Embed Size (px)
Citation preview
Elementary Particle Physics in a Nutshell
Elementary Particle Physics in a Nutshell
● Elementary particle physics explores the nature of the very large and the very small
Elementary Particle Physics in a Nutshell
● Elementary particle physics explores the nature of the very large and the very small
● ... forces within the nucleus
Elementary Particle Physics in a Nutshell
● Elementary particle physics explores the nature of the very large and the very small
● ... forces within the nucleus
● ... the stuff of the universe
Elementary Particle Physics in a Nutshell
● Elementary particle physics explores the nature of the very large and the very small
● ... forces within the nucleus
● ... the stuff of the universe
● ... the unity of forces
● ...searches for new elementary (not just elemental) forms of matter
● Explores the dominance of matter over anti-matter
● ... the unification of physical symmetries in a hot universe
● ... origins of mass
● ...searches for new elementary (not just elemental) forms of matter
● Explores the dominance of matter over anti-matter
● ... the unification of physical symmetries in a hot universe
● ... origins of mass
● ... the fundamental theories of “life, the universe and everything “
Study basic constituents of matter and the forces that
govern their actions
May 4, 2005 Drew Baden 10
The Labs
Fermilab (Near Chicago)The Tevatron
proton-antiproton colliderat c.o.m. Energy = 2TeV
6.3 km circumference
CERN (Geneva, Switzerland)Tdhe LHC
proton-proton colliderat c.o.m. Energy = 14TeV
27 km circumference
Tevatron
not to scale
May 4, 2005 Drew Baden 13
The Experiments
DØ - FermilabWeighs 5000 tons~106 channels of informationInspects ~3-30 x106
collisions/sec.Running now, mature experiment,
high quality data
CMS - CERNWeighs 12,500 tons~107 channels of informationInspects ~40-1000 x106
collisions/sec.First physics data: end of 2009
D-Zero
May 4, 2005 Drew Baden 15
Slice of CMS7m
Are there undiscovered principles of nature: new symmetries, new physical laws?
The kinds of questions we ask
What is dark matter? How can we make it in the laboratory?
Are there extra dimensions of space?
The kinds of questions we ask
Cosmic tug of war How can we solve the mystery of dark
energy?
Composition of the universe
Do all the forces become one?
The kinds of questions we ask
Standard Model particles, many more may exist
Why are there so many kinds of particles?
What is mass?
>12 orders of magnitude in mass!
W photonmass = 0
mass = 80.4 GeV
What is the origin of electroweak symmetry breaking?
The kinds of questions we ask
What happened to the antimatter?
Now
Matter Antimatter
Then
How did the universe come to be?
E=mc2
xkcd.com
Cold
Hot
Electroweak Unification
EM-like
Weak-like
EM/Weak interactionsunified at large Energy/ momentum transfer
EM/Weak interactionsunified at large energy/momentum transfer
Gauge theory (like electromagnetism) describes fermions (quarks) which carry an SU(3) charge (color) and interact through the exchange of vector bosons (gluons)
Quantum Chromodynamics
In a more general theory (GUT), expect unification w/ electroweak force
● Interesting features:
- gluons themselves have color- interactions are strong- coupling constant runs rapidly
becomes weak at momentum transfers above a few GeV
Accumulate world's largest data sets at highest energies before LHC era
physics menu includes:
Precision top physics (first ever) Precision EW physics (new
observations of di-boson states) Searches: Higgs* and new physics
(explore much of SUSY phase space, extra-dimensions, exotic matter states)
QCD and proton hadronic structure (new levels of precision, smallest distance scales yet)*
Discover new states predicted by QPM Heavy flavor physics* (Precision
measurements in heavy quark sector, relationship between generations, matter antimatter asymmetry,...
Mature experiment, high quality data
LHC: The New Frontier
physics menu includes:
Copious top production Test of EW physics to “unitarity limit” Copious Higgs production*, test SM
vs. SUSY Higgs Direct observations of SUSY states*
or elimination of the lifetime work of many theorists :)
Order of magnitude gain in physics reach at smallest distance scales*
Open door to weirdness: black hole production, extremely massive exotic
states, new types of strong interactions, extra-dimensions*....
A new era of HEP research starts this Fall!
* general group interests at present
Various Technical Projects
At the CMS test beam
Constantly pushing technological envelopes:
● High speed electronics● Computing● Precision detector readout● Radiation and high magnetic field tolerant devices● Fast, exceptionally sensitive detector technologies● State of the art data analysis techniques● ...
1990
World's 1st web site and a the WWW, a gift to the world from HEP
Workshops and Physics Schools
Around Fermilab
Around CERN
CERN Surroundings
Where do HEP students go?
HEP students and postdocs go many places after completing their research, some (very few really) examples: Industry
Industrial research and instrumentation design Wireless technology and network infrastructure IT Consulting Financial analysis, modeling Design of medical treatment devices
Non-Industry Private and public “think tanks” National research laboratories (not only HEP) Law, Media
Academia 4-year undergraduate colleges Tier-1 research universities
But, you should only choose this or any other research area because you are interested in the physics!
no passion, no progress!
What can you learn along w/ physics?Lots: detector technologies, typical HEP experiments can easily employ
many varieties of particle detection – enormous amount of practical physics in development of detector systems high performance data readout systems, electronics (HEP detectors
must typically process 10's of TB of data each second) high performance computing:
need to cull above data rate to manageable levels in real time handle data sets at many PetaByte level
sophisticated data analysis techniques, statistical reasoning, multivariate approaches for problems -> extracting maximal information from data working with engineers and detector/accelerator physics experts to
bring experiments on-line experience w/ detailed simulations of detector systems and physics
processes join in a large talented physics community, amazing access to
expertise in world wide community + many opportunities to contribute to high-profile efforts
Interested in Experimental HEP?
Great opportunities for graduate students this year
Some resources:- seminars, colloquia, ...- Symmetry Magazine: http://www.symmetrymagazine.org- CERN Courier: http://cerncourier.com- Femilab Today: http://www.fnal.gov/pub/today/
A fantastic time to get involved!
Want to try learn more? I'll be happy to meet with interested students.● Lab Tours● Project Details● Opportunities to get involved at UVa, CERN, Fermilab
