bluuebunny/crossref_metadata_2025 huggingface dataset:
Electoral Reform Opens Roads to Presidency for Finnish Women
Authors: Holli Anne Maria
Published: September 2008

This is how political scientist Aili Mari Tripp poignantly highlighted some of the differences between Finnish and U.S. presidential campaigns in an essay on the 2000 presidential elections in Finland. Eight years later, there would be plenty of additional oddities to report, for example, how President Tarja Halonen acquired and happily embraced a new image as a Conan O'Brien look-alike (surely every woman's dream!) and the subsequent meeting between both red-haired personae in her residence during her second-term presidential campaign. On a more serious note, however, the basics of the greater narrative of politics remain the same: That is, since 1994, all three presidential elections in Finland have culminated in a second round in a race between a female and a male candidate for popular support. As a result, Foreign Minister Tarja Halonen was elected as the first woman president of the country in 2000 and reelected in 2006.
Periodic components of water storage changes from GRACE and global hydrology models
Authors: Schmidt R. , Petrovic S. , Güntner A. , Barthelmes F. , Wünsch J. , Kusche J.
Published: September 2008

We analyze spatiotemporal variations of surface mass anomalies induced by hydrological mass redistributions at the Earth's surface. To this end, we use a suite of global hydrological models as well as products from the Gravity Recovery and Climate Experiment (GRACE) satellite mission. As a novelty we identify dominating periodic patterns that are not restricted to the fundamental annual frequency and its overtones, using a method that combines conventional empirical orthogonal functions (EOF) analysis with a determination of sine waves of arbitrary periods from the principal components. We assess the significance of the derived spectra in view of correlated errors of the GRACE data by means of a Monte Carlo technique. This allows us to create filtered GRACE time series including only the significant terms, which will serve for basin‐specific calibration of hydrological models with respect to the dominant periodic water storage variations. The study reveals that besides dominating annual signals, semiannual (found only in a few basins), and also long‐periodic waves in the range of 2.1 to 2.5 years contribute to periodic water storage variations. An interpretation and a preliminary explanation of these spectra is included. Comparisons of the spectra obtained from GRACE and global hydrological models exhibit in many river basins a systematic advance of the phases of annual terms of the hydrological models as compared to GRACE in the range of 1 to 6 weeks. This indicates deficiencies of the hydrological models with regard to runoff routing in the river network and/or water retention in lakes and wetlands.
On the rise of turbulent plumes: Quantitative effects of variable entrainment for submarine hydrothermal vents, terrestrial and extra terrestrial explosive volcanism
Authors: Carazzo G. , Kaminski E. , Tait S.
Published: September 2008

The maximum height reached by a turbulent plume rising in a stratified environment is a key tool to estimate the flux released at its source, particularly for large‐scale flows because flux can often be very hard to measure directly. This height is known to be mainly controlled by the stratification of the ambient fluid, source buoyancy flux, and the efficiency of turbulent mixing between the plume and the external fluid. The latter effect has been only superficially explored in spite of its fundamental control on the dynamics. Here we show that commonly used one‐dimensional models incorporating a constant entrainment coefficient do not provide satisfying predictions. We propose a new model allowing for variable entrainment which gives excellent predictions of maximum heights reached by laboratory plumes in stratified environments. We then apply our formalism to natural plumes produced by explosive volcanic eruptions under terrestrial, paleo‐Martian, and Venusian conditions and by submarine hydrothermal activity at mid‐ocean ridges. Source mass discharge rates deduced from maximum volcanic column heights for terrestrial eruptions are found to be greater than those estimated with the commonly used constant entrainment parameterization by a factor of 2. In the paleo‐Martian atmosphere, existing models overestimate plume heights by 14–27%. In the current atmosphere of Venus, the maximum height reached by a volcanic plume is also found to be smaller than previously estimated for large eruption rates. The source heat flux released by the TAG field (Atlantic Ocean) deduced from several submarine hydrothermal plumes is found greater by a factor 3 with our model.
Simulation and parameterization of the turbulent transport in the hurricane boundary layer by large eddies
Authors: Zhu Ping
Published: September 2008

Hurricane boundary layer (HBL) processes, especially the structure of the coherent large eddy circulations (LECs) and their induced vertical transport, are not well understood. This paper introduces a large eddy simulation (LES) framework in a weather hindcasting mode developed from a multiple scale nested Weather Research and Forecasting (WRF) model. Using the WRF–LES, this study investigated the structure of the HBL LECs and the associated vertical transport during the landfall of Hurricane Ivan (2004). The simulation shows that the HBL LECs exist in a mean stable environment and consist of well‐defined updraft and downdraft. Statistically, the HBL LECs are only slightly skewed with the updrafts and downdrafts relatively evenly distributed spatially. The inversion base basically envelopes the upper boundary of LECs. The trough in between two adjacent LECs is where most entrainment takes place, whereas the crest of the LECs is where boundary layer air detrains out of the HBL. In such a way, LECs directly connect the surface, the HBL, and the main body of a hurricane vortex and enhance the exchange of energy, moisture, and momentum between them. It is found that the current boundary layer schemes significantly underestimate the resolved turbulent fluxes due to the fact that the effects of LECs have not been included in the parameterizations. On the basis of the statistical structure of LECs simulated by the WRF–LES, this paper proposes a conceptual updraft–downdraft model that can potentially be implemented in weather forecasting models to parameterize the fluxes induced by the HBL LEC transport.
The formation and stability of the superoxide radical (O2−) on rock‐forming minerals: Band gaps, hydroxylation state, and implications for Mars oxidant chemistry
Authors: Zent Aaron P. , Ichimura Andrew S. , Quinn Richard C. , Harding Heather K.
Published: September 2008

We have examined the generation and stability of O2− on TiO2 and albite, a common Na feldspar. We were not able to produce thermally stable superoxide on albite, in contrast to the results of Yen et al., who reported the generation of O2− that was stable up to 200°C on labradorite, another common feldspar. The superoxide radical did form under UV irradiation at 77 K on albite that was not dehydrated but decayed rapidly at room temperature. On dehydrated albite, no superoxide signal was observed. We studied the kinetics of O2− decomposition on hydrated albite and derived an activation energy, Ea = 15.2 kJ/mol. Assuming pseudo first‐order kinetics, a simple thermal model of Mars' regolith demonstrates that the surface O2− population does not go to zero overnight; superoxide extinction at the surface is only complete when the seasonal CO2 cap covers the surface and surface photolysis is inhibited. Depending on the specific quantum efficiency of the e−/h+ generation process, a finite, non‐equilibrium population of O2− should be observable on Martian surface materials throughout the Martian year. However, on the basis of our inability to generate stable O2− on hydrated albite via direct UV irradiation, we do not believe that this mechanism is capable of explaining the O2 release in the Viking Gas Exchange (GEx) results, since O2 release in that case was observed even after samples had been stored for 143 sols in the dark at 10°C, then heated to 145°C for 3 hours. At least two other potential pathways to the generation of O2− are identified in this article. The first possibility is that metal oxides common on the Martian surface, particularly hematite, may be photoactive on Mars and play a role analogous to TiO2 in surface catalysis. Secondly, we found that superoxide that formed during the sorption or drying of a 1% H2O2 solution on TiO2, and potentially other oxides seems to be stable indefinitely.
Flow and bathymetry in sharp open‐channel bends: Experiments and predictions
Authors: Zeng Jie , Constantinescu George , Blanckaert Koen , Weber Larry
Published: September 2008

This paper focuses on experiments and simulations conducted in very sharp open‐channel bends with flat and equilibrium bathymetry, corresponding to the initial and final phases of the erosion and deposition processes, respectively. The study of flow in curved open bends is relevant for flow in natural river configurations, as most river reaches are not straight. The configuration considered in the present work was designed as a test case in which the role of the cross‐sectional flow is more severe than in meandering natural river reaches (radius of curvature of the channel is close to the channel width) and, thus, can serve for validation of numerical models used to predict flow and sediment transport in river engineering applications. This paper presents detailed new experimental data on the equilibrium bathymetry as well as depth‐averaged distributions, vertical profiles, and cross‐sectional patterns of the streamwise velocity, the cross‐stream circulation, streamwise vorticity, and the turbulent kinetic energy at the initial and final stages of the erosion and deposition processes. The numerical simulations are performed using a three‐dimensional nonhydrostatic RANS model for flow, sediment transport, and bathymetry, which employs fine meshes, accounts for the effect of small bed forms, and avoids the use of the law of the wall. The model predicts, rather accurately, the distribution of the streamwise velocity, the cross‐stream circulation, and the turbulent kinetic energy in the simulations conducted with a fixed (flat and deformed bed corresponding to equilibrium conditions) prescribed bathymetry. In the case of a simulation conducted with loose bed, the model predicts satisfactorily the main features of the bathymetry at equilibrium conditions, despite the fact that including the interaction between the flow and the bathymetry increases the overall uncertainty in the model predictions. Results indicate that both improvements in the level of turbulence modeling and in the modeling of the sediment transport would allow further improvement in the predictive capabilities of morphodynamic models.
Reduced ice thickness in Arctic Transpolar Drift favors rapid ice retreat
Authors: Haas Christian , Pfaffling Andreas , Hendricks Stefan , Rabenstein Lasse , Etienne Jean‐Louis , Rigor Ignatius
Published: September 2008

Helicopter‐borne electromagnetic sea ice thickness measurements were performed over the Transpolar Drift in late summers of 2001, 2004, and 2007, continuing ground‐based measurements since 1991. These show an ongoing reduction of modal and mean ice thicknesses in the region of the North Pole of up to 53 and 44%, respectively, since 2001. A buoy derived ice age model showed that the thinning was mainly due to a regime shift from predominantly multi‐ and second‐year ice in earlier years to first‐year ice in 2007, which had modal and mean summer thicknesses of 0.9 and 1.27 m. Measurements of second‐year ice which still persisted at the North Pole in April 2007 indicate a reduction of late‐summer second‐year modal and mean ice thicknesses since 2001 of 20 and 25% to 1.65 and 1.81 m, respectively. The regime shift to younger and thinner ice could soon result in an ice free North Pole during summer.
Smoothing of climate time series revisited
Authors: Mann Michael E.
Published: September 2008

We present an easily implemented method for smoothing climate time series, generalizing upon an approach previously described by Mann (2004). The method adaptively weights the three lowest order time series boundary constraints to optimize the fit with the raw time series. We apply the method to the instrumental global mean temperature series from 1850–2007 and to various surrogate global mean temperature series from 1850–2100 derived from the CMIP3 multimodel intercomparison project. These applications demonstrate that the adaptive method systematically out‐performs certain widely used default smoothing methods, and is more likely to yield accurate assessments of long‐term warming trends.
Addressing model bias and uncertainty in three dimensional groundwater transport forecasts for a physical aquifer experiment
Authors: Kollat J. B. , Reed P. M. , Rizzo D. M.
Published: September 2008

This work contributes a combination of laboratory‐based aquifer tracer experimentation and bias‐aware Ensemble Kalman Filtering (EnKF) to demonstrate that systematic modeling errors (or bias) in source loading dynamics and the spatial distribution of hydraulic conductivity pose severe challenges for groundwater transport forecasting under uncertainty. The impacts of model bias were evaluated using an ammonium chloride tracer experiment conducted in a three dimensional laboratory tank aquifer with 105 near real‐time sampling locations. This study contributes a bias‐aware EnKF framework that (i) dramatically enhances the accuracy of concentration breakthrough forecasts in the presence of systematic, spatio‐temporally correlated modeling errors, (ii) clarifies in space and time where transport gradients are maximally impacted by model bias, and (iii) expands the size and scope of flow‐and‐transport problems that can be considered in the future.
Numerical analysis of ionosphere disturbances and Schumann mode splitting in the Earth‐ionosphere cavity
Authors: Navarro E. A. , Soriano A. , Morente J. A. , Portí J. A.
Published: September 2008

The variability of ionosphere properties plays an important role in the Schumann resonances (SR), amplitudes, frequencies, and Q factor. Therefore, as atmosphere ionization is related to solar activity, SR could be devised as a source of indirect parameters that locally from the surface of the Earth could provide space weather information. A proper understanding of this link to SR parameters can be obtained through finite difference time domain (FDTD) simulations, specifically with the numerically obtained modes and frequencies that relate frequency shifts to the day‐night asymmetry and polar inhomogeneities. Day‐Night asymmetry is observed to have a minor influence in SR; however, large changes are deduced from polar nonuniformities associated to Solar Proton Events (SPE) and X‐ray bursts. The field volume distribution of the modes provides the understanding of the SR variability, related to the altitude and latitude of the ionization phenomenon.
Automatic infrasonic signal detection using the Hough transform
Authors: Brown David J. , Whitaker Rodney , Kennett Brian L. N. , Tarlowski Chris
Published: September 2008

The Hough transform is a mathematical device that allows the retrieval of parametric curve information from binary‐pixelated data in the presence of noise. This slope‐intercept transform maps each point in the image space S into a straight line in parameter space P and has the very useful property that all points in S that lie along the same straight‐line map to the same number of straight lines in P with a common intersection point. Thus with a suitable counting procedure, the problem of extended straight‐line detection in noisy pixelated data becomes one of local peak finding, a problem that may be substantially more tractable. In this study, an algorithm that utilizes the Hough transform for the detection of signals in International Monitoring System style infrasonic array data by seeking periods of constant backazimuth that are associated with coherent acoustic signals is described. A system of synthetic signal implants is used to assess the performance of the detection algorithm by generating a set of pseudo Receiver Operator Characteristic curves. A feature of the detection algorithm is the ability to accommodate full three‐dimensional array geometry.
Critical Thinking as Disciplinary Practice
Authors: Yanchar Stephen C. , Slife Brent D. , Warne Russell
Published: September 2008

Critical thinking in psychology has traditionally focused on method-centered tasks such as the assessment of method use, data analysis, and research evidence. Although helpful in some ways, this form of critical thinking fails to provide resources for critically examining the scientific analytic foundation on which it rests and, when used exclusively, prohibits sufficiently critical analysis of theory and research. An alternative view of critical thinking—that emphasizes the identification and evaluation of implicit theoretical assumptions—is advocated. It is suggested that this alternative approach improves on method-centered approaches by addressing not only implicit assumptions but also rule-following concerns. This approach is intended to facilitate innovation and the production of scholarly work in ways that incorporate relational values such as dialogue, care, and respect. Finally, this alternative form of critical thinking is described as a theoretically situated, open, and evolving conception of critique that should itself be continually reanalyzed and refined, particularly in response to the evolving nature and needs of the field.
“Save Angels Perhaps”: A Critical Examination of Unconscious Thought Theory and the Deliberation-Without-Attention Effect
Authors: González-Vallejo Claudia , Lassiter G. Daniel , Bellezza Francis S. , Lindberg Matthew J.
Published: September 2008

Based on Unconscious Thought Theory (UTT) and a series of experimental and correlational studies, Dijksterhuis and his colleagues conclude that when making complex choices/decisions, conscious thought—deliberation while attention is directed at the problem—leads to poorer choices/decisions than “unconscious thought”—deliberation in the absence of conscious attention directed at the problem. UTT comprises six principles said to apply to decision making, impression formation, attitude formation and change, problem solving, and creativity. Because the implications of UTT for psychological research and theory are considerable, the authors critically examined these six principles (and the studies used to support them) in light of the extant scholarship on unconscious processes, memory, attention, and social cognition. Our examination reveals that UTT is a theory of the unconscious that fails to take into account important work in cognitive psychology, particularly in the judgment and decision making area. Moreover, established literatures in social psychology that contradict fundamental tenets of UTT and its empirical basis are ignored. The authors conclude that theoretical and experimental deficiencies undermine the claims of the superiority of unconscious thinking as portrayed by UTT.
Predicting Protein-Disease Relationships Using Sequence, Physicochemical Properties, and Molecular Function Information
Authors: Radivojac Predrag , Peng Kang , Clark Wyatt , Peters Brandon , Mohan Amrita , Boyle Sean , Mooney Sean
Published: August 2008

One of the most important tasks of modern bioinformatics is the development of computational tools that can be used to understand and treat human disease. To date, a variety of methods have been explored and algorithms for predicting whether a protein is involved in disease are gaining in their utility. Here, we describe an algorithm for detecting protein-disease associations based on the human protein-protein interaction network, known gene-disease associations, protein sequence, and protein functional information at the molecular level. Our method, PhenoPred ("www.phenopred.org":www.phenopred.org), is supervised: first, we map each protein onto the spaces of disease and functional terms based on distance to all annotated proteins in the protein interaction network. We also encode sequence, function, physicochemical, and predicted structural properties, such as secondary structure and flexibility. We then train support vector machines to detect a protein’s disease function for a number of terms in Disease Ontology (DO). We provided evidence that, despite the noise/incompleteness of experimental data and unfinished ontology of diseases, identification of candidate genes and proteins can be successful even when a large number of candidate disease terms are predicted on simultaneously.
New light on Novaya Zemlya polar mirage
Authors: Lubkin Gloria B.
Published: September 2008

While seeking a Northeast Passage to the Orient, the explorer Willem Barents and his crew were stranded for the winter at Novaya Zemlya (76°12'N). During the perpetual night of their arctic winter, one noontime in January 1597 the explorers were astonished to see the Sun appear two weeks sooner than expected at that latitude. At the time, the Sun's actual position was still about 5° below the geometrical horizon.
The road to superconducting materials
Authors: Hulm John K. , Kunzler J. Eugene , Matthias Bernd T.
Published: September 2008

In the golden research period immediately following World War II, the three of us took up research work in cryogenics and superconductivity. We were fortunate enough to make some discoveries in superconducting materials that laid the groundwork for new avenues of technological development. In this article, we present our recollections of the history of these discoveries and some of the human events surrounding them. As is well known, scientific progress rarely takes the logical paths usually portrayed in scientific journals; much of it begins with chance encounters or random events. We shall mention a few of the unusual factors that affected our work and some of the people who influenced our thinking.
Deep redshift survey of galaxies suggests million-Mpc3 void
Authors: Schwarzschild Bertram M.
Published: September 2008

Surveying the redshifts of bright galaxies out to 800 megaparsecs, a group of astronomers has found preliminary evidence for the existence of a gigantic void—a million-cubic-megaparsec volume devoid of bright galaxies—in the northern sky. In a recent Astrophysical Journal Letter, Robert Kirshner (University of Michigan), Augustus Oemler (Yale), Paul Schechter (Harvard–Smithsonian and Kitt Peak) and Stephen Shectman (Mount Wilson and Las Campanas Observatories) report that their deep redshift surveys of three small angular regions in the constellation Boötes show identical 6000-km/second gaps in the velocity distribution of galaxies down to 16th magnitude. The three sampled regions, each 1.4° square, form a roughly equilateral triangle on the celestial sphere, about 35° on a side. Assuming that the entire triangular region will ultimately prove to be “empty” in this same 6000-km/second velocity interval, centered at 15 000 km/second, one would deduce the existence of a void more than 100 megaparsecs across, about 300 Mpc (109 light years) distant from us.
Supermultiplets in doubly excited atoms
Authors: Levi Barbara G.
Published: September 2008

Take an excited hydrogen atom, add a second excited electron, and you change the calculation of energy levels from an easy problem to a formidable task. In such doubly excited atoms, the dominance of electron correlations considerably alters the single-particle shell structure. Alternative formulations of the electronic states in terms of hyperspherical coordinates have greatly elucidated the angular and radial correlations. That progress was recently boosted by the insight from dynamical group theory: A supermultiplet classification gives striking order to the energy spectrum and predicts which electron states become mixed. This supermultiplet classification visually depicts the doubly excited atom as a linear triatomic molecule having the electrons across the nucleus from one another and exhibiting collective rotational and bending motions. This new view is compatible with that of the hyperspherical approach. All the varying perspectives were discussed last month at the meeting of the APS Division of Electron and Atomic Physics in New York.
Crystal Ball to move from SLAC to DESY
Authors: Schwarzschild Bertram M.
Published: September 2008

The German Electron Synchrotron laboratory (DESY, Hamburg) and SLAC have agreed to a unique intercontinental transfer of a major high-energy-physics detector facility. After more than three years of fruitful operation at SPEAR, the older of the two electron–positron storage rings at SLAC, the “crystal-ball” particle detector will be moved in June to DORIS, SPEAR's opposite number at DESY. The 730 sodium-iodide crystals that make up the seven-foot-diameter hollow crystal ball provide extra-ordinary energy resolution for high-energy photons (PHYSICS TODAY, July 1981, page 21).
Physicists and astronomy—Will you join the dance?
Authors: Harwit Martin
Published: September 2008

Twenty-five years ago when I was a graduate student in physics, I was drafted into the Army and sent to Eniwetok in the Marshall Islands. There was plenty of spare reading time for an army private on this tiny atoll, and I had taken along a paperback copy of Fred Hoyle's Frontiers of Astronomy. Hoyle made astronomy exciting and I began to wonder whether I might find a way to enter the field.
Fifty years of physics education
Authors: French A. P.
Published: September 2008

Physics education isn't what it was 50 years ago. The most obvious changes have been quantitative: In 1930 in all of the US about 1000 students received bachelors' degrees in physics; about 200, masters' degrees; and about 100, PhDs. In 1980 the corresponding numbers were 4500, 1500 and 1000; and in the peak years around 1970 the figures were about 6000, 2500 and 1500 (see page 52). These large increases, corresponding to a factor of ten or more for graduate degrees, also point to the extent to which physicists have become essential to the technical development of our society and to the increased acceptance (at least in principle) of the idea that every citizen, in today's technological society, ought to have some knowledge of science in general and of physics in particular. Few would go so far as to embrace C.P. Snow's view that no person can be considered truly educated without knowing the second law of thermodynamics. (“My partner doesn't even know the first law,” said Michael Flanders, in mock disgust, in the show “At the Drop of a Hat.”) But many would give vigorous assent to what Henry Perkins said in 1969: “As we are living in a scientific age, physics is just as much of a cultural subject as the older humanities. Not to know something about the basic principles of mechanics, electricity and, at least, to have a smattering of atomic structure stamps the modern man as only half-educated, just as ignorance of Latin and Greek indicated relative illiteracy to our forefathers.”
The development of field theory in the last 50 years
Authors: Weisskopf Victor F.
Published: September 2008

This article is devoted to the development of quantum field theory, a discipline that began with quantum electrodynamics, which was born in 1927 when P. A. M. Dirac published his famous paper “The Quantum Theory of the Emission and Absorption of Radiation.” Figure 1 reproduces the first page. Note that it was communicated by Niels Bohr himself. Also note the second and third sentences. The latter is an understatement indeed: Nothing had been done up to this time on quantum electrodynamics.
Physics funding—the evolving federal role
Authors: Piore Emanuel R.
Published: September 2008

The role of the Federal government in support of physics has altered and grown over the last fifty years. In this article I will review the evolution of this role within the context of four time periods: about 1930 to 1940, 1940 to 1945 (World War II), 1945 to the present (post World War II); the fourth period is on the horizon as the administration in Washington strives for a balanced budget.
New techniques of hyperfine spectroscopy
Authors: Redi Olav
Published: September 2008

The decade of 1965–1975 saw a revolution in optical spectroscopy, culminating in the introduction of lasers into high-resolution spectroscopy. Several laboratories immediately put the dye laser to good use for nuclear physics, by using it to measure hyperfine structures and isotope shifts. These developments have produced new, interesting, and at times unexpected, results. Currently, the main motivation of these studies is to understand the behavior of the nuclear charge distribution as the number of neutrons is varied. The required data on isotope shifts for long chains of stable and radioactive species, which until recently existed only for mercury and thallium, are now becoming available for other elements. Experiments are now extending the isotope-shift measurements by “off-line” techniques to nuclei with half lives greater than about 10 minutes, and by “on-line” techniques with accelerators and isotope separators to nuclei with half-lives in the second and sometimes millisecond ranges. The following article by Hans Schuessler concentrates on on-line techniques applied to nuclei far from the region of stability.
Science, technology and human rights
Authors: Brown George E.
Published: September 2008

Human rights do not simply consist of civil and political liberties; these rights are only part of the picture. There are also economic, social and cultural rights. These two sets of human rights are codified in the Universal Declaration of Human Rights of the United Nations and its two instrumental covenants: The International Convenant on Civil and Political Rights and the International Covenant on Economic, Social and Cultural Rights. The regional counterpart is the Organization of American States' American Convention on Human Rights. Just about every issue we deal with in Congress has a human rights component. That, I believe, is also true of science.
E Pluribus Boojum: the physicist as neologist
Authors: Mermin N. David
Published: September 2008

I know the exact moment when I decided to make the word “boojum” an internationally accepted scientific term. I was just back from a symposium at the University of Sussex near Brighton, honoring the discovery of the superfluid phases of liquid helium-3, by Doug Osheroff, Bob Richardson, and Dave Lee. The Sussex Symposium took place during the drought of 1976. The Sussex downs looked like brown Southern California hills. For five of the hottest days England has endured, physicists from all over the world met in Sussex to talk about what happens at the very lowest temperatures ever attained.
Wiggler and undulator magnets
Authors: Winick Herman , Brown George , Halbach Klaus , Harris John
Published: September 2008

To scientists using vacuum ultraviolet and x rays the most important characteristics of an ideal radiation source would be a high intensity within a small solid angle and a high intensity within a small wavelength interval, both extending over a broad range of wavelengths. High spatial brightness (large flux within a small solid angle) permits the delivery of a large number of photons per second to a small sample. High spectral brightness (large flux within a narrow wavelength interval) is essential for high-resolution spectroscopy. A high-power tunable vuv and x-ray laser would be ideal, but unfortunately such a laser does not yet exist. Conventional vuv sources (such as gas-discharge lamps) and x-ray sources (such as electron-impact x-ray tubes) can produce a large flux of radiation, most of which is indeed within a narrow bandwidth at particular fluorescent lines. However, the flux is diffused over a large solid angle and the wavelength is fixed. The continuum radiation from these sources is less intense than the narrow fluorescence peaks by about four orders of magnitude. Other sources exist, such as laser plasma sources and sliding-spark devices, that provide more intense continuum radiation but have other limitations, such as low repetition rate, limited spectral range and attendant debris.
Catalysis of carbon gasification
Authors: Schwarzschild Bertram M.
Published: September 2008

The conversion of carbon to its oxide gases or methane, by interaction with oxygen, steam, hydrogen or carbon dioxide, are reactions of great practical importance. The oxidation of carbon to CO2 and CO provides much of mankind's heat and power, and the formation of “syngas” (a mixture of carbon monoxide and hydrogen) by steam gasification of carbon is an important step in the conversion of coal to synthetic petroleum (PHYSICS TODAY, August 1978, page 32). These reactions, together with the hydrogenation of carbon to form methane, and its interaction with CO2 to form CO, are the principal gasification reactions of carbon.
New synchrotron lab in Hamburg
Authors: Schwarzschild Bertram M.
Published: September 2008

The electron synchrotron and the e+e− storage ring DORIS at the German Electron-Synchrotron laboratory DESY, in Hamburg, have been providing experimenters with synchrotron radiation beams for more than a decade. With the increased demand for synchrotron radiation sources in recent years, and the transfer of high-energy-physics concentration at DESY from DORIS to the new, more energetic e+e− storage ring PETRA, it was decided at the end of 1977 to expand considerably the synchrotron radiation capabilities of DORIS. The recent ceremonial dedication of the new Hasylab marked the realization of this decision.
Fractionally charged solitons
Authors: Levi Barbara G.
Published: September 2008

Move over, quarks. Make room for solitons with fractional charges. These newcomers have surfaced in theories from two distinct branches of physics—relativistic field theory and condensed-matter physics. The appearance of solitons (solitary wave solutions to nonlinear problems) in a wide range of physics problems is increasingly common, but their association with non-integer quantum numbers is a new feature. The analogous mathematical structure of the theories that show this feature is especially appealing to particle theorists because the predictions of the condensedmatter model are more amenable to experimental verification than are those of the more abstract field theories.
Low temperature science—what remains for the physicist?
Authors: Richardson Robert C.
Published: September 2008

Seldom does one remember reading a particular magazine article after twenty years. However, there is an article I have never forgotten, probably because of the discussion it provoked among me and my fellow graduate students at Duke University. I now want to respond to that article.
Pure Physics—a costly vitality and a restricted limelight
Authors: Pippard Brian
Published: September 2008

I am delighted to find that someone actually remembers my 20-year-old after-dinner talk, even if Robert Richardson has only exhumed its corpse to comment adversely on its state of preservation. There is much truth in what he says; in particular, when I suggested the possibility that the excitement of physics might run out after 15 or 25 years I did not guess that funds would be found to equip solid-state laboratories on the scale we now see in dozens of universities. At that time, post-war austerity in Britain had not yet entirely given way to the temporary euphoria of the sixties. In addition, of course, the astonishing development of integrated circuits and the dramatic reduction in the cost of instrumentation have opened up new fields that otherwise would have remained inaccesible. So there is life in the old dog yet, and we may expect to see a reasonable proportion of our brightest young minds attracted into physics for some time to come.
Creativity and ways of thinking: the Japanese style
Authors: Kikuchi Makoto
Published: September 2008

The other day I asked a friend of mine, a Frenchman who is the executive officer of a large, well-known company, what were his first impressions of Japanese people and society. “For me,” he said, “Japanese society is full of contradictions. One day I saw Japanese golfers almost running around the golf course, and this fitted the descriptions of Japanese people I had heard and read. But another time, when I was leaving Japan from Narita International Airport, I found that the Japanese official at the emigration counter was doing his work very, very slowly.”
30-femtosecond light pulses at Bell Labs
Authors: Schwarzschild Bertram M.
Published: September 2008

The development of continuously pumped, mode-locked dye lasers in the early 1970s made possible the first production of sub-picosecond optical pulses in 1974. For the remainder of the decade, attempts to generate significantly shorter pulses of light were not particularly successful. Two new developments reported early last year have now been brought together by a group at Bell Labs to produce optical pulses only 30 femtoseconds long—3×10−14 seconds, or 14 cycles of 6200-Å red light.
Lasers and physics: a pretty good hint
Authors: Schawlow Arthur L.
Published: September 2008

In the early years of lasers, it was common for popular accounts to refer to the laser as “a solution looking for a problem.” That description was sometimes even attributed to me, as though I have tried to point out clearly that I did not believe it. Indeed, any comicstrip artist could think of lots of “real” uses, such as drilling tunnels through mountains, or shooting down Klingons a million miles away. But for such important applications, the capabilities of real lasers were—and still are—pathetically inadequate. For these and many other problems lasers did not provide solutions, but they did give a new and promising place to look for attainable devices that could give answers to worthwhile problems.
Maria Goeppert-Mayer—two-fold pioneer
Authors: Sachs Robert G.
Published: September 2008

When in 1963 she received the Nobel Prize in Physics, Maria Goeppert Mayer was the second woman in history to win that prize—the first being Marie Curie, who had received it sixty years earlier—and she was the third woman in history to receive the Nobel Prize in a science category. This accomplishment had its beginnings in her early exposure to an intense atmosphere of science, both at home and in the surrounding university community, a community that provided her with the opportunity to follow her inclinations and to develop her remarkable talents under the guidance of the great teachers and scholars of mathematics and physics. Throughout her full and gracious life, her science continued to be the theme about which her activities were centered, and it culminated in her major contribution to the understanding of the structure of the atomic nucleus, the spin–orbit-coupling shell model of nuclei.
How long does the tau lepton live?
Authors: Levi Barbara G.
Published: September 2008

The often-quoted remark of I. I. Rabi, made when the muon was discovered—“Who ordered that?”—is again an apt commentary about the third charged lepton to be found, the tau. A recent experiment, by Gary Feldman, George Trilling and their collaborators at the PEP electron-positron collider at SLAC has determined the lifetime of the tau. They find it to be (4.6±1.9)×10−13 sec, a value entirely consistent with the universality of the weak interaction. That is, the weak interaction between the tau and other particles appears, within experimental limits, to be the same as that of the electron and muon. They're all spin-1/2, charged, pointlike particles, differing only in mass: the electron with 0.511003 MeV, the muon with 105.6595 MeV and the tau with 1782 MeV.
The solar cycle
Authors: Newkirk Gordon , Frazier Kendrick
Published: September 2008

Nearly 140 years have elapsed since the German apothecary and amateur astronomer Samuel Heinrich Schwabe reported discovery of the solar cycle. “From my earlier observations,” Schwabe wrote in 1843, “it appears that there is a certain periodicity in the appearance of sunspots and this theory seems more and more probable from the results of this year.” Schwabe had been looking for new planets crossing the Sun's disk. The day-to-day records of sunspots he kept for 18 years as part of that search led him to realize that solar behavior is cyclic.
Dinosaur extinction due to asteroid?
Authors: von Foerster Thomas
Published: September 2008

Recent developments appear to confirm what at first seemed an outrageous idea: A meteorite or asteroid a few kilometers in diameter hit Earth about 65 million years ago and caused a major wave of biological extinctions.
Phases and phase transitions
Authors: Litster J. David , Birgeneau Robert J.
Published: September 2008

In this first sentence of his seminal book “The Physics of Liquid Crystals,” Pierre Gilles de Gennes has succinctly stated the appeal that liquid crystals have for all of us working in this field. The term “liquid crystal,” in fact, refers to a number of distinct states of matter that have structural order intermediate between that of conventional liquids and solids.
Lyotropic liquid crystals
Authors: Pershan Peter S.
Published: September 2008

In mixtures of soap and water, the special properties of soap molecules cause them to form clusters—and clusters of clusters—in a variety of interesting geometrical shapes. Some of these aggregates are liquid crystals, known as lyotropic, which are quite different from thermotropic liquid crystals, the focus of most of the work described in this issue of PHYSICS TODAY. Lyotropic liquid crystals are now receiving a great deal of scientific and technological attention because of the way they reflect the unique properties of their constituent molecules.
Hunting neutron–antineutron oscillation
Authors: Schwarzschild Bertram M.
Published: September 2008

When Murray Gell-Mann and Abraham Pais predicted in 1955 that the K0 meson should exhibit an oscillating probability for metamorphosis into its antiparticle, the K̄0, they cited the neutron as a counterexample. The conservation of baryon number, they pointed out, would prevent the neutron–antineutron analog of neutral-kaon oscillation. But nowadays, with grand unified theories of the elementary particles very much in favor, all bets based on baryon-number conservation are off. A prodigious experimental effort (PHYSICS TODAY, January 1980, page 17) attests to the widespread expectation that proton decay will be seen with a lifetime of about 1031 years.
Solid electrolytes—the beta aluminas
Authors: Bates John B. , Wang Jia-Chao , Dudney Nancy J.
Published: September 2008

Electrolytes conduct electricity by the movement of ions, whereas metals conduct by the flow of electrons. Until recently, almost all electrolytes known to have high conductivities were liquids, such as molten salts or aqueous solutions of salts. But research over the last twenty years has uncovered many solid electrolytes—substances that have a high ionic conductivity even though they are insulators to the flow of electrons. Physicists often call these solids “superionic conductors” because a number of the compounds have electrical conductivities comparable with those of liquid electrolytes. (But we will avoid this term to prevent a possible mistaken identification with superconductors.)
How I created the theory of relativity
Authors: Ono Yoshimasa A.
Published: September 2008

It is known that when Albert Einstein was awarded the Nobel Prize for Physics in 1922, he was unable to attend the ceremonies in Stockholm in December of that year because of an earlier commitment to visit Japan at the same time. In Japan, Einstein gave a speech entitled “How I Created the Theory of Relativity” at Kyoto University on 14 December 1922. This was an impromptu speech to students and faculty members, made in response to a request by K. Nishida, professor of philosophy at Kyoto University. Einstein himself made no written notes. The talk was delivered in German and a running translation was given to the audience on the spot by J. Ishiwara, who had studied under Arnold Sommerfeld and Einstein from 1912 to 1914 and was a professor of physics at Tohoku University. Ishiwara kept careful notes of the lecture, and published his detailed notes (in Japanese) in the monthly Japanese periodical kaizo in 1923; Ishiwara's notes are the only existing notes of Einstein's talk. More recently T. Ogawa published a partial translation to English from the Japanese notes in Japanese Studies in the History of Science.
Spontaneous magnetization in He3-B
Authors: Lubkin Gloria B.
Published: August 2008

A Finnish-Soviet collaboration has found that when they rotate the B phase of superfluid He3, the vortices develop a ferromagnetic core. This magnetization appears suddenly at the same temperature at which the experimenters also observe a phase transition in the structure of the vortex core. The presentation of these results at the International Symposium on Quantum Fluids and Solids held at Sanibel Island last April has stimulated new theoretical studies of the vortex structure. (See the story on page 21 for other results concerning He3-B presented at the same meeting.) One of the more intriguing possibilities is that the mechanism for the spontaneous magnetization in rotating superfluid helium is similar to one previously proposed for rotating neutron stars.
Nuclear spectroscopy
Authors: Ajzenberg-Selove Fay , Warburton Ernest K.
Published: August 2008

Nuclear spectroscopy can be defined as the study of how nuclei absorb and emit energy. It is particularly concerned with the properties of individual levels such as energy, angular momentum (spin), isospin (the embodiment of the basic equivalence of neutrons and protons), magnetic and electric moments and transition rates and so forth. Our knowledge of these properties has increased rapidly and dramatically since 1945. This nearly exponential advance has occurred because of tremendous technical advances in equipment, in experimental methods, and in analyzing experimental data. Figure 1 shows one example of the sort of spectrometers available to nuclear physicists today. The use of the computer in analysis has been especially important in the last 15 years. In this article we will try to convey a feeling for the diversity and sophistication of present-day nuclear spectroscopy; we will concentrate on those areas where in recent years the most progress has been made in our understanding of the properties of nuclear levels.
Newly discovered pulsar is 20 times faster than Crab pulsar
Authors: Schwarzschild Bertram M.
Published: August 2008

Of the more than three hundred known radio pulsars in our galaxy, the most recently discovered is surely the strangest. On 12 November, a group of radio astronomers led by Donald Backer (Berkeley) announced by International Astronomical Union telegram that they had found a pulsar in the constellation Vulpecula with a period of 1.558 milliseconds—twenty times shorter than that of the Crab pulsar, the fastest pulsar previously seen. The period of the first recorded pulsar, 1.337 seconds, discovered in 1967 by Jocelyn Bell and her colleagues at Cambridge, is much more typical.
Arms-limitation strategies
Authors: York Herbert F.
Published: August 2008

In 1934, when the Nazi terror was just beginning, and artificial radioactivity and the neutron had just been discovered, Leo Szilard invented the idea of a neutron chain reaction He believed there must be some atomic nucleus that would, upon absorbing one neutron, emit two neutrons and energy, and that these two neutrons would lead to four, and so on He did not know what nuclear process would be involved or what element would support that process. Nevertheless, he quickly went on to sketch two distinct devices based on such a neutron chain reaction.