does not require significant cooling

to be in a super-cooled state?• On what angle with which color light is good for

display– Can people see from the front?– What color trajectories is more visible?

• Which way should be magnetic field be?– How strong a magnetic field?– Which direction should be field be?


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Semester Projects• Four topics

– Chamber structural design• Including the alcohol warmer and support

– Refrigeration • Thermo-electric Module (TEM) design and operation

– Liquid supply and recirculation system– Light and display

• How do we design to show the best


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Laboratory• Location: Room 008 in basement• Time: 1:00 – 3:50pm, Fridays• Requirements: Must be trained for radiation safety• A few measurements throughout the semester

– Lab can be accessed in times other than regular lab• Lab reports are due one week after each measurement

– The report will be peer reviewed by someone out of your team– Review comments are due the week after Will be reflected into

the lab grade• Lab score will be 15% of the total


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Evaluation Policy• Two Term Exams: 15 % each 30% • Lab Score: 15%• Final Semester project paper: 20% • 10 minute Project oral presentation: 10% • Homework: 15%• Quizzes: 10%• Extra Credit: 10%

– Consists of random attendances, colloquium participation, workshop participation and other opportunities


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In This Class• You will learn

– Frontier physics and its history– Building blocks of matters are– How matters interact– The current theories that predict the nature– The experimental techniques to verify and test these theories– How we can make our lives better by establishing good theories

• You are strongly encouraged to work together– One learns enormously talking to others

• This is not going to be a stroll in the park…. • You will earn your mark and feel total fulfillment!!• But most importantly…

We will have a lot of FUN!!!!

PHYS 3446 – Lecture #1

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