Transcript Document 7308016

Notre Dame
High Energy Physics
Theory Group
• The Group:
– 5 graduate students (details later)
– 1 postdoc
• David Diego
– 3 teaching and research faculty
• Ikaros Bigi, Antonio Delgado, Chris Kolda
• Kolya Uraltsev (visitor)
• Student Openings: Delgado “yes”, Kolda “possibly”
Current Students
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Brian Dudley
Joel Griffith
Pokie Olson
Ayan Paul
Dipajan Ray
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U.S.
U.S.
U.S.
India
U.S.
Notre Dame
High Energy Physics
Experimental Group
• The Group:
– 7 graduate students (details later)
– 7 research faculty/postdocs
• Leo Chan, Dan Karmgard, Jeff Kolb, Nancy Maranelli, Dmitri
Smirnov, Wenfang Wang, Jadzia Warchol, + new hire
– 3 technicians plus 1 engineer
• Jeff Marchant, Mike McKenna, Mark Vigneault, Barry Baumbaugh
– 6 teaching and research faculty
• Mike Hildreth, Colin Jessop, Kevin Lannon, John LoSecco
Randy Ruchti, Mitch Wayne
Current Students
BaBar:
DØ:
CMS:
 Kyle Knoepfel
- U.S.
 Jyotsna Osta
- India
• Ted Kolberg
• Jamie Antonelli
- U.S.
- U.S.
• Sean Lynch
• Doug Berry
• David Morse
- U.S.
- U.S.
- U.S.
Now (15 billion years)
Stars form (1 billion years)
Atoms form (300,000 years)
Nuclei form (180 seconds)
Protons and neutrons form (10-10
seconds)
we work here
Quarks differentiate (10-34 seconds?)
??? (Before that)
Anna Goussiou
What is the Universe Made of?
• A very old question, answered many ways during the eons
• The only way to answer this question is by directly confronting
Nature by experiments that can lead to definite conclusions
• Experiments have told us:
– complexity often arises from simple building blocks
• Periodic Table of the Elements, Nuclear Structure
• fundamental constituents are small particles
– diverse phenomena can be manifestations of the same
underlying physics
• the moon’s orbit, a falling apple
– intuition may not necessarily be trustworthy
• our world is really Quantum Mechanical, even though we
don’t see this in everyday life
Fundamental Forces of Nature
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Gravity
Electromagnetism
Weak Nuclear Force
Strong Nuclear Force
}
Relative Strengths
10-40
10-2
ElectroWeak
Force
-6
10
1
The ElectroWeak and Strong forces combine to
form the Standard Model of Particle Physics
On to “Big Questions”
• Particle Physics experiments may be able to answer
– What IS mass?
– Why is there matter at all?
– What is Dark Matter?
– What is the space-time structure of the
Universe?
 Growing synergy between particle and astrophysics
– both fields working together on these questions
• To answer these, we use the language of
Quantum Field Theory, the theory that results
when Quantum Mechanics and Special Relativity
are merged:
• Although very successful from the experimental point of
view and some predictions have been tested to great
accuracy, it is far from being a complete theory:
– the higgs is still to be discovered
– the rôle of the higgs itself introduces certain problems
into the theory
• Therefore theorists go beyond the SM in order to address
questions of physics at TeV scales
• Let me summarize the research interests of the other two
senior members of the group:
– Professor Bigi is interested in flavour physics, i.e., the
physics that deals with the interaction between the
different families of quarks and leptons. These
processes are rare in the SM and evidence for new
physics can come in an excess of some of this effects.
He is also a susy fan.
– Professor Kolda is interested in supersymmetry as a
direction for physics BSM. Supersymmetry predicts the
existence of new particles to be discovered at the LHC
and provides us with a nice explanation for the EW
scale.
• In my case I am interested in the EW sector and
studying models that may provide us with an
explanation of what the higgs is and why it is much
lighter than the Planck mass
– There are models where the higgs is a fundamental
particle and the scale is protected by a symmetry:
susy, little higgs
– There are even models without a higgs
• My work is on the study of different models, their
viability both on the theoretical side, i.e. no
inconsistencies, and on the experimental side, i.e. they
do not contradict any measurement we have already
done.
• It is a great opportunity that LHC will start to collect data
next years and to probe the TeV scale so it will be a
challenging time for particle physics .
• Because of that we have to take advantage of our
experimental colleagues that have a major rôle in CMS
• As a last word I should say that the group is also
interested on any interplay of particle physics and
cosmology taking into account that there is a very good
astro group here in ND.
Experimental Projects
• DØ/CDF at the Fermilab Tevatron
– proton-antiproton collisions at 2.0 TeV
– widespread current effort in Run II (soft/hardware, physics)
• BaBar at Stanford Linear Accelerator Center
– e+e- collisions at ~10 GeV
– Studies of CP Violation, potential effects of new physics
• CMS at the CERN LHC
– proton-proton collisions at 14.0 TeV
– detector development, construction, testing, commissioning
– Quarknet program for H.S. students, teachers
• International Linear Collider
– R&D on Muon System, Beam Instrumentation
Chicago
FERMILAB Accelerator Complex
Booster
p
Tevatron
p
p source
Main Injector
CDF & DØ Experiments:
& Recycler
• World’s highest energy
particle collisions
• Search for mechanism of mass generation (Higgs boson)
• Direct searches for other New Physics
• Precision measurements of fundamental particles
Hildreth, Lannon, Ruchti, Wayne
SLAC ACCELERATOR FACILITIES
International Linear Collider R&D:
• ILC: explore New Physics at the TeV Scale with
BaBar Experiment:
• Understanding the precision
origins of measurements
matter in the Universe
R&D:
Detector Development
at ND, FNAL,
(CP Violation and• the
matter-anti-matter
asymmetry)
Instrumentation
SLAC, KEK
• Searching for new Accelerator
physics at high
mass scales at
with
precision measurements of rare processes
Hildreth, Wayne
Jessop, LoSecco
World
CERN: The
LargeTravel
Hadron Collider
The CMS Experiment at the LHC:
• World’s highest energy collisions (7x Tevatron) starting late 2008
• Focus of High Energy Physics for the next decade
• Search for breakdown of the Standard Model, New Physics at the
TeV scale. We have no idea what will be found
Hildreth, Lannon, Jessop, Ruchti, Wayne
Chooz, France
Chooz-far
Double Chooz Experiment:
• reactor-produced neutrinos
• Attempt to measure a
Chooz-near
fundamental
parameter of the
neutrino mass matrix (ne - nt
mixing)
• understand origin of neutrino
masses
LoSecco
LHC Physics Center at Fermilab
• Center for US involvement in CMS
– “local” center of software/analysis
expertise
– preparing to be very active in
commissioning CMS
• Close!
• Easy way to get involved “part time”
– developing tutorials, example analysis
packages, etc.
– nucleus of consultants for newcomers
• “Senior” ND personnel involved
Conclusions
• Not an easy game, but the payoff could be HUGE
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Origin of mass?
Understanding Energy Scales for the Fundamental Forces?
New forms of matter (Supersymmetry)?
Structure of Spacetime
• Tevatron will be collecting up to 2x the current dataset
over the next 2 years or so, CMS coming very fast
– lots of scope for new phenomena to appear
• Double Chooz starting very soon
• Fascinating time to be a particle physicist:
– If we don’t find new things at the Tevatron, the LHC will
• huge jump in energy and data quantity
– Within the coming years, we will have answers!
• (and more questions, of course)