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The article reports that Lawrence Berkeley National Laboratory (LBNL) has detected atoms of element 116, indicating progress in the quest to create element 120, the heaviest known element. Topics discussed include the methods used for synthesizing superheavy elements, the competitive landscape among international research facilities, and the challenges faced in achieving these scientific milestones.

The article focuses on the culture and convictions of researchers at U.S. national labs involved in nuclear research, exploring their perspectives on nuclear weapons and the moral challenges they face. Topics include the dual-use nature of nuclear science, the role of national labs in maintaining the nuclear arsenal, and the challenges posed by the resumption of large-scale plutonium pit production.

The atomic nucleus is composed of two different kinds of fermions: protons and neutrons. If the protons and neutrons did not interact, the Pauli exclusion principle would force the majority of fermions (usually neutrons) to have a higher average momentum. Our high-energy electron-scattering measurements using 12C, 27Al, 56Fe, and 208Pb targets show that even in heavy, neutron-rich nuclei, short-range interactions between the fermions form correlated high-momentum neutron-proton pairs. Thus, in neutron-rich nuclei, protons have a greater probability than neutrons to have momentum greater than the Fermi momentum. This finding has implications ranging from nuclear few-body systems to neutron stars and may also be observable experimentally in two-spin-state, ultracold atomic gas systems. [ABSTRACT FROM AUTHOR]

The article discusses the creation of the subatomic particle the Higgs boson. The author examines the role of several theorists that claimed to have invented the Higgs boson, which includes Peter Higgs, Tom Kibble, Gerald Guralnik, Carl Hagen, Francois Englert, and deceased theorist Robert Brout. Topics discussed include how the invention of the Higgs boson changed the standard model of physics, which is a quantum field theory, the challenges of constructing a standard model, such as finding the a Lagrangian function with the right gauge symmetries to explain the model's observed forces, and how the hypothetical boson particle came to be known as the Higgs boson.

The article discusses the teams of physicists at A Toroidal LHC Apparatus (ATLAS) and the Compact Muon Solenoid (CMS), two detectors at the Large Hadron Collider (LHC) of the European Organization for Nuclear Research (CERN) which are being used to search for the Higgs boson and study supersymmetry (SUSY). The ATLAS and CMS collaborations both involve thousands of scientists who compete with each other to make discoveries. Physicists including Martijn Mulders, Sara Strandberg, and Maria Spiropulu discuss competition between groups, concerns about unethical behavior, and the culture of CMS and ATLAS. INSET: U. S. Physicists, a Long Way From Home.

Quantum mechanically indistinguishable particles such as photons may show collective behavior. Therefore, an appropriate description of a light field must consider the properties of an assembly of photons instead of independent particles. We have studied multiphoton correlations up to fourth order in the single-mode emission of a semiconductor microcavity in the weak and strong coupling regimes. The counting statistics of single photons were recorded with picosecond time resolution, allowing quantitative measurement of the few-photon hunching inside light pulses. Our results show bunching behavior in the strong coupling case, which vanishes in the weak coupling regime as the cavity starts Casing. In particular, we verify the n factorial prediction for the zero-delay correlation function of n thermal light photons. [ABSTRACT FROM AUTHOR]

Chemical bonding dynamics are fundamental to the understanding of properties and behavior of materials and molecules. Here, we demonstrate the potential of time-resolved, femtosecond electron energy loss spectroscopy (EELS) for mapping electronic structural changes in the course of nuclear motions. For graphite, it is round that changes of milli--electron volts in the energy range of up to 50 electron volts reveal the compression and expansion of layers on the subpicometer scale (for surface and bulk atoms). These nonequilibrium structural features are correlated with the direction of change from sp² [two-dimensional (2D) graphene] to sp³ (3D-diamond) electronic hybridization, and the results are compared with theoretical charge-density calculations. The reported femtosecond time resolution of four-dimensional (4D) electron microscopy represents an advance of 10 orders of magnitude over that of conventional EELS methods. [ABSTRACT FROM AUTHOR]

The estimation of the entanglement of multipartite systems undergoing decoherence is important for assessing the robustness of quantum information processes. It usually requires access to the final state and its full reconstruction through quantum tomography. General dynamical laws may simplify this task. We found that when one of the parties of an initially entangled two-qubit system is subject to a noisy channel, a single universal curve describes the dynamics of entanglement for both pure and mixed states, including those for which entanglement suddenly disappears. Our result, which is experimentally demonstrated using a linear Optics setup, leads to a direct and efficient determination of entanglement through the knowledge of the initial state and single-party process tomography alone, foregoing the need to reconstruct the final state. [ABSTRACT FROM AUTHOR]

More than 99% of the mass of the visible universe is made up of protons and neutrons. Both particles are much heavier than their quark and gluon constituents, and the Standard Model of particle physics should explain this difference. We present a full ab initio calculation of the masses of protons, neutrons, and other tight hadrons, using lattice quantum chromodynamics. Pion masses down to 190 mega-etectron volts are used to extrapolate to the physical point, with lattice sizes of approximately four times the inverse pion mass. Three lattice spacings are used for a continuum extrapolation. Our results completely agree with experimental observations and represent a quantitative confirmation of this aspect of the Standard Model with fully controlled uncertainties. [ABSTRACT FROM AUTHOR]

The research potential is undisputed, but the price tag is $4 billion. The Super Collider, a 20-trillion electron volt colliding beam accelerator, is the focus of dispute between `big' and `little' science. INSET: Why go to 20 TeV?.

The article discusses an experiment investigating the existence of hypothetical dark matter particles, called weakly interacting massive particles (WIMPs), using the Coherent Germanium Neutrino Technology (CoGeNT) detector by scientists at an underground observatory in Soudan, Minnesota. Topics include experimental results that suggest researcher Juan Collar and colleagues of the University of Chicago, may have spotted a signal from dark matter in CoGeNT, the controversy surrounding Collar's remarks regarding a rival experiment, called XENON, by Columbia University, and a dispute among researchers regarding a claim by Italian researchers of the DAMA project that they had detected WIMPs.

Toroidal multipoles are fundamental electromagnetic excitations different from those associated with the familiar charge and magnetic multipoles. They have been held responsible for parity violation in nuclear and particle physics, but direct evidence of their existence in classical electrodynamics has remained elusive. We report on the observation of a resonant electromagnetic response in an artificially engineered medium, or metamaterial, that cannot be attributed to magnetic or charge multipoles and can only be explained by the existence of a toroidal dipole. Our direct experimental evidence of the toroidal response brings attention to the often ignored electromagnetic interactions involving toroidal multipoles, which could be present in naturally occurring systems, especially at the macromolecule level, where toroidal symmetry is ubiquitous. [ABSTRACT FROM AUTHOR]

Single spins in solid-state systems are often considered prime candidates for the storage of quantum information, and their interaction with the environment the main limiting factor for the realization of such schemes. The lifetime of an excited spin state is a sensitive measure of this interaction, but extending the spatial resolution of spin relaxation measurements to the atomic scale has been a challenge. We show how a scanning tunneling microscope can measure electron spin relaxation times of individual atoms adsorbed on a surface using an all-electronic pump-probe measurement scheme. The spin relaxation times of individual Fe-Cu dimers were found to vary between 50 and 250 nanoseconds. Our method can in principle be generalized to monitor the temporal evolution of other dynamical systems. [ABSTRACT FROM AUTHOR]

Projective measurement of single electron and nuclear spins has evolved from a gedanken experiment to a problem relevant for applications in atomic-scale technologies like quantum computing. Although several approaches allow for detection of a spin of single atoms and molecules, multiple repetitions of the experiment that are usually required for achieving a detectable signal obscure the intrinsic quantum nature of the spin's behavior. We demonstrated single-shot, projective measurement of a single nuclear spin in diamond using a quantum nondemolition measurement scheme, which allows real-time observation of an individual nuclear spin's state in a room-temperature solid. Such an ideal measurement is crucial for realization of, for example, quantum error correction protocols in a quantum register. [ABSTRACT FROM AUTHOR]

The article discusses an experiment that manipulated the transition of electromagnetic positive and negative frequencies in pulsating dielectric sheets, which creates a negative refracting lens similar to the Veselago lens. It examines the symmetric processes between time reversal and negative refraction along with previous studies on boundary conditions and refracting interface. It also proposes a scheme to exhibit subwavelength resolution and suggests four-wave mixing as an ideal system for optical frequencies' transition, in which it creates a hologram.

The article focuses on the new networking tools developed by the researchers for the storage of the instrument readings of Large Hadron Collider (LCH) powers in Switzerland. They are making floods of data for the production and processing of LCH, as well as for making it available for the study of the physicist worldwide. According to researchers Ian Foster and Steven Tuecke, they created an electricity grid in a deliberated analogy for the processing power, scientific instruments, and storage of the LCH devices.

The article focuses on the launching of the Large Hadron Collider (LCH) by European Organization for Nuclear Research (CERN) in Geneva, Switzerland. LCH, considered as the biggest atom smasher in the world, is now stretching through a 27-kilometer tunnel ring, aiming to produce fleeting bits of matter. According to CERN experimenter Maria Spiropulu, the first collision of the LCH will signify a real fun for them as they undergo several analyses to understand it. They will also use a smidgen data to rediscover standard models.

The article focuses on electron pairing theories in cuprate superconductors. In the mid-1980's, physicists do agree that electron pairs are significant because they can form a condensate that flows without resistance, but the interaction that causes the pairs to form are disputed. Many alternatives have been proposed for bosonic glue that hold the electron pairs together. However, the author argues that the need for bosonic glue is folklore rather than the result of scientific logic. He believes that it is a from the inappropriate assumption that superconductivity in these materials is described by a mathematical framework called the Eliasberg formalism. Moreover, it is said that electrons only interact, to a very good approximation through the Coulomb interaction.

The article reports on the claim by the Russian government on December 5, 2019 that it has suspended construction to convert a military site in Iran into a civilian nuclear research center.

Report on the discovery of the production of a Z particle at the Stanford Linear Accelerator Center (SLAC), five years into the project. The SLAC had been under pressure to produce a Z particle for funding reasons, and because European scientists are catching up to the US in this area. The collider itself and the two groups of scientists working on the project are adding to the pressure.

The article discusses the U.S. Department of Energy's (DOE's) role in researching neutrinos, antiparticles and nuclear decay. An overview of the DOE's nuclear physics budget, including its forecast to increase above the rate of inflation, is provided.

The article looks at the Large Hadron Collider (LHC) particle accelerator operated by the European Organization for Nuclear Research (CERN) near Geneva, Switzerland. It reports the LHC is going to be restarted in March 2015 after being out of service for two years for repairs, cites its role in the discovery of the Higgs boson subatomic particle, and discusses the prospects of other significant discoveries with the LHC related to the standard model of nuclear physics in the future.

The authors discuss the inauguration of the Synchrotron-light for Experimental Science and Applications in the Middle East (SESAME) project by several countries and organizations including Cyprus, Iran, and Iran in Jordan. Authors mention the history of the project which began in 1997 under the United Nations Educational, Scientific and Cultural Organization (UNESCO) and the European Organization for Nuclear Research (CERN).

The article reports on the suspension of an agreement on nuclear research and development (R&D) cooperation between Russia and the U.S.

The article discusses the future of particle physics research in the U.S. in the aftermath of the shutdown of the Tevatron particle collider located at the Fermi National Accelerator Laboratory (Fermilab). The recent history of the planning and budgeting of U.S. particle physics research by the U.S. Department of Energy is discussed, including delays and expenses that hinder implementation. A chart is presented on categories of future physics research and their leadership by researchers at the Large Hadron Collider, Fermilab, and within the U.S. physics community.

The article discusses research on imaging using scanning tunneling microscopy (STM) reported elsewhere in the issue by S. Loth et al. The researchers reportedly used atomic-resolution STM to observe the dynamics of electron spin relaxation after using STM-generated tunneling electrons to pump electron-spin excitations. An illustration of the experimentation is included. The experimental results are said to present a pathway for surface science studies of individual nanostructures in the nanosecond time realm.

The article discusses nuclear physics research using the Tevatron collider at the Fermi National Accelerator Laboratory, or Fermilab. As researchers there have not detected a nuclear particle called the Higgs boson, they want to operate the Tevatron for 3 additional years to allow them to do so. Fermilab co-spokesperson Dmitri Denisov is cited regarding plans to look for Higgs bosons in the range of 114 to 185 giga-electron volts.

The article discusses the discovery of element 117 by physicists at Russia's Joint Institute for Nuclear Research (JINR), noting their success in previous discoveries of elements 113 through 116 and 118. International competition among physics laboratories in finding new elements is noted. JNIR scientists are said to have uninterrupted access to a cyclotron devoted to element discovery. Other competing research facilities are said to include the U.S. Lawrence Berkeley National Laboratory and Germany's GSI Helmholtz Centre for Heavy Ion Research. Element 117 cannot be named until it is found in confirmatory research by a second laboratory.

The article focuses on the search for a weakly interacting massive particle (WIMP) that could be the source of what astrophysicists call dark matter in the Milky Way. The Cryogenic Dark Matter Search (CDMS) experiment that is being conducted at the Soudan Underground Laboratory in Minnesota is discussed. Topics include a sensor that can detect a dark matter annihilation signal during a CDMS experiment, the CDMS II Collaboration, the interaction of nucleon and WIMP, and target materials such as liquid noble gases.

The article discusses how changes in research funding, administrative changes, and Great Britain's economic problems that have left the British Science and Technology Facilities Council (STFC), in financial turmoil. Topics include an overview of how the STFC has tried to cope with budget cuts, such as paring down nuclear physics and astronomy research programs, and when STFC's financial troubles began.

The article discusses superradiance, a concept attributed to scientist Robert Dicke regarding cooperative, spontaneous photon emissions. It explains that superradiance depends on the number of atoms that are emitting photons. Single-photon superradiance is said to hold promise regarding ways to store quantum information and in understanding virtual processes. The article notes atom clouds, cavity quantum electrodynamics (QED), and quantum field theory. A detailed diagram is included to complement the discussion of photon emission concepts.

The article focuses on an experiment conducted by a team of physicists at the Fermi National Accelerator Laboratory (Fermilab) that aims to confirm the existence of a new particle in Switzerland. The positive results of the experiment are considered to be revolutionary, thus scientists are aiming to prove first the supposed Polarizzazione del Vuoto con LASer particle. Fermilab researchers performed the experiment by shining a laser through a high technology mirror. An extra superconducting magnet from Fermilab's Tevatron collider is likewise used to supply the testing field. Giovanni Cantatore, physicist at the University of Trieste in Italy, admits the less chances of their economical experiment, but expresses excitement over its possible outcome.

The article focuses on the move of the particle physicists in Europe, drawing up a road map for the future of particle physics. The physicists gives top billing to the nearly completed Large Hadron Collider at the European Organization for Nuclear Research commonly known as CERN situated just west of Geneva on the border between France and Switzerland. According to the author, the adopted road map runs parallel to the recently U.S. strategy but differs slightly about future machines. Other significant information relative to the matter are presented.

Focuses on the establishment of nuclear research reactors for nuclear engineering and science students in the U.S. Decline of the University research reactors on research activities; Percentage rate of increase of the doctor of philosophy degree; Improvement of instrumentation and facilities.

Describes the work in particle physics being done at CERN, the European Laboratory for Particle Physics. History of particle physics in Europe; Collaborative initiatives in Europe during the 1950s; CERN's role as scientific prototype; Reasons for coexistence between European facilities and national research institutes; Work on the Large Electron-Positron (LEP) storage ring and the Large Hadron Collider (LHC); Work at other European physics labs.

Report on operating problems with the experimental Stanford Linear Collider (electron-positron collider). Delays exploring the physics of the z particle.

While funding is not yet assured for all the third- generation synchrotron sources, accelerator scientists are struggling to design a machine that can provide ultrahigh- brightness light. The `1-to-2-GeV Synchrotron Radiation Source' at Lawrence Berkeley Laboratory could cost $98.7 million before its completion in five years.

Questions from the Senate have stalled the construction of a $225-million machine and prompted a second review of its scientific merits. Virginia's John Warner (R) told the appropriations subcommittee that his state should house the new accelerator, while Louisiana's Bennett Johnston (D) spoke about atomic structure and questioned the project's value for physics research.

France & Germany have reached an agreement; funding and location remain to be settled, but construction could begin next year. It is a French/German collaboration in building a 5- billion-electron-volt (GeV) synchrotron radiation facility, which used intense beams of x-rays to explore the structure of both organic and inorganic matter.

Four Groups Build More Efficient Atom Traps ULTRAHICH-resolution spectroscopy,atomic clocks of unprecedented accuracy, detailed studies of the kinetics of atomic collisions, and observation of unusual quantum phenomena are some of [...]

The article presents corrections for the articles "Iceberg alert for NIH," by H. R. Bourne and M. O. Lively from the July 27, 2012 issue, which discusses the U.S. National Institutes of Health, and "Stability at last for Australian Synchrotron?" by E. Finkel in the July 20, 2012 issue.