Raymond E. Frey
Research in "Fundamental Physics" of Elementary Particles and
Gravitational Waves
[
Overview of UO HEP experimental
research
(for prospective graduate students).]
Search for Gravitational Waves and GW Astronomy: LIGO
The possibility of opening a new window on the universe with
gravitational waves has led to the LIGO project. Gravitational
waves were predicted by Einstein's General Theory of Relativity and
have not yet been directly observed. Such an observation is the first
goal of LIGO. LIGO consists of two observatories, one in Washington
state and one in Louisiana. The UO LIGO group mostly works at the
Hanford observatory and
on data analysis on campus. Starting 11/2005, LIGO began a
long
Science Run (S5) with the detectors at their design sensitivities. This
run will continue until about the end of 2007.
Some introductory papers/documents about LIGO:
The UO-LIGO group consists of (2006):
- Faculty: Brau, Frey, Strom
- Research scientists: Isabel Leonor, Robert Schofield
- Graduate students: Emelie Harstad, Masahiro Ito (PhD 2006), Rauha
Rahkola (PhD 2006)
Probing Electroweak Physics of the Sandard Model at SLAC:
SLD/SLC and BaBar
Incisive and precise tests of (aka high-energy physics) have
shown that (1) the Standard Model
of elementary particle physics is correct at low energy (< 100 GeV
or so), and (2) the SM is incomplete and breaks down at a higher
energy.
The BaBar
experiment
at SLAC is exploring the physics of the b-quark in great detail. This
has allowed BaBar to discover CP violation in the B system and to
search for new physics in rare decay processes. CP violation represents
an asymmetry between matter and anti-matter. A similar tiny asymmetry
was also necessary in the early universe in order to give rise to the
observed preponderence of matter over anti-matter in today's universe.
BaBar is also exploring rare decay modes which can provide indirect
evidence for new physics.
The SLD
experiment at the Stanford Linear Accelerator Lab (SLAC) produced polarized
electron beams which collided with positrons at a center of mass energy
of 91 GeV to produce the Z0 particle (mass is about 91 GeV/c2
). This provided the opportunity to make precision tests of the
electroweak theory of the Standard Model by studying the Z0 production
rate and its decay products in the SLD detector. One key result is a
world best measurement of the weak mixing angle, also known as the
Weinberg angle, which determines the ratio of the strength of the
electromagnetic and weak force couplings in the electroweak theory. Its
value was determined
by SLD to be 0.23098 +/- 0.00026. Taken together with electroweak
measurements from LEP at
CERN, this predicts that the postulated Higgs particle can not be
very massive, with rest energy less than about 200 GeV. This implies
that the Higgs and/or the energy scale of electroweak symmetry breaking
is just around the corner, and would be accessible at a future linear collider (see
below). The SLC and LEP results at the Z0 are summarized in the
following review article: Physics Reports 446 (2006) [hep-ex/0509008].
Future
electron-positron Linear Collider (the ILC)
New Linear e+e- colliders ( ILC
) may be in the future of particle physics.
The HEP Advisory Panel report
has (Jan 2002) given this its top priority.
Some LC studies which Ray has
worked on:
Ray was previously a co-leader of the Calorimeter
Working Group of American LC Physics Group
and is currently
a co-leader for the SiD
detector
concept.. Here are some
recent
calorimeter-related talks and papers:
- Plenary introduction (pdf)
and calorimeter talk (pdf)
at the Paris LCWS, 2004.
- Calorimeter Considerations for a Linear Collider Detector, Calor
2002:
| Talk
(pdf) | Proceedings
(pdf) |
- Design Considerations for a Silicon/Tungsten Electromagnetic
Calorimeter
for a LC Detector, Calor 2002: | Talk
(pdf) | Proc
(pdf) |
- A Silicon/Tungsten ECal for the SD Detector, LCWS 2002, Korea: Talk
(pdf)
- Calorimeter Summary, LCWS 2002, Korea: Talk
(pdf)
The Snowmass 1996 Top report is here
(ps format) and the source tex and figures (gzipped tar) are here.
A General talks on LC Physics and Experimentation:
LC
Experiments and Detectors, APS Denver 2004.
Neutrino Physics at Fermilab
The
electroweak force, as well as the force which binds the quarks (QCD),
is being tested at low Q2 with high precision using a
high-energy beam of neutrinos at the Fermi National Accelereator
Laboratory
(Fermilab) near Chicago. Ray, along with
other UO physicists, is a member of the relatively small experimental
group,
known as NuTeV. Data
taking ended Summer 1997.
Teaching:
- 2004-5, 2005-6, 2006-7: Physics 251, 252, 253
- 2003-4: Physics 251, 252, 253; Astronomy 321,
Winter
- 2002-3: Physics 251-2,
Foundations of Physics (F,W);.
- 2001-2: Physics 251-2 (F,W); Physics
410 (W) (see below).
- Ray developed a new course on mathematical methods for physics in
WInter
2001, which is listed as Phys 410 for now.
- 1998-2000: Electronics sequence 431,432,433 (and 531,532,533).
See the
web pages for 431,
432,
or 433
for more information.
- Ray's notes for Phys 431, Analog Electronics: pdf
format - can be used with permission
- Notes for Phys 432, Digital Electronics: pdf
format - can be used with permission
Electricity is also fun for elementary school. Here are some notes
(ps) for presentations to 3rd grade kids who are doing the state
science kits
on electricity.
Some publications:
``Experimental Observation of Isolated Large Transverse Energy
Electrons
with Associated Missing Energy at sqrt{s} = 540 GeV'', Phys. Lett. 122B
(1983) 103. (Discovery of the W particle.)
``Experimental Observation of Lepton Pairs of Invariant Mass Around
95 GeV/c^2 at the CERN SPS Collider'', Phys. Lett. 126B (1983) 398.
(Discovery
of the Z particle.)
``Measurements of Z Boson Resonance Parameters in e+e-
Annihilation'',
Phys. Rev. Lett. 63 (1989) 2173. (Discovery of number of neutrino
species
< 4.)
``Radiative Corrections to the Z0 Resonance'', Phys. Rev. D37 (1988)
56. (Some theory underlying the previous measurement.)
``First Observation of Beamstrahlung'', Phys. Rev. Lett. 62 (1989)
2381.
(A new phenomena at e+e- linear colliders.)
``Measurement of Electron Beam Polarization from the Energy Asymmetry
of Compton Scattered Photons'', R. Field, R. Frey, M. Woods, A.
Arodzero, and J. Zhou, IEEE Trans. Nucl. Sci. 45 (1998) 670. (Technique
for measurement of beam polarization at SLC.)
``Top Quark Physics: Future Measurements", Summary Report for
Snowmass
1996: New Directions for High Energy Physics, eds. D.G. Cassel, L.T.
Gennari,
and R.H. Siemann; hep-ph/9704243, March 1997. (Some of the exciting
physics
for the next accelerator at the high-energy frontier.)
``A High-Precision Measurement of the Left-Right Z0
Cross-Section Asymmetry'', Phys. Rev. Lett. 84 (2000) 5945. (The final
SLD ALR measurement and world best measurement of the
electroweak mixing angle.)
``Observation of CP Violation in the B0 Meson System'', Phys. Rev.
Lett. 87 (2001) 091801. (Matter-antimatter asymmetry in the 3rd
quark generation from BaBar.)
``Design Considerations for a Silicon-Tungsten Electromagnetic
Calorimeter for a Linear Collider Detector,'' Proc. 10th International
Conference on Calorimetry in High Energy Physics, World Scientific,
2002, R.-Y. Zhu ed., pg. 304. (A new way to do calorimetry for the LC.)
``Analysis of LIGO data for gravitational waves from binary
neutron stars,'' Phys. Rev. D 69, 122001 (2004). (One of
the first LIGO observational results.)
rayfrey@uoregon.edu
Professor of Physics
