American Physical Society Division Research Articles

The Fourth International Particle Accelerator Conference

The fourth International Particle Accelerator Conference, IPAC'13, took place at the Shanghai International Conference Center, Shanghai, China from Sunday to Friday, 12 to 17 May, 2013. It was attended by close to 1000 full time delegates from approximately 30 different countries on all continents. Hosted by the Shanghai Institute of Applied Physics (SINAP) and the Institute of High Energy Physics (IHEP), Beijing, it was supported by the Asian Committee for Future Accelerators (ACFA), the American Physical Society Division of Physics of Beams (APS-DPB), the European Physical Society Accelerator Group (EPS-AG), the International Union of Pure and Applied Physics (IUPAP), the Chinese Academy of Sciences (CAS) and the National Natural Science Foundation of China (NSFC). Furthermore, the attendance of over 85 young scientists from all over the world was made possible through the sponsorship of societies, institutes and laboratories worldwide (in alphabetical order): ACFA, APS-DPB, CAS, EPSAG with contributions from ALBA-CELLS, Centro Fermi, CERN, CNRS-IN2P3, DESY, Diamond Light Source, ESRF, GSI, HZB, HZDR, IFIC, JAI, Max Lab, PSI, Synchrotron Soleil and STFC/Cockcroft Institute, and IUPAP. The organizers of IPAC'13 are grateful to all sponsors for their valuable support.

The 14th biennial Center for Turbulence Research Summer Program

This is a brief account of the 14th biennial Summer Program of the Center for Turbulence Research, which was held at Stanford University from June 25 to July 20, 2012. Key accomplishments achieved during the summer program were presented at the conclusion of the program, and a few highlights are reported here. More detailed results are to be reported at the annual American Physical Society–Division of Fluid Dynamics meeting in San Diego, November 18-20, 2012, and in Proceedings of the 2012 Summer Program to be published in December 2012 by the Center for Turbulence Research of Stanford University. A repeating theme of the 2012 Summer Program was applications of the dynamic mode decomposition analysis, which revealed important dynamical information of flow physics. Other new findings are highlighted.

Dynamics of magnetic flux tubes in space and laboratory plasmas

This paper gives a brief summary of topics discussed at a mini-conference on the dynamics of magnetic flux tubes in space and laboratory plasmas. This mini-conference was held as part of the Fall 2005 meeting of the American Physical Society Division of Plasma Physics.

Развитие хаотической адвекции

The concept of chaotic advection was developed some twenty years ago as an outgrowth of work on advection by interacting point vortices. The term “chaotic advection” was first introduced in the title of an abstract for the 35th annual meeting of the American Physical Society (APS) Division of Fluid Dynamics (DFD) in 1982. The main reference, a Journal of Fluid Mechanics paper published in 1984, may be the true “birthdate” of the term. Earlier work from the 1960s by Arnol’d and Henon on advection by steady three-dimensional flows already contained closely related ideas and results but was not widely appreciated. The present paper, based on the 2000 Otto Laporte Memorial Lecture delivered at the 53rd APS/DFD annual meeting, traces these and other precursors and the development of chaotic advection over the past two decades. Some exciting recent developments, such as application to fluid mixing in micro-electromechanical systems (MEMS) and to materials processing, and the introduction of topological methods ...

Mini-conference on plasma turbulence in the corona, heliosphere and interstellar medium

This paper provides a summary of some major physics issues discussed in the Mini-conference on plasma turbulence in the corona, heliosphere and interstellar medium. This is one of two Mini-conferences sponsored by the Topical Group on Plasma Astrophysics held as part of the American Physical Society Division of Plasma Physics Fall 2001 Meeting, 30 October–2 November 2001

Mini-conference on magnetic reconnection in space and astrophysical plasmas

A mini-conference on magnetic reconnection in space and astrophysical plasmas was held as part of the American Physical Society Division of Plasma Physics Fall 2001 Meeting 30 October–2 November 2001. This paper provides a summary of some major physics issues discussed during this mini-conference.

The development of chaotic advection

The concept of chaotic advection was developed some twenty years ago as an outgrowth of work on advection by interacting point vortices. The term “chaotic advection” was first introduced in the title of an abstract for the 35th annual meeting of the American Physical Society (APS) Division of Fluid Dynamics (DFD) in 1982. The main reference, a Journal of Fluid Mechanics paper published in 1984, may be the true “birthdate” of the term. Earlier work from the 1960s by Arnol’d and Hénon on advection by steady three-dimensional flows already contained closely related ideas and results but was not widely appreciated. The present paper, based on the 2000 Otto Laporte Memorial Lecture delivered at the 53rd APS/DFD annual meeting, traces these and other precursors and the development of chaotic advection over the past two decades. Some exciting recent developments, such as application to fluid mixing in micro-electromechanical systems (MEMS) and to materials processing, and the introduction of topological methods of analysis, are highlighted. On balance, chaotic advection is now established as a subtopic of fluid mechanics with wide ramifications and continued promise for theory, experiment and applications.

Putting Antimatter on the Scales

One of the bearing walls of modern physics is that particles of antimatter and those of matter are perfect counterparts, down to their mass. That wall is standing strong, according to new results presented last week at a meeting of the American Physical Society's Division of Atomic, Molecular, and Optical Physics in Santa Fe, New Mexico. The international team has caged a proton and an antiproton in a trap and deduced that they have the same mass to within a part in 10 billion.

Brighter Omens for Giant Reactor?

FUSIONPITTSBURGH- A debate over whether turbulence would cause heat to leak from a prototype fusion reactor--the projected $10 billion International Thermonuclear Experimental Reactor (ITER)--received fresh fuel at a tense session of last week's meeting here of the American Physical Society's division of plasma physics. A new set of calculations suggests that fusion reactors like ITER would leak heat more slowly than predicted by the model that set off the debate last year. But nobody is ready to say that the results put ITER in the clear, as researchers have been unable to pinpoint why the predictions differ under some conditions.

Getting Familiar With the Top Quark

Minneapolis—It was only last year that particle physicists confirmed the existence of the top quark, the heaviest building block of matter. Now they are seeing top quarks by the scores and getting an accurate fix on their mass, physicists reported here at a meeting of the American Physical Society's division of particle and fields. The refined top mass is providing a guidepost to a bigger prize: the still-unseen Higgs boson, a particle that would help explain the array of different masses seen in other elementary particles, one of the major unsolved mysteries of particle physics.

Quantitative BEC Results Reported at DAMOP Meeting

Now that the rantare of simply creating a Bose–Einstein condensate in a dilute atomic gas has died down (see the “Reference Frame” column by Daniel Kleppner on page 11), the leading research groups are proceeding in earnest to map out the properties of their condensates. Four experimental groups reported their latest results in invited talks at a session on Bose–Einstein condensation (BEC) at the meeting of the American Physical Society's Division of Atomic and Molecular Physics (DAMOP) held in Ann Arbor in May.

Physicists Find Windows of Opportunity in Plasmas

The 1500 physicists from Europe, the United States, the Pacific Rim, and the former Soviet Union who gathered in Minneapolis from 7 to 11 November had many messages but one medium: plasmas. As the presentations at the meeting of the American Physical Society's division of plasma physics showed, the windows that laboratory plasmas can provide into space, turbulent liquids, and matter-antimatter interactions are opening wider than ever.

Space science setbacks discussed

Making the best of a difficult situation seemed to be the recurring theme of a forum on the future of U.S. space science held earlier this month at the meeting of the American Physical Society's Division of Plasma Physics in Baltimore, Md. The loss of the space shuttle Challenger has had “immediate and very substantial” effects on space science, according to Jeffrey D. Rosendhal of the Office of Space Science and Applications at the National Aeronautics and Space Administration (NASA), one of four speakers at the forum.

A Theoretical Derivation of Resonant Absorption††This paper was first presented at the 25th Annual Meeting of the American Physical Society Division of Plasma Physics, No. 7-11, 1983, Los Angeles, California

The Problems of resonant absorption in laser-plasma interactions are analyzed by means of a new method. First, we obtain an analytical expression for the electromagnetic field structure of resonant absorption, which is valid for all regions of the coronal plasma and correctly reflects various fundamental features. Then, we derive the absorption coefficient in the form of an elementary function. The results are in excellent agreement with numerical calculations for all angles of incidence. This work extends previous results obtained by solving the wave equation.

Harmonic Emssions From Laser-Produced Plasmas††This paper was first presented at the 25th Annual Meeting of the American Physical Society Division of Plasma Physics, No. 7-11, 1983, Los Angeles, California.

Harmonic generation as a result of resonant absorption in laser-produced plasmas is investigated by considering the steepened plasma density gradients in the vicinity of the critical density. We obtained an efficiency of the second harmonic emission which is in better agreement with experiments than previous theories. The present calculation has also been extended to including the efficiency of the third harmonic emission, the results obtained indicate that at sufficiently high laser intensities, the third harmonic emission generated by the resonant absorption can also be observed.

A look at the future of particle physics

US particle physicists have recently been debating where they will find the most exciting physics and what future facilities will best enable them to pursue it. The dialog intensified last summer at a study sponsored by the American Physical Society Division of Particles and Fields and continued through the Division's annual meeting at the University of Maryland at the end of October. About 150 high‐energy physicists participated in the DPF Summer Study on Particle Physics and Future Facilities, which was held in Snowmass, Colorado (near Aspen), from 28 June to 16 July. Its stated purpose was to assess the physics topics that might be interesting in the future, to explore the limits of technological capabilities and to consider the nature of future facilities for particle physics in the US. Charles Baltay (Columbia University), chairman of the organizing committee, stressed to us that the role of the summer session was to study the physics but not to arrive at any specific conclusions.

Officers

Elected officers of the American Physical Society's Division of High‐Polymer Physics for the 1965–66 term include H. D. Keith, chairman; Elio Passaglia, vice chairman; and W. James Lyons, secretary treasurer. John D. Hoffman and Fraser P. Price were named to three‐year terms on the Executive Committee of the Division.

Society Activities

The annual meeting of the American Physical Society's Division of Solid State Physics was held March 10 to 12 in Cleveland at the Case Institute of Technology and Western Reserve University. The division was informally organized in 1943 by six individuals who formed a committee, and acted (in the words of Frederick Seitz, who spoke at the dinner meeting on March 11) “as spokesmen for the field during the somewhat stormy period in which the Society as a whole was attempting to decide whether to remain a one‐celled organism like a Paramecium or to evolve into something more complex like a starfish or a sea anemone.” The division was formulated and authorized in 1947–48. Roman Smoluchowski served as its first chairman during the 1948–49 term. William Shockley is the new chairman, and A. von Hippel (vicechairman) and S. L. Quimby have taken the place of T. A. Read and S. Siegal, the retiring members of the executive committee. The other members of the committee are A. Lawson and R. Smoluchowski.