August 1, 2019 (updated August 1, 2019)
Published by Kalpit Veerwal
The stars in our universe have a magnetic field that interacts with the winds which they produce including our sun. As a result of the collaboration between the Sun’s magnetic field and the solar wind leads to the formation of a heliospheric magnetic field like a spiralling structure known as the Parker spiral. This spiral is important for administering the plasma processes that source the solar wind.
According to a new study at the University of Wisconsin-Madison, the physicists have reported the creation of a mini sun like a laboratory model of the Parker spiral system based on the idea of rotating plasma magnetosphere and measurement of the global structure and dynamic behaviour. The study has been published in Nature Physics.
Physicists have access to this Big Red Ball, which is a three-meter wide hollow sphere which contains different probes and a strong magnet at the centre. The helium gas is siphoned and ionized to create plasma and then an applied electric field alongside the magnetic field which copies the ideal case of spinning plasma and the electromagnetic fields of the sun. Estimations can be taken at numerous points inside the bass which enables physicists to study the solar phenomena in three dimensions.
They have an option to replicate the Parker Spiral, a magnetic field which covers the entire solar system, the magnetic field transmits straight out of the sun. From there onwards, the solar wind dynamics take over and haul the magnetic field into a spiral.
A graduate student in the Physics department at UW-Madison, Ethan Peterson said that the satellite measurements are pretty consistent with the Parker Spiral model, only at one point at a time and so can never make simultaneous and map it on a large scale map. The plasma from the sun’s plasma burps fuel up the slow solar winds.
The speed of light and magnetic field are probed and the data has mapped a region where plasma is moving fast enough and where the plasma could break off and eject radially. The ejections have been spotted by satellites and no one knows the reason as to what drives them. They found similar burps in the experiment and found out how they developed.
The work has shown that understanding fundamental physics of these processes is possible through laboratory experiments and the Big Red Ball being funded as a National User Facility allows scientists to study the physics of solar winds. The Earthbound experiments can not replace satellite missions like the Parker Solar Probe which was launched in August 2018 can reach the Alfven surface and can even dip below it. It is expected to provide direct measurements of the solar wind.
Journal Reference: Nature Physics
April 26, 2019
Published by Kalpit Veerwal
Francesca Ferlaino and other researchers from Austrian Academy of Sciences and the University of Innsbruck created a report on Physical Review X on what they observed of the behavior of a supersolid in dipolar quantum gases made of dysprosium and erbium. Atoms are arranged in a crystalline pattern as well as they behave like a superfluid in a supersolid where particles can move even when there is no friction.
Dr. Lauriane Chomaz from the Institute for Experimental Physics at the University of Innsbruck and colleagues said that their work was mainly focused on attaining the supersolidity in helium but now the researchers are emphasizing more on atomic gases with strong dipolar interactions. Many experiments have been conducted and it has been observed and disclosed in one of the recent experiments that atomic gases have some common properties of that of superfluid helium and these features are the basic features required for achieving a basic condition with both spontaneous density modulation and global phase coherence.
Density modulation and global phase coherence are the indicators of supersolidity. The team created the two supersolids with the help of erbium and dysprosium quantum gases. The scientists said that they created different states by performing different experiments which will show the features of supersolidity by adjusting the relational strength among the particles in erbium quantum gases as well as the erbium quantum gases.
Dr. Francesca Ferlaino who is the senior author from the University of Innsbruck and the Institute for Quantum Optics and Quantum Information of the Austrian Academy of Sciences said that the way the erbium works is only for the short period of time and he also adds that their dysprosium realization shows an unmatched balance.
In this experiment, the state of supersolidity can not only live longer but the state of supersolidity can be straightforwardly attained through the process of evaporative cooling which can be started from a thermal sample. The simple principle here is like getting energized over a cup of tea. The principle here is removing the particles which are carrying most of the energies so that the gas slowly cools down and down and slowly achieves the quantum-degenerate stationary state along with the help of the characteristics of the supersolid at the thermal equilibrium.
Thus we can conclude here that the experiment offers a very thrilling hope for more experiments in the future and the theories as well since the state of the supersolid is a bit affected by dissipative dynamics or excitations which leads to the pavement so that it can probe its excitation spectrum and its superfluid behavior.