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Congratulations are due to Professors Nikolai Tolich and Paula Heron.

Professor Tolich has been awarded the 2008 American Physical Society Dissertation Award in Nuclear Physics for his thesis prepared under the supervision of Professor Giorgio Gratta at Stanford.  He shares the award with Dr. Deepshikha Choudhury of Ohio University.   Dr. Tolich is cited “For his dissertation presenting an experimental investigation of terrestrial electron antineutrinos with KamLAND.”

Professor Heron has been elected to the APS Fellowship.   Paula was cited “for her leadership in the physics education research community and development of research-based curricula that significantly impact physics instruction throughout the world."

Our Physics Education Group is Recognized by the APS

The Physics Education Group at the University of Washington recently received the APS Award in Physics Education. This award honors the Group for their sustained commitment to excellence in Physics Education. The group, which includes faculty Lillian McDermott, Paula Heron and Peter Shaffer, focuses their research on teaching and learning of physics, developing curricula, and helping teachers improve their effectiveness. Their early groundbreaking research established the methodology for understanding how students learn physical concepts. This group established an important new role for physics education research within physics departments.

Their citation reads,

“For leadership in advancing research methods in physics education, promoting the importance of physics education research as a subdiscipline of physics, and developing research-based curricula that have improved students’ learning of physics from kindergarten to graduate school.”

We congratulate the Group for their success and we are proud to have them in our Department.

Research overturns accepted notion of neutron's electrical properties

For two generations of physicists, it has been a standard belief that the neutron, an electrically neutral elementary particle and a primary component of an atom, actually carries a positive charge at its center and an offsetting negative charge at its outer edge. The notion was first put forth in 1947 by Enrico Fermi, a Nobel laureate noted for his role in developing the first nuclear reactor. But new research by a University of Washington physicist shows the neutron's charge is not quite as simple as Fermi believed.

Using precise data recently gathered at three different laboratories and some new theoretical tools, Gerald A. Miller, a UW physics professor, has found that the neutron has a negative charge both in its inner core and its outer edge, with a positive charge sandwiched in between to make the particle electrically neutral.  "Nobody realized this was the case," Miller said. "It is significant because it is a clear fact of nature that we didn't know before. Now we know it." This discovery has implications for understanding the strong force, one of the four fundamental forces of nature (the others are the weak force, electromagnetism and gravity).  The strong force binds atomic nuclei together, which makes it possible for nuclei and therefore atoms, the building blocks of all matter to exist.
His analysis was published on line Sept. 13 in Physical Review Letters. The work was funded in part by the U.S. Department of Energy. 

NEWTON'S SECOND LAW OF MOTION, that pillar of classical physics, the formula that says the force on an object is proportional to acceleration, has now been tested, and found to be valid, at the level of 5 x 10^-14 m/s². This is a thousandfold improvement in precision over the best previous test, one carried out 21 years ago (Physical Review D, vol 34, p 3240, 1986). The new test was performed by physicists at the University of Washington using a swiveling torsion pendulum, a special kind of pendulum in which the restoring force is not gravity (as you would have in a hanging pendulum) but is provided by a very thin torsion fiber. One implication of Newton's law is that the pendulum's frequency (its tick-tock rate) should be independent of the amplitude of its swiveling (as long as the oscillation is small). Looking for a slight departure from this expected independence the Washington researchers watched the pendulum at very small amplitudes; in fact the observed swivel was kept so small that the Brownian excitation of the pendulum was a considerable factor in interpreting the results. Newton's second law is expected to break down for subatomic size scales, where quantum uncertainty frustrates any precise definition of velocity. But for this experiment, where the pendulum has a mass of 70 g and consists of 10²⁴ atoms, quantum considerations were not important.

According to one of the scientists involved, Jens Gundlach (206-616-3012, jens@phys.washington.edu), this new affirmation that force is proportional to acceleration (at least for non-relativistic speeds), might influence further discussion of two anomalies: (1) oddities in the rotation curves for galaxies---characterizing the velocity of stars as a function of their radii from the galactic center---suggest either that extra gravitational pull in the form of the presence of as-yet-undetected dark matter is at work or that some new form of Newton's Second Law could be operating (referred to as Modified Newtonian Dynamics, or MOND); and (2) the ongoing mystery surrounding the unaccounted-for accelerations apparently characterizing the trajectory of the Pioneer spacecraft. (Gundlach et al., Physical Review Letters, upcoming article).

Source: The Johns Hopkins University
Content: Press Release
Date Issued: 9 April 2007 *********************************************************************** FELLOWSHIPS AIM TO STIMULATE YOUNG THEORETICAL PHYSICISTS LHC Theory Initiative Awards First-Ever Grants The Large Hadron Collider (LHC) Theory Initiative, a U.S.-based consortium of theoretical physicists aiming to stimulate and cultivate new young talent in anticipation of the opening of the Large Hadron Collider later this year, announces its 2007 LHC Theory Graduate Fellowship Awards. Administered by The Johns Hopkins University and funded by the National Science Foundation, the $40,000 awards -- being distributed for the first time this year -- will provide selected young theorists with funds to underwrite the costs of their research, including travel and computing needs. Recipients of the 2007 LHC Theory Initiative Graduate Fellowship Awards are Randall Kelly (University of California, San Diego) and Jonathan Walsh (University of Washington). Their research interests include calculations of higher-order corrections both within and beyond the Standard Model, as well as the development of new, improved, simulation tools to confront with data theoretical models. In addition, LHC Theory Initiative Travel Awards, which provide $3,000 for LHC-related travel, were presented to Dai De Chang (Case Western Reserve University), Wei Gong (University of Oregon), David Krohn (Princeton University) and Keith Rehermann (Johns Hopkins University). All six winners are graduate students selected through a national competition. The chair of the selection committee was Fred Olness from Southern Methodist University. "The goal of these fellowships and awards is to stimulate the work of theoretical physicists who will help interpret the treasure trove of data that will emerge from the Large Hadron Collider," said Jonathan Bagger, a member of the LHC Theory Initiative and chair of the Department of Physics and Astronomy at Johns Hopkins. "Our initiative will help the high-energy physics community take full advantage of the LHC."

UW Group Finds Evidence for Lonely Top Quarks

The DZERO experiment has seen evidence for single top quark production at the Tevatron particle accelerator located at Fermilab, just outside of Chicago Illinois. The physics department's Elementary Particle Experimental group played a central role in the observation of single top quark production. Group members involved in DZERO include T. Burnett, G. Watts, A. Garcia-Bellido, H. Lubatti, T. Zhao, and graduate student T. Gadfort. The top quark was discovered in 1995 produced in pairs and its mass was found to be surprisingly heavy -- almost that of a gold atom. It has been the subject of intense study since then: its high mass has led many to speculate that it is associated with the Higgs mechanism responsible for electro-weak symmetry breaking -- one of the great open questions in particle physics. While the strong force produced the discovery signature, it has been known that the top quark could also be produced by the electro-weak force. This production mechanism is known as single-top production because only one top quark is produced in the final state. For the first time we have observed evidence for this production mechanism of the top quark. Single top production also allows us to make the first ever direct measurement of the Vtb matrix element of the CKM quark-coupling matrix. This measurement is just the beginning of an exciting top-quark research program. As we accumulate data we will be able to better probe top quark interactions for evidence of physics beyond the standard model and better constrain the as yet unobserved Standard Model Higgs. Observing single top production is also important because is it one of the last backgrounds to the Standard Model Higgs. Fermilab has issued a press release on this important discovery.

SciDAC Award

The Department of Energy has announced that a University of  Washington team will lead a new $15M project to bring advanced computing resources to bear on the physics of atomic nuclei.  Knowledge in this area is needed for engineering as well as pure science.  Engineering applications of nuclear physics include the design of power reactors, waste burning, and simulations to obviate the need for nuclear testing.  In pure science,  better theory of nuclear properties is needed for understanding of astrophysical processes, particularly concerning the creation of the elements in the stars. An important aspect of the project is to bring advanced computing resources and expertise to bear on the physical questions through the heavy use of the upcoming supercomputers with up to a quarter million processors and capable of operating in the petascale regime (thousands of million of million of operations per second).  It is anticipated that this collaborative effort between computer scientists and nuclear physicists will bring about a dramatic improvement in the accuracy and reliability of theoretical predictions of the nuclear properties.  The project, called "Low-Energy Nuclear Physics National High-Performance Initiative: Building A Universal Nuclear Energy Density Functional",  includes 8 universities and 6 national laboratories, and will extend over 5 years. It is led by George Bertsch and Aurel Bulgac in the Institute for Nuclear Theory and the Department of Physics at the University of Washington.

UW link                             
SciDAC physics link