EPJ Plus Highlight - Proving Einstein right using the most sensitive Earth rotation sensors ever made

Physicists have now found a way to measure Earth's rotation in an extremely accurate way. https://stock.adobe.com/ie/stock-photo/planet-earth-in-space/60274978

A new study use the most precise inertial sensor available to date to measure whether Earth partially drags inertial frames along with its rotation

Einstein’s theory of gravity, also referred to as General Relativity, predicts that a rotating body such as the Earth partially drags inertial frames along with its rotation. In a study recently published in EPJ Plus, a group of scientists based in Italy suggests a novel approach to measuring what is referred to as frame dragging. Angela Di Virgilio of the National Institute of Nuclear Physics, INFN, in Pisa, Italy, and her colleagues propose using the most sensitive type of inertial sensors, which incorporate ring lasers as gyroscopes, to measure the absolute rotation rate of the Earth.

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EPJ Plus Highlight - Does the universe have a rest frame?

A simplified diagram showing the basic idea of the experimental design.

Experiment aims at resolving divergence between special relativity and standard model of cosmology

Physics is sometimes closer to philosophy when it comes to understanding the universe. Donald Chang from Hong Kong University of Science and Technology, China, attempts to elucidate whether the universe has a resting frame. The results have recently been published in EPJ Plus.

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EPJ Plus Focus Point - Plants for food, energy and sustainability

Guest Editors: G. Alimonti, S. Johansson and L. Mariani

After a very long hunting-gathering period, the first agricultural civilizations were born at the end of the last ice age. Agricultural practices generated a surplus of food, which was a prerequisite for the birth of modern societies. During the twentieth century, the modern agriculture was developed and now yields more food than ever before: less than 20% of our global population works to provide the whole mankind with food.

As environmental problems and resource constraints are arising, we now turn to agriculture in the hope for solutions regarding future sustainability. Could agriculture provide us with both food and fuel? Could we contribute to climate change mitigation by letting plants exploit the carbon dioxide that has been accumulated in the atmosphere? There are many promises, and we know that plants are our ultimate companions in life. However, more systemic methods are required to cope with multi-functionality and living systems so that we do not end up causing new problems as we try to cope with those already there.

This EPJ Plus Focus Point addresses the present and historical development of agriculture, perspectives of plant exploitation for food and energy production in a logic of social, economic and environmental sustainability. The articles are freely accessible until 20 April. For further information read the Editorial

EPJ Plus Focus Point - Rewriting Nuclear Physics textbooks: 30 years with radioactive ion beam physics

Guest editors: N. Alamanos, C. Bertulani, A. Bracco,
A. Bonaccorso, D. Brink and G. Casini

This collection of articles contains the lectures given at the Summer School "Re-writing Nuclear Physics textbooks: 30 years of radioactive ion beam physics`` which was held at the INFN Sezione di Pisa and Department of Physics of the University of Pisa during the week 20-24 July 2015.

The school celebrated thirty years since the publication of the first papers (I. Tanihata et al., Phys. Rev. Lett. 55, (1985) 2676 and P.G. Hansen, B. Jonson, Europhys. Lett. 4, (1987) 409) in which radioactive ion beams (RIBs) were used to study properties of atomic nuclei. The school consisted of twelve lectures published here and freely accessible until 24 April 2017. Each lecture covers a topic contained in a standard Nuclear Physics textbook extended to show how our understanding has deeply changed due to the experience accumulated with RIB physic. The collection is directed mainly to third and fourth year undergraduate students but it could be seen also as an update for teachers of basic Nuclear Physics courses.

For further information read the Editorial here.

EPJ Plus Highlight - Smart multi-layered magnetic material acts as an electric switch

The structure of ultrathin films of a cobalt nickel alloy.

New study reveals characteristic of islands of magnetic metals between vacuum gaps, displaying tunnelling electric current

The nanometric-size islands of magnetic metal sporadically spread between vacuum gaps display unique conductive properties under a magnetic field. In a recent study published in EPJ Plus, Anatoliy Chornous from Sumy State University in Ukraine and colleagues found that the vacuum gaps impede the direct magnetic alignment between the adjacent islands - which depends on the external magnetic field - while allowing electron tunneling between them. Such externally controlled conducting behaviour opens the door for applications in electronics with magnetic field sensors - which are used to read data on hard disk drives - biosensors and microelectromechanical systems (MEMS), as well as in spintronics with magnetic devices used to increase memory density.

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EPJ Plus Highlight - 100% renewable energy sources require overcapacity

Germany's greenhouse gas (GHG) emissions from 2002 to 2015 and the political target for 2020 (bars).

To switch electricity supply from nuclear to wind and solar power is not so simple

Germany decided to go nuclear-free by 2022. A CO2-emission-free electricity supply system based on intermittent sources, such as wind and solar - or photovoltaic (PV) - power could replace nuclear power. However, these sources depend on the weather conditions. In a new study published in EPJ Plus, Fritz Wagner from the Max Planck Institute for Plasma Physics in Germany analysed weather conditions using 2010, 2012, 2013 and 2015 data derived from the electricity supply system itself, instead of relying on meteorological data. By scaling existing data up to a 100% supply from intermittent renewable energy sources, the author demonstrates that an average 325 GW wind and PV power are required to meet the 100% renewable energy target. This study shows the complexity of replacing the present primary energy supply with electricity from intermittent renewable sources, which would inevitably need to be supplemented by other forms of CO2-free energy production.

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EPJ Plus Highlight - New neuron dynamics model better fitted to the biological reality

The phase trajectories of the solutions for the simplified biologically relevant HH model and the scaled theoretical FHN model for neuron dynamics (black curve).

Scientists have now adopted a qualitative theoretical neuroscience model commensurate with actual measurements of neurons' dynamics

Neuroscientists are currently working diligently to understand the dynamics of thousands of coupled neurons. Understanding how they operate requires accurate models. The trouble is that each of the existing neuroscience models has its own shortcomings. Russian physicists have, for the first time, developed an effective method for solving the equations of a well-known theoretical neuroscience dynamic model and make it more biologically relevant. These findings have just been published in EPJ Plus by Eugene Postnikov and Olga Titkova from Kursk State University, Russia. They could not only help resolve problems in the neurosciences, but could also provide a deeper understanding of neuronal activity in the emerging sector of neurovascular dynamics, which describes the interplay between the brain's neurons and the blood flow.

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EPJ Plus Highlight - Pushing the boundaries of magnet design

Representation of the magnetic anisotropy of single ions contained in the rare-earth components of the magnets in the study.

New method to make permanent magnets more stable over time

For physicists, loss of magnetisation in permanent magnets can be a real concern. In response, the Japanese company Sumitomo created the strongest available magnet—one offering ten times more magnetic energy than previous versions—in 1983. These magnets are a combination of materials including rare-earth metal and so-called transition metals, and are accordingly referred to as RE-TM-B magnets. A Russian team has now been pushing the boundaries of magnet design, as published in a recent study in EPJ Plus. They have developed methods to counter the spontaneous loss of magnetisation, based on their understanding of the underlying physical phenomenon. Roman Morgunov from the Institute of Problems of Chemical Physics at the Russian Academy of Sciences and colleagues have now developed a simple additive-based method for ensuring the stability of permanent magnets over time, with no loss to their main magnetic characteristics.

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EPJ Plus Highlight - Improving safety of neutron sources

Sampling of Lead-Bismuth-eutectic material/cover gas-interface sample consisting of solid material forming a powdery crust onto the steel wall.

Testing liquid metals as target material bombarded by high-energy particles

There is a growing interest in the scientific community in a type of high-power neutron source that is created via a process referred to as spallation. This process involves accelerating high-energy protons towards a liquid metal target made of material with a heavy nucleus. The issue here is that scientists do not always understand the mechanism of residue nuclei production, which can only be identified using spectrometry methods to detect their radioactive emissions. In a new study examining the radionuclide content of Lead-Bismuth-eutectic (LBE) targets, scientists at the Paul Scherrer Institute Villigen (PSI) found that some of the radionuclides do not necessarily remain dissolved in the irradiated targets. Instead, they can be depleted in the bulk LBE material and accumulate on the target's internal surfaces. These findings have recently been published in EPJ Plus by Bernadette Hammer-Rotzler affiliated with the PSI and the University of Bern, Switzerland, and colleagues from Switzerland, France and Sweden. The results improve our understanding of nuclear data related to the radionuclides stemming from high-power targets in spallation neutron sources. They contribute to improving the risk assessment of future high-power spallation neutron beam facilities --including, among others, the risk of erroneous evaluation of radiation dose rates.

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EPJ Plus Highlight - Sweden’s 100% carbon-free emissions challenge

The figure shows the reduced load along with the original nuclear power, the contribution of which is halved. It also shows the increased contribution from wind necessary and that from a backup system.

Replacing nuclear power with wind power doesn't make sense in Sweden, study shows

The Swedish power supply is largely free of carbon emissions. Indeed, it is mainly based on a combination of hydroelectric and nuclear power combined with power exchange with neighbouring Scandinavian countries. A study published in EPJ Plus investigates the possibility of replacing nuclear power with wind power, which is by nature intermittent. According to the study, this, in turn, would finally lead to a reduction in the use of hydroelectricity if the annual consumption remained constant. The authors of the study conclude that a backup system, based on fossil fuel, namely gas, would be required in combination with wind power. In such a scenario, the CO2 emissions would double. Fritz Wagner from the Max Planck Institute for Plasmaphysics, Greifswald, Germany, and Elisabeth Rachlew from the Royal Institute of Technology, Stockholm, Sweden, therefore conclude that it would not be a viable option.

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