1. Syllabus and Introduction 2. HEP Infomercialbrandta/teaching/sp2009/docs/phys3313-lec1.pdfPHYS...

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PHYS 3313 Lecture #1Wednesday January 21, 2009

Dr. Andrew Brandt1. Syllabus and Introduction2. HEP Infomercial3. Ch. 1

Please turn off your cell-phones, pagers and laptops in class

http://www-hep.uta.edu/~brandta/teaching/sp2009/teaching.html

Who am I?B.S. Physics and Economics College of William&Mary 1985PH.D. UCLA/CERN (UA8 Experiment-discovered hard diffraction) 1992

1992-1999 Post-doc and Wilson Fellow at Fermilab-Discovered hard color singlet exchange JGJ-1997 PECASE Award for contributions to diffraction-Proposed and built (with collaborators from Brazil) DØ Forward Proton Detector

-QCD and Run I Physics Convenor-Trigger Meister, QCDTrigger Board Rep., Designed Run II Trigger List

1999-2004 present UTA Assistant Prof 2004-present Assoc. Prof-OJI, MRI, ARP awards for DØ FPD-2005 started fast timing work (ARP, DOE ADR)-2008 sabbatical on ATLAS

Logistics• Physics 3313, Spring 2009, Room 105 SH129

MW 1:00-2:20• Instructor: Andrew Brandt 817 272-2706,

brandta@uta.edu• Office Hours: MW 2:30 – 3:30, Tues. 2:00-3:00,

by appointment (344 Physics CPB)• http://www-hep.uta.edu/~brandta/teaching/sp2009/teaching.html

• Textbook: “Concepts of Modern Physics” by Beiser (6th Ed.)

Grading1. Grades will be weighted as follows:

Homework+quizzes 25%2 Midterms (Mar 11, April 22) 50%Final (May 11, 11:00) 25%

2. Drop lowest 2 HW’s and 1 Quiz, final is comprehensive, NO Makeup tests, quizes, late HW

3. Physics Clinic SH 224 is useful free resource for problem sets, but get as far as you can on your own

Attendance and Class Style• Attendance:

– is STRONGLY encouraged, to aid your motivation I give pop quizzes

• Class style:– Lectures will be primarily on electronic media

(I hope)• The lecture notes will be posted AFTER each class

– Will be mixed with traditional methods (blackboard)

– Active participation through questions and discussion are STRONGLY encouraged

Modern Physics Course Material

Survey class:• Special Relativity• Wave-Particle Duality• Bohr Atom• Quantum Mechanics• Statistical Mechanics

Modern Physics deals with the fast and/or small wheredifferent rules apply from classical physicsModern Physics is not current physics!

High Energy Physics at UTA

UTA faculty Andrew Brandt, Kaushik De, Amir Farbin, Andrew White, Jae Yu along with

many post-docs, graduate and undergraduate students investigate the basic forces of nature through particle physics studies at the world’s

highest energy accelerators

In the background is a photo of a sub-detector of the 5000 ton DØ detector. This sub-detector was designed and built at UTA and is currently operating at Fermi National Accelerator Laboratory near Chicago.

Structure of Matter

cm

Matter

10-9m

Molecule

10-10m 10-14m

Atom Nucleus

Atomic Physics

NuclearPhysics

High energy means small distances

Nano-Science/Chemistry10-15m

u

<10-18m

QuarkBaryon

Electron

<10-19mprotons, neutrons,

mesons, etc.π,Ω,Λ...

top, bottom,charm, strange,

up, down

High Energy Physics

(Hadron)

(Lepton)

Periodic Table

All atoms are madeof protons, neutronsand electrons

Helium Neon

ud

u u

d d

Proton NeutronElectron

Gluons hold quarks togetherPhotons hold atoms together

What is High Energy Physics? Matter/Forces at the most fundamental level.

Great progress! The “STANDARD MODEL”

BUT… many mysteries

=> Why so many quarks/leptons??

=> Why four forces?? Unification?

=> Where does mass come from??

=> Are there higher symmetries??

⇒What is the “dark matter”??

⇒Will the LHC create a black hole

that destroys the Earth? NO! See: http://public.web.cern.ch/Public/en/LHC/Safety-en.html

Role 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 a time just after the Big Bang can be made

• Two method of accelerator based experiments:– Collider Experiments: pp, pp, e+e-, ep– Fixed Target Experiments: Particles on a target– Type of accelerator depends on research goals

Fermilab Tevatron and CERN LHC• Currently Highest Energy

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

13M Joules on 10-4m2)⇒Equivalent to the K.E. of a 20

ton truck at a speed 81 mi/hr

Chicago↓

Tevatron p

p CDF

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

• Highest Energy proton-proton collider in fall 2008 – Ecm=14 TeV (=44x10-7J/p

1000M Joules on 10-4m2)⇒Equivalent to the K.E. of a 20

ton truck at a speed 711 mi/hr

1500 physicists130 institutions30 countries

5000 physicists250 institutions60 countries

Particle Identification

InteractionPoint

electronphoton

jet

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

Ä B

Scintillating FiberSilicon Tracking

Charged Particle TracksCalorimeter (dense)

EM hadronic

Energy

Wire Chambers

Magn

et

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

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’

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).

The Standard Model

• Current list of elementary (i.e. indivisible) particles

• Antiparticles have opposite charge, same mass

The strong force is different from E+M and gravity!new property, color chargeconfinement - not usual 1/r2

Standard Model has been very successfulbut has too many parameters, does notexplain origin of mass. Continue to probeand attempt to extend model.

UTA and Particle Physics

Fermilab/Chicago

CERN/Geneva

ILC? U.S.?

Building Detectors at UTA

High Energy Physics Training + Jobs

EXPERIENCE:1) Problem solving 2) Data analysis3) Detector construction4) State-of-the-art high speed electronics 5) Computing (C++, Python, Linux, etc.)6) Presentation 7) Travel

JOBS:1) Post-docs/faculty positions2) High-tech industry3) Computer programming and development4) Financial

My Main Research Interests

• Physics with Forward Proton Detectors• Fast timing detectors• Triggering (selecting the events to write to

tape): at ATLAS 200/40,000,000 events/sec

DØ Forward Proton Detector (FPD)

• Quadrupole Spectrometers• surround the beam: up, down, in, out• use quadrupole magnets (focus beam)

- a series of momentum spectrometers that make use of accelerator magnets in conjunction with position detectors along the beam line

• Dipole Spectrometer• inside the beam ring in the horizontal plane

• use dipole magnet(bends beam)

• also shown here: separators (bring beams together for collisions)

A total of 9 spectrometers comprised of 18 Roman PotsData taking finished, analysis in progress (Mike Strang Ph.D.)

Detector ConstructionAt the University of Texas, Arlington (UTA), scintillating and optical fibers were spliced and inserted into the detector frames.

The cartridge bottom containing the detector is installed in the Roman pot and then the cartridge top with PMT’s is attached.

One of the DØ Forward Proton Detectors builtat UTA and installed in the Tevatron tunnel

Tevatron: World’s Highest Energy ColliderFermilab

High-tech fan

FP420: Particle physics R&D collaboration that proposes to use double proton tagging at 420m

as a means to discover new physics

FP420 Overview

NEW

ATLAS version: AFP Atlas Forward ProtonsSubmitted LOI, Under Review! Feb. 1 at CERN!

Central Exclusive Higgs Productionpp→ p H p : 3-10 fb

beam

p’

p’roman pots roman pots

dipole

dipole

22 )''( ppppM H −−+=

E.g. V. Khoze et alM. Boonekamp et al.B. Cox et al. V. Petrov et al…Levin et al…

∆M = O(1.0 - 2.0) GeV

Idea: Measure the Missing mass from the protons

Hgap gap

b

b -jet

-jet

ηp p

Arnab Pal

n=1 n>>1

Cerenkov Effect

Use this property of prompt radiation to develop a fasttiming counter

particle

Background Rejection

Ex, Two protons from one interaction and two b-jets from another

Fast Timing Detectors for ATLAS

WHO? UTA (Brandt), Alberta, Louvain, FNAL

WHY?

How? Use timing to measure vertex and compare to central tracking vertex

How Fast? 10 picoseconds (light travels 3mm in 10 psec!)

Pedro Duarte (M.S.)Shane Spivey (ex-GRA)Ian Howley (GRA)

proton

Fused Silica Bars• 9 cm bars• Some converted to mini-bars

60 psec

Spread in timing as f(λ)

since n(λ)

Simulation by Joaquin Noyola (UG)other studies by UGChance Harenza+Alek Malcolm

MCP-PMT Operation

FaceplatePhotocathode

Dual MCP

Anode

Gain ~ 106

Photoelectron ∆V ~ 200V

∆V ~ 200V

∆V ~ 2000V

photon

Test Beam• Fermilab Test beam T958 experiment to study fast

timing counters for FP420 (Brandt spokesman)

• Used prototype detector to test concept

• Test beam at Fermilab Sep. 2006, Mar.+Jul. 2007

• CERN October 2007, June 2008

Time resolution for the full detector system:1. Intrinsec detector time resolution2. Jitter in PMT's3. Electronics (AMP/CFD/TDC)4. Reference Time

Latest QUARTIC Prototype

Testing long bars 90 cm, more light than 15 mm mini-bars (due to losses in air light-guide) but more time dispersion due to n(λ)

FP420 Timing Setup

Data Acquisition• Lecroy 8620A

6 GHz 20 Gs• Lecroy 7300A

3 GHz 20/10 Gs• Remotely operated

from control room• Transfer data periodically

with external USB drive

Good Event

5 ns/major division

Online Screen Capture

one histo is 10 psper bin others are 20 ps

delta timebetweenchannels

Dt

QUARTIC Long Bar Resolution

56.6/1.4=40 ps/bar including CFD!

Laser Tests

laser diode lenses filter splitter

mirror PMT

Laser setup operational

Howley, Hall, Lim, McPhail