Particle Physics at UW The EPE Group

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Particle Physics at UWThe EPE Group

• Gordon Watts

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Introduction To
High Energy Physics
(bubble chamber picture from my Fathers era)
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Fundamental Nature of Matter The Universe
Fortson
Picture of Galaxy NGC 6070 and a CDF Top Event
Overlaid Found by googling Universe
WMAP
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???
What is Dark Matter/Dark Energy?
Electro-Weak Symmetry Breaking?
How Does Gravity Fit!?
How Does HEP Tackle These Problems?
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The Domain of High Energy Physics
Matter
Molecule
Atom
Nucleus
Quark
Baryon
(Hadron)
u
10-14m
cm
10-10m
10-15m
10-9m
lt10-19m
protons, neutrons, mesons, etc. p,W,L...
top, bottom, charm, strange, up, down
Chemistry
Atomic Physics
Nuclear Physics
Electron
Mass
(Lepton)
proton 1 GeV/c2
lt10-18m
High Energy Physics
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• Fundamental particles
• 3 families of fundamental fermions

u
u
Electric Charge
d
ne e
nm m
nt t
proton
q 0
leptons
q -1
everyday matter
u d
c s
t b
q 2/3
quarks
q -1/3
Color Charge (3)
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How is the SM Doing?
Summer 05
Measurements from Colliders, Table Top
Experiments, Nuclear Labs, 1000s of people and
1000s of papers.
Now Over Constrained
Good Worst Discrepancy is about 2.7 s
Weve not found a break over many years of
precision measurements!
So, whats the problem?
Pull (fitted - measured)/error
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Not the End of the Story
We have known for a long time
Recently
SM is internally inconstant (hierarchy, Higgs
Self couplings, etc.) Gravity Aesthetics Too
many free parameters!

• Dark Energy Dark Matter
• Neutrino Masses

Slew of theories
But Experiment currently provides us with no
direction
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Interconnections
Consistentunderstanding?
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Further Investigation
Astrophysics
satellites, telescopes, underground DM searches
n
factories, mass determination, CP violation
Accelerator
Accelerator DM search, SM breakdown
Controlled Experiment Measure Most Aspects
Energy Never High Enough Nor Luminosity
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The faculty
Lubatti
Mockett
Burnett
Zhou
Rothberg
Watts
And hopefully someone else
Supported by...
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Post-docs

• Aran Garcia-Bellido
• At Fermilab Fulltime
• Co-Leading the SingleTop Analysis Group, Level 3
  DAQ, etc.
• About to advertise for another

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The Graduate Students

• Thomas Gadfort
• 4rd year. Working on Search (Discovery?) of
  Single Top Quark Production using a Matrix
  Element technique.
• Matt Tilley
• Finishing up a masters (graduate this summer).
• Topic is b-tagging at DZERO.
• Dan Ventura Reading Course.
• We have an open slot for a new graduate student.

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The Undergraduates

• Laura Bodine Imai Jen-La Plante Graduated
• U of Wisconson and U Chicago doing HEP.
• Amanda Grey
• Did W charge asymmetry MC analysis last year
  (presented poster).
• Working with Pheno group and our group doing LCH
  Olympics

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The experiments
DZERO will collect data until LHC turns
on ATLAS First collisions in 2007, first
physics 2008-9.
Burnett Lubatti Watts Zhou
Lubatti Mockett Rothberg Watts Zhou
Lubatti Zhou
(Geneva, Switzerland)
2007
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In HEP?
The Missing Ingredients
The Higgs
How do we fix the Standard Model?
Or what is that DE/DM?
Precision Measurements
Signs of physics at a higher scale
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Precision Measurements
Measurements made by the experiments
Constrain theory parameters
Enough Measurements and
SM is over constrained!
Nothing Over 3s!
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Single Top Analysis
What is Involved?
Thanks Thomas
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What you look for
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Understand Your Backgrounds
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Find Ways To Separate
In A Nut Shell
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Whats it like?
Physics
Computers
Measurements
Hardware
(oh, lots of work)
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Chicago
DØ
DØ
DØ
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Life at Fermilab
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Fermilab
(besides the bison)
This is big science
There are 500 people on the DZERO author list
There are 200 people working full time at DZERO
Another 100 people working full time around the
world
This is not a lonely endeavor!
We do video meetings every now and then
Community of 100-200 graduate students at
Fermilab continuously.
Learn Fast!
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But
We work in small groups
Thomas works with one other graduate student,
myself, and the other students advisor.
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Data March 1!
2001
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Mt event pictures
m
Top Discovery In Run 1 D0 CDF Mt 175.5 pm
Best Measured Quark
e
Missing ET
jet
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Whats UW Up To?
What might you expect in our group?
Building The Experiment
Silicon Detector Upgrade
Level 3 Trigger/DAQ System
Event Display
Particle Theory/EPE Joint Group
Doing the Physics
Working on single-top SM Backgrounds
Single Top Search ATLAS b-tagging, Muons as a
search for new physics
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Level 3 Trigger/DAQ
Level 1 2 Triggers
UW Is Responsible for this
1 of 250 Trigger Nodes (Level 3)
1kHz 250kb/Event
80 Sources (Front End Readout Crates)
There are 1 million readout channels
50 Hz
Most are zero suppressed
Tape
250 Kb per ppbar crossing Crossings happen at 2.5
MHz
Most are junk!
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Event Display
Wire-frame display
Written by Toby Burnett
http//www.fnal.gov/pub/now/live_events/dzero_live
.html
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Layer 0 Silicon

• To find the Higgs, we will need excellent track
  resolution.
• Best achieved with accurate tracking detectors
  close to the beam
• Silicon are the best
• D0 currently has just such a detector
• But is dying due to radiation damage (2-5 fb-1).
• Detector will be installed in March for remainder
  of Run 2.

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ATLAS
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ATLAS and DZERO

• DZERO is drowning in data
• 2 TeV Center of Mass
• Physics is pouring out of the Tevatron
• Most productive years are the next two
• Chance at the Higgs (if LEP was right)
• Many Beyond the SM Searches
• ATLAS
• First beam in 2007
• Non discovery will have serious implications
  (kill SUSY for EWSB)
• 14 TeV Center of Mass
• SM Cross sections up by factors of 2-10.

Help!
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ATLAS
UW Built 1/3 of these
A Huge Construction Project
Physics Reach Will Be Stunning!
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A Muon Drift Tube
HV
-
-
-
-
-
-
-
-
When it happened, how much charge, etc.
Ionizes Gas
Charge Accumulates
Muon
Physics Effort is just starting - Btagging and
Simple SUSY
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Hardware

• Work with our group at CERN this summer to help
  commission the US ATLAS Muon Chamber (see Henry
  Lubatti).
• Work with us at Fermilab to commission the new
  Si-tracker inner layer of the D0 detector (see
  Henry Lubatti)
• ILC - There are two efforts at UW 1) New
  approaches to calorimeter design (see Tianchi
  Zhao) and 2) Design of Silicon inner tracker for
  the ILC detector (see Henry Lubatti).

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Analysis

• ATLAS
• BTagging Studies
• Muon Commisioning and Physics
• DZERO
• Single Top Search
• Light Higgs Studies
• BTagging

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Group Meetings
We Have Two
Joint Theory Meeting
No deep details on either Theory or Experiment
Fast paced, lots of talking over each other
EPE Only Group Meetings
Sometimes a bit more technical
Reading Course
Participate in the Joint Meeting Start with some
simple studies